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81.
A comparative analysis of the laser and electromagnetic laser therapy was performed in the complex treatment of patients with obliterating atherosclerosis of the lower extremity vessels. Laser treatment exerts a therapeutic effect related with its influence upon microcirculation. The effectiveness of complex treatment becomes higher when using a combination of laser therapy with the impulse electromagnetic therapy of complex modulation at the expense of improvement of the regional blood circulation in all links of the vasculature.  相似文献   
82.
The dipeptidyl epoxy ketone 4 is a potent, irreversible inhibitor of cruzain, a cysteine protease isolated from Trypanosoma cruzi, with an apparent second order inhibition rate constant of 330,000 sec-1M-1.  相似文献   
83.
Novel polyamides were developed that can be used as cross-linking agents for proteins such as hemoglobin. Water-soluble, nonimmunogenic polyamides containing oxygen and sulfur atoms in the backbone were prepared by the polycondensation of the diacids bis(carboxymethyloxyacetyl)-1,4-diaminobutane (1a) or 3, 3'-thiodipropionic acid (1b) with diethylene glycol bis(3-aminopropyl) ether (2). The resulting alpha,omega-diacids were converted to the corresponding activated esters using any of a variety of carboxylic acid activating reagents including the novel reagent diphenyl(1-methylimidazol-2-thiyl)phosphonate (9). The resulting polyamides could be activated with a broad spectrum of groups that allow for the cross-linking and surface modification of proteins.  相似文献   
84.
虚拟现实技术是当今世界最前沿的技术之一,虚拟实验室是虚拟现实技术在教育领域的应用.本文首先介绍了几种构建虚拟实验室的方法以及它们的优缺点,然后提出了一种基于Virtools的虚拟实验室的构建方法.本文把这种构建方法分为三个步骤,即构建模型、交互功能设计和虚拟实验室的发布.最后提出了在构建过程当中遇到的一些关键问题及其解...  相似文献   
85.
A high incidence of feather follicle infection was observed in broilers reared in cages with wood slat floors. The incidence of feather follicle infection was significantly higher for males than for females within cage-reared broilers at 59 days of age. Male broilers at 50 days of age had a significantly lower incidence of the feather follicle condition than hatch mates at 59 days of age. Intact feather follicles were removed from freshly killed cage-reared birds and prepared for scanning electron microscopy (SEM). Examination of infected follicles revealed surface detail about the lesions. Removal of the encrustations covering the infected follicles revealed numerous cocci type bacteria at the base of the follicle. Infected and non-infected follicles were also examined by conventional histological techniques. Gram positive cocci were observed at the base of the infected follicles.  相似文献   
86.
A patient with a choledochal cyst presenting solely with abdominal pain is described. The cyst was diagnosed by endoscopic retrograde cholangiography. The clinical, radiographic, and surgical features of this disorder are briefly reviewed and the need to consider this entity as a possible cause of obscure abdominal pain is stressed.  相似文献   
87.
Interleukin-2 (IL-2) is a potent T cell mitogen. However, the signaling pathways by which IL-2 mediates its mitogenic effect are not fully understood. One of the members of the mitogen-activated protein kinase (MAPK) family, p42/44MAPK (ERK2/1), is known to be activated by IL-2. We have now investigated the response to IL-2 of two other members of the MAP kinase family, p54MAP kinase (stress-activated protein kinase (SAPK)/Jun-N-terminal kinase (JNK)) and p38MAP kinase (p38/Mpk2/CSBP/RK), which respond primarily to stressful and inflammatory stimuli (e.g. tumor necrosis factor-alpha, IL-1, and lipopolysaccharide). Here we show that IL-2, and another T cell growth factor, IL-7, activate both SAPK/JNK and p38MAP kinase. Furthermore, inhibition of p38MAP kinase activity with a specific pyrinidyl imidazole inhibitor SB203580 that prevents activation of its downstream effector, MAPK-activating protein kinase-2, correlated with suppression of IL-2- and IL-7-driven T cell proliferation. These data indicate that in T cells p38MAP kinase has a role in transducing the mitogenic signal.  相似文献   
88.
The CXCR4 chemokine receptor has been shown to respond to the C-X-C chemokine stromal-derived factor (SDF-1) and has recently been shown to be an important coreceptor for HIV-1 infection. In the present paper we have tested a number of human lymphocyte cell lines, including Jurkat, HUT78, CEM, and Sup-T1 for the presence of CXCR4 receptors. We found that these T cell lines bind SDF-1alpha and SDF-1beta with high affinity. The CXCR4 Ab 12G5 inhibited both SDF-1 binding and HIV-1LAI-mediated fusion of CEM. Scatchard analysis revealed the presence of approximately 150,000 SDF-1alpha-binding sites per cell with a Kd between 5 and 10 nM. Cross-competition experiments using unlabeled SDF-1alpha and SDF-1beta revealed that both chemokines are equally capable of displacing their radiolabeled counterparts. Internalization studies with [125]I-SDF-1alpha revealed that Jurkat cells internalized greater than 90% of the ligand by 2 h at 37 degrees C. SDF-1alpha was also chemotactic for Jurkat cells and caused an increase in the rate of extracellular acidification that was half-maximal at 18 nM SDF-1alpha and could be inhibited by pretreatment with the SDF-1 proteins, pertussis toxin, or the Ab 12G5. Finally, SDF-1alpha also caused an increase in the cytosolic Ca2+ concentration in Sup-T1 cells that was abolished by preincubating the cells with pertussis toxin or PMA and inhibited by the Ab 12G5. This molecular characterization of CXCR4 receptors should prove useful in clarifying receptor interaction with SDF-1 proteins and with HIV-1 glycoprotein, with the ultimate aim of targeting the viral interaction for therapeutic intervention.  相似文献   
89.
Ionic currents are critical for the functioning of the inner ear auditory sensory epithelium. We set out to identify and molecularly clone the genes encoding the channels responsible for several currents in the chick basilar papilla. Here we describe an inward-rectifying K+ channel, cKir2.3, present in both hair cells and support cells in the apical end of the chick basilar papilla. The biophysical properties of the human ortholog, hKir2.3, are similar to those of an inward-rectifying channel found in the apical end of the chick basilar papilla, suggesting that this channel may contribute to the corresponding current. Additionally, we describe two new members of the Kv6 subfamily of putative regulatory voltage-gated K channels, cKv6.2 and cKv6.3. Both are expressed in hair cells in the apical end of the chick basilar papilla; cKv6.2 is also strongly expressed in support cells and in the brain.  相似文献   
90.
This study was undertaken to investigate the use of maximum intensity projection (MIP) images in the detection of pulmonary nodules by spiral CT (SCT). 40 pulmonary nodules of high density were created by endobronchial deployment of 2 and 4 mm beads in the peripheral airways of five anesthetized dogs. Standard SCT was performed with 5 mm collimation, pitch 2 and reconstruction of contiguous slices. MIP images were generated from overlapped slabs of seven consecutive 3 mm slices, reconstructed at 2 mm intervals and acquired at pitch 2. Scans were reviewed by six radiologists. The data were modelled using ordinal logistic regression for repeated measures, and the Wald chi 2 statistic used to test if there was a difference in nodule detection and reader confidence level between the two techniques. MIP imaging increased the odds of nodule detection by 2.18 (p = 0.0002). Reader confidence level for nodule detection was significantly higher with MIP images (p < 0.00001). MIP images improve the detection rate for small high density pulmonary nodules and increase reader confidence level, when compared with standard SCT.  相似文献   
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