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101.
102.
Keratoacanthomas (KAs) resemble squamous cell carcinomas (SCCs) except that, unlike SCCs, after a period of rapid growth over a few months they involute completely. The basis of their regressing natural history is not known. We have examined keratoacanthomas and another benign cutaneous tumour, the basal cell papilloma (BCP), for loss of heterozygosity (LOH) at a number of loci that are frequently lost in SCCs and other skin tumours. The frequency of LOH for both KAs and BCPs was low, with only isolated losses identified at 9p, 9q and 10q in KAs [fractional allelic loss (FAL) was 1.3%], and at 9p and 17p in BCPs (FAL was 0.4%). This contrasts with previous work showing a FAL of 32% in SCC and 46% in actinic keratoses. The results show a clear difference between KA and SCC and do not support the hypothesis that KAs are SCCs that regress as a result of external (host) influences but rather suggest that KAs and SCCs are different de novo. LOH around the locus implicated in the multiple self-healing epitheliomata of Ferguson-Smith (9q22-q31) was shown in only 1 of 11 KAs.  相似文献   
103.
BACKGROUND: New techniques for laparoscopic cholecystectomy (LC) that reduce the number of trocars or use very thin instruments have been devised with the goal of further minimizing surgical invasiveness. METHODS: We performed two-trocar LC using an original new technique in 70 consecutive patients. A 10-mm trocar and a 5-mm trocar were inserted in the subumbilical and epigastrium positions, respectively. A 2-mm grasper forceps was inserted directly without a trocar below the costal margin. The fundus of the gallbladder was ligated and lifted up with a folded 0 silk string and a 16-gauge vessel cannula. RESULTS: The mean operative time was 73.2 +/- 23.5 min. A third trocar was added in two cases. None of the patients required conversion of the procedure to an open cholecystectomy, and there were no intraoperative complications. CONCLUSION: Based on our experience, we think that this technique is as safe and effective as the classic four-trocar technique; moreover, it has a cost benefit.  相似文献   
104.
105.
Cholecystokinin (CCK) is an important gastrointestinal hormone as well as a neurotransmitter. Two types of CCK receptors, types A and B, have been identified. The CCK-A receptor is involved in satiety, food intake and behavior, whereas the B receptor is involved in anxiety. We recently produced CCK-A, -B and AB receptor knockout mice to study the role of these receptors in energy metabolism. Daily energy intake and expenditure were significantly greater in CCK-BR(-/-) and CCK-AR(-/-)BR(-/-) mice than CCK-AR(-/-) and wild-type [CCK-AR(+/+)BR(+/+)] mice. Relative liver and kidney weights (g/kg body) were significantly greater in CCK-AR(-/-)BR(-/-) mice than in wild-type mice. Energy metabolism and energy turnover were increased in mice with a disruption of the CCK-BR gene, although the underlying mechanism is unknown.  相似文献   
106.
Association with Epstein-Barr virus (EBV) infection has been noted in various types of cutaneous lymphoproliferative disorders. We report a 57-year-old Japanese woman with T-cell lymphoma mimicking dermatomyositis that was associated with chronic active EBV infection. She presented with low-grade fever, bilateral erythematous swellings on the eyelids, and necrotic papules on the face. Serum creatine kinase levels were elevated and a diffuse reticular shadow was detected in both lung fields. The infiltrate of atypical lymphocytes found in skin and muscle, which contained EBV-encoded small nuclear RNA-1 and EBV, was also detected in the CD4+ peripheral blood cells. Treatment with prednisolone resolved her lesions with no relapse for 3 years, after which there was a recurrence in her left lung. Combination chemotherapy was not effective against the lung lesion and she died with multiple organ failure 2 months after the recurrence.  相似文献   
107.
Clinical significance of p21 expression in non-small-cell lung cancer.   总被引:6,自引:0,他引:6  
PURPOSE: The clinical significance of p21 expression remains unclear, whereas many experimental studies have demonstrated that p21, the product of the WAF1/CIP1/SDI1 gene, plays an important role in regulation of the cell cycle as an inhibitor of cyclin-dependent kinases. The purpose of this study was to clarify the clinical significance in resected non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 233 consecutive patients with completely resected pathologic stage I to IIIA NSCLC were retrospectively reviewed. Expression of p21 and the status of p53 were examined immunohistochemically. Proliferative activity was also evaluated immunohistochemically. The incidence of apoptotic cell death was evaluated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling staining. RESULTS: Expression of p21 was positive in 120 patients (51.5%). The 5-year survival rate of p21-positive patients was 73.8%, significantly higher than that of p21-negative patients (60.7%; P =.006). Aberrant expression of p53 was positive in 98 patients (42.1%). When combined with p53 status, the prognostic value of p21 status was enhanced: the 5-year survival rate of p21-positive and p53-negative patients was 80.7%, markedly higher than that of p21-negative and p53-positive patients (50.0% for both; P =.001). Multivariate analysis confirmed that positive expression of p21 was a significant factor for predicting a favorable prognosis. There was no significant correlation between p21 expression and p53 status, proliferative activity, or incidence of apoptosis. CONCLUSION: p21 expression was shown to be an independent prognostic factor in NSCLC.  相似文献   
108.
OBJECTIVES: To clarify the virological state of human immunodeficiency virus (HIV)-1-infected patients, we compared the plasma HIV-1 RNA copy number (plasma viral load (VL)), viral DNA and mRNA burdens in peripheral blood mononuclear cells (PBMCs), and the other clinical predictors. METHODS: One hundred and thirty-one samples of PBMCs and plasma from 26 patients infected with HIV-1 were obtained during 20 consecutive months for the measurement of VL, viral DNA and mRNA burdens, and CD4 positive (CD4+) cells count. The quantitative polymerase chain reaction (PCR) method with detection by solid phase DNA was utilized for the assay of VL, viral DNA and mRNA burdens. RESULTS: Eighty-six VL, 101 viral mRNA and 129 viral DNA out of 131 samples were detected. There was a significant positive correlation between VL and the viral mRNA burden (r = 0.600, P < or = 0.001), and between VL and the viral DNA burden (r = 0.368, P < or = 0.001). Focused on individuals, the viral mRNA burdens varied in a manner relatively dependent on VL when both values were detectable. However, viral DNA burdens varied relatively independently of VL and the viral mRNA burdens. In six patients the viral mRNA burden was detectable and changed even if the VL was undetectable throughout the observation period. CONCLUSIONS: Both viral DNA and viral mRNA burdens still showed detectable changes even when the VLs became undetectable in most patients. The measurement of viral mRNA or DNA burdens may be clinically available to identify viral replication when VL is undetectable.  相似文献   
109.
Organ transplant recipients receiving immunosuppression show a dramatically increased risk of non-melanoma skin cancer. The cause of this increase is not known. We report that the rate of loss of heterozygosity (at all the loci we examined) was significantly lower in tumours from immunosuppressed individuals than in tumours from immunocompetent subjects [20 out of 148 (14%) vs 157 out of 428 (37%); P< 0.0001]. These results suggest that tumours in immunosuppressed individuals have a different molecular pathogenesis.  相似文献   
110.
Objectives: To evaluate Japanese occupational health services (OHSs) for small-scale enterprises (SSEs). Methods: The current Japanese OHSs for SSEs were compared with 15 recommendations of the Joint WHO/ILO Task Group. The status of OHSs was analyzed using the published papers collected by means of a computerized literature search. Thirty-five papers were used in the analysis, which was first conducted by the four authors separately, followed by discussion among the authors. Evaluation was conducted by classifying the status of Japanese OHSs for SSEs into three classes (A: good, B: average, C: poor) based on comparison with each recommendation. Results: Six issues were evaluated as “A”: establishment of a national policy for the provision of OHSs for SSEs, occupational health and safety inspection for SSEs, legislation to ensure services for SSEs and provision of financial incentives, adoption of occupational health programs using multiple channels, training in occupational health issues, and establishment of national data collection and registration systems. Nine issues were evaluated as “B”: provision of OHSs for all SSEs as a part of the “national Health for ALL” strategy, intervention combining economic development and OHSs, extension of OHSs to vulnerable groups, coverage of migrant and seasonal workers by OHSs, the establishment of a national collaborative and coordinative body on OHSs, control of transfer of hazardous technology, encouragement of applied research, employers' commitment and worker participation, and integration of OHSs with primary health care. None of them was evaluated as “C”. Conclusions: Japanese OHSs for SSEs were fairly well established in terms of compliance with the recommendations of the Joint WHO/ILO Task Group, although evaluation may be somewhat subjective and rather qualitative. Received: 08 September 1999 / Accepted: 31 January 2000  相似文献   
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