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1.
Swertia cordata (G. Don) C.B. Clarke is one of the potential medicinal plants extensively used in eastern traditional medicine such as Unani, Ayurveda, Siddha, and in traditional Tibetan and Chinese medicine. S. paniculata is the common adulterant of S. cordata at herbal shops and markets but S. paniculata is also used in number of herbal formulations. The present study was conducted to use microscopic, pharmacognostic, and phytochemical techniques as a tool for the authentication of herbal drug chiraita (S. cordata). In herbal markets, mixing, adulteration, and use of spurious materials as substitute have become a major concern for herbal practitioners, local user, and industry for reasons of safety and efficacy. Therefore, authentication of medicinal plants is of utmost importance at each level of drug research. In the present study, anatomical features of two species showed a great diversity, as irregular epidermal cells and nonglandular, unicellular trichomes were found in S. cordata while in S. paniculata epidermal cells were hexagonal in shape and trichomes were A‐shaped. Antioxidant activity of two species showed a great variation where IC50 value recorded for S. cordata was 208 μg/mL, while for S. paniculata IC50 was 624 μg/mL. The study can serve as an important source of information to achieve the authenticity and to evaluate the quality and purity of the plant material in accordance to WHO guidelines. As this species is greatly exploited, so conservation is highly recommended.  相似文献   

2.
Amphibian skin secretions contain a variety of bioactive compounds that are involved in diverse roles such as communication, homeostasis, defence against predators, pathogens, and so on. Especially, the caecilian amphibians possess numerous cutaneous glands that produce the secretory material, which facilitate survival in their harsh subterranean environment. Inspite of the fact that India has a fairly abundant distribution of caecilian amphibians, there has hardly been any study on their skin and its secretion. Herein, we describe, using light microscopy and electron microscopy, two types of dermal glands, mucous and granular, in Gegeneophis ramaswamii. The mucous glands are filled with mucous materials. The mucous‐producing cells are located near the periphery. The granular glands are surrounded by myoepithelial cells. A large number of granules of different sizes are present in the lumen of the granular gland. The granule‐producing cells are present near the myoepithelial lining of the gland. There are small flat disk‐like dermal scales in pockets in the transverse ridges of the posterior region of the body. Each pocket contains 1–4 scales of various sizes. Scanning electron microscopic (SEM) study of the skin surface showed numerous funnel‐shaped glandular openings. The antibacterial activity of the skin secretions was revealed in the test against Escherichia coli, Klebsiella pneumoniae, and Aeromonas hydrophila, all gram‐negative bacteria. SEM analyses confirm the membrane damage in bacterial cells on exposure to skin secretions of G. ramaswamii.  相似文献   

3.
细菌种类的快速识别在牙病防治中具有重要的应用价值。以牙周病原菌为研究对象,建立了DNA快速扩增的自然对流聚合酶链式反应(PCR)方法及毛细管电泳荧光光学检测系统。研究表明,当毛细管有效长度为8cm、电场强度为100V/cm时,50bp DNA ladder在筛分介质为0.5%HEC(羟乙基纤维素)(1 300K)中的分离效果最佳。毛细管电泳结果表明,采用自然对流法可以在25min内在圆柱腔体中实现牙周病原菌的快速PCR。  相似文献   

4.
时域式PCR生物芯片中温度动力学研究进展   总被引:2,自引:1,他引:2  
综述了国内外时域聚合酶链式反应生物芯片中温度动力学研究,包括TD-PCR反应系统加热/冷却速率、温度控制精度、温度均匀性以及热设计的理论模型等。  相似文献   

5.
传统PCR(polymerase chain reaction)仪对样品反应池壁温度进行接触式测量与温控,存在测量迟滞大、无法直接控制试剂温度的缺点。研制的电化学实时定量PCR温控系统采用红外温度传感器、热源温度传感器以及环境温度传感器分别测量试剂表面热辐射、热源与反应池壁温度与环境温度,并提出序贯双卡尔曼滤波估计算法对三点温度数据进行信息融合从而估计出试剂表面温度真实值。该算法中迭代卡尔曼滤波器(iterated extended Kalman filter,IEKF)与线性卡尔曼滤波器(Kalman filter,KF)顺序运行,结合了IEKF非线性估计收敛快与KF实时性高的优点,克服了红外测温噪声大,易受环境、被测物热辐射率等因素影响的缺点。试剂温度的估计值作为反馈输入到基于FPAA(field programmable analog array)的可动态配置PID控制器中构成闭环控制,同时微控制器根据不同温控阶段的控制要求对PID控制器进行配置,从而提高温控效率。实验表明,滤波估计后红外测温精度由2℃提高至0.3℃;试剂表面温度监控与可动态配置PID使得PCR温控更加准确高效;PCR产物测试结果优于市面上PCR仪、恒温时间设置更加合理。  相似文献   

6.
Rhus succedanea is generally traded, distributed, and sold in the markets in its crude and raw form. This may have been mixed with adulterants, mismanaged by malpractices, and substituted with other closely related drugs having different effect. This study is therefore carried out to authenticate the plant through pharmacognostic evaluations including morphological microscopic and physio‐chemical features. Morphologically, the Rhus is a perennial small sized deciduous tree, locally, called as Rakhkal in Pashto and Kakarsingi in Urdu. The organoleptic evaluation showed that leaf had pleasant, aromatic odor, and astringent taste. Anatomy of the midrib has shown a typical dicot histological differentiation. The leaf was hypostomatic showing anomocytic stomata with average stomatal number 27.1 ± 7.2 and stomatal index 14 ± 3.63. The average vein islet, vein termination, and palisade ratios were 13.6 ± 3.04, 10.21 ± 1.92, and 6 ± 2.01, respectively. Leaf powder showed the existence of various types of tissues. Fluorescence study and percentage extractive values were also carried out. The phytochemical screening showed the presence of carbohydrates, protein, alkaloids, phenols, flavonoids, terpenoids, and anthraquinones, whereas tannins and fixed oil was not detected. Quantitatively highest number of alkaloids 16% and flavonoids 19% in leaf was detected. The above parameters, being reported to the first time for, and are significant toward establishing the microscopic and pharmacognostic standards for future identification and authentication of genuine herbal drug.  相似文献   

7.
Fish erythrocytes are very sensitive to environmental pollution because they exhibit pathological alterations before appearance of other external symptoms, may be used as reliable toxicity bioindicators. Microscopic analysis can be a useful tool in early detection of alterations in erythrocyte morphology due to different environmental stressors, and in predicting organism's possible response ways. This study aims to evaluate the toxicity of a polluted freshwater lake on the erythrocytes of crucian carp fish, Carassius carassius, using digital light microscopy (DLM). Scanning DLM micrographs revealed the presence of nuclear and cytoplasmic abnormalities like micronucleus, nuclear buds, lobed nucleus, deformed nucleus, vacuolated cytoplasm, and echinocyte in the erythrocytes of crucian carp fish from a polluted lake. The obtained results substantiate that computation of erythrocyte morphological damages as biomarkers of exposure, through digital light microscopy software, can be effectively used as a toxicological tool.  相似文献   

8.
Molecular analyses such as fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) are demanded to improve diagnostic accuracy in addition to immunohistopathology of bone marrow (BM) trephine specimens. Conventional BM embedding method needs decalcification, and its procedure may impair tissue morphology and DNA quality. Here, we report an undecalcified method by which glycol methacrylate resin is polymerized at low temperature (4°C). Using this method, BM enzyme activity and antigenic determinants are well preserved, and moreover, DNA extracted from plastic embedding sections is suitable for PCR amplification and sequencing, FISH analysis can be well done because of the DNA integrity of BM sections. If working with BM trephine specimen, our protocol offers the possibility to combine superior morphology with modern molecular analysis. Microsc. Res. Tech. 73:1067–1071, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

9.
为了解决高通量数字聚合酶链式反应(dPCR)基因芯片荧光激发问题,设计了一套荧光激发测控系统。系统根据荧光染料的激发光谱特性,选择大功率窄带LED作为荧光激发光源,并通过STM32微处理器系统进行控制。该荧光激发系统有FAM、HEX和ROX三个荧光激发通道,各通道LED激发功率能够分别调节。系统最大输出电流为8 A,单通道最大输出功率为3 W,调节精确度1.0%,系统一次可完成dPCR基因芯片9 600个微液滴的荧光激发和采集。测试实验结果表明,系统达到了设计指标和应用需求。  相似文献   

10.
The General Conference of Weight and Measures (CGPM) with its Resolution 12 has officially prospected the adoption, possibly at the next General Conference of 2011, of new definitions for kilogram, ampere, kelvin and mole using fundamental constants as reference quantities. Thus, the outlines and features of the SI after that date are worthy to be considered and a general afterthought of the metrological activity in the new situation to be attempted.The future realisations of units will greatly benefit from the accelerated endeavour to determine the relevant fundamental constants with the minimum possible uncertainty before their values are fixed by definition. In fact, many of those experiments will become realisations of units when the new definitions are adopted.To define the units by reference to fundamental constants implies to abandon the identification of the unit with its primary standard, as in the old metrological tradition. To realise a unit will definitely consist in assigning a value to a primary standard, consistent with the fixed values of the reference constants, by means of an experimental procedure, independent of a specific definition, which could even not exist. The primary standard should be suitable to dissemination by direct comparison, thus essentially stable and accessible with the highest precision, while the role of the realisation experiment would be mainly related to indirect measurements, typical of scientific activity, which involves the coherence of the unit system. The two distinct roles, of unit realisation and primary standard, correspond to different uncertainty components, of which only one is implied in dissemination activity, just aiming at compatibility of measurements of a specific quantity. Each of the two uncertainty components has a different evolution from the time of the unit redefinition.These last considerations could validly contribute in critical issues, such as deciding whether the time for a unit redefinition has come or it should be preferable to wait for new and better experiments before fixing the value of a constant. This could be the case for the kilogram redefinition.  相似文献   

11.
针对现有的人工吊装送料方式吊装安全性差、效率低、可靠性不高[1],吊装过程中的工件晃动和放置时的冲击力大,易造成切割工件和工位的损坏问题,提出一种新型的待料装置以及与工件的接触面积小、不易与工件粘接、不易损坏和能有效支承切割的支承板,通过实物制造并投入使用可知,两者具有安全性好、可靠性高、生产效率高和节约成本等优点。  相似文献   

12.
The kinetics of molybdenum-sulphur compounds as anti-wear and extreme pressure additives are studied on a V-block-pin testing machine. The surface films of pins are analysed by Auger electron spectroscopy (AES). The apparent reaction order in the general kinetic equation can be determined from the experimental data. The results show that the composition of the surface film depends on the relative reaction rates of sulphidation and oxidation and can be found from the AES profile, where k is the reaction rate constant. The surface film of a mixture of iron oxide and sulphide possesses better anti-wear properties than the sulphide film alone.  相似文献   

13.
In all over the world, herbal drugs are usually adulterated with similar species or varieties due to incorrect identification. Most of herbal products devoid purity and quality, therefore an attempt was carried out to identify plant species and authenticate its herbal drug products from Mentha suaveolens. Microscopy tools provide an excellent platform to identify plants at species level. In this study, microscopic and pharmacokinetic parameters of M. suaveolens were observed. Plant species were collected from high diverse areas of Northern Pakistan. Macro and micro‐morphology including palynology and anatomical features were analyzed to study M. suaveolens. Species characteristics were studied, while implementing microscopic techniques for the delimitation and identification of the species. Traditionally Mentha species are used to cure several diseases that is, digestive disorders, respiratory disorders. Micromorphology (stem, leaves, flowers structure, length etc.), palynology (shape, size of pollen etc.), and anatomical characters (types of stomata, epidermal cell shape, and trichomes) were studied. Micromorphology and anatomical characters were of great interest and significance to discuss the taxonomy of the species. Taxonomic characters were studied to characterize and authenticate the species. The aim of the present study is to observe in detail the taxonomic identification of the species in term of morphology, palynology, and foliar epidermal anatomy for the correct identification along with their medicinal uses in the area.  相似文献   

14.
The practical difficulty of parenteral application of fish vaccines against devastating fish diseases diverted the interest toward oral vaccination. Search for effective methods to enhance the oral uptake of viral and bacterial vaccines is continuing. The current research focus on a new role of mucosal fish vaccine adjuvants inducing the antigen uptake by enhancing vascularity or increasing intestinal permeability. Some inflammatory substances cause reversible pathology to the intestinal epithelium, which could be employed for the transepithelial passage of vaccine particles. The natural inflammatory substances used were capsaicin, piperine, and okadaic acid as 1 mg, 2 mg, and 1 μg/fish, respectively. Two inactivated vaccines were used as antigens to test the effect of these inflammatory substances in two different fish hosts. Tested vaccines were inactivated redspotted grouper nervous necrosis virus vaccine in sevenband grouper (Epinephelus septemfasciatus) and inactivated Edwardsiella tarda vaccine in red sea bream (Pagrus major) fish models. The inflammatory substances and each vaccine were anally intubated to fish. Capsaicin proved to be effectively aiding the transepithelial passage of vaccine particles more than piperine, while okadaic acid had no detectable effect.  相似文献   

15.
The molecular basis of hearing is less well understood than many other senses. However, recent studies in Drosophila have provided some important steps towards a molecular understanding of hearing. In this report, we summarize these findings and their implications on the relationship between hearing and touch. In Drosophila, hearing is accomplished by Johnston's Organ, a chordotonal organ containing over 150 scolopidia within the second antennal segment. We will discuss anatomical features of the antenna and how they contribute to the function of this flagellar auditory receptor. The effects of several mutants, identified through mutagenesis screens or as homologues of vertebrate auditory genes, will be summarized. Based on evidence gathered from these studies, we propose a speculative model for how the chordotonal organ might function.  相似文献   

16.
推药机中的推药链采用的是一种刚性链条,刚性链条具有普通链条的柔性。目前刚性链条都是采用滚子链条和链轮,这种普通滚子链结构简单,容易设计及安装。但滚子链传动时啮合冲击较大,且会产生较大的多边效应,造成传动效率低,传动不稳定。齿形链是一种共轭啮合传动,在传动时啮合平稳,还可以减小多边效应。基于这个现状用仿真软件分析两种链条传动特点得出齿形链的传动优势。  相似文献   

17.
The present study focused to elucidate the promising role of probiotics in the fish culture, by employing microscopic and biochemical parameters to rationalize the possible outcomes. After preliminary feeding trial histopathological analysis revealed clear and visible changes in the intestinal and liver cells of CTRL (control group) compared to probiotics supplemented group, the bacterial inoculations resulted in shorten and swelled villi, while liver kupffer cells increased many folds in the CTRL. Moreover, there was clear hypertrophy and lamellar fusion in the gills tissues examined under microscope. Furthermore, intriguing results were obtained, such as a substantial increase in the weight gain, specific growth rate (%BW/day), FCE%, survival%, and improved secretions of amylase, cellulase, and protease activities. Likewise, high crude protein, fats content, while low moisture and total Ash was noticed in EXP I (Probiotics supplemented) compared to CTRL. The microscopic and biochemical analysis disclosed the positive role of probiotics on the fish health, thus we suggest its supplementations in the fish diet.  相似文献   

18.
We used scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to observe the oral organelle, cytopharynx, and subpellicular structure of a Dileptus sp. The main results were as follows: (a) the cytostome was located on the ventral surface of the base of the beak, surrounded by a periportal matrix that integrated 135 microtube bundles. When these microtube bundles contract, radially arranged into a disk, the cytostome was closed. When these microtube bundles were stretch, they fell into the cytostome and opens. The diameter of the cytostome was about 16 μm regardless of its closure or opening, indicating that the contraction or elongation of these microtube bundles did not change the size of the cytostome, which was only related to whether it blocked the cytostome, thus determining the opening and closing of the cytostome. There were many microtube bundles on two sides of the feeding trough, which could widen or narrow the feeding trough and facilitate beak feeding. (b) The cytopharynx was basket‐like without a bottom with a diameter of about 6 μm and was woven from two kind fibers about 0.08 and 0.19 μm. (c) There were two types of extrusomes under the pellicle. Using transmission electron microscopy,the Type I extrusomes showed narrow and long egg shape, its cross section was circular which is composed by various electronic density of concentric. Using the scanning electron microscope, they were two slightly thin clavate, the length was about 5 μm, the diameter of the middle section was about 0.75 μm, and the diameter of the two ends was about 0.32 μm, they were distributed abundantly between the microtubule fasciculi which were located on both sides of the gap on the feeding groove. Using transmission electron microscopy, the Type II extrusomes showed egg shape. Using the scanning electron microscopy, they were about 1.6 × 0.8 μm in size, they were distributed abundantly under the body pellicle while rarely the proboscis. In addition, many different of developmental stages two types of extrusomes could be also seen in the cytoplasm. (d) There were very well‐developed fibrous systems under the pellicle that were woven from fibers about 0.14 μm in diameter that attached to the pellicle and bound some organelles in the cytoplasm (e.g., mitochondria, extrusomes) and other structures to the cytoplasm and maintained cell morphology. The results of this study not only supplement and enrich the morphological contents of the Dileptus sp., but also provide the basis for the study of the taxonomy of the Dileptus sp. It also provides a new method for researchers to explore the morphology and structure of ciliate cells under the cortex by SEM.  相似文献   

19.
Although scanning electron microscopy (SEM) has been broadly used for the examination of fixed whole insects or their hard exoskeleton‐derived structures, including model organisms such as Drosophila, the routine use of SEM to evaluate vulnerable soft internal organs and tissues was often hampered by their fragile nature and frequent surface contamination. Here, we describe a simple four‐step protocol that allows for the reliable and reproducible preparation of the larval and prepupal salivary glands (SGs) of Drosophila for SEM devoid of any surface contamination. The steps are to: first, proteolytically digest the adhering fat body; second, use detergent washes to remove contaminating coarse tissue fragments, including sticky remnants of the fat body; third, use nonionic emulsifying polysorbate emulsifiers to remove fine contaminants from the SGs surface; and fourth, use aminopolycarboxylate‐based chelating agents to detach sessile hemocytes. Short but repeated rinses in 100 μL of a saline‐based buffer between steps ensure efficient removal of remnants removed by each treatment. After these steps, the SGs are fixed in glutaraldehyde, postfixed in osmium tetroxide, dehydrated, critically point‐dried, mounted on aluminum stubs, sputter coated with gold–palladium alloy and examined in the SEM.  相似文献   

20.
Bauhinia forficata is a medicinal plant that has flavonoid components with hypoglycemic, antioxidant, hepatoprotective, antibacterial, antiviral and anti‐inflammatory action. Aim of this study is to evaluate the action of B. forficata alcoholic extract in the male genital system of adult male Wistar rats. For that, 20 adult male Wistar rats were distributed into two experimental groups: the B. forficata group, receiving B. forficata alcoholic extract (0.1 ml/10 g body weight/day) on alternate days, and the control group, receiving just the vehicle for 30 days straight both via gavage. On the 31st day, the animals were euthanized, and the testis and epididymis were collected for histopathological, biochemical, morphometric, and sperm count analysis. Mass spectrometry identified new compounds in the extract: trans‐caffeic acid, liquiritigenin, gallocatechin, and 2,4,6‐trihydroxyphenanthren‐2‐glycoside. Biochemical analysis showed higher total cholesterol levels in the testis and lower malondialdehyde levels in the testis and epididymis, in the B. forficata group. The mast cell count showed a reduction in degranulated mast cells in the caput region of the epididymis, in the B. forficata group. The luminal compartment of the caput and the epithelial of the epididymis cauda were reduced, whereas the stromal region of the epididymis caput was increased in the B. forficata group, compared with the control group. The testicular tissue was less impaired, considering that all the histological analyses were similar to the control. We believe that B. forficata alcoholic extract in the male genital system showed antioxidant action, especially in the epididymal tissue.  相似文献   

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