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81.
Hepatitis C virus (HCV) causes acute and chronic hepatitis which can lead to HCC (Hepatocelluar carcinoma) via oxidative stress, steatosis, insulin resistance, fibrosis and liver cirrhosis. Apoptosis is essential for the control and eradication of viral infections. In acute HCV infection, enhanced hepatocyte apoptosis is significant for elimination of viral pathogen. In case of chronic HCV, down regulation of apoptosis and enhanced cell proliferation not only causes HCV infection persistency in the majority of patients. However, the impact of apoptosis in chronic HCV infection is not well understood. It may be harmful by triggering liver fibrosis, or essential in interferon (IFN) induced HCV elimination. Regulation of apoptosis in hepatocytes by HCV Core is so important in progression of HCC. This review focuses on the dual character of HCV Core on regulation of apoptosis and progression of HCC.  相似文献   
82.

Background

Ultrasound is an ideal imaging modality for low-resource settings given its portability, ease of use, and wide range of applications. Commercially available ultrasound gels may be unavailable or cost prohibitive in low-resource settings.

Objective

Our aim was to investigate the quality of images obtained with an alternative ultrasound gel made from cornstarch and water in comparison with commercially available gel.

Methods

The cornstarch gel was made by heating water and cornstarch. The gel was used to obtain standard ultrasound images of the gallbladder, kidneys, bladder, heart, and neck vessels by the study investigators. Commercial gel was used as the control. Twenty-four ultrasound clips were shown to four blinded radiologists and two ultrasound-fellowship−trained emergency department physicians. They rated the images on adequacy (yes/no) and graded the images detail, resolution, and quality using a continuous 0−10 scale.

Results

A total of 144 video clips were shown to reviewers and 129 data-collection sheets were returned. There was no statistical difference in the proportion of images deemed to be of adequate quality: cornstarch-based gel = 0.97 (95% confidence interval [CI] 0.92−1.00) vs. commercially available gel = 0.85 (95% CI 0.75−0.94) (p = 0.053). The cornstarch gel was superior to commercial gel on all three image parameters: detail (p = 0.002), resolution (p = 0.018), and quality (p = 0.013).

Conclusions

In this study, a gel made from cornstarch and water was an acceptable coupling medium and provided equally adequate images as compared with commercial ultrasound gel. This inexpensive gel made from ubiquitous materials can be an acceptable alternative to commercial gel in low-resource settings.  相似文献   
83.
84.

Purpose

Clinical and epidemiologic investigations suggest a strong association between obesity and obstructive sleep apnea (OSA). The purpose of this study is to evaluate the currently available literature reporting on the effectiveness of dietary weight loss in treating OSA among obese patients.

Methods

Relevant studies were identified by computerized searches of PubMed, EMBASE, CINAHL, Web of Science, and The Cochrane Central Register of Controlled Trials through September 2011 as well as the reference lists of all obtained articles. Information on study design, patient characteristics, pre- and post-dietary weight loss measures of OSA and body mass index (BMI), and study quality was obtained. Data were extracted by two independent analysts. Weighted averages using a random-effects model are reported with 95 % confidence intervals.

Results

Nine articles representing 577 patients were selected. Dietary weight loss program resulted in a pooled mean BMI reduction of 4.8 kg/m2 (95 % confidence interval [CI] 3.8-5.9). The random-effects pooled apnea hypopnea (AHI) indices at pre- and post-dietary intervention were 52.5 (range 10.0–91.0) and 28.3 events/h (range 5.4–64.5), respectively (p?<?0.001). Compared to control, the weighted mean difference of AHI was decreased by ?14.3 events/h (95 % CI ?23.5 to ?5.1; p?=?0.002) in favor of the dietary weight loss programs.

Conclusions

Dietary weight loss programs are effective in reducing the severity of OSA but not adequate in relieving all respiratory events. Weight reduction programs should be considered as adjunct rather than curative therapy.  相似文献   
85.
We report a new transvenous endovascular route for treatment of dural arteriovenous fistulas of the cavernous sinus. The cavernous sinus was approached from the contralateral pterygoid plexus and embolization of a dural fistula was performed successfully with Guglielmi detachable coils. Received: 16 June 1997 Accepted: 6 August 1997  相似文献   
86.
Hydroxyl radical, a prominent entity of reactive oxygen species, is known to modify cellular DNA and has been implicated in several human diseases. In the present studies, the radical was generated by exposure of hydrogen peroxide to 254 nm light in the presence of native calf thymus DNA. Single strand breaks, decrease in Tm and modification of adenine and thymine were some of the modifications observed in nDNA. Antibodies induced in experimental animals against the modified DNA were immunogen specific. These antibodies also recognize native B-conformation. It was observed that naturally occurring anti-native DNA autoantibodies from SLE sera recognize modified DNA in direct binding and competition ELISA. Gel retardation assay reiterated the formation of immune complexes between induced antibodies and DNA fragments of around 300 bp (B-conformation). The possible significance of these findings in the etiology of SLE has been discussed.  相似文献   
87.
88.
Progressive familial intrahepatic cholestasis (PFIC) is an important cause of cholestatic liver disease and biliary cirrhosis in pediatric population. Three cases of PFIC are described that were diagnosed on the basis of family history, pruritus, cirrhosis and / or paucity of interlobular bile ducts on liver biopsy and presence of extrahepatic biliary tree on imaging. These patients were initially labeled as suffering from extra-hepatic biliary atresia and neonatal hepatitis. PFIC-1 and 2 could not be differentiated on histological grounds, since these patients presented late and process of fibrosis was advanced.  相似文献   
89.
OBJECT: The Matrix detachable coil is a new bioactive, bioabsorbable coil used in the endovascular embolization of intracranial aneurysms. It has a platinum core covered with a bioactive, bioabsorbable polymer (polyglycolic acid/lactide). The authors report on their initial midterm clinical experience with the first-generation Matrix detachable coil. METHODS: One hundred twelve patients harboring 118 aneurysms were treated using Matrix coils. Forty-nine aneurysms (41.5%) were associated with acute subarachnoid hemorrhage (SAH). Twenty-four lesions (49%) were harbored by patients with Hunt and Hess Grade I, 11 (23.4%) by patients with Grade II, eight (16.3%) by those with Grade III, and six (12.2%) by those with Grade IV. Four aneurysms (3.4%) were harbored by patients who had presented with nonacute SAH. Sixty-five aneurysms (55%) were unruptured. Fifty-seven lesions (48.3%) were small with a small neck, 29 (24.6%) were small with a wide neck, 30 (25.4%) were large, and two (1.7%) were giant. All patients were followed up to obtain angiography and clinical outcome data. Technical complications occurred in six patients: two thromboembolic complications and four aneurysm perforations. Of these six patients, the status of two deteriorated because of aneurysm perforation and another two because of thrombus formation (morbidity 3.6%). There were five deaths--one due to rerupture after embolization. Angiography follow-up studies of 87 aneurysms were obtained. Seventy aneurysms demonstrated progressive occlusion or a stable neck (80.5%), and 17 had some degree of recanalization (19.5%). The aneurysms originally diagnosed as a neck remnant showed a 15% rate of recanalization. CONCLUSIONS: Matrix coils can be delivered into aneurysms with technical complications similar to those encountered using GDCs. Midterm anatomical outcomes to date have shown moderate improvement in the recanalization rate when compared with those realized using the GDC system. Because of the increased friction associated with the first-generation Matrix coil, the packing density in most aneurysms was less than that achieved with GDCs. Prolonged angiography follow-up evaluations are needed to document long-term efficacy.  相似文献   
90.
A major limitation of adoptive immunotherapy is the availability of T cells specific for both terminally differentiated tumor cells and their clonogenic precursors. We show here that marrow-infiltrating lymphocytes (MILs) recognize myeloma cells after activation with anti-CD3/CD28 beads with higher frequency than activated peripheral blood lymphocytes from the same patients. Furthermore, activated MILs target both the terminally differentiated CD138+ plasma cells and the myeloma precursor as shown by profound inhibition in a tumor clonogenic assay. The presence of antigen in the marrow microenvironment seems to be important for the maintenance of tumor specificity. Taken together, these results highlight the intrinsic tumor specificity of MILs and describe a novel approach for the generation of tumor-specific T-cell populations suitable for adoptive immunotherapy of multiple myeloma.  相似文献   
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