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11.
Glomeruli of archival renal biopsies, stored frozen at -70 degrees C, from three patients with amyloid were examined by protein A-gold immunoelectron microscopy. In one with both fibrillar and granular deposits from a 'skin popper' drug abuser, the granular deposits were labeled with anti-IgG, while the fibrillar deposits were labeled with anti-amyloid-A (AA) protein and amyloid P component (AP), suggesting coexisting immune complex disease and AA due to different, but possibly related, pathogenesis. In studies using double-label immunostaining of primary amyloidosis-lambda light chain type (AL) and AA associated with Crohn's disease, AP occurred as widely separated single units along the amyloid fibrils and represented 1.5% and 6.5% of the total gold label in AL and AA, respectively, while the major fibril protein was labeled in single rows, similar to beads on a string. Fibrillar aggregates in the capillary lumens were labeled similarly by antisera to the major protein and AP and appeared to be contiguous with the fibrillar deposits at the glomerular basement membrane (GBM)-luminal interface, suggesting intravascular fibrillogenesis.  相似文献   
12.
A total of 3,349 serum samples were screened by the immunofluorescence (IF) method for antibody to human T-cell leukemia virus type I (HTLV-I). Only 9 of 2,409 specimens from selected individuals, blood bank donors, patients with encephalitis-meningitis, and human immunodeficiency virus antibody-positive homosexual or bisexual men were reactive by IF. In addition, 940 serum samples from intravenous drug abusers were tested by IF and also by an HTLV-I enzyme immunoassay (EIA) method. Of these, 222 (24%) were positive for both HTLV-I and HTLV-II antigens by IF, and 191 of these 222 were also reactive in the HTLV-I EIA. Of the 31 IF-positive, EIA-negative serum samples, 20 exhibited optical density readings greater than or equal to 70% of the positive cutoff in the EIA, and 29 samples reacted with 1 or more bands in the Western blot (immunoblot) test. An additional 10 specimens that were EIA negative reacted only with HTLV-I by IF. Differences in staining morphology and in reactions on HTLV-I and HTLV-II antigens before and after absorption of the serum specimens with HTLV-I and HTLV-II-infected cell pellets revealed six distinct serological patterns by IF. These results indicate that infections by HTLV-I or by another closely related retrovirus(es) occur in California. Further studies utilizing statistically valid sampling methods are needed to estimate true prevalence rates among various groups. IF and Western blot tests should supplement the EIA method to maximize sensitivity and specificity of test procedures.  相似文献   
13.
Spindle-shaped cells from Kaposi's sarcoma lesions (AIDS-KS cells) were cultured for long periods in the presence of conditioned medium from activated CD4-positive T cells (HTLV-II infected transformed nonvirus producer) and characterized under in vitro conditions. To investigate a possible vascular origin, AIDS-KS cells were analyzed for the presence of smooth muscle alpha-actin, a differentiation marker for vascular smooth muscle cells. Immunofluorescence studies using a monoclonal antibody for smooth muscle alpha-actin demonstrated positive staining of the AIDS-KS cells (KS-3 and KS-4) but not by endothelial cells or fibroblasts. Northern blot analysis using an oligonucleotide probe unique for human smooth muscle alpha-actin indicated the expression of this gene by AIDS-KS cells. Similar analysis of biopsies from the KS lesion showed that in addition to the staining of smooth muscle cells associated with the blood vessels, the tumor-related spindle cells also stained positively. These cells were also analyzed for the expression of different growth factor genes. The platelet-derived growth factor (PDGF) A-chain gene was expressed at a moderate level. The insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-2 (IGF-2) genes were not overexpressed in relation to control cells. These data suggest that the analyzed AIDS-KS cells may be smooth muscle-like cells and therefore of vascular origin. Based on these results as well as previous reports, we speculate that cells of the immune system may regulate growth of cells in the vascular wall by a novel pathway.  相似文献   
14.
Leukemic peripheral blood lymphocytes from individuals infected with the human T-cell leukemia/lymphoma virus (HTLV) were found to express little or no viral RNA before being put into tissue culture. Within 24-48 hr, viral RNA expression increased at least four- to eightfold. Established HTLV-infected cell lines constitutively express viral RNA. Southern blots of DNA from HTLV-infected cells digested with the methylation-sensitive restriction enzyme HpaII showed that the proviral DNA was methylated in all of the uncultured peripheral blood cells tested. In contrast, no proviral methylation was detected in any of the cell lines examined, suggesting a functional correlation between methylation and viral RNA expression. However, DNA from HTLV-infected lymphocytes cultured for 48 hr (by which time increases in viral RNA expression are evident) did not differ detectably with respect to proviral DNA methylation from uncultured cells, suggesting that the increase in viral RNA expression after short-term culture is mediated by mechanisms independent of changes in DNA methylation.  相似文献   
15.
Mucosal leishmaniasis of the upper respiratory tract is usually associated with the visceral form or is found in immunosuppressed individuals. This report presents a case of isolated mucosal leishmaniasis in an immunocompetent patient, whose diagnosis mainly rested on histology and positive polymerase chain reaction result for Leishmania donovani in the laryngeal tissue. A 59-year-old man, who never lived outside Italy, showed a subglottic mucosal polypoid-like lesion. The typical morphological picture and positive polymerase chain reaction result for L donovani by DNA extracted from laryngeal biopsy specimens allowed the diagnosis of mucosal leishmaniasis. Specific amphotericin B therapy was started, resulting in clinical and endoscopic improvement. Increased knowledge about the histological and molecular tissue analysis of Leishmania enhances the diagnostic testing for mucosal leishmaniasis, as primary mucosal leishmaniasis may occur in both immunosuppresed and immunocompetent patients who travel to or reside in areas endemic for Leishmania.  相似文献   
16.
BACKGROUND: The review aimed to compare the effectiveness, safety and acceptability of vasectomy techniques for male sterilization. METHODS: We searched five computerized databases and reference lists of relevant articles and book chapters for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) comparing vasectomy techniques. Two reviewers independently extracted data from eligible articles. RESULTS: Two poor-quality trials compared vas occlusion with clips versus a conventional technique, and four poor-quality trials examined vas irrigation with water versus no irrigation or irrigation with euflavine. No significant differences regarding the primary outcome of time to azoospermia were found. However, one trial reported fewer median number of ejaculations to azoospermia with euflavine rather than water irrigation. An interim report of a high-quality trial comparing vasectomy with and without fascial interposition found more azoospermia with fascial interposition but also more surgical difficulties. CONCLUSIONS: No conclusions can be reached regarding the effectiveness, safety and acceptability of vas occlusion techniques or vas irrigation since only low-quality, underpowered studies were available. Fascial interposition had improved vasectomy success but also increased surgical difficulty. High-quality, adequately reported RCTs are required. More work is also needed in the standardization of follow-up protocols, evaluation of vasectomy success and failure, recanalization and analytical methods.  相似文献   
17.
Renal complications of B-cell dyscrasias   总被引:2,自引:0,他引:2  
  相似文献   
18.
Birth weight has long been a focus of study by epidemiologists and human biologists, because it reflects the quality of the intrauterine environment and may be used as a predictor of future growth and development. Comparisons of Black and White neonates in the USA have consistently shown differences in birth weight. Confounding variables are a major problem in any such investigation, especially socio-economic status which is highly correlated with race in the USA. This study was distinctive in the sampling of one socio-economic stratum (low income), and the use of five anthropometric measures in addition to birth weight. The goals of this study were as follows: to determine if there were differences in body size and body composition at birth in Black and White neonates of low socio-economic status (SES), and to investigate what variables might account for any observed variability. The sample consisted of full term Black and White neonates of low SES (n = 323) born in Albany, NY (1986-1997). Birth weight, length, head and arm circumference, and subscapular and triceps skinfolds were compared. Race was determined through maternal self-identification. White neonates were significantly larger than Black neonates in birth weight, length and head circumference. Among female neonates none of the anthropometric dimensions differed between Blacks and Whites. Among male neonates, Whites were significantly larger than Blacks in birth weight, length, head and arm circumferences. Principal components analysis reduced the six anthropometric dimensions to two summary measures: body size and composition. When controlling for social and biological variables, race and sex were significant predictors of body composition, but not body size. Interpretation of results and possible causal relationships are discussed.  相似文献   
19.
INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital systemic angiodysplasia with multiple vascular malformations in the skin, gastrointestinal tract and, less often, in other internal organs and the brain. CASE REPORT: A 36-year-old man with past history of BRBNS was admitted to our hospital for progressive dyspnea and fatigue. Primary pulmonary hypertension (PPH) was diagnosed. He then developed acute abdominal pain and dyspnea, dying in a few hours due to sudden cardiac arrest. Postmortem examination demonstrated angiomatous lesions located in the skin, small bowel, heart, lungs, liver and thyroid. The lesions were slightly raised, soft and compressible and microscopically consisted of dilated vascular channels lined by a flattened endothelium. The vascular wall was formed by several layers of smooth muscle cells, intermixed with abundant aggregates of elastic lamellae and thin collagen fibers. Luminal thrombi were a frequent finding. In the small bowel, we identified the presence of an abnormally large artery directly opening into a thin-walled venous channel. The most striking finding in the lungs was the presence of thrombi of varying age in the lumen of segmental and elastic arteries, as well as muscular arteries and arterioles. Severe medial hypertrophy of muscular arteries and muscolarization of arterioles were also present. Intimal proliferative lesions and plexiform lesions were never observed. CONCLUSION: The pulmonary findings are consistent with recurrent thromboembolic events from shunts in the visceral lesions. To our knowledge, this is the first report of BRBNS with visceral arterovenous (AV) fistulae complicated by thromboembolic pulmonary hypertension (PH).  相似文献   
20.
Characterization of tissue amyloid by immunofluorescence microscopy   总被引:6,自引:0,他引:6  
Immunohistochemical classification of amyloid type was possible in 44 of 50 (88%) patients as judged by the concordance of immunofluorescence, clinical, serum, and urine immunoelectrophoresis, and bone marrow data. In frozen tissue sections incubated with a panel of antisera monospecific for immunoglobulin heavy chains, kappa and lambda light chains, and amyloid-A-related protein, the amyloid was classified as AL in 20 and AA in 24. In 6 patients the amyloid could not be classified because of the absence of reactivity in 2 and overlap staining in 4. The findings indicate that routine immunofluorescence examination of diagnostic biopsies is an important adjunct in the classification of amyloid.  相似文献   
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