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71.
Serological data indicate that hepatitis C virus (HCV) infection is very common among chronic hemodialysis (HD) patients. Circumstantial evidence suggests that hemodialysis per se is an important risk factor for this infection. We used a novel methodology, the branched DNA (bDNA) signal amplification assay, which is capable of detecting HCV RNA and of quantifying HCV viral load in serum, to prospectively determine the rate of acquisition of HCV infection in 274 anti-HCV-negative patients undergoing HD treatment in four hemodialysis units. Moreover, we used bDNA testing to analyze the dynamics of HCV acquisition among HD patients, a high-risk group for HCV infection with immune compromise conferred from uremia. Two patients were identified with de novo acquisition during 1 year of prospective bDNA testing. Thus, the HCV incidence was 0.73% per year. De novo acquisition of HCV infection was observed in the absence of identifiable parenteral risk factors. Both patients showed the same pattern of HCV acquisition: they underwent an initial viremic phase that was associated with an increase in alanine transaminase (ALT) activity and that preceded the anti-HCV seroconversion. This was followed by HCV RNA clearance and normalization of ALT activity. Anti-HCV positivity occurred 1 and 2 months after the ALT increase in the first and second patients, respectively. Although HCV incidence was low (0.73%), further research is warranted to set the optimal policy for eliminating the risk of nosocomial transmission of HCV in the HD setting. Our findings show the pattern of HCV acquisition in chronic HD patients and emphasize the need to screen the HD population for ALT measurement combined with anti-HCV testing for detecting hepatitis C. HCV RNA testing can identify HCV before seroconversion in individuals with deranged liver function tests. The acquisition of HCV in HD patients without identifiable risk is confirmed.  相似文献   
72.
We carried out this investigation to examine the effects on angiogenesis-mediated processes and to define anti-angiogenesis mechanisms for flavonoids. We examined the effects and mechanisms of the flavonoid resveratrol on angiogenesis and tumor growth using the chick chorioallantoic membrane (CAM) model of angiogenesis, the CAM tumor growth model, and the effect on p53 in fibroblast growth factor-2 (FGF2) stimulated human endothelial cells using immunoassay. Resveratrol demonstrated potent inhibition (effective dose50=0.7+/-0.1 microM) of FGF2-induced angiogenesis and tumor growth. Furthermore, resveratrol significantly (P<0.01) inhibited platelet/fibrin clot-promoted human colon and fibrosarcoma tumor growth in the CAM tumor model. Resveratrol in a concentration-dependent (1-3 microM) manner significantly promoted apoptosis in FGF2-stimulated endothelial cells by increasing p53 protein production. These data indicated potent anti-angiogenesis efficacy, inhibition of tumor growth, and clot-mediated enhanced tumor growth. These data suggest potential anticancer benefits as a chemopreventive and chemotherapeutic for the flavonoid resveratrol.  相似文献   
73.
Background: During hemorrhagic hypotension, sympathetic vasoconstriction crucially contributes to gut mucosal damage. Sympathetic blockade by thoracic epidural anesthesia has been shown to increase mucosal microvascular perfusion and to improve survival after severe hemorrhage in laboratory animals. This study investigates the effects of thoracic epidural anesthesia on intestinal microvascular perfusion during hemorrhagic hypotension in rats.

Methods: In 32 anesthetized Sprague-Dawley rats either lidocaine 2% (thoracic epidural anesthesia) or normal saline (control) was infused via thoracic epidural catheters. Hemorrhagic hypotension (mean arterial pressure 30 mmHg for 60 min) was induced by withdrawal of blood, which was subsequently retransfused for resuscitation. Functional capillary density and erythrocyte velocity in the mucosa and muscularis were determined by intravital microscopy. Leukocyte-endothelium interaction was studied in postcapillary venules and sympathetic nerve fibers of the intestinal wall were identified by immunohistochemistry.

Results: During hypotension functional capillary density was significantly (P < 0.001) lower in the muscularis of the control group (median [25/75 percentile]: -46.5% [-59.6/-20.8%] change from baseline) as compared with animals that received thoracic epidural anesthesia (-6.1% [-13.4/1.1%]). There were no differences in erythrocyte velocity between groups throughout the experiment. Leukocyte rolling increased significantly (P < 0.001) after resuscitation in control (12 [6/15]vs. baseline 2.5 [1/8]) but not in thoracic epidural anesthesia (4 [2.3/7]vs. baseline: 5 [3/15.5]). Sympathetic nerve fibers were identified in the muscularis and submucosa but not in the mucosa.  相似文献   

74.
75.
A middle-aged male resident of Benghazi, northeastern Libya, with radiological features of skeletal fluorosis associated with cervical radiculomyelopathy is reported. This is believed to be the first documentation of such a disorder from this non-tropical, non-endemic region.  相似文献   
76.
First admission rates to the psychiatric hospital in Kuwait revealed that foreign housemaids as a whole had about five times the rate of Kuwaiti females. According to hospital diagnoses the housemaids had significantly more acute situational disturbances and mania, and less depressive illness and organic mental disorders. Regarding schizophrenia and paranoid state there was no significant difference between the two groups. It is recommended that good interpreters should be appointed as part of an appropriate staffing of the psychiatric hospital.  相似文献   
77.
Generation of free radicals in kidney cortex plays an important role in the pathogenesis of gentamicin (GM) nephrotoxicity, and curcumin, the yellow curry pigment isolated from turmeric, has been confirmed to have a strong antioxidant action. Therefore, in the present work, we aimed at testing the possible protective or palliative effect of curcumin on GM nephrotoxicity. Curcumin was given to rats at an oral dose of 200 mg/kg/day for 10 days, and in some of these rats GM was also injected intramuscularly at a dose of 80 mg/kg/day during the last 6 days of the treatment. Nephrotoxicity was evaluated histopathologically by light microscopy, and biochemically by measuring the concentrations of creatinine and urea in serum, and reduced glutathione (GSH) concentration and superoxide dismutase (SOD) activity in renal cortex. The concentration of GM in renal cortex was measured microbiologically. GM significantly increased the concentrations of urea and creatinine (P < 0.05) by about 111 and 97%, respectively. GM treatment reduced cortical GSH concentration by about 31% (P < 0.05), and the activity of SOD by about 27% (P < 0.05). Curcumin significantly mitigated these effects. Sections from saline and curcumin-treated rats showed apparently normal proximal tubules. However, kidneys of GM-treated rats had a moderate degree of necrosis. The degree of necrosis appeared lessened when GM was given simultaneously with curcumin. The concentration of GM in the renal cortex of the rats given GM + curcumin was significantly (P < 0.05) lower than that found in rats treated with GM alone by about 39%. The results suggested that curcumin had ameliorated the histopathological and biochemical indices of nephrotoxicity in rats. Pending further studies, curcumin may potentially be useful as a nephroprotectant agent.  相似文献   
78.
Pulmonary hypertension is a disorder characterized by an increase in mean pulmonary arterial pressure (mPAP > 25 mmHg), which is responsible for the transport of blood from the heart to the lungs. Increased pressure leads to decreased flow of blood through the lungs and decreased oxygen deliverance throughout the body. The disorder causes right ventricular hypertrophy and can quickly lead to death, especially with the severe forms of pulmonary hypertension. Symptoms include fatigue, shortness of breath, dizziness and peripheral edema in the lower extremities. Symptoms are usually delayed in appearance and progress slowly, which leads to a late diagnosis and often a poor prognosis. Despite large advances in the last 10 years, there is still about a 15% annual mortality for diagnosed patients. Despite the number of medications available, there are still no cures for this fatal disease. Current therapies include endothelin receptor antagonists, prostacyclin agonists and cGMP-specific 3',5'-cyclic phosphodiesterase (PDE5) inhibitors or combinations. Recent strategies have shown promise in animal models to prevent the onset of pulmonary hypertension when it is induced. However, few of them show a sustained benefit in clinical trials. Strategies for the cure of this debilitating disease should be the focus of future research.  相似文献   
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80.
The purpose of this paper is to describe our experience with a new technique of colonic manometry catheter placement using fluoroscopic guidance. Between 2000 and 2004, 44 colonic manometry catheters were placed with primary fluoroscopic guidance in 38 patients (25 males; median age, 7 years; range, 0.4–31 years) with severe defecation disorders. Fourteen colonoscopic placements were reviewed to compare the different procedures. Manometry catheters were inserted through the rectum (16 patients), cecostomy (9), ileostomy (2), and colostomy (17). Placements through diverted colons were successful in 24 of 28 (86%). Insertion through the rectum was successful in 10 of 16 (63%) fluoroscopic-guided placements vs. 12 of 14 (86%) colonoscopic placements (P=0.23). Significantly longer fluoroscopic exposure was required for fluoroscopic compared to colonoscopic placement (P=0.004). In conclusion, placement of colonic manometry catheters with primary fluoroscopic guidance is feasible in children. An important disadvantage of the fluoroscopic methodology is the prolonged fluoroscopic exposure time.  相似文献   
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