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61.
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.  相似文献   
62.
PURPOSE: Squamous cell carcinoma (SCC) and adenocarcinoma of the lung are currently subject to similar treatment regimens despite distinct differences in histology and epidemiology. The aim of this study is to identify a molecular target with diagnostic and therapeutic values for SCC. EXPERIMENTAL DESIGN: Genes specifically up-regulated in SCC were explored through microarray analysis of 5 SCCs, 5 adenocarcinomas, 10 small cell lung carcinomas, 27 normal tissues, and 40 cancer cell lines. Clinical usefulness of these genes was subsequently examined mainly by immunohistochemical analysis. RESULTS: Seven genes, including aldo-keto reductase family 1, member B10 (AKR1B10), were identified as SCC-specific genes. AKR1B10 was further examined by immunohistochemical analysis of 101 non-small cell lung carcinomas (NSCLC) and its overexpression was observed in 27 of 32 (84.4%) SCCs and 19 of 65 (29.2%) adenocarcinomas. Multiple regression analysis showed that smoking was an independent variable responsible for AKR1B10 overexpression in NSCLCs (P < 0.01) and adenocarcinomas (P < 0.01). AKR1B10 staining was occasionally observed even in squamous metaplasia, a precancerous lesion of SCC. CONCLUSION: AKR1B10 was overexpressed in most cases with SCC, which is closely associated with smoking, and many adenocarcinoma cases of smokers. These results suggest that AKR1B10 is a potential diagnostic marker specific to smokers' NSCLCs and might be involved in tobacco-related carcinogenesis.  相似文献   
63.
中药与日本汉方药原植物的差异比较及原因分析   总被引:1,自引:1,他引:1  
依据 2000年版《中国药典》和第十四改《正日本药局方》收载植物类生药品种 ,列表比较了中药与日本汉方药原植物的差异 ,并对产生差异的现象和原因进行了分析和探讨。  相似文献   
64.
65.

Purpose:

To identify and characterize sickle cell disease (SCD)‐related changes in the composition of mandibular bone marrow using qMRI relaxometry histograms.

Materials and Methods:

Thirteen SCD patients and 17 controls underwent brain MR imaging with the mixed turbo spin‐echo (TSE) pulse sequence at 1.5T. The mandible was manually segmented and divided into body, angle, ramus, and condyle. T1 and T2 histograms of each mandible were modeled with Gaussian functions. The relaxation time histogram peaks were calculated, and the number of monomodal versus bimodal curves was compared.

Results:

SCD patients exhibited monomodal distributions on both T1 and T2 histograms, consistent with a composition of predominantly red hematopoietic marrow. Eighty‐eight percent of mandibles in control subjects exhibited a bimodal distribution in T1 and all showed a bimodal distribution in T2, indicating mixed but predominantly yellow marrow composition. The second peak in control subjects was shorter in T1 and longer in T2, consistent with yellow marrow composition.

Conclusion:

Instead of physiological fatty replacement, SCD patients exhibit red marrow persistence in the mandible, likely due to the increased demand for hematopoiesis. This phenomenon can be manifested by a monomodal curve in both T1 and T2 relaxometric histograms. J. Magn. Reson. Imaging 2013;37:1182–1188. © 2012 Wiley Periodicals, Inc.  相似文献   
66.
Ribonucleotides incorporated in the genome are a source of endogenous DNA damage and also serve as signals for repair. Although recent advances of ribonucleotide detection by sequencing, the balance between incorporation and repair of ribonucleotides has not been elucidated. Here, we describe a competitive sequencing method, Ribonucleotide Scanning Quantification sequencing (RiSQ-seq), which enables absolute quantification of misincorporated ribonucleotides throughout the genome by background normalization and standard adjustment within a single sample. RiSQ-seq analysis of cells harboring wild-type DNA polymerases revealed that ribonucleotides were incorporated nonuniformly in the genome with a 3′-shifted distribution and preference for GC sequences. Although ribonucleotide profiles in wild-type and repair-deficient mutant strains showed a similar pattern, direct comparison of distinct ribonucleotide levels in the strains by RiSQ-seq enabled evaluation of ribonucleotide excision repair activity at base resolution and revealed the strand bias of repair. The distinct preferences of ribonucleotide incorporation and repair create vulnerable regions associated with indel hotspots, suggesting that repair at sites of ribonucleotide misincorporation serves to maintain genome integrity and that RiSQ-seq can provide an estimate of indel risk.  相似文献   
67.
68.
Toxic epidermal necrolysis (TEN) is a rare condition, causing life‐threatening adverse cutaneous reactions. TEN occurrence after bone marrow transplantation (BMT) is a well‐known phenomenon; however, to date, only a few cases have been reported in the published work. Here, we describe the case of a 53‐year‐old woman who experienced TEN after undergoing allogenic BMT for malignant lymphoma. Skin erosion spread across a maximum of 70% of the body surface area and severe mucosal lesions developed. Steroid pulse therapy, plasma apheresis and immunoglobulin therapy were administrated, which resulted in the complete resolution of TEN. However, she developed hemophagocytic lymphohistiocytosis and died 38 days after BMT, owing to rupture of the lower digestive tract complicated by multi‐organ failure. In our case, engraftment failure occurred, and the peripheral white blood cell count was less than 100/μL during the TEN course, suggesting that the presence of only a few immune cells could cause TEN. Our findings showed that high mortality rates and widespread skin erosion could be regarded as the most important characteristics of TEN occurring after BMT.  相似文献   
69.
Ethnic differences in the profiles of hypertension and cardiovascular risk have been reported between Asians and Westerners. However, blood pressure (BP) profiles and the risk factors for cardiovascular disease might differ even among different Asian populations because of the diversity of cultures, foods, and environments. We retrospectively examined differences in 24‐h BP profiles between 1051 Japanese (mean age, 62.5 ± 12.4 years; medicated hypertension, 75.7%) and 804 Thai (mean age, 56.9 ± 18.5 years; medicated hypertension, 65.6%) by using the Japanese and Thai ambulatory BP monitoring (ABPM) databases, in order to check the BP control status in treated hypertensives and to inform the clinical diagnosis of hypertension. The two populations had similar office systolic BP (SBP) (142.7 ± 20.0 vs 142.3 ± 20.6 mm Hg, p = .679). However, the Japanese population had higher 24‐hr average and daytime SBP, and the Thai population had higher nighttime SBP even after adjusting for cardiovascular risk factors (all p < .05). Greater morning BP surge was observed in Japanese (31.2 vs 22.8 mm Hg, p < .001). Regarding nocturnal BP dipping status, the prevalence of riser status (higher nighttime than daytime SBP) was higher in the Thai population (30.5% vs 10.9%). These findings suggest that a substantial difference in 24‐hr BP profiles exists between even neighboring countries in Asia.  相似文献   
70.
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