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71.
Many studies dealing with differences between students' and doctors' memory for clinical cases have yielded puzzling results. In this paper it is claimed that these are due to the use of inadequate techniques for isolating chunks inherent in the stimuli and the data. The purpose of this paper is to investigate whether the techniques of propositional analysis yield a clearer picture. Using this technique, the analysis of two sets of data is presented. The results show a clear difference between doctors and students when relevant clinical information is isolated from irrelevant information. This supports the notion that the process involved in the memory for clinical cases is far more complex and involves the ability to make inferences from a highly developed knowledge base.  相似文献   
72.
Enhancement of Natural Killer Cell Activity by Nocardia opaca Fractions   总被引:1,自引:0,他引:1  
Three molecules derived from Nocardia opaca bacteria, NDCM, NWSMP, and PG, have been shown to express immunomodulating properties. The present study was aimed at assessing the effects of these derivatives on natural killer (NK) activity. Two experimental protocols were adopted, consisting of incubating whole or Percoll fractionated NK cells in vitro with those substances, and the other in which the derivatives were administered in vivo to mice and the activity assessed later. Incubation of spleen cells in vitro with NWSMP or its precursor NDCM promoted NK activity. This effect could be observed after only 2 h of incubation and continued until day 2. Percoll fractions 1-3, which contain most of the NK activity, were enhanced to a similar extent. Band 4, which is usually devoid of such activity, remained unresponsive even after contact with the N. opaca derivatives. PG was practically ineffective upon all the subsets. The results of experiments in vivo correlated with those obtained in vitro in that NWSMP and NDCM, but not PG, promoted NK activity. Bands 1-3 were similarly enhanced, the effect was observed after short treatment times, and could be partially cancelled by the concomitant administration of anti-interferon antibodies (anti-IFN Ab). All these findings suggest that the promoting effects of N. opaca derivatives are mediated through alpha/beta IFN. In contrast to the results observed on spleen NK cells, NK cells from the peritoneum displayed susceptibility mainly to PG, and much less to NWSMP or NDCM. The administration of PG to mice in vivo had a particularly marked promoting effect upon the cytotoxic activity of peritoneal cells. One logical explanation for the difference observed between PG and NWSMP or NDCM may be related to the specific IFN inducing properties of these compounds as well as to the different responsiveness of the NK cells present in the spleen and peritoneal cavity.  相似文献   
73.
In this study we examined the staining reactivity of commercially available antisera to factor VIII related antigen (F VIII RAg) and Ulex europaeus agglutinin I (UEA-I) on sections from 230 formalin fixed paraffin embedded tumours. These included 196 sarcomas, 20 carcinomas and 14 angiomas. All angiomas showed positive staining for F VIII RAg; all carcinomas showed negative staining; the vasoformative areas of all angiosarcomas stained positively but only four of six angiosarcomas showed positive staining of their solid areas; of seven Kaposi's sarcomas, all showed positive staining of vessels and six showed positive staining of the spindle cell component. In the remaining 181 non-vascular sarcomas there was a false positive result in four tumours (2.2%), three of which had a history of irradiation. Pre-radiotherapy biopsies of these three tumours stained negatively with anti-F VIII RAg. UEA-I was demonstrated in all the angiomas studied, in all angiosarcomas (including the solid components) and in well-formed vessels of all Kaposi's sarcomas, but only in the spindle cell component of 3/6. However, there was an unacceptably high rate of false positive staining amongst the carcinomas and non-vascular sarcomas. In conclusion, F VIII RAg is a specific but not a sensitive marker of angiosarcomas; UEA-I is a sensitive but not a specific marker of angiosarcomas.  相似文献   
74.
75.
Summary We describe a patient with essential thrombocythaemia who developed multiple myeloma 7 years after an initial diagnosis of essential thrombocythaemia. A 50-year-old white female presented in 1987 with a 2 year history of low backache, painful swollen ankles and burning feet. Her laboratory investigations suggested a diagnosis of essential thrombocythaemia. Initially she was treated with busulphan without much benefit for 6 months. Subsequently she was treated with hydroxyurea with significant relief of her symptoms and reduction in her platelet count. Seven years after her initial presentation she developed bone pains and anaemia with laboratory investigations confirming a diagnosis of multiple myeloma.  相似文献   
76.
PVAI and Stroke . Introduction: Cerebral thromboembolic event (CTE) is a possible complication of pulmonary vein antrum isolation (PVAI). The objective of this study was to report long‐term functional and neurocognitive recovery in patients who had a CTE during or within 48 hours of catheter ablation. Methods and Results: We screened 3,060 patients who underwent PVAI between January 2000 and June 2007. Out the 3,060 patients, 26 patients (0.8%) (61 ± 8 years, 88% males) had a CTE during or within 48 hours of the procedure. We followed these 26 patients (study group) over time and assessed their functional and neurocognitive recovery status. No preferential vascular territory for the site of obstruction was found; right anterior circulation‐5 patients (26%), left anterior circulation‐5 patients (26%), posterior circulation‐3 patients (16%), and 2 or more territories‐6 patients (32%), (P‐value = 0.8). The average international normalized ratio at the time of CTE was 1.33 ± 0.4. Two patients died during the study period. At the end of 38.4 ± 24 months follow‐up, most surviving patients had complete neurocognitive and functional recovery irrespective of the severity of periprocedural stroke. Conclusions: Periprocedural stroke in the setting of catheter ablation for atrial fibrillation is relatively rare. When it occurs, complete functional and neurocognitive recovery over time is the likely outcome for most patients. (J Cardiovasc Electrophysiol, Vol. 21, pp. 412–417, April 2010)  相似文献   
77.
Summary.  Chronic hepatitis C (CHC), a curable infection, remains endemic worldwide. More than 90% of individuals with haemophilia have been infected with hepatitis C virus (HCV) mostly caused by transfusion with non-virucidally treated clotting factor concentrates. Relevant to haemophilics, the risk of cirrhosis with CHC infection is greatest in males, those who have been infected for a long time, consume alcohol regularly, and/or are co-infected with HIV. The cure rate, using the current standard therapy for CHC with pegylated-interferon-α given weekly and ribavirin daily, ranges from 43% to 65% in those infected with genotype 1 and 50–90% with genotype 2 and 3 infections. Eradication of hepatitis C in those co-infected with HIV is less in part because full dose therapy is poorly tolerated. Achieving a sustained virological response (SVR) prevents progression to cirrhosis and in those with established cirrhosis prevents liver failure, and reduces the risk if hepatocellular carcinoma, and the need for liver transplant. Novel treatment options now in development are predominantly focused on inhibitors of HCV-specific enzymes. The treatment paradigm for haemophilics infected with hepatitis C is that all should be assessed for treatment once a diagnosis of chronic hepatitis C is made in order to achieve the highest chance of an SVR, i.e. cure.  相似文献   
78.
79.
Abstract: A case of onychomadesis in one of twins with onset in the neonatal period is reported. We hypothesize that the nail deformities were induced by the stress of a breech presentation during preterm labor and that candidiasis limited to the bands of onychomadesis exaggerated the appearance of the nail deformity.  相似文献   
80.

Background

Hemodialysis (HD) access failure is a common cause of increased morbidity and healthcare cost in patients with end stage renal disease (ESRD). Percutaneous balloon angioplasty has been used to treat hemodialysis access stenosis but is complicated by a high rate of restenosis. Percutaneous cutting balloon (PCB) angioplasty is an alternative approach that has shown to reduce restenosis.

Objectives

The aim of the study is to assess the safety and efficacy of PCB angioplasty in comparison with conventional and high‐pressure balloon angioplasty in the treatment of hemodialysis access site stenosis.

Methods

We searched PubMed, EMBASE and the Cochrane Central register of controlled trials (CENTRAL) databases through August 2014 and selected studies using the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) checklist. We included all randomized clinical trials with a head‐to‐head comparison between PCB and conventional or high‐pressure balloon angioplasty

Results

Three studies with 1034 participants (age 60.7 (±12.9) years and 50.1% males) with 525 in PCB and 509 in control arm were included in the analysis. The immediate procedural success rate was not significantly different in the PCB angioplasty and control arm respectively, (87.2% vs. 83.7% RD ?0.02; 95%CI ?0.06 to 0.01; P = 0.38). The six‐month target lesion patency was significantly higher in the PCB angioplasty arm (67.2% vs. 55.6% RD 0.12; 95%CI 0.05–0.19; P < 0.05) with number needed to treat (NNT) of 9. The device related complications were not statistically significant between groups (RD 0.03; 95%CI ?0.02 to 0.07; P = 0.26).

Conclusions

PCB angioplasty is effective in treatment of hemodialysis access stenosis, with significantly higher six‐month patency compared to balloon angioplasty. (J Interven Cardiol 2015;28:288–295)
  相似文献   
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