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91.
92.
BACKGROUND: Intravenously administered perfluorocarbon (PFC) emulsions increase oxygen solubility in plasma. PFC might therefore temporarily replace red cells (RBCs) lost during intraoperative hemorrhage. In patients who have undergone hemodilution, the return of autologous blood may be delayed by the administration of PFC, and autologous RBCs may be saved for transfusion after surgical bleeding is stopped and PFC is cleared by the reticuloendothelial system. STUDY DESIGN AND METHODS: In 22 anesthetized, hemodiluted dogs (hemoglobin [Hb] 7 g/dL) breathing 100-percent O2, an intraoperative volume-compensated blood loss was simulated. The efficacy of three therapeutic regimens in maintaining tissue oxygenation was compared: 1) RBC group (n = 7): maintenance of a Hb > 7 g per dL by transfusion of autologous RBCs; 2) PFC group (n = 7): bolus application of a second-generation PFC emulsion (60% wt/vol perflubron) and further acute normovolemic hemodilution (ANH) to a Hb of 3 g per dL; and 3) control group (n = 7): further ANH alone to a Hb of 3 g per dL. Systemic and myocardial oxygenation status and tissue oxygenation were assessed. RESULTS: Autologous RBCs transfused to maintain a Hb of 7 g per dL preserved hemodynamics and tissue oxygenation during blood loss. In the PFC and control groups, heart rate and cardiac index increased significantly in response to further ANH. Tissue oxygenation was not different in the PFC and the RBC groups. Direct comparison of the PFC and control groups revealed better tissue oxygenation in the PFC group, as reflected by significantly higher mixed venous, coronary venous, and local tissue pO2 on liver and skeletal muscle. CONCLUSION: Bolus intravenous administration of 60- percent (wt/vol) perflubron emulsion and further hemodilution from a Hb of 7 g per dL to one of 3 g per dL were as effective as autologous RBC transfusion in maintaining tissue oxygenation during volume-compensated blood loss designed to mimic surgical bleeding.  相似文献   
93.

Background

Prevalence and risk factors for Chlamydia trachomatis infection among young men in Switzerland is still unknown. The objective of the present study was to assess prevalence and risk factors for C. trachomatis infection in young Swiss men.

Methods

517 young Swiss men were enrolled in this cross-sectional study during their compulsory military recruitment. Participants completed a questionnaire and gave urine samples which were screened for C. trachomatis DNA by PCR. Genotyping of positive samples was done by amplification and sequencing the ompA gene.

Results

The prevalence of chlamydial infection among young Swiss male was 1.2% (95% confidence interval [95%CI], 0.4–2.5%). C. trachomatis infection was only identified among the 306 men having multiple sexual partner. Although frequent, neither unprotected sex (absence of condom use), nor alcohol and drug abuse were associated with chlamydial infection. Men living in cities were more frequently infected (2.9%, 95%CI 0.8–7.4%) than men living in rural areas (0.5%, 95%CI 0.1–1.9%, p = 0.046). Moreover, naturalised Swiss citizens were more often positive (4.9%, 95%CI 1.3–12.5%) than native-born Swiss men (0.5%, 95%CI 0.1–1.7%, p = 0.003).

Conclusion

In comparison with other countries, the prevalence of chlamydial infection in men is extremely low in Switzerland, despite a significant prevalence of risky sexual behaviour. C. trachomatis infection was especially prevalent in men with multiple sexual partners. Further research is required (i) to define which subgroup of the general population should be routinely screened, and (ii) to test whether such a targeted screening strategy will be effective to reduce the prevalence of chlamydial infection among this population.  相似文献   
94.
Liver steatosis is common in human immunodeficiency virus (HIV)‐hepatitis C virus (HCV)‐co‐infected patients. Some recent studies have found that cannabis use is negatively associated with insulin resistance in the general population and in HIV‐HCV‐co‐infected patients. Given the causal link between insulin resistance and steatosis, we hypothesized that cannabis use has a positive impact on steatosis. Therefore, we aimed to study whether cannabis use in this population was associated with a reduced risk of steatosis, measured by ultrasound examination. ANRS CO13‐HEPAVIH is a French nationwide multicentre cohort of HIV‐HCV‐co‐infected patients. Medical and socio‐behavioural data from clinical follow‐up visits and annual self‐administered questionnaires were prospectively collected. A cross‐sectional analysis was conducted using data from the first visit where both ultrasound examination data for steatosis (positive or negative diagnosis) and data on cannabis use were available. A logistic regression model was used to evaluate the association between cannabis use and steatosis. Among study sample patients (n = 838), 40.1% had steatosis. Fourteen per cent reported daily cannabis use, 11.7% regular use and 74.7% no use or occasional use (“never or sometimes”). Daily cannabis use was independently associated with a reduced prevalence of steatosis (adjusted odds ratio [95% CI] = 0.64 [0.42;0.99]; P = .046), after adjusting for body mass index, hazardous alcohol consumption and current or lifetime use of lamivudine/zidovudine. Daily cannabis use may be a protective factor against steatosis in HIV‐HCV‐co‐infected patients. These findings confirm the need for a clinical evaluation of cannabis‐based pharmacotherapies in this population. Eudract.ema.europa.eu number, DGS050367.  相似文献   
95.
BACKGROUND: The occurrence of viral control after interruption of an antiretroviral treatment (ART) initiated during primary HIV-1 infection (PHI) is rare and the frequency and predictive factors of such a control are unknown. METHODS: Within the French ANRS PRIMO Cohort, 164 patients interrupted ART initiated during PHI. We compared patients whose viral load (VL) remained undetectable (<50 copies/ml) or low (50-500 copies/ml) 1 year after ART interruption to those who evidenced a rapid viral rebound. RESULTS: After ART interruption, VL remained undetectable for a median time of 4.5 years in 14 patients ('post-ART controllers') and low in another 14 patients for a median time of 1.5 years. Post-ART controllers also maintained higher CD4(+) T-cell counts compared to other patients. Female gender, a high CD4(+) T-cell count and low VL during PHI, and a high CD4(+) T-cell count and low HIV DNA levels at interruption, were associated with post-ART HIV control. Treatment characteristics did not differ between controllers and non-controllers. Post-ART controllers had lower specific CD8(+) T-cell frequencies and CD8(+) T-cell activation on ART and after ART interruption than non-controllers. CONCLUSIONS: Few patients maintain very low VL after interruption of treatment initiated during PHI. Early patient characteristics were the main factors of viral control, although early initiation of ART and the effect of ART on reservoir might contribute to control.  相似文献   
96.
97.
98.
Damage occurs early in systemic vasculitis and is an index of outcome   总被引:2,自引:0,他引:2  
Because death after acute systemic vasculitis is now uncommon, alternative measures of outcome are required. A significant component of patient morbidity is disease-related damage, which can be quantified by the Vasculitis Damage Index (64 items in 11 organ-based systems). We investigated serially the time-course of damage in 120 patients with systemic vasculitis, to determine the earliest indicators of outcome. High damage scores at 2 years after presentation were characteristic of fatal disease (OR 8.1-12.4). Significant damage occurred within 6 months of presentation, and was a feature of fatal disease. More damage occurred after presentation than after relapse. Lung and multi-system damage were early indicators of poor outcome in severe non-fatal disease. Damage occurs early in systemic vasculitis, and is an indicator of poor outcome. This novel observation, together with evidence of persistent subclinical disease activity and the high frequency of relapse, suggests a need for new treatment strategies. Analogy with the management of acute leukaemia suggests a strategy of early diagnosis and intensive induction of remission, with early escalation of treatment for resistant disease.   相似文献   
99.

Background  

Bicycling has the potential to improve fitness, diminish obesity, and reduce noise, air pollution, and greenhouse gases associated with travel. However, bicyclists incur a higher risk of injuries requiring hospitalization than motor vehicle occupants. Therefore, understanding ways of making bicycling safer and increasing rates of bicycling are important to improving population health. There is a growing body of research examining transportation infrastructure and the risk of injury to bicyclists.  相似文献   
100.
A 5-month-old white boy had a pinhead red spot on his left malleolar region since birth. His mother noted progressive growth and, when he was first examined, the lesion measured 30x25x20 mm in size, had a pyramidal shape, covered by erythematous and smooth skin, with teleangiectasia. The tumor was soft on paipation and movable over the deeper structures (Fig. 1a). X-ray examination revealed no bone abnormalities at that time.
Just before the programmed incisional biopsy, the patient had a febrile episode due to upper respiratory tract viral infection during which the tumor became ulcerated, bleeding and painful (Fig. 1b). As the bleeding was constant the lesion was surgically excised, at which time the whole gelatinous mass was easily detached from the aponeurotic structures (Fig. 1c). The tumor measured 36x31 x30 mm and had a whitish, smooth cut surface crossed by small blood vessels.
Histopathologic examination revealed a tumor mass extending from the mid dermis to the subcutaneous fat and composed of tightly packed fusiform cells in close opposition with lined vascular channels (Fig. 2a). There were atypical areas and mitotic figures were frequently seen. A reticulin preparation showed a dense network surrounding vessels and pericytes. The vessels branched in a staghorn configuration (Fig. 2b). The immunoperoxidase technique with monoclonal antibody anti-Factor VIII was positive in the endothelial cells surrounded by tumor cells (Fig. 2c).
Seven months after surgery the patient returned with a painful subcutaneous mass on the upper third of his left leg that was adherent to the tibial bone. X-ray examination disclosed osteolytic lesions at the tibial base and destruction of the peroneal head (Fig. 3).
The patient was submitted to radiotherapy, amputation of the left lower limb in the middle portion of the thigh and chemotherapy. He is clinically well 3 years after treatment.  相似文献   
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