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101.
目的 厘清由于分类系统和种分类等级的变化、种鉴定等原因引起的药材标准中法定药用植物基源混乱的情况。方法 查询我国国家和各省市自治区的相关药材标准及权威分类学著作,对植物基源存疑的种,从植物系统分类、分类群等级和种鉴定等各方面进行考证。结果 我国国家和地方标准收载的法定药用植物中,来源于恩格勒系统山龙眼科至蓼科的共有105种,其中基源鉴定清晰,分类无问题,中文名和拉丁学名无混淆的63种,基源存疑有5个科共42种,其中由于属名的异名充作正名而引起拉丁名混乱的1种,属分类系统变化而造成种混淆的5种,种等级分类群的鉴定、归并不同而造成混淆的11种,中文名混淆的25种,并对有混淆的种进行考订纠正。结论 檀香科、桑寄生科、马兜铃科、蛇菰科及蓼科法定药用植物基源有一定问题,经过研究考订,这些问题得以厘清解决。  相似文献   
102.
In this work we describe the analgesic, anti-inflammatory and toxic activities as well as the phytochemical profile of the ethanol extract from Tabernaemontana catharinensis A. DC. (Apocynaceae) stem bark. Analgesic evaluation was carried out against chemical and thermal stimuli. Anti-inflammatory activity was investigated on carrageenan-induced edema in rats and toxicological studies (LD50) were conducted in mice. Phytochemical analyses were performed by standardized methodology. In an analgesic assay, acetic acid-induced writhings were significantly inhibited by extract doses of 37.5?mg/kg (40.97%), 75?mg/kg (77.70%) and 150?mg/kg (88.98%). A central analgesia was also observed using T. catharinensis extract at all doses tested, particularly noticed at 60 and 90?min following administration. The extract significantly reduced edema development by 30.35% (37.5?mg/kg), 34.46% (75?mg/kg), and 56.42% (150?mg/kg) when assessed 180?min following carrageenan intraplantar injection, demonstrating an effective anti-inflammatory action. The LD50 value was 2200?mg/kg. Phytochemical analyses of ethanol extract from Tabernaemontana catharinensis stem bark showed the presence of alkaloids and terpenoids, which may be responsible for the observed pharmacological activities described in this work.  相似文献   
103.
104.
This study aimed to establish the effect of Sambucus ebulus L. (SE) ripe fruit infusion on body weight, blood pressure, glucose levels, lipid profile and antioxidant markers in healthy volunteers in respect of its possible protective activity against cardiovascular diseases and other oxidative stress-related diseases. The study involved 21 healthy volunteers, aged between 20 and 59, BMI 23.12?±?1.31, who consumed 200?ml SE infusion/day for a period of 30?d. Blood samples were collected before and at the end of the intervention. Significant decrease in triglycerides (14.92%), total cholesterol (15.04%) and LDL-C (24.67%) was established at the end of the study. In addition, HDL-C/LDL-C ratio increased by 42.77%. Improved serum antioxidant capacity and total thiol levels were also established. The results presented in this first human intervention study with SE fruit infusion indicate the potential of the plant to improve lipid profile and serum antioxidant capacity in humans.  相似文献   
105.
目的 考察在自然干燥、热风干燥、减压真空干燥方式下的黄芪药材经炮制成饮片后,药效成分的提取动力学。方法 以传统水煎煮法对黄芪饮片进行提取,建立提取动力学模型,比较黄芪药材经自然干燥、热风干燥、减压真空干燥3种初加工方式对饮片中4个评价指标(浸出物、黄芪多糖、毛蕊异黄酮葡萄糖苷、黄芪甲苷)提取效率差异。结果 3种干燥方式导致黄芪药材切面品相不一,提取动力学均与一级动力学模型拟合效果最佳,其中减压干燥动力学拟合方程斜率最大,提取效率最高。结论 减压干燥方式4个评价指标的药材-饮片转移率高,干燥、提取速率快,可作为传统干燥方式的替代干燥方式。不同干燥方式不仅对药材品相有影响,同时对药材制成饮片及后续饮片制成制剂过程中评价指标的提取效率也有影响,说明干燥等药材初加工是药材-饮片-制剂品质传递过程中的重要环节,应引起足够的关注。  相似文献   
106.
Cigarette smoking is an important risk factor for chronic obstructive pulmonary disease (COPD), yet its pathogenic mechanisms are not yet fully understood. Endothelial dysfunction is known to be involved in the pathogenesis of COPD. A detailed understanding of the mechanism involved in its progression would have a substantial impact on the optimization and development of treatment strategies. Here, we report that the expression of SIRT4, a mitochondrial sirtuin, is markedly down-regulated in cigarette smoke extract (CSE)-treated human pulmonary microvascular endothelial cells (HPMECs). Overexpression of SIRT4 significantly inhibits CSE-induced mononuclear cell adhesion to HPMECs. Consistently, we found that overexpression of SIRT4 attenuates the induction of vascular cell adhesion molecule 1 (VCAM-1) and E-selectin. Importantly, SIRT4 was found to negatively regulate CSE-induced NF-κB activation via inhibiting the degradation of IκBα. Moreover, we also found that proinflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, the downstream target genes of NF-κB, are also inhibited by overexpression of SIRT4. These results suggest that SIRT4 protects HPMECs exposed to CSE stress via a mechanism that may involve the NF-κB pathway. Strategies based on the enhancement of SIRT4 may prove to be beneficial in the treatment of cigarette smoking caused COPD.  相似文献   
107.
108.
In eukaryotes, secretory proteins traffic from the endoplasmic reticulum (ER) to the Golgi apparatus via coat protein complex II (COPII) vesicles. Intriguingly, during nutrient starvation, the COPII machinery acts constructively as a membrane source for autophagosomes during autophagy to maintain cellular homeostasis by recycling intermediate metabolites. In higher plants, essential roles of autophagy have been implicated in plant development and stress responses. Nonetheless, the membrane sources of autophagosomes, especially the participation of the COPII machinery in the autophagic pathway and autophagosome biogenesis, remains elusive in plants. Here, we provided evidence in support of a novel role of a specific Sar1 homolog AtSar1d in plant autophagy in concert with a unique Rab1/Ypt1 homolog AtRabD2a. First, proteomic analysis of the plant ATG (autophagy-related gene) interactome uncovered the mechanistic connections between ATG machinery and specific COPII components including AtSar1d and Sec23s, while a dominant negative mutant of AtSar1d exhibited distinct inhibition on YFP-ATG8 vacuolar degradation upon autophagic induction. Second, a transfer DNA insertion mutant of AtSar1d displayed starvation-related phenotypes. Third, AtSar1d regulated autophagosome progression through specific recognition of ATG8e by a noncanonical motif. Fourth, we demonstrated that a plant-unique Rab1/Ypt1 homolog AtRabD2a coordinates with AtSar1d to function as the molecular switch in mediating the COPII functions in the autophagy pathway. AtRabD2a appears to be essential for bridging the specific AtSar1d-positive COPII vesicles to the autophagy initiation complex and therefore contributes to autophagosome formation in plants. Taken together, we identified a plant-specific nexus of AtSar1d-AtRabD2a in regulating autophagosome biogenesis.

Autophagy is a conserved catabolic process characterized by the de novo generation of a double-membrane structure called an autophagosome with a fundamental function in the bulk turnover of cytoplasmic components, including proteins, RNAs, and organelles. Genetic studies in yeast have elucidated the molecular machinery of autophagy, whereby 42 autophagy-related (ATG) genes have been identified (13). These ATG genes are highly conserved among eukaryotes but often have multiple isoforms in other higher organisms, in particular in sessile plants. Albeit increasing understanding on the molecular function of Atg proteins in acting hierarchically on the phagophore assembly site (PAS) to produce autophagosomes, the origin of the autophagosomal membrane remains unclear in higher eukaryotes. Furthermore, the dedication of other membranes and machineries in the autophagy pathway remains under investigation.Plant autophagy is known to play important roles in the sessile lifestyle of plants, participating in seed germination, seedling establishment, plant development, hormone responses, lipid metabolism, and reproductive development (4). Plant autophagy research is advancing with findings not only on the counterparts of the yeast/mammalian Atg proteins but also dealing with some plant-unique factors functioning in different steps of autophagosome biogenesis, thereby uncovering novel mechanisms that might or might not be conserved in nonplant species (5). More interestingly, higher plants possess multiple protein isoforms of ATG machinery, whose functional heterogeneity in the autophagy pathway has only recently been unveiled (6).The coat protein complex II (COPII) machinery consists of five cytosolic components: the small GTPase Sar1, the inner coat protein dimer Sec23-Sec24, and the outer coat proteins Sec13-Sec31. These proteins are essential for COPII-coated vesicle formation, which buds from specialized regions of the ER, namely ER exit sites (ERESs) (7). Under nutrient-rich conditions, COPII vesicles mediate anterograde ER to Golgi transport. However, increasing evidence from yeast and mammals suggests that the COPII machinery or even COPII vesicles themselves may contribute to autophagosome formation when cells are starved for nutrients (816). Gene duplication events have occurred substantially in sessile plants during evolution, and the importance of distinct paralogs in environmental stress adaptation during plant development has been implied (17). Arabidopsis encodes multiple COPII paralogs in its genome, including five Sar1s, seven Sec23s, three Sec24s, two Sec13s, and two Sec31s (17). Increasing numbers of studies have pinpointed the functional diversity and importance of distinct COPII paralogs in ER protein export (1823). Nonetheless, the mechanism by which COPII vesicles are redirected to the autophagy pathway upon nutrient starvation, and their roles in autophagosome biogenesis, remains unclear. Furthermore, the participation of specific COPII paralogs in autophagy regulation remains unknown in plants.Here, we report on a role of a specific Sar1 homolog, AtSar1d, that modulates plant autophagosome biogenesis in concert with AtRabD2a. Large-scale proteomic analysis of the ATG interactome has revealed possible mechanistic connections between the ATG machinery and specific COPII components in plants. Cellular and biochemical analyses have shown that the dominant negative (DN) mutant of AtSar1d (AtSar1dDN) specifically perturbs YFP-ATG8 vacuolar degradation upon autophagic induction. Consistently, a transfer DNA (T-DNA) insertion mutant of AtSar1d exhibited starvation-related phenotypes. Notably, AtSar1d regulates autophagosome progression through specific recognition of ATG8e by a previously uncharacterized noncanonical motif. We further identify a plant-unique Rab1/Ypt1 homolog AtRabD2a that colocalizes with AtSar1d and ATG8 upon starvation by transient expression in Arabidopsis protoplasts. A DN mutant of AtRabD2a (AtRabD2aNI) perturbs autophagy flux, while AtRabD2a is indispensable for bridging the AtSar1d-positive COPII vesicles with the ATG1 complex, thus contributing to autophagosome biogenesis in plants. Our study therefore unequivocally demonstrates that the plant-specific COPII machinery regulates autophagosome biogenesis and sheds light on the evolutionary importance of gene duplication events in the plant autophagy pathway.  相似文献   
109.
The hydrogen isotope ratio of water cryogenically extracted from plant stem samples (δ2Hstem_CVD) is routinely used to aid isotope applications that span hydrological, ecological, and paleoclimatological research. However, an increasing number of studies have shown that a key assumption of these applications—that δ2Hstem_CVD is equal to the δ2H of plant source water (δ2Hsource)—is not necessarily met in plants from various habitats. To examine this assumption, we purposedly designed an experimental system to allow independent measurements of δ2Hstem_CVD, δ2Hsource, and δ2H of water transported in xylem conduits (δ2Hxylem) under controlled conditions. Our measurements performed on nine woody plant species from diverse habitats revealed a consistent and significant depletion in δ2Hstem_CVD compared with both δ2Hsource and δ2Hxylem. Meanwhile, no significant discrepancy was observed between δ2Hsource and δ2Hxylem in any of the plants investigated. These results cast significant doubt on the long-standing view that deuterium fractionation occurs during root water uptake and, alternatively, suggest that measurement bias inherent in the cryogenic extraction method is the root cause of δ2Hstem_CVD depletion. We used a rehydration experiment to show that the stem water cryogenic extraction error could originate from a dynamic exchange between organically bound deuterium and liquid water during water extraction. In light of our finding, we suggest caution when partitioning plant water sources and reconstructing past climates using hydrogen isotopes, and carefully propose that the paradigm-shifting phenomenon of ecohydrological separation (“two water worlds”) is underpinned by an extraction artifact.

The analysis of the stable isotope ratios of plant source water (δsource) is a powerful tool enabling the elucidation of a range of plant physiological, ecological, and hydrological processes from scales ranging from individual plants to the planet. δsource provides a foundation on which to form isotope signals of transpired water vapor and plant-derived biomarkers (i.e., cellulose and lipids) and thus is of high relevance to studies of terrestrial water fluxes (1, 2) and paleoclimate reconstructions (3, 4). δsource also contains information on the spatial and temporal origins of water used by plants and so is commonly used for investigating plant water uptake patterns under natural conditions (5, 6). Moreover, dual-isotope (δ2H and δ18O) analysis of δsource was critical in formulating the paradigm-shifting “two water worlds” (TWW) hypothesis, whereby ecohydrological separation exists between plant-accessible soil water pools and those recharging streams and groundwater (7, 8).Elucidation of the foregoing processes rest on the assumption that water extracted from plant stems is isotopically identical to water taken up by plant roots. Plant stem water is typically extracted with the cryogenic-vacuum distillation technique; δ generated with this method is hereinafter referred as δstem_CVD (9). For δstem_CVD to be an accurate indicator of δsource (i.e., δstem_CVD = δsource), two prerequisites must be met: 1) isotope change does not occur during root uptake and/or xylem transport of the source water (prerequisite I) and 2) stem water cryogenic extraction is a robust approach toward isotope recovery of xylem water (prerequisite II). The “δstem_CVD = δsource” assumption is generally valid for oxygen isotopes of water, but numerous studies have used hydrogen isotopes to assess source water, and here this assumption has faced scrutiny, as multiple studies have reported significant depletion in δ2Hstem_CVD compared with δ2Hsource in plants from various habitats (1018).A frequently invoked explanation for the observed δ2Hstem_CVD depletion is a violation of prerequisite I, as it is believed that symplastic uptake of source water into the root xylem can give rise to hydrogen isotope fractionation (10, 11, 13, 19). The available evidence (10, 11) in support of such an explanation is largely peripheral, because direct, unambiguous confirmation of water uptake/transport-related fractionation would require a comparison of deuterium in source water and water transported within xylem conduits (δ2Hxylem). However, this type of comparison is difficult owing to the technical challenges in obtaining targeted measurements of δ2Hxylem in most plants. Intriguingly, in a field-grown riparian tree species (Populus euphratica) in which δ2Hxylem measurement was made possible with the aid of a syringe-aided xylem sap bleeding technique, no significant difference was observed between δ2Hxylem and δ2Hsource (12). This led to the suggestion that, at least for the investigated species, δ2Hstem_CVD depletion arises not from a violation of prerequisite I, but rather from a violation of prerequisite II. The violation of prerequisite II has been deemed possible (12, 17) based on the argument that hydrogen isotope heterogeneity could be present within the bulk stem water (i.e., the outside xylem water may carry a metabolism-induced, more-depleted δ2H signature compared with the xylem water), potentially causing the stem water extraction technique to artifactually underestimate δ2Hxylem.Given the controvertible state of knowledge regarding the mechanism driving δ2Hstem_CVD depletion, it is imperative for us to build a better and more comprehensive understanding of the isotopic relationships among cryogenic extracted bulk stem water, source water, and xylem water in different plants, so as to put the application of the stem water cryogenic extraction technique in diverse fields on firmer ground. In this context, it should be pointed out that the xylem water direct sampling technique (12) is applicable only to a few riparian tree species. Recently, a new method relying on laser-enabled isotope measurement of water vapor in equilibrium with xylem water has demonstrated potential for in situ continuous monitoring of xylem isotope signatures in trees (20, 21); however, the method needs further development before it becomes broadly applicable to different plant types. Thus, a more generally applicable method is needed for determining xylem water signature across diverse plant types.Toward this goal, and capitalizing on the well-recognized mass balance-dictated principle that the isotopic composition of steady-state (SS) plant transpiration is identical to that of the xylem water supplying the plant canopy, we custom-designed a measurement system to enable independent quantification of xylem water isotope composition through isotope measurement of SS plant transpiration. This measurement system conferred the ability to compare values of δstem_CVD, δsource, and δxylem across a number of plant species of varying native habitats. The data allowed us to confirm the common presence of δ2Hstem_CVD depletion across all plant types measured, and also to demonstrate that this phenomenon is caused by cryogenic extraction-associated artifact and not by water uptake/transport-related fractionation. We also performed a rehydration experiment to illustrate that the extraction artifact is unrelated to within-stem isotope heterogeneity as has been recently suggested, but rather is more likely linked to a deuterium-exchange process that occurs dynamically during cryogenic extraction. Using the TWW hypothesis as an example, we further discuss the ramifications for ecological/hydrological queries that rely on accurate isotopic information on plant source/xylem water.  相似文献   
110.
风热流浸膏解热镇痛和抗炎作用的实验研究   总被引:1,自引:0,他引:1  
目的观察风热流浸膏的抗炎、镇痛和解热作用。方法采用二甲苯致小鼠耳肿胀、角叉菜胶致大鼠足趾肿胀的模型观察抗炎作用;采用乙酸和热刺激致小鼠疼痛的模型观察镇痛作用;采用2,4-二硝基酚和酵母粉致大鼠发热的模型观察解热作用。结果风热流浸膏能减轻小鼠耳肿胀和大鼠足趾肿胀炎症反应,缓解乙酸和热刺激所致疼痛,降低2,4-二硝基酚和酵母粉致大鼠发热的体温。结论风热流浸膏具有显著的抗炎、镇痛和解热作用。  相似文献   
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