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51.
Angiomyolipoma (AML) is a uncommon benign neoplasm of the liver with cyto‐ and histologic features similar to the more commonly encountered renal AML. Tumors composed predominantly of epithelioid cells have been referred to as epithelioid AML. Because most liver lesions are first evaluated by fine‐needle aspiration biopsy (FNAB), it is important to distinguish this variant of AML from more common hepatic neoplasms such as hepatocellular carcinoma (HCC) or metastatic tumors. Rare reports of epithelioid AML of the liver diagnosed by FNAB are in the literature. Here, we describe the cytologic findings of a unique case of epithelioid AML with numerous giant cells. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
52.
Hereditary spastic paraplegias (HSP) constitute a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by slowly progressive spasticity of the lower extremities. We performed the first clinical, epidemiological and genetic study of HSP in Southern Tunisia. We investigated 88 patients belonging to 38 unrelated Tunisian HSP families. We could establish the minimal prevalence of HSP in the district of Sfax at 5.75/100,000. Thirty‐one percent of the families had a pure HSP, whereas 69% had a complicated form. The mode of inheritance was almost exclusively compatible with an autosomal recessive trait (97%, 37/38). Taking into account previously published results and new data generated in this work, genetic studies revealed significant or putative linkage to known HSP loci in 13 families (34.2%) to either SPG11 (7/38, 18.4%), SPG15 (4/38, 10.5%) or to SPG4 and SPG5 in one family each. The linkage results could be validated through the identification of two recurrent truncating mutations (R2034X and M245VfsX246) in the SPG11 gene, three different mutations (Q493X, F683LfsX685 and the novel S2004T/r.?) in the SPG15 gene, the recurrent R499C mutation in the SPG4 gene as well as the new R112X mutation in the SPG5 gene. SPG11 and SPG15 are the major responsible HSP genes in Tunisia.  相似文献   
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Objective

The aim of this study was to evaluate the frequency and main risk factors for corneal graft rejection.

Patients and Methods

This retrospective study included 285 eyes in 256 patients who underwent a penetrating keratoplasty (KPT) from January 1995 to December 2004. The minimum follow-up was 12 months to evaluate graft evolution. Except for complications, the follow-up was weekly, then monthly for 6 months, and ultimately quarterly during the first year. Thereafter the follow-up was performed semi-annually. Patients were informed about the functional signs for which they have to urgently consult.

Results

Immunologic rejection of the corneal graft occurred in 128 KPT in 112 patients (rejection frequency = 41%). The identified main risk factors were new vascularization of the recipient cornea over 2 or more quadrants, corneal opacity due to an infectious origin, posttraumatic corneal opacity or congenital glaucoma, graft diameter >8 mm, and therapeutic KPT.

Conclusions

Rejection of the corneal graft is the primary cause of KPT failure. One out of 2 graft failures was due to rejection. Two criteria are unanimously recognized as risk factors for rejection: neovascularization of recipient cornea and antecedents of corneal rejection. The rejection must be treated early to not endanger graft success, which imposes a close follow-up for grafted patients.  相似文献   
56.
The central role of Src in the development of several malignancies, including breast cancer, and the accumulating evidence of its interaction with receptor tyrosine kinases, integrins, and steroid receptors have identified it as an attractive therapeutic target. In the current study, we have evaluated the effect of a Src/Abl kinase inhibitor, SKI-606, on breast cancer growth, migration, invasion, and metastasis. Treatment of human breast cancer cells MDA-MB-231 with SKI-606 caused a marked inhibition of cell proliferation, invasion, and migration by inhibiting mitogen-activated protein kinase and Akt phosphorylation. For in vivo studies, MDA-MB-231 cells transfected with the plasmid encoding green fluorescent protein (GFP; MDA-MB-231-GFP) were inoculated into the mammary fat pads of female BALB/c nu/nu mice. Once tumor volume reached 30 to 50 mm(3), animals were randomized and treated with vehicle alone or 150 mg/kg SKI-606 by daily oral gavage. Experimental animals receiving SKI-606 developed tumors of significantly smaller volume (45-54%) compared with control animals receiving vehicle alone. Analysis of lungs, liver, and spleen of these animals showed a significant decrease in GFP-positive tumor metastasis in animals receiving SKI-606 at a dose that was well tolerated. Western blot analysis and immunohistochemical analysis of primary tumors showed that these effects were due to the ability of SKI-606 to block tumor cell proliferation, angiogenesis, growth factor expression, and inhibition of Src-mediated signaling pathways in vivo. Together, the results from these studies provide compelling evidence for the role of Src inhibitors as therapeutic agents for blocking breast cancer growth and metastasis.  相似文献   
57.
目的 观察MMTV Wnt 1转基因小鼠的乳腺癌发病情况及病理学变化规律。方法 观察MMTV Wnt 1转基因小鼠肿瘤发生情况 ,并采用原位移植将瘤组织置于裸鼠皮下 ,通过组织病理学切片来观察MMTV Wnt 1阳性转基因小鼠和移植鼠的病理学变化。结果 MMTV Wnt 1转基因小鼠最早从 7周龄开始出现乳腺瘤 ,发瘤鼠剖检可见脾、肝有不同程度的肿大 ,其他器官无明显病变 ;病理组织学检查发现发瘤鼠各脏器有不同程度的病变 ,但未出现肿瘤转移。将瘤组织移植裸鼠后 ,肿瘤可在裸鼠皮下生长 ,移植肿瘤病理学形态与原发瘤一致 ,未出现转移。结论 实验结果验证MMTV Wnt 1转基因小鼠可稳定自发乳腺肿瘤 ,可作为研究乳腺癌的良好的动物模型  相似文献   
58.
Human leukocyte antigens (HLAs) of class I and class II are reported to influence the outcome of hepatitis C virus (HCV) infection. The aim of this study was to assess the role of HLA class I and class II in influencing spontaneous viral clearance or persistence in HCV-infected patients. HLA class I (A and B) typing was performed by lymphocytotoxicity test and HLA class II (DRB1) was determined by low-resolution PCR-SSP (polymerase chain reaction amplification with sequence-specific primers) for 99 subjects (48 men and 51 women). Of these, 75 had chronic infection and 24 had viral clearance. No significant differences were observed between individuals with spontaneous viral clearance or chronic HCV infection for age, sex, source of infection, and risk factors. HLAB-w35 and HLA-DRB1*08 occurred more frequently in those with viral clearance (21.7 and 16.6%, respectively) compared with those with chronic infection (5.5 and 2.6%; p < 0.04 and p < 0.01, respectively). DRB1*15 occurred more often in those with chronic infection (29.3%) compared with those with viral clearance (16.66%), but the difference did not reach statistical significance. These results support the hypothesis that specific HLA class I and class II alleles might influence the clearance or persistence of HCV infection. Both Bw35 and DRB1*08 are associated with clearance of circulating HCV whereas DRB1*15 appears to predispose to progression of liver disease in Tunisian patients. Taken together, our results and those previously reported suggest that HLA associations with the outcome of hepatitis C viremia vary in relation to the ethnicity of the population studied. Further prospective studies of larger cohorts of HCV-infected subjects are needed to evaluate, in different populations, the role of specific HLA class I and class II alleles in the outcome of HCV infection.  相似文献   
59.
OBJECTIVE: Our aim is to report the clinical aspects, the etiologies, the treatment and the evolution of the psoas abscess in the adult. METHODS: Our retrospective study concerns 38 cases of psoas abscesses collected in the Department of Infectious Diseases of Sfax (Tunisia), over a period of 16 years (January 1990 - December 2005). RESULTS: The average age is 44 years (extremes: 16-76 years). The sex-ratio is 1.4. Six patients were diabetics and one had a chronic renal injury at the stage of hemodialysis. The clinical manifestations were: a fever (76.4%), an abdomino-pelvic ache (84.2%) and a psoitis (34.2%). All patients had a biologic inflammatory syndrome with a hyperleucocytosis in 28 cases. The abscess was one-sided in 29 cases and bilateral in 9 cases. After microbiological study and/or histological study, pathogens were identified in 31 patients, they were Staphylococcus aureus (10 cases), Staphylococcus lugdunensis (1 case), Streptococci (3 cases), Escherichia coli (2 cases), Bacteroides fragilis (1 case), Actinomyces (2 cases), Brucella (3 cases), Mycobacterium tuberculosis (8 cases) and Candida glabrata (1 case). The psoas abscess was primary in 10 cases and secondary in 28 cases. All the patients received an antibiotherapy or an antifungal therapy adapted to the micro-organism in cause, with a drainage of the abscess in 25 cases (surgical in 9 cases and percutaneous in 16 cases). The evolution was favourable in 36 cases. One patient presented recurrences and one patient died. CONCLUSION: The psoas abscess of the adult is characterized by a polymorphe clinical presentation. Germs in cause are very variable.  相似文献   
60.
BACKGROUND: Numerous polymorphisms of the apolipoprotein B (APOB) gene have been described. Particularly, the insertion/deletion (Ins/Del) polymorphism located in the coding part of the signal peptide of apoB, associated with modification of lipid concentrations and the risk of coronary artery disease and/or myocardial infarction (MI), has been reported in the general population. Moreover, conflicting results emerge from the literature and suggest that the effect is context-dependent. In the present study, the first investigation of the Ins/Del polymorphism of the APOB gene in Tunisian patients with MI, we examined a possible association between this polymorphism and MI in a subgroup of the Tunisian population. METHODS: A total of 318 Tunisian patients with MI and 368 healthy controls were included in the study. Genomic DNA was extracted from white blood cells, and the Ins/Del polymorphism was determined by electrophoresis in polyacrylamide gels after PCR amplification. A binary logistic regression analysis was performed to test how the association between MI and Ins/Del polymorphism is independent from confounding factors. RESULTS: A significant difference in genotype distribution and allele frequency was observed between patients and controls. Patients with MI had a frequency of 7.2% for the Del/Del genotype, 39.6% for the Ins/Del genotype, and 53.1% for the Ins/Ins genotype. Controls had a frequency of 3.0% for the Del/Del, 32.1% for the Ins/Del and 64.9% for the Ins/Ins genotype (chi2=12.93, p=0.002). The MI patient group showed a significantly higher frequency of the Del allele compared to controls (27.1% vs. 19.1%; chi2=12.50, p=0.0004). In comparison to the Ins/Ins homozygotes, the odds ratio (95% confidence interval) for MI was 1.51 (1.09-2.07) for Ins/Del heterozygotes and 2.95 (1.40-6.22) for Del/Del homozygotes. In multivariate analysis, age (p=0.001), smoking (p<0.001), hypertension (p=0.001), diabetes mellitus (p<0.001), and dyslipidemia (p=0.01) were independent correlates of the presence of MI, whereas the Ins/Del polymorphism (p=0.330) was not an independent predictor of MI. CONCLUSIONS: The present study shows a significant but not independent association between the Ins/Del polymorphism of the APOB gene and MI in the Tunisian population.  相似文献   
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