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121.
BackgroundA surveillance program was performed in colorectal cancer (CRC) patients after surgery, to diagnose asymptomatic recurrence.AimsTo assess whether 18-FDG positron emission tomography/CT (PET/CT) improved the detection of recurrence during a 3-year follow-up.MethodsA multicentre, two-arm randomised prospective trial comparing different 36-month follow-up strategies. Complete colonoscopy was performed at baseline and after 3 years and clinical exams with imaging every 3 months. The conventional arm (A) received carcinoembryonic antigen, liver echography, and alternated between lung radiography and computed tomography (CT) scans. The experimental arm (B) received PET/CT.ResultsA total of 365 patients with colon (79.4%) or rectal cancer (20.6%), stages II (48.2%) or III (50.8%), were enroled in this study. At 36 months, intention-to-treat analysis revealed recurrence in 31 (17.2%) patients in arm A and 47 (25.4%) in arm B (p = 0.063). At 3 years, 7 of 31 relapses (22.5%) in arm A were surgically treated with curative intent, compared to 17 of 47 (36.2%) in arm B (p = 0.25). The rates of recurrence and new cancers were higher in arm B than arm A (p = 0.038).ConclusionsPET/CT follow-up every 6 months did not increase the rate of recurrence at 3 years or the rate of surgically treated recurrence compared with conventional follow-up.  相似文献   
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We analyzed herein whether members of the tetraspanin superfamily are involved in human immature dendritic cell (DC) functions such as foreign antigen internalization, phagocytosis, and cell migration. We show that CD63, CD9, CD81, CD82, and CD151 are present in immature DCs. Whereas CD9 and CD81 are mostly expressed at the cell surface, CD63 and CD82 are also located in intracellular organelles. Complexes of monoclonal antibody (Mab) FC-5.01-CD63 or Fab-5.01-CD63 were rapidly translocated "outside-in" and followed the endocytic pathway through early endosomes and lysosomes, reaching major histocompatibility complex (MHC) class II-enriched compartments (MIICs) in less than one hour. Internalization of CD63 was also observed during Saccharomyces cerevisiae phagocytosis. Moreover, an association of CD63 with the beta-glycan receptor dectin-1 was observed. Mabs against CD9, CD63, CD81, and CD82 enhanced by 50% the migration induced by the chemokines macrophage inflammatory protein-5 (MIP-5) and MIP-1alpha. Concomitantly, Mabs against CD63 and CD82 diminished the surface expression of CD29, CD11b, CD18, and alpha5 integrins. By immunoprecipitation experiments we found that CD63 associated with integrins CD11b and CD18. These results suggest that CD9, CD63, CD81, and CD82 could play a role in modulating the interactions between immature DCs and their environment, slowing their migratory ability. However, only CD63 would intervene in the internalization of complex antigens.  相似文献   
124.
Unlike previously reported cases with total protein 4.2 deficiency due to mutations in the EPB42 gene, we describe a total deficiency in protein 4.2 with normal EPB42 alleles. Hereditary spherocytosis (HS) was observed in a Japanese woman (unsplenectomized) and her daughter (splenectomized). The mother showed a partial deficiency in band 3 and a proportional reduction in protein 4.2. She was heterozygous for a novel allele of the EPB3 gene, allele Okinawa, which contains the two mutations that define the Memphis II polymorphism (K56E, AAG → GAG, and P854L, CCG → CTG) and, additionally, the mutation: G714R, GGG → AGG, located in a highly conserved position of transmembrane segment 9. The latter change was responsible for HS. In trans to allele Okinawa, the daughter displayed allele Fukuoka: G130R, GGA → AGA, an allele known to alter the binding of protein 4.2 to band 3. The daughter presented with a more pronounced decrease of band 3, and lacked protein 4.2, resulting in aggravated haemolytic features. Although the father was not available for study, heterozygosity for allele Fukuoka has been documented in another individual who showed no clinical or haematological signs, and a normal content of band 3. We suggest that band 3 Okinawa binds virtually all the protein 4.2 in red cell precursors, band 3 Fukuoka being unable to do so, and that the impossibility of band 3 Okinawa incorporation into the membrane leads to degradation of the band 3 Okinawa protein 4.2 complex. In contrast, band 3 Fukuoka, free of bound protein 4.2, could then incorporate normally into the bilayer. Thus, protein 4.2 would not appear in the daughter's red cell membrane.  相似文献   
125.
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Pulmonary cavitary lesions in the absence of concomitant comorbidities are an uncommon and often confusing manifestation of sarcoidosis. We retrospectively reviewed the clinical and high-resolution computed tomography (HRCT) characteristics and the natural history of a series of 23 patients with pulmonary cavitary lesions found on HRCT extracted from a large cohort of patients with pulmonary sarcoidosis. The estimated prevalence of cavitary sarcoidosis was 2.2%. Cavitary lesions developed in patients with severe and active sarcoidosis (serum angiotensin-converting enzyme [SACE] > or =2 times the upper limit of normal range: 63.6%). Twelve (52.2%) patients had evidence of radiographic stage IV, 9 of whom (75%) had persistently increased SACE. As found on HRCT, cavitary lesions were multiple in 21 patients (91.3%), including 5 patients with 10 or more cavities. The size of cavitary lesions was variable, with a median diameter of 20 mm (range, 11-100 mm). Follow-up was available for 20 patients with a median follow-up of 6.25 years (range, 6 months to 15 years). Seven patients (35%) experienced some type of complication related to cavitary lesions, including 6 episodes of hemoptysis in 5 patients and aspergilloma occurrence in 3 patients. As seen on HRCT, the evolution of the number and size of cavitary lesions was variable, with a complete resolution of the largest cavitary lesion in only 5 patients (25%). During follow-up, wall thickening was always associated with a further infectious complication. In summary, cavitary lesions are rare in pulmonary sarcoidosis and usually occur in active and severe sarcoidosis. Their evolution is unpredictable, and complications are frequent.  相似文献   
127.
BACKGROUND: Peripheral C4A treatment (cerebral and peripheral vasotherapeutics) and especially Ginkgo biloba extracts are prescribed for a number of symptoms, particularly memory impairment, in elderly patients. It is postulated that because of its pharmacological actions, this treatment could prevent the decline of cognitive function, but no studies have been published to date to test its efficacy in prevention of Alzheimer's disease. The potential association between use of C4A treatments, in particular EGb 761 (standardized Ginkgo biloba extracts), and dementia of the Alzheimer type was investigated. METHODS: A case-control study was nested in a cohort of 1462 community-dwelling elderly women aged over 75 years. Sixty-nine women with Alzheimer-type dementia were compared with 345 paired women whose cognitive function remained normal. This study involved women whose cognitive function was evaluated at baseline by use of Pfeiffer's test and whose medication history was taken. The onset of cognitive impairment was investigated over a 7-year follow-up period. In order to study the factors associated with the onset of dementia, the data concerning women with a score of > or = 8 on Pfeiffer's test at inclusion, indicating normal cognitive function, were analyzed. RESULTS: A multivariate analysis including potential confounding factors showed that fewer women who developed Alzheimer's dementia had been prescribed C4A treatment (including EGb 761) for at least 2 years (odds ratio = 0.31, 95% confidence interval = 0.12-0.82, p =.018). Figures for EGb 761 alone were similar but did not reach statistical significance (odds ratio = 0.38, 95% confidence interval = 0.08-1.76, p =.22). CONCLUSION: These results suggest that C4A treatment may reduce the risk of developing Alzheimer's dementia in elderly women. The potential preventive effect of C4A treatments, including EGb 761, requires further examination. To establish a causal relationship, these findings have to be confirmed with prospective studies.  相似文献   
128.
The pathogenesis of follicular lymphoma is a multi-hit process progressing over many years through the accumulation of numerous genetic alterations. Besides the hallmark t(14;18), it is still unclear which other oncogenic hits contribute to the early steps of transformation and in which precursor stages these occur. To address this issue, we performed high-resolution comparative genomic hybridization microarrays on laser-capture micro-dissected cases of follicular lymphoma in situ (n=4), partial involvement by follicular lymphoma (n=4), and duodenal follicular lymphoma (n=4), assumed to represent, potentially, the earliest stages in the evolution of follicular lymphoma. Cases of reactive follicular hyperplasia (n=2), uninvolved areas from follicular lymphoma in situ lymph nodes, follicular lymphoma grade 1–2 (n=5) and follicular lymphoma grade 3A (n=5) were used as controls. Surprisingly, alterations involving several relevant (onco)genes were found in all entities, but at significantly lower proportions than in overt follicular lymphoma. While the number of alterations clearly assigns all these entities as precursors, the pattern of partial involvement by follicular lymphoma alterations was quantitatively and qualitatively closer to that of follicular lymphoma, indicating significant selective pressure in line with its faster rate of progression. Among the most notable alterations, we observed and validated deletions of 1p36 and gains of the 7p and 12q chromosomes and related oncogenes, which include some of the most recurrent oncogenic alterations in overt follicular lymphoma (TNFRSF14, EZH2, MLL2). By further delineating distinctive and hierarchical molecular and genetic features of early follicular lymphoma entities, our analysis underlines the importance of applying appropriate criteria for the differential diagnosis. It also provides a first set of candidates likely to be involved in the cascade of hits that pave the path of the various progression phases to follicular lymphoma development.  相似文献   
129.

Background

Liver stiffness evaluation (LSE) by Fibroscan is now widely used to assess liver fibrosis in chronic hepatitis C. Liver steatosis is a common lesion in chronic hepatitis C as in other chronic liver diseases, but its influence on LSE remains unclear. We aimed to precisely determine the influence of steatosis on LSE by using quantitative and precise morphometric measurements of liver histology.

Methods

650 patients with chronic hepatitis C, liver biopsy, and LSE were included. Liver specimens were evaluated by optical analysis (Metavir F and A, steatosis grading) and by computerized morphometry to determine the area (%, reflecting quantity) and fractal dimension (FD, reflecting architecture) of liver fibrosis and steatosis.

Results

The relationships between LSE and liver histology were better described using morphometry. LSE median was independently linked to fibrosis (area or FD), steatosis (area or FD), activity (serum AST), and IQR/LSE median. Steatosis area ≥4.0 % induced a 50 % increase in LSE result in patients with fibrosis area <9 %. In patients with IQR/LSE median ≤0.30, the rate of F0/1 patients misclassified as F ≥ 2 by Fibroscan was, respectively for steatosis area <4.0 and ≥4.0 %: 12.6 vs 32.4 % (p = 0.003). Steatosis level did not influence LSE median when fibrosis area was ≥9 %, and consequently did not increase the rate of F ≤ 3 patients misclassified as cirrhotic.

Conclusion

A precise evaluation of liver histology by computerized morphometry shows that liver stiffness measured by Fibroscan is linked to liver fibrosis, activity, and also steatosis. High level of steatosis induces misevaluation of liver fibrosis by Fibroscan.  相似文献   
130.
This FranceCoag network study assessed 33 patients with congenital factor XIII (FXIII) deficiency presenting FXIII levels <10 iu/dl. Diagnosis was based on abnormal bleeding in 29 patients, a positive family history in 2, recurrent miscarriages in 1 and was fortuitous in 1. Eighteen patients (62·1%) presented life-threatening umbilical or intracranial haemorrhages (ICH). Seven of the 15 patients who experienced ICH were diagnosed but untreated, including 3 with secondary neurological sequelae. All pregnancies without prophylaxis (26/26) led to miscarriages versus 3/16 with prophylaxis. In patients exhibiting FXIII levels <10 iu/dl, prophylaxis could be discussed at diagnosis and at pregnancy. Further controlled prospective studies are needed.  相似文献   
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