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Multimodality medical imaging enables measurement of the three-dimensional spatial distribution of a radiolabeled aerosol within the lung. Using a conceptual spatial morphological model these data may be transformed to provide information on deposition per airway generation. This methodology has been used to study the intrapulmonary deposition patterns of two formulations of a metered dose inhaler and two nebulizers in control subjects. The nebulizer study has also been stimulated using a computer model of deposition. The comparison between derived experimental results and those from computer modeling shows areas of agreement, although there are also areas of discrepancy. The new methodology has considerable potential value in the fields of inhalation therapy and deposition modeling, although more detailed validation is still required.  相似文献   
3.
In order to examine the immunopathogenesis of hepatitis C virus (HCV)-related liver injury in renal-transplant patients, intra-hepatic cytokine profiles were examined in 38 liver biopsies from 38 patients by measuring messenger RNA (mRNA) concentrations by a real-time PCR method of a Th1 cytokine (i.e., interferon (IFN)-gamma), a Th2 cytokines (i.e., interleukine (IL)-10), a proinflammatory cytokine (i.e., IL-8), and a potent fibrogenic factor (transforming growth factor [TGF]-beta). There was no significant difference in TGF-beta, IFN-gamma, IL-10, or IL-8 levels of expression according to liver-activity grade, liver-fibrosis stage, the concentration of HCV RNA at liver biopsies, or the HCV genotype. However, IFN-gamma/beta-actin mRNA concentration was higher than the IL-10/beta-actin mRNA concentration in patients with F3 Metavir score. Median IFN-gamma/beta-actin mRNA concentration tended to be higher in patients with A3 and A4 Metavir activity grades compared with those with A0 and A1 activity grades. There was a significant correlation between the duration of HCV infection and both TGF-beta/beta-actin (r(2)=0.19, P=0.04) and IL-8/beta-actin mRNA concentrations (r(2)=0.19, P=0.03). IFN-gamma/beta-actin mRNA concentration also increased according to the duration of HCV (r(2)=0.19, P=0.07). Finally, there was a significant correlation between the duration of HCV infection and liver fibrosis stage (r(2)=0.17, P=0.045). Intrahepatic Th1 cytokine profile seems to be predominant in patients with extensive fibrosis and activity scores, suggesting that it might be responsible for liver injury in renal transplant patients.  相似文献   
4.
BACKGROUND: To date, there is no safe and efficient treatment of hepatitis C virus (HCV) infection after renal transplantation. Recently, there were encouraging reports after using amantadine in HCV-positive immunocompetent patients. OBJECTIVES: In an open pilot study, we evaluated the efficacy and the safety of amantadine monotherapy in 8 HCV positive renal-transplant patients with chronic active hepatitis and increased alanine aminotransferase (ALT) levels. RESULTS: After 6 months of amantadine therapy (200 mg per day), there were no decrease in HCV viremia (5.87 +/- 0.37 log copies/ml at M6 versus 5.71 +/- 0.5 log copies/ml at baseline; P > 0.05). However, we found a significant decrease in ALT activity (71 +/- 17 IU/l at M6 versus 100 +/- 9 IU/l at baseline; P = 0.04), whereas the decrease in aspartate aminotransferase activity did not reach statistical significance. There were no significant changes in liver histology. The clinical and biological tolerance was very good. Finally, there were a significant decrease in cyclosporine A whole blood trough levels during therapy. CONCLUSIONS: Our study is the first one to demonstrate that amantadine monotherapy lack of efficacy in HCV renal-transplant patients. It is able to improve liver enzymes but it has no impact neither upon HCV viremia nor upon liver histology.  相似文献   
5.
Effects of long-term lamivudine therapy in renal-transplant patients.   总被引:1,自引:0,他引:1  
BACKGROUND: Following renal transplantation (RT), chronic immunosuppression is associated in hepatitis B virus (HBV) (+) patients with a flare-up of the disease, which might be harmful in the long term. OBJECTIVES: We report on the effect of long-term lamivudine therapy given at an initial daily dose of 100mg in 18 HBV (+) RT patients. RESULTS: When lamivudine therapy was commenced, 14 patients (77%) had an increase in their aspartate (AST) and alanine (ALT) aminotransferase levels. During a mean follow-up, under treatment, of 36.5 +/- 3.5 months (up to 66 months), 10 patients (55%) had a sustained partial (HBV DNA < 4 x 10(5)copies/ml) (n = 4) or complete (HBV DNA < 400 copies/ml) (n = 6) virological response. Overall, 12 virological breakthroughs were observed. Of those who were HBe Ag(+) prior to lamivudine therapy (n = 4), one seroconverted to HBe Ab during therapy. At the last follow-up, AST and ALT levels were normal in 13 patients. When liver biopsy was repeated during treatment (n = 15), the virological responders showed a significant decrease in total Knodell score from 10 +/- 0.6 to 7 +/- 1 (P = 0.04), but no significant change in the stage of fibrosis. Conversely, in those patients with high HBV DNA titers, there were no significant changes in the total Knodell score or in the grade of fibrosis. CONCLUSION: In conclusion, lamivudine therapy is safe in HBV(+)ve renal-transplant patients. However, even if the full and partial virological response rates are still high (55%) in the long term, relapse or primary non-responses occur. The implementation of alternative efficient strategies is warranted.  相似文献   
6.

Background

Patients with inflammatory bowel disease (IBD) – ulcerative colitis (UC) and Crohn’s disease (CD) have an elevated risk of developing colorectal carcinoma (CRC). Major risk factor in IBD patients is the continuous chronic inflammation leading to development of dysplasia and carcinoma. Nevertheless, other types of non-conventional but suspicious mucosal changes serrated change/dysplasia, NOS and villous hypermucinous change, have also been reported in IBD patients. Preneoplastic potential of these lesions is still not well elucidated.

Aims

The aim of this study was identification of IBD-associated CRCs focusing on finding related precursor lesions in the surgical specimen or in archival biopsy samples followed by a detailed morphological, immunohistochemical and molecular evaluation. For the purpose of the study the mucosal lesions were divided into conventional IBD-associated dysplasia and non-conventional lesions that were merged under a provisory term of putative preneoplastic lesions (PPL).

Methods

A total of 309 consecutive IBD colectomy specimens diagnosed during a 10-year period were reviewed. Detailed morphological evaluation, immunohistochemical analysis of mismatch repair (MMR) proteins, p53 and O6-methylguanine DNA methyltransferase (MGMT) expression and molecular analysis for KRAS, NRAS and BRAF gene mutation were performed in the retrieved CRC cases as well as in the detected dysplasia and PPLs of these patients.

Results

We identified 11 cases of morphologically heterogenous IBD-associated CRCs, occurring in 5 males and 6 females, aged 26–79 years (mean 44 years). A total of 22 mucosal lesions were revealed in 8 CRC patients comprising conventional IBD-associated dysplasia (4 lesions), PPLs as serrated change/dysplasia NOS (11 lesions), villous hypermucinous change (5 lesions), and two true serrated lesions (one sessile serrated adenoma and one traditional serrated adenoma). More than one type of lesion was found in 6 patients. Seven CRC cases harbored mutation of KRAS/NRAS and one case of BRAF. Two patients with KRAS-mutated CRC showed the same mutation in PPL in the same specimen (one serrated change NOS and one TSA with high-grade dysplasia). Similarly, one BRAF-mutated carcinoma case presented the same mutation in serrated change/dysplasia, NOS in the same specimen. Of the CRCs, two showed deficient MMR system profile, six presented with loss of MGMT expression, and six showed aberrant p53 expression. PPLs showed deficient MGMT expression (14 cases) and aberrant p53 (10 cases) as well.

Conclusion

IBD-associated CRCs are very heterogeneous entities. Besides conventional IBD-related dysplasia, other types of mucosal lesions may be associated with long lasting IBD and CRC e.g. villous hypermucinous change and serrated change/dysplasia, NOS. Since these lesions share certain genetic or immunohistochemical changes with the related CRC, a suspicion is raised that these lesions may also have preneoplastic potential. Awareness of these changes is necessary to prevent their missing and under-reporting, and further studies of these lesions should be carried out.  相似文献   
7.
Currently, there are 18 different religious communities living in Lebanon. While evolving primarily within Lebanon, these communities show a level of local isolation as demonstrated previously from their Y-haplogroup distributions. In order to trace the origins and migratory patterns that may have led to the genetic isolation and autosomal clustering in some of these communities we analyzed Y-chromosome STR and SNP sample data from 6327 individuals, in addition to whole genome autosomal sample data from 609 individuals, from Mount Lebanon and other surrounding communities. We observed Y chromosome L1b Levantine STR branching that occurred around 5000 years ago. Autosomal DNA analyses suggest that the North Lebanese Mountain Maronite community possesses an ancestral Fertile Crescent genetic component distinct from other populations in the region. We suggest that the Levantine L1b group split from the Caucasus ancestral group around 7300 years ago and migrated to the Levant. This event was distinct from the earlier expansions from the Caucasus region that contributed to the wider Levantine populations. Differential cultural adaption by populations from the North Lebanese Mountains are clearly aligned with the L1b haplotype STR haplogroup clusters, indicating pre-existing and persistent cultural barriers marked by the transmission of L1b lineages. Our findings highlight the value of uniparental haplogroups and STR haplotype data for elucidating biosocial events among these populations.Subject terms: Population genetics, Computational biology and bioinformatics  相似文献   
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10.

Background and aims

Lynch syndrome (LS) is associated with an increased risk of small bowel tumors but routine screening is not recommended in international guidelines. The aim of our study was to determinate the prevalence of duodenal tumors in a French cohort of LS patients.

Methods

Patients carrying a germline pathogenic variant in a MMR gene, supported by our local network, in which at least one upper endoscopy had been performed, were included. We registered the occurrence of duodenal lesions in those patients.

Results

154 LS patients were identified including respectively 85 MSH2 and 41 MLH1 mutated patients respectively. Seven out of 154 (4.5%) had at least one duodenal lesion. Median age at diagnosis was 58 years (range: 49–73). The twelve lesions locations were: descending duodenum (n?=?7), genu inferius (n?=?2), duodenal bulb (n?=?1), ampulla (n?=?1), fourth duodenum (n?=?1). Three lesions were invasive adenocarcinomas. The incidence rate of duodenal lesions in patients with MSH2 or MLH1 pathogenic variants was respectively 7.1% (6 out of 85) and 2.4% (1 out of 41) emphasizing a trend toward increased risk of developing duodenal lesion in MSH2 mutated patients: OR: 5.17, IC95% (0.8–60.07), p?=?0.1307.

Conclusion

Regarding this high prevalence rate, especially in MSH2 patients, regular duodenal screening during upper endoscopy should be considered in routine in LS patients.  相似文献   
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