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81.
Behavioral studies have suggested that exaggerated reactivity to food cues, especially those associated with high-calorie foods, may be a factor underlying obesity. This increased motivational potency of foods in obese individuals appears to be mediated in part by a hyperactive reward system. We used a Philips 3T magnet and fMRI to investigate activation of reward-system and associated brain structures in response to pictures of high-calorie and low-calorie foods in 12 obese compared to 12 normal-weight women. A regions of interest (ROI) analysis revealed that pictures of high-calorie foods produced significantly greater activation in the obese group compared to controls in medial and lateral orbitofrontal cortex, amygdala, nucleus accumbens/ventral striatum, medial prefrontal cortex, insula, anterior cingulate cortex, ventral pallidum, caudate, putamen, and hippocampus. For the contrast of high-calorie vs. low-calorie foods, the obese group also exhibited a larger difference than the controls did in all of the same regions of interest except for the putamen. Within-group contrasts revealed that pictures of high-calorie foods uniformly stimulated more activation than low-calorie foods did in the obese group. By contrast, in the control group, greater activation by high-calorie foods was seen only in dorsal caudate, whereas low-calorie foods were more effective than high-calorie foods in the lateral orbitofrontal cortex, medial prefrontal cortex, and anterior cingulate cortex. In summary, compared to normal-weight controls, obese women exhibited greater activation in response to pictures of high-calorie foods in a large number of regions hypothesized to mediate motivational effects of food cues.  相似文献   
82.
Summary. Background: Recent studies indicate that arterial cardiovascular diseases and venous thromboembolism (VTE) share common risk factors. A family history of myocardial infarction (MI) is a strong and independent risk factor for future MI. Objectives: The purpose of the present study was to determine the impact of cardiovascular risk factors, including family history of MI, on the incidence of VTE in a prospective, population‐based study. Patients and methods: Traditional cardiovascular risk factors and family history of MI were registered in 21 330 subjects, aged 25–96 years, enrolled in the Tromsø study in 1994–95. First‐lifetime VTE events during follow‐up were registered up to 1 September 2007. Results: There were 327 VTE events (1.40 per 1000 person‐years), 138 (42%) unprovoked, during a mean of 10.9 years of follow‐up. In age‐ and gender‐adjusted analysis, age [hazard ratio (HR) per decade, 1.97; 95% confidence interval (CI), 1.82–2.12], gender (men vs. women; HR, 1.25; 95% CI, 1.01–1.55), body mass index (BMI; HR per 3 kg m?2, 1.21; 95% CI, 1.13–1.31), and family history of MI (HR, 1.31; 95% CI, 1.04–1.65) were significantly associated with VTE. Family history of MI remained a significant risk factor for total VTE (HR, 1.27; 95% CI, 1.01–1.60) and unprovoked VTE (HR, 1.46; 95% CI, 1.03–2.07) in multivariable analysis. Blood pressure, total cholesterol, HDL‐cholesterol, triglycerides, and smoking were not independently associated with total VTE. Conclusions: Family history of MI is a risk factor for both MI and VTE, and provides further evidence of a link between venous and arterial thrombosis.  相似文献   
83.
84.
Compared to US men, US women have worse HAART and HIV health outcomes. The study examined main partner factors associated with women's HAART adherence. The community sample comprised 85% African-Americans; 63% had a main partner and 32% relied on their partner for emotional support. Adherence was highest (92%) among those without a main partner and lowest (57%) among those with an HIV seropositive main partner. In adjusted analysis, adherence was 75% less likely among women with an HIV seropositive main partner and 78% less likely among those relying on their partner for emotional support. Furthermore, HIV seropositive versus other serostatus main partners were most likely to provide medication taking assistance and to be preferred in helping participants deal with HIV, yet were no more likely to be nominated as the most helpful to them. Findings reveal women's perceived unmet support needs from HIV seropositive main partners in this population and the need for interventions to promote their HAART adherence. Seroconcordant couples-focused intervention that enhances mutual support of HAART adherence may be an effective approach to improving women's HAART adherence and reducing US gender disparities in HIV health outcomes.  相似文献   
85.
86.
When a high titre inhibitor develops in a patient with haemophilia, attempts are made to eradicate it through immune tolerance induction therapy (ITI) involving the frequent and regular administration of factor, usually for months to years. ITI is successful in only two thirds of patients prompting investigators to explore alternate regimens to use in haemophiliacs failing conventional ITI. Rituximab is an anti-CD20 monoclonal antibody, which has shown promise in the treatment of B-cell-mediated disorders. We developed a protocol for the use of rituximab in haemophilia A (HA) patients failing conventional ITI or in those haemophiliacs where the likelihood of success of conventional ITI is poor. Patients receive 375 mg m(-2) of intravenous rituximab weekly for 4 weeks followed by monthly (up to 5 months) until inhibitor disappearance and establishment of normal FVIII pharmacokinetics (recovery and half-life). Patients are concurrently placed on recombinant FVIII (100 U kg(-1) day(-1)). We have placed five haemophiliacs (four children with severe HA, and one adult with mild HA) on this protocol. In three patients (two with severe HA and one with mild HA) inhibitors disappeared although in neither severe haemophiliac did FVIII pharmacokinetics completely normalize. The fourth patient had a significant drop in inhibitor titres although not a complete disappearance of the inhibitor. All four of these patients ceased bleeding following rituximab. The fifth patient had no response to rituximab. This non-responding patient was not placed on concurrent FVIII. Our five cases suggest that rituximab may hold promise in the eradication of inhibitors. Prospective randomized studies are required to determine the value of this agent in inhibitor management.  相似文献   
87.
艾滋病合并隐球菌脑膜炎18例临床分析   总被引:6,自引:1,他引:6  
目的 提高对艾滋病 (AIDS)合并隐球菌脑膜炎的认识。方法 对赤道几内亚巴塔地区医院 18例AIDS合并隐球菌脑膜炎患者进行临床综合分析。结果  18例AIDS合并隐球菌脑膜炎患者的临床主要表现为 :发热、剧烈头痛、极度乏力、肢体痛、脑膜刺激征及消瘦与脱水等。脑脊液 (CSF)培养均为新型隐球菌生长 ;涂片及隐球菌多糖荚膜抗原 (ELISA法 )检测的阳性率分别为 77 8% (14/ 18) ,94 4% (17/ 18)。结论 隐球菌脑膜炎为AIDS常见机会性感染及主要致死病因之一。  相似文献   
88.
The genetic defect in the cardiomyopathic (CM) hamster is a mutation in the glycoprotein-sarcoglycan (a component of the dystrophin-glycoprotein complex). Apoptosis has been identified in skeletal muscle of dystrophin-deficient mice, and therefore the role of myocardial apoptosis in relation to oncosis in causing myocardial necrosis was assessed at the onset of left ventricular (LV) dysfunction in CM hamsters. LV size and function were evaluated in normal and CM hamsters (CHF147 line) by echocardiography at 1, 2, 3, and 5 months (mo) of age. The decrease of LV fractional shortening was found to be most marked (45 %) between 1 and 2 mo of age. Apoptotic nuclei were identified at each time point using in situ end-labeling of DNA strand breaks (TUNEL), together with immunolabeling of myocytes; DNA fragmentation (laddering) and nuclear morphology were also assessed. Myocyte oncotic necrosis was assessed at 2 mo by Evans blue dye (EBD), wheat germ agglutinin, hematoxylin/eosin staining, and electron microscopy. Apoptotic nuclei were not detected in age-matched normal hamsters. In the CM hamsters apoptotic myocyte nuclei comprised an average of 0.041 % of myocyte nuclei between 1 and 5 mo, an increase at 2 mo (to 0.076 %) was not significant, and DNA laddering was not detected. The number of myocyte nuclei per unit area decreased by 32 % between 1 and 2 mo, and in 2 mo old CM hamsters myocardial staining with EBD was positive in 9.82 % of the myocardial cross sectional areas examined, most of which was consistent with sarcolemmal rupture and oncosis with inflammatory cell infiltration. It is concluded that myocyte oncosis provides the major mechanism for the decreased number of myocyte nuclei and the early decrease of cardiac function between 1 and 2 mo of age in the CM hamster, with only a small contribution of myocyte apoptosis. Received: 28 May 2001, Returned for revision: 8 June 2001, Revision received: 15 June 2001, Accepted: 18 June 2001  相似文献   
89.
C Orkin  ST Sadiq  L Rice  F Jackson 《HIV medicine》2010,11(3):187-192

Objectives

Human leukocyte antigen (HLA)‐B*5701 is strongly associated with developing a hypersensitivity reaction to abacavir (ABC) in White and Hispanic subjects. Across the UK, limited data exist on HLA‐B*5701 prevalence in HIV‐1‐infected subjects. We determined HLA‐B*5701 prevalence in the general HIV‐1‐infected population and in specific ethnic groups, particularly Black Africans who, in general, exhibit greater genetic diversity. We also compared HLA‐B*5701 results obtained from local laboratories with those from a central provider.

Design and methods

Multi‐centre, observational study. All HIV‐1‐infected adult individuals receiving care at participating centres were eligible, irrespective of treatment status or prior exposure to ABC. Subjects provided samples for HLA‐B*5701 assessment by both local (blood) and central laboratories (buccal swabs). HLA‐B*5701 prevalence was adjusted to represent the ethnic group composition of the general UK population, and by main ethnic group.

Results

From eight UK centres, 1494 subjects [618 (41%) White, 770 (52%) Black] were recruited. Eighty‐nine per cent of Black subjects reported an immediate country of origin in Africa. Overall adjusted HLA‐B*5701 prevalence was 4.55% [95% confidence interval (CI) 3.49% to 5.60%]. Among White subjects, prevalence was 7.93% (CI 5.80% to 10.06%). Among Black subjects, only two (both Ugandan) were HLA‐B*5701 positive giving a rate of 0.26% (CI 0.07% to 0.94%).

Conclusions

HLA‐B*5701 prevalence was similar to previously reported rates in White HIV‐infected subjects but considerably lower than that reported in Black HIV‐1‐infected subjects, as a result of the large proportion of Black African subjects.  相似文献   
90.
Study Objective: to determine whether digoxin is effective in converting atrial fibrillation of recent onset to normal sinus rhythm. Design: randomized, double-blinded, placebo-controlled trial with a maximum 18-hour treatment period. Setting: emergency room and medical floors of a non-referral city hospital. Patients: consecutive sample of 36 patients with atrial fibrillation of 7 days' duration or less, not on digitalis glycoside or anti-arrhythmic agents, with ventricular rate between 85 to 175 beats/min, without evidence of heart failure, acute myocardial infarction, unstable angina, preexcitation syndrome, thyrotoxicosis, hypokalemia, renal impairment, or severe metabolic disturbances. Interventions: digoxin solution in capsules or identical placebo, given in doses of 0.6, 0.4, 0.2, and 0.2 mg, at 0, 4, 8, and 14 hours, respectively, or until conversion to sinus rhythm, whichever occurred first. Continuous electrocardiographic recording by Holter monitor. Measurements and Main Results: nine of eighteen patients receiving digoxin and 8 of 18 receiving placebo had a return to sinus rhythm within 18 hours of study entry (95% confidence interval for the difference in proportions, -11% to 22%). Mean time to conversion was 5.1 hours in the digoxin group and 3.3 in the placebo group (95% Cl, -3.6 to 7.0 hours). Conclusions: spontaneous reversion to sinus rhythm is common in patients with atrial fibrillation of recent onset. Digitalization was not shown to affect the likelihood of reversion to sinus rhythm, and thus cannot be recommended for this purpose in patients with atrial fibrillation.  相似文献   
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