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71.
Neonatal sepsis is a disease of infants who are less than 1 month of age. These infants are clinically ill, and their blood culture are positive for bacteria. The reported incidence of neonatal sepsis for all infants is 1 to 10 per 1000 live births. The mortality rate is 4.2-26%. The clinical signs are not specific and diagnosis of neonatal sepsis is one of the most difficult tasks in clinical medicine. The aim of this work was determination of CD11b sensitivity and specificity for early detection of neonatal sepsis. We studied 65 neonates with gestational age of 27 to 38 weeks who were suspected for sepsis within the 28 days of life. Whole blood was obtained from neonates to determine CD11b expression on peripheral blood neutrophils by flow cytometry. C-Reactive protein (CRP) was measured qualitatively. Neonates were divided into two groups. Classification was based on the result of the blood culture. In the sepsis group all of the neonates (n=8) showed positive blood culture and clinical symptoms. In the suspected group (n=57) the neonates showed clinical signs but blood cultures were negative. Sensitivity and specificity of CD11b were 75%, 100% respectively. Also positive and negative predictive values of CD11b were 100% and 86% respectively. Results of present study and previous studies showed that measurement of neutrophil surface markers can be useful for diagnosis of infection in the early phases. Also, the quantitative measurement of CRP in addition to CD11b further enhances the ability to diagnose infections and improves sensitivity and negative predictive value by 100%.  相似文献   
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The mechanism of lithium action, an effective treatment for bipolar disease, is still unknown. The present study examined the role of nitric oxide (NO) and prostaglandin systems in lithium modulation of acetylcholine in mesenteric vascular bed of rats by cannulating superior mesenteric artery. Acetylcholine (ACh) or sodium nitroprusside was injected under constant controlled flow induced by phenylephrine; therefore, changes in perfusion pressure reflect changes in resistance. Although 0.5 mM or 1 mM lithium-pretreatment of vascular bed causes reduction in ACh-response, 1.5 mM lithium induced no changes and 2 and 2.5 mM lithium potentiated ACh-induced mesenteric vascular bed relaxation compared to control group. Pretreatment of vascular bed with L-NAME or indomethacin decreased ACh-induced relaxation in 2 concentrations of 0.5 and 2 mM of lithium. The vasorelaxation response to sodium nitroprusside, the NO donor, was not different among lithium groups (0.5 and 2 mM) and controls. In conclusion, there is a dual modulation of endothelium-dependent relaxation, including an inhibitory effect at lower dose and a stimulating effect at higher dose of lithium in rat mesenteric vascular bed. NO synthesis or cyclooxygenase inhibition decreased vasorelaxation in both lower and higher doses of lithium, suggesting a role for NO and prostaglandin in this effect.  相似文献   
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OBJECTIVE: To verify the effect of chronic lithium administration on the endothelium-dependent relaxation of rat corpus cavernosum, as lithium is a major drug for treating bipolar disorder and some studies showed that lithium might cause erectile dysfunction in such patients, by a mechanism as yet unknown. MATERIALS AND METHODS: LiCl (600 mg/L) was dissolved in drinking water and Sprague-Dawley rats received the solution for 30 days; control rats received tap water. After 30 days corporeal strips were prepared from both groups, mounted under tension in oxygenated organ baths, and pre-contracted with phenylephrine (7.5 microm). After equilibration, the strips were relaxed by acetylcholine (10 nm to 1 mm) in the presence or absence of indomethacin (a cyclooxygenase inhibitor; 20 microm). Furthermore, the relaxant responses to sodium nitroprusside (1 nm to 1 mm), a nitric oxide (NO) donor, were investigated in both groups. NADPH-diaphorase histochemistry was used to identify NO synthase within cavernosal tissue strips of both groups. RESULTS: The acetylcholine-dependent relaxation was significantly lower in lithium-treated rats than in controls. Although indomethacin decreased significantly the relaxant responses to acetylcholine in controls, it increased the relaxant responses in lithium-treated rats. NADPH-diaphorase staining was greater in the chronic lithium-treated than in control preparations. Sodium nitroprusside produced similar relaxation in both groups. CONCLUSION: Chronic lithium administration can impair the endothelium-dependent relaxation of rat corpus cavernosum; NO availability might decrease after lithium administration and the cyclooxygenase pathways might have a role in this effect.  相似文献   
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Tuberculosis is a chronic mycobacterial infection. The main effector cells against mycobacterium tuberculosis are CD4+ T lymphocytes. Our objective in this research was to evaluate the quantity of T lymphocytes and their subpopulations before and after treatments with combination of 4 drugs (Rifampcin, Isoniaside, pyrasinamide, Ethambutal) for 2 months directly in sputum-positive tuberculosis patients. Twenty patients as cases and twenty healthy people were selected as controls. Flow cytometry was used for TCD3+, TCD4+ and TCD8+ lymphocytes by using monoclonal antibodies. Our results indicated that there was alteration in cell mediated immunity during tuberculosis showing itself as decrease in TCD3+ and TCD4+ lymphocytes and increase in TCD8+ lymphocytes. The changes in TCD3+ and TCD4+ but not in TCD8+ were reversible after 2 months of treatment.  相似文献   
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Even though the mechanical heart valve (MHV) has been used routinely in clinical practice for over 60 years, the occurrence of serious complications such as blood clotting remains to be elucidated. This paper reviews the progress that has been made over the years in terms of numerical simulation method and the contribution of abnormal flow toward blood clotting from MHVs in the aortic position. It is believed that this review would likely be of interest to some readers in various disciplines, such as engineers, scientists, mathematicians and surgeons, to understand the phenomenon of blood clotting in MHVs through computational fluid dynamics.  相似文献   
80.
Kidney transplant recipients are susceptible to various infections due to the use of immunosuppressive drugs. The present study was performed as studies on the prevalence of intestinal fungal and parasitic infections in kidney transplant recipients are limited. A total of 150 kidney transplant recipients and 225 matched immunocompetent outpatients, who were referred to the laboratory of Noor Hospital, Isfahan, were studied. After recording demographic characteristics, direct test and specific laboratory cultures were carried out on the stool specimens. Patients were instructed on sanitary rules and, during each medical visit, they were reminded of the same. The overall prevalence of intestinal parasitic and fungal infections was 33.3% and 58.7%, respectively, in transplant recipients and 20% and 51%, respectively, in the control group; the difference was not statistically significant. The most prevalent intestinal parasite was Entameba coli, which was seen in 9.3% of the study patients and 6.7% of the controls. The most prevalent fungus was Candida sp., which was seen in 22% of the study patients and 24.4% of the control group. Co-existing infection with two or more fungi was seen in 14.8% and 3.4% in the case and control groups, respectively; P <0.001. Interestingly, there was no significant difference in the prevalence of infection by a single organism between the two groups. However, co-existing infection with two or more species was more prevalent in transplant recipients. We conclude that further investigations are needed to evaluate the pathogenesis of infection with these microorganisms.  相似文献   
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