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81.
AIMS: To investigate whether prognosis in micropapillary urothelial carcinoma is related to the proportion of the micropapillary component (MPC), and to identify the immunohistochemical features of MPC. METHODS AND RESULTS: This study presents a clinicopathological analysis of 20 patients with micropapillary urothelial carcinoma of the bladder with cystectomy specimens for evaluation. Tumours were stratified on the extent of MPC: focal, <10%; moderate, 10-50%; extensive, >50%; and this was correlated with tumour stage and prognosis. Sixteen males and four females were aged 56-81 years (mean 69 years). All cases had high-grade morphology in the micropapillary carcinoma and typical urothelial carcinoma. All cases with extensive MPC (n = 4) were of a high pathological stage (pT3 or pT4) and died of disease (DOD) or other causes. Eighty percent with moderate MPC (eight of 10 cases) were pT3 or pT4 and 50% DOD or are alive with disease. Eighty-four percent with focal MPC (five of six cases) were pT1 or pTa. In high-stage cases, the most invasive component was MPC. High-stage cases had an 85% risk of being advanced at presentation with micropapillary carcinoma. All pT2 or lower stage cases had micropapillary carcinoma on prior transurethral resections of bladder tumour (TURB). High-stage carcinomas had 30% and 54%, respectively, of surface MPC and urothelial carcinoma in situ, in comparison with 85% and 28% in lower stage carcinomas. Immunohistochemical staining was similarly positive in MPC and typical urothelial carcinoma with cytokeratin (CK)7, CK20, epithelial membrane antigen, carcinoembryonic antigen and cytokeratin 34betaE12. CA125 staining was seen only in MPC in 43% of cases. CONCLUSIONS: Micropapillary urothelial carcinoma is a high-grade carcinoma in which the prognosis is related to the proportion and location of the MPC. Cases with moderate or extensive MPC are at high risk of being advanced at presentation. Cases with <10% MPC and surface MPC have a high chance of detection at an early stage. The morphology and immunohistochemical profile of the MPC suggest that it is a form of glandular differentiation in urothelial carcinoma.  相似文献   
82.

Background

Somatisation disorder (SD) has been reported as common in all ethnic groups, but the estimates of its prevalence have varied and the evidence for its associated factors has been inconsistent.

Purpose

This study seeks to determine the prevalence of SD and its associated factors in multiethnic primary care clinic attenders.

Methods

This cross-sectional study was on clinic attenders aged 18?years and above at three urban primary care clinics in Malaysia. The operational definition of SD was based on ICD-10 criteria for SD for research, frequent attendance, and excluded moderate to severe anxiety and depression. The instruments used were the ICD-10 symptom list, the Hospital Anxiety and Depression Scale, a semi-structured questionnaire, and SF-36.

Results

We recruited 1,763 patients (response rate 63.8%). The mean age of respondents was 44.7?±?15.8?years, 807 (45.8%) were male; there were 35.3% Malay, 30.1% Chinese and 34.6% Indian. SD prevalence was 3.7%; the prevalence in Malay was 5.8%, Indian 3.0% and Chinese 2.1%. Significant associations were found between SD prevalence and ethnicity, family history of alcoholism, blue-collar workers and the physical component summary (PCS) score of SF-36. Multivariate analysis showed that SD predictors were Malay ethnicity (OR 2.7, 95% CI 1.6, 4.6), blue-collar worker (OR 2.0, 95% CI 1.2, 3.5) and impaired PCS score of SF-36 (OR 0.92, 95% CI 0.90, 0.95).

Conclusion

The prevalence of SD was relatively uncommon with the stringent operational criteria used. SD preponderance in blue-collar workers may be attributable to secondary gain from getting sickness certificates and being paid for time off work.  相似文献   
83.
We describe a revised and expanded database on human intermediate filament proteins, a major component of the eukaryotic cytoskeleton. The family of 70 intermediate filament genes (including those encoding keratins, desmins, and lamins) is now known to be associated with a wide range of diverse diseases, at least 72 distinct human pathologies, including skin blistering, muscular dystrophy, cardiomyopathy, premature aging syndromes, neurodegenerative disorders, and cataract. To date, the database catalogs 1,274 manually-curated pathogenic sequence variants and 170 allelic variants in intermediate filament genes from over 459 peer-reviewed research articles. Unrelated cases were collected from all of the six sequence homology groups and the sequence variations were described at cDNA and protein levels with links to the related diseases and reference articles. The mutations and polymorphisms are presented in parallel with data on protein structure, gene, and chromosomal location and basic information on associated diseases. Detailed statistics relating to the variants records in the database are displayed by homology group, mutation type, affected domain, associated diseases, and nucleic and amino acid substitutions. Multiple sequence alignment algorithms can be run from queries to determine DNA or protein sequence conservation. Literature sources can be interrogated within the database and external links are provided to public databases. The database is freely and publicly accessible online at www.interfil.org (last accessed 13 September 2007). Users can query the database by various keywords and the search results can be downloaded. It is anticipated that the Human Intermediate Filament Database (HIFD) will provide a useful resource to study human genome variations for basic scientists, clinicians, and students alike.  相似文献   
84.
Although approximately 20 common genetic susceptibility loci have been identified for breast cancer risk through genome-wide association studies (GWASs), genetic risk variants reported to date explain only a small fraction of heritability for this common cancer. We conducted a four-stage GWAS including 17 153 cases and 16 943 controls among East-Asian women to search for new genetic risk factors for breast cancer. After analyzing 684 457 SNPs in 2062 cases and 2066 controls (Stage I), we selected for replication among 5969 Chinese women (4146 cases and 1823 controls) the top 49 SNPs that had neither been reported previously nor were in strong linkage disequilibrium with reported SNPs (Stage II). Three SNPs were further evaluated in up to 13 152 Chinese and Japanese women (6436 cases and 6716 controls) (Stage III). Finally, two SNPs were evaluated in 10 847 Korean women (4509 cases and 6338 controls) (Stage IV). SNP rs10822013 on chromosome 10q21.2, located in the zinc finger protein 365 (ZNF365) gene, showed a consistent association with breast cancer risk in all four stages with a combined per-risk allele odds ratio of 1.10 (95% CI: 1.07-1.14) (P-value for trend = 5.87 × 10(-9)). In vitro electrophoretic mobility shift assays demonstrated the potential functional significance of rs10822013. Our results strongly implicate rs10822013 at 10q21.2 as a genetic risk variant for breast cancer among East-Asian women.  相似文献   
85.
86.
Spectral indices of cardiac autonomic function in obstructive sleep apnea.   总被引:12,自引:0,他引:12  
M C Khoo  T S Kim  R B Berry 《Sleep》1999,22(4):443-451
Spectral analysis of heart rate variability (HRV) is useful as a noninvasive means of assessing autonomic function in patients with obstructive sleep apnea (OSA). However, standard spectral measures, such as the ratio of low-frequency to high-frequency power (LHR) and normalized high-frequency power (NHFP), can be confounded by the abnormal breathing patterns that occur during sleep. To circumvent this limitation, we employed an autoregressive modeling approach to partition the RR time-series into a component that is correlated with respiration and a respiration-independent component. From these components, we derived two new spectral indices: the modified LHR (MLHR) and the average gain relating respiration to RR changes (GRSA). Six normals and seven OSA patients were studied in relaxed wakefulness and stage 2 sleep; during sleep, the OSA patients were studied without and with continuous positive airway pressure (CPAP) therapy. All four spectral indices showed significant differences between OSA patients and normals in both wakefulness and sleep, although the changes in MLHR and GRSA were substantially larger and less variable: MLHR (p < 0.0003) and GRSA (p < 0.0001) vs. LHR (p < 0.005) and NHFP (p < 0.004). However, in the OSA subjects, LHR and NHFP were unchanged by CPAP. By contrast, CPAP produced a highly significant increase in GRSA (p < 0.0004), as well as a decrease in MLHR (p < 0.03). Thus, by compensating for the effects of breathing pattern differences, MLHR and GRSA unmasked the effects of CPAP therapy, which has been shown in previous studies to reduce sympathetic activity and increase vagal cardiac modulation.  相似文献   
87.
BACKGROUND: Gene-environment interactions play central roles in controlling postnatal maturation of immune function, but their effects on infant vaccine responses are unknown. Genetic variants associated with atopy and the environmental factor of exposure to parental smoking (PS) of tobacco independently alter immune responses. OBJECTIVE: We sought to investigate the hypothesis that genetic variants associated with atopy and their interaction with PS influence infant vaccine responsiveness. METHODS: In 200 infants with parental atopic history, relationships were sought between polymorphisms in the IL-4, IL-4 receptor alpha (IL-4Ralpha), and IL-13 genes; PS; and immune responses to diphtheria/tetanus vaccination. RESULTS: Analyses stratified by PS unmasked negative associations between atopic alleles of these genes and vaccine outcomes. The most consistent involved the IL-4Ralpha 551 QR/QQ genotypes, which were associated with reduced IgG levels (P = .02) and T-cell responses (IFN-gamma, P = .002; IL-10, P = .01; 1L-13, P = .01; IL-5, P = .06) to tetanus toxoid and parallel reductions in polyclonal T-cell responses and innate immune responses in PS-exposed infants. CONCLUSION: PS potentiates suppressive effects of variants in immune response genes in children. These effects are not observed in the absence of this exposure. Ultimately, this finding might have implications for infant vaccination in countries with high smoking rates. It might also have broader implications in relation to environmental toxicology because it demonstrates specific mechanisms through which the developing immune system might be differentially sensitive to low-level toxicant exposures. CLINICAL IMPLICATIONS: PS interacts with genes associated with atopy to impair vaccine responses. These interactions might have vaccine design and public health implications.  相似文献   
88.
The aim of this study was to detect mutations in the genes coding for the low-density lipoprotein receptor and apolipoprotein B in patients of Southeast Asian origin with clinically diagnosed familial hypercholesterolemia (FH) and to relate these findings with the observed lower incidence of coronary heart disease in this part of the world. A total of 86 unrelated patients with FH were selected on clinical grounds, and complete DNA analysis of the low-density lipoprotein (LDL)-receptor and apolipoprotein B (apoB) genes by DGGE and DNA-sequencing was performed. In the majority (73%) of the cohort studied, no mutations could be detected, even after extensive analysis of the LDL-receptor and apoB genes. However, the 22 patients with a mutation had significantly more xanthomas and a higher incidence of coronary heart disease and levels of low-density lipoproteins were also significantly different. There was no correlation between the type of the mutation and lipoprotein levels or clinical signs of atherosclerosis. The fact that the majority of the FH patients studied had no detectable mutation and that this group had a significant milder phenotype, suggests the presence of a third gene in the Southeast Asian population, predominantly leading to a disorder resembling a milder form of FH. A similar, but less frequent, trait has recently been described in a number of European families.  相似文献   
89.
A 12-year retrospective review of severe burn patients who received cultured epithelial autografts (CEA) at the Singapore General Hospital Burns Centre from January 2005 to December 2016 was carried out. During this period, two different surgical modalities were employed to manage these burn injuries. In the earlier period, following early excision of the burn wounds, exposed surfaces were covered with a combination of split thickness skin autografts (STSG) and allografts. Surfaces covered with skin allografts were subsequently debrided of the allo-epidermis in about 3 weeks later, exposing the allodermis with granulating tissues for grafting of CEA; a technique known as the Cuono’s method. In the later period, allograft–autologous micrograft sandwich technique was used to graft on the early excised burns with subsequent CEA grafting. The former and latter groups represented by STSG/C (n = 10) and M/CEA (n = 14) respectively, were compared in terms of clinical profiles, outcomes, allograft/CEA usage and total graft cost. No significant differences were found based on mean age and presence of inhalation burns between the two treatment methods However, percentage total body surface area (TBSA) and Revised Baux Score were significantly higher (p < 0.05) in the M/CEA group compared to the STSG/C group. Differences in clinical outcomes of mortality and length of hospital stay between the 2 groups were statistically insignificant. The average area amount of skin allografts used per patient in the M/CEA group was significantly lower compared to the STSG/C method group which contributed to lower total average cost of grafts used per % TBSA in the M/CEA method group. This might be attributed to the presence of micrografts which seemed to improve stabilization of the wound bed resulting in less operating procedures and improving CEA take. To conclude, the M/CEA method introduced was able to treat more severe burn patients at lower graft costs without compromising critical clinical outcomes significantly.  相似文献   
90.
BACKGROUND: Tubulointerstitial fibrosis is a morphologic hallmark of chronic kidney disease and is a key factor in the prediction of progression to end-stage renal failure. Disruption of tubular basement membrane and interstitial extracellular matrix (ECM) via cytokine-induced alterations in matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs) may be an important mechanism in this process. The presence of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) and their effects on proximal tubular cells may be critical in this process. METHODS: Human proximal tubular cells were cultured in hormonally defined medium. Cells at 80% confluency were exposed to TNF-alpha (0.1 to 100 ng/mL) or IL-1beta (0.1 to 100 ng/mL) or a combination of both for 48 hours. Activity and expression of MMP-9 was examined by gelatin zymography and Western blot analysis. TIMP-1 expression was analyzed by Western blotting. Signaling through cytokine receptors, protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) pathways was investigated. RESULTS: TNF-alpha but not IL-1beta resulted in a dose-dependent increase in the latent form of MMP-9. TIMP-1 was decreased by treatment with either TNF-alpha or IL-1beta. Cotreatment with IL-1beta abolished the induction of MMP-9 but augmented the inhibition of TIMP-1 in the presence of TNF-alpha. Inhibition of PKC provided evidence of the importance of this pathway in mediating the cytokine-induced suppression of TIMP-1 in human kidney (HK-2) cells. Activation of the extracellular signal-regulated protein kinase (ERK1/2) MAPK mediated the up-regulation of MMP-9 by TNF-alpha whereas p38 was found to be involved in the IL-1beta-mediated inhibition of TNF-alpha-stimulated MMP-9. CONCLUSION: The differential effects of TNF-alpha and IL-1beta on proximal tubular MMP-9 and TIMP-1 expression are mediated through the TNF-RI, the IL-1-RI and the different signaling pathways of PKC, ERK1/2, and p38 MAPK. These findings may provide new insights into the role of proinflammatory cytokines TNF-alpha and IL-1beta in the development and possible therapeutic intervention in tubulointerstitial fibrosis.  相似文献   
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