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11.
人尿中几种雄激素及蛋白同化激素的HPLC测定   总被引:3,自引:0,他引:3  
毕红钢  周同惠 《药学学报》1989,24(3):207-211
对HPLC分离及定量测定人尿中雄激素及蛋白同化激素的方法进行了初步研究。确定了六种甾体激素的分离条件及内标定量方法。固定相为C8键合硅胶,甲醇—乙腈—水(4:5:6)恒溶剂洗脱,程序流速。紫外检测器波长254 nm。检测限可至1 ng以下。本法采用Sep-Pak C18小柱进行尿样净化,回收率高而且稳定。操作简便快速。对尿样中甾体葡萄糖醛酸甙结合物的酶促水解条件也进行了初步探索。  相似文献   
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Background Glutathione peroxidase (GPx) protects cells from oxidative damage by catalyzing the reduction of both organic and hydrogen peroxides, using glutathione as a reducing agent. Both plasma GPx (P-GPx) and erythrocyte GPx (E-GPx) have been identified in human blood. Kidney proximal tubular cells are the main source of GPx activity in the plasma. Oxidative damage has been reported to participate in the progression and complications of renal diseases.Methods The activities of both E-GPx and P-GPx were determined, using Randox commercial kits, in 12 patients with nephrotic syndrome (NS), 48 patients with renal impairment (RI), and 50 patients with chronic renal failure on maintenance hemodialysis (HD; before as well as immediately after dialysis), and in 50 healthy volunteers who served as controls.Results Compared to the results in healthy controls, P-GPx activity was reduced in the HD group and the RI group, whereas the NS group showed no significant difference from the control. The HD group showed a higher drop in P-GPx (reduced to 36.6% of the mean control value) than the RI group (reduced to 61.8% of the mean control value). Further analysis of the RI group showed a highly significant negative correlation between P-GPx activity and serum creatinine level (r = −0.691; P < 0.001). Also, a highly significant negative correlation was found between P-GPx and blood urea nitrogen (r = −0.792; P < 0.001). However, E-GPx activity showed no significant correlation with either serum creatinine or blood urea nitrogen.E-GPx was reduced to 55.2% and 68.9% of the mean control 1 value in the NS group and the RI group respectively, while the HD group showed no significant change. Further analysis of the RI group found that E-GPx activity showed no significant correlation with either serum creatinine or blood urea nitrogen. In HD patients, GPx activity was measured before and immediately after hemodialysis. E-GPx activity was similar before and after dialysis, without a significant difference (pre-dialysis, 37.7 ± 13.5 U/g hemoglobin [Hb]; post-dialysis, 38.72 ± 12.31 U/g Hb). However, P-GPx activity was significantly increased (pre-dialysis, 254.4 ± 62.6 U/ml; post-dialysis, 296.98 ± 74.04 U/ml; P < 0.001), but it was still significantly lower when compared to that in the healthy controls.Conclusions P-GPx activity is an important test to assess the oxidative damage in patients with kidney diseases. The progression of renal disorders is accompanied by a decrease in P-GPx activity, but not by a decrease in E-GPx activity. Thus, we conclude that P-GPx activity largely depends on physiological renal function, whereas E-GPx activity does not.  相似文献   
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Background: Primary healthcare (PHC) is essential for equitable access and cost-effective healthcare. This makes PHC a key factor in the global strategy for universal health coverage (UHC). Implementing PHC requires an understanding of the health system under prevailing circumstances, but for most countries, no data are available.

Objectives: This paper describes and analyses the health systems of Bahrain, Egypt, Lebanon, Qatar, Sudan and the United Arab Emirates, in relation to PHC.

Methods: Data were collected during a workshop at the WONCA East Mediterranean Regional Conference in 2017. Academic family physicians (FP) presented their country, using the WONCA framework of 11 PowerPoint slides with queries of the country demographics, main health challenges, and the position of PHC in the health system.

Results: All six countries have improved the health of their populations, but currently face challenges of non-communicable diseases, aging populations and increasing costs. Main concerns were a lack of trained FPs in community settings, underuse of prevention and of equitable access to care. Countries differed in the extent to which this had resulted in coherent policy.

Conclusion: Priorities were (i) advocacy for community-based PHC to policymakers, including the importance of coordination of healthcare at the community level, and UHC to respond to the needs of populations; (ii) collaboration with universities to include PHC as a core component of every medical curriculum; (iii) collaboration with communities to improve public understanding of PHC; (iv) engagement with the private sector to focus on PHC and UHC.  相似文献   
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A novel series of 1,3,5-triazine analogs was successfully synthesized through conjugation with benzimidazole or 1,2,4-triazole derivatives via a methylenethio linker. The new analogs were in vitro evaluated against HSV-1 in Vero cells; among these analogs, two compounds exhibited good effect in inhibiting HSV-1 replication (for compound 5p: EC50 = 3.5 μg/ml, SI = 358; for compound 5r: EC50 = 5.0 μg/ml, SI = 300) in comparison to acyclovir.  相似文献   
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Effect of squalamine on iris neovascularization in monkeys   总被引:3,自引:0,他引:3  
PURPOSE: To investigate the effect of squalamine, an antiangiogenic aminosterol, in an experimental model of iris neovascularization. METHODS: Iris neovascularization was created in cynomolgus monkeys by occluding retinal veins with an argon laser and inducing persistent hypotony with a central corneal suture. Twenty-four eyes were treated in three groups. In Group 1, four eyes were injected intravitreally with 3 microg/0.1 mL squalamine and four eyes with balanced saline solution (controls) immediately after vein occlusion (day 1); injections were repeated every 3 days for 3 weeks. In Group 2, 1 mg/kg squalamine was administered with intravenous infusion in dextrose 5% in four animals; four control animals received only dextrose. Infusions began on day 1 and were repeated every 3 days for 3 weeks. In Group 3, after development of iris neovascularization on day 7, 1 mg/kg squalamine was injected systemically in four animals; four control animals received dextrose 5%. Monkeys were examined by slit-lamp biomicroscopy and underwent color photography and fluorescein angiography. RESULTS: Group 1: All eyes, treated and control, developed intense and persistent rubeosis iridis. Group 2: Two of the four treated eyes in this group developed minimal iris neovascularization; the other two had no iris neovascularization. All four control eyes developed intense, persistent iris neovascularization. Group 3: All eyes developed extensive rubeosis iridis; iris neovascularization regressed in all four treated eyes after squalamine injections. Two of four treated eyes retained minimal iris neovascularization; two showed complete regression of rubeosis iridis. Rubeosis iridis completely regressed in two of the four control eyes; the remaining two control eyes had intense, persistent iris neovascularization. CONCLUSIONS: Intravitreally injected squalamine did not affect the development of iris neovascularization; however, systemic squalamine injection inhibited the development of iris neovascularization and caused partial regression of new vessels in a primate model.  相似文献   
18.
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
19.
A total number of selected 252 patients with prolapsed lumbar intervertebral discs (92 extruded and 160 protruded) were operated upon in Neurosurgery Department Zagazig University Hospital during the period extended from January, 1988, to October 1990. In this study we reviewed their clinical and operative data. Surgical biopsies were taken from randomly selected 120 patients of them (50 extruded and 70 protruded discs) and were subjected to histopathological, histochemical and immunopathological studies. Ultrastructural study was performed for randomly selected 14 cases (7 extruded and 7 protruded discs). The results were compared with 7 normal intervertebral discs obtained from these studies showed that there were no differences between extruded and protruded discs at the histochemical level. Cell mediated immunity could be added as a factor in the pathogenesis of the degenerative process that lead to disc prolapse (in 20% of cases with extruded discs and 57.1% of cases with protruded discs). At the ultrastructural level 85.3% of extruded discs were prolapsed nucleus pulposus while 14.7% were prolapsed annulus fibrosus alone or with nucleus pulposus. All protruded discs were prolapsed annulus fibrosus with nucleus pulposus. These findings may have an impact on the management of this common problem.  相似文献   
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The effect of piroxicam on the blood-retina barrier was evaluated in rats with experimentally induced diabetes. Diabetes was induced in rats by intraperitoneal injection of streptozocin (STZ). Diabetic rats were divided into two equal groups: those treated with piroxicam, a long-acting platelet inhibitor, and an untreated control group. Vitreous fluorophotometry (VFP) was performed both before and two weeks after induction of diabetes and piroxicam intake. Streptozocin-induced diabetes caused an alteration in the blood-retinal barrier evidenced by an increase in vitreous fluorescein concentration in diabetic rats compared with normal rats. Piroxicam intake did not lead to significant change in vitreous fluorescein concentrations. However, the examination had to be terminated at two weeks because of cataract formation. The piroxicam treated group showed less incidence of lens opacity formation (59.1% compared to 81.8% in the untreated group, p = 0.0006). Piroxicam administration appears to protect the diabetic rat eye against lens opacification.This work was supported in part by U.S. Public Health Service Grants EY02377, EY07541 and EY08137 from the National Eye Institute, National Institutes of Health, Bethesda, MD and by the Juvenile Diabetes Foundation International and Pfizer, Inc.  相似文献   
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