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81.
BACKGROUNDS: Until today, human stomach is the only recognized habitat of Helicobacter pylori. However, recruitment of DNA-based methods has made possible the detection of H. pylori in water and oral cavity, thus suggesting fecal-oral and oral-oral routes for transmission of H. pylori, respectively. In this study, yeast has been proposed as a common vector for transmission of H. pylori. Thus designed primers were recruited to target 16S rDNA and cagA genes in the oral yeasts by PCR. MATERIALS AND METHODS: Eighteen yeasts were examined microscopically for the presence of bacterial-like bodies. DNAs were extracted from oral yeasts using phenol-chloroform method. Amplification conditions were optimized as 33 cycles and annealing temperatures of 63 degrees C for 16S rDNA and 51 degrees C and 52 degrees C for cagA gene which was targeted in two steps. DNAs of H. pylori and Saccharomyces cerevisiae were used as controls. Polymerase chain reaction (PCR) products of two genes from one yeast and from H. pylori were cloned in pCAP and subsequently subcloned in pSK+ and were sequenced. RESULTS: Bacterial-like bodies were observed in all oral yeasts. The amplified products of 16S rDNA from all oral yeasts were homologous in size with those of H. pylori. Fifteen out of eighteen (83%) yeasts contained cagA gene, homologous to H. pylori. CagA was not amplified from three yeasts and S. cerevisiae. Analysis of the sequenced products of 16S rDNA and cagA from one oral yeast showed 98% homology with those of H. pylori. CONCLUSIONS: The presence of H. pylori inside the yeast was indicated by light microscopy and PCR. It appears that yeasts, which are abundant in nature and thrive the mucosal surfaces of human, might serve as reservoirs and vehicles of H. pylori.  相似文献   
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Cousinia brevicaulis is described and illustrated as a new species from eastern Iran. This species belongs to the C. sect. Lasiandra Bunge as defined by hairy anther tube, yellow, pale yellow or rarely milky flowers, monocarpic growth form and corymbose branching of stem. It is easily distinguished from other species of the section by its very short‐stemmed habit. The new species is distributed in the same region as other species of C. sect. Lasiandra.  相似文献   
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Seed micromorphology in 22 species, capsule surface in 28 species and capsule hairs in 20 species of genus Verbascum distributed in Iran were studied using scanning electron microscopy. The seed surface is ridged or alveolate among the studied species. Depth and density of the alveoli or ridges, size of polygonal cells along with arrangement of vesicles on the walls separating the polygonal cells on the seed surface seem to be species-specific in Verbascum. The capsule surface is striate, distinctly or indistinctly, or even smooth in Verbascum. The capsules are rarely glabrous (in V. orientale and V. intricatum), densely covered by branched hairs, or loosely by glandular hairs, depending on species. From the results of this study it is obvious that no correlation exists between the studied species concerning the micromorphological aspects studied here.  相似文献   
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Radiation and Environmental Biophysics - Different types of DNA damages caused by ionizing radiation may enhance the cancer risk in exposed individuals. Inherited variations in DNA repair genes...  相似文献   
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Diabetes is now regarded as a major public health problem. The number of patients is estimated to increase to over 439 million cases by 2030. One of the major health clinical problems in patients with diabetes patients is impaired wound healing. Diabetic foot ulcer is a major complication of diabetes mellitus in 12 to 25% of patients, which increases the risk of damage in the limbs or amputation. The earthworm Eisenia foetida glycolipoprotein (as known G‐90) is a blend of macromolecules with some biological properties including mitogenicity, anticoagulation, fibrinolysis, bacteriostatic and antioxidatiaon. Given the biological properties of G‐90, this study was conducted to investigate the effect of extract obtained from the homogenate of Eisenia foetida (G‐90) on the wound healing process in alloxan‐induced diabetic rats. The results of the present study revealed that treatment by using G‐90 can speed up the wound healing process, which is exactly similar to the effect of D‐panthenol treatment in rats. These findings also demonstrated that G‐90 treatment decreases the risk of infection in the wound site compared with D‐panthenol treatment. In addition, histological analysis indicated that a better extracellular matrix formation with increased fibroblast proliferation, neovascularization, collagen synthesis and early epithelial layer formation was observed in G‐90 treated group. Therefore, the G‐90 could be considered as a new wound healing agent introducing promising therapeutic approaches in both human and veterinary medicine. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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The cytosolic (group IV) phospholipase A2 (cPLA2s) family contains six members. We have prepared recombinant proteins for human α, mouse β, human γ, human δ, human ϵ, and mouse ζ cPLA2s and have studied their interfacial kinetic and binding properties in vitro. Mouse cPLA2β action on phosphatidylcholine vesicles is activated by anionic phosphoinositides and cardiolipin but displays a requirement for Ca2+ only in the presence of cardiolipin. This activation pattern is explained by the effects of anionic phospholipids and Ca2+ on the interfacial binding of mouse cPLA2β and its C2 domain to vesicles. Ca2+-dependent binding of mouse cPLA2β to cardiolipin-containing vesicles requires a patch of basic residues near the Ca2+-binding surface loops of the C2 domain, but binding to phosphoinositide-containing vesicles does not depend on any specific cluster of basic residues. Human cPLA2δ also displays Ca2+- and cardiolipin-enhanced interfacial binding and activity. The lysophospholipase, phospholipase A1, and phospholipase A2 activities of the full set of mammalian cPLA2s were quantified. The relative level of these activities is very different among the isoforms, and human cPLA2δ stands out as having relatively high phospholipase A1 activity. We also tested the susceptibility of all cPLA2 family members to a panel of previously reported inhibitors of human cPLA2α and analogs of these compounds. This led to the discovery of a potent and selective inhibitor of mouse cPLA2β. These in vitro studies help determine the regulation and function of the cPLA2 family members.  相似文献   
90.
Biological Trace Element Research - This investigation was conducted to determine the effects of chromium supplementation on metabolic status in diabetic patients with coronary heart disease (CHD)....  相似文献   
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