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101.
In this study, we observed the occurrence of TRBV8.1-DB2.1 V(D)J recombination in murine fetal thymus organ culture (FTOC), in which the thymic microenvironment is mimicked. Since ionizing radiation affects T-cell development, we irradiated FTOCs with gamma rays to evaluate the modulation of genes implicated in TRBV8.1-BD2.1 rearrangements. The nylon cDNA microarray method was employed to monitor the expression of 9216 genes, which were organized in coexpression clusters. Clustering analysis showed similar expression profiling of genes implicated in the V(D)J recombination and DNA double strand break (DSB) repair processes such as XRCC4, RAG-2, Artemis and DNA-PK-cs, thus suggesting overlap between the two processes. The RUNX3 gene, whose coded protein binds to the enhancers of TR genes, was also modulated and the DNA cross-linking LR1 gene, which plays a role in the opening of hairpin DNA structures and whose expression pattern is similar to Artemis, may play a role in the control of V(D)J recombination. Furthermore, our data demonstrate that the FTOC model system and cDNA microarray method are useful tools to evidentiate genes that may play a role in both processes V(D)J recombination and DNA repair.  相似文献   
102.

Background

TAVI is an alternative solution for patients with aortic valve stenosis (AS) who are refused for conventional surgery. We sought to evaluate the incidence, characteristics, predictors and prognosis impact of serious hemorrhagic complications following transcatheter aortic valve implantation (TAVI).

Methods

One hundred and seventy one consecutive patients with symptomatic severe AS (83.5 ± 6.1 y; 53% women; mean EuroSCORE = 22.1 ± 12.3) underwent transapical (TA) or transfemoral (TF) TAVI in our institution using Edwards SAPIEN© and Medtronic CoreValve© devices. The primary evaluated criterion was the incidence of any bleeding complication, according to the Valve Academic Research Consortium (VARC) criteria.

Results

VARC serious hemorrhagic complications occurred in 34.5% of patients (n = 23 life-threatening/disabling (LT/D) and n = 36 major bleedings). Most of these complications were related to access site complications (69%). Multivariable analysis revealed that TA access, low weight and underlying coronary artery diseases were independent predictors for development of serious bleeding. The mortality was significantly higher in patients with serious events compared to patients without bleeding (p = 0.008, log-rank analysis). Although the survival didn't significantly differ in patients with major hemorrhagic events, subjects with LT/D bleeding events had a higher mortality than the subjects with no hemorrhagic complications (p < 0.001, log-rank analysis). Occurrence of VARC LT/D event independently predicted all-cause mortality (HR = 5.35 [2.51–11.43], p < 0.001) during the first year following TAVI in multivariate Cox regression analysis.

Conclusion

Severe bleeding is frequent following TAVI procedure and is mainly related to local hemorrhage. VARC LT/D events are associated with decreased survival after AS correction.  相似文献   
103.
104.
Neonatal ventral hippocampal (nVH) lesions in rats have been widely used as a neurodevelopmental model that mimics schizophrenia-like behaviors. Recently, we reported that nVH-lesions result in significant decreases in both length of dendrites and dendritic density of spines of pyramidal neurons of the prefrontal cortex (PFC) and in the density of dendritic spines of medium spiny neurons of the nucleus accumbens (NAcc). Moreover, postweaning social isolation induces major decreases in dendritic spiny density of PFC neurons. We investigated here the comparative dendritic morphology of PFC pyramidal neurons and NAcc medium spiny neurons in nVH rats, following social isolation after weaning (8 weeks). Morphological characteristics of dendrites were measured using the Golgi-Cox procedure followed by a Sholl analysis. Social isolation (SI) by itself induced decreases in dendritic length and dendritic spine density of the NAcc. In socially isolated nVH-lesion rats decrease in dendritic length in PFC and NAcc neurons were exacerbated whereas an increase in spine density of medium spiny neurons was observed in the NAcc. These results indicate that nVH-lesions alter dendritic morphology of NAcc and PFC neurons. These anatomical modifications in both structures may be relevant to behaviors observed in schizophrenia.  相似文献   
105.
Aspergillus fumigatus is a model fungal pathogen and a common cause of infection in individuals with the primary immunodeficiency chronic granulomatous disease (CGD). Although primarily considered a deficiency of innate immunity, CGD is also linked to dysfunctional T cell reactivity. Both CD4(+) and CD8(+) T cells mediate vaccine-induced protection from experimental aspergillosis, but the molecular mechanisms leading to the generation of protective immunity and whether these mechanisms are dysregulated in individuals with CGD have not been determined. Here, we show that activation of either T cell subset in a mouse model of CGD is contingent upon the nature of the fungal vaccine, the involvement of distinct innate receptor signaling pathways, and the mode of antigen routing and presentation in DCs. Aspergillus conidia activated CD8(+) T cells upon sorting to the Rab14(+) endosomal compartment required for alternative MHC class I presentation. Cross-priming of CD8(+) T cells failed to occur in mice with CGD due to defective DC endosomal alkalinization and autophagy. However, long-lasting antifungal protection and disease control were successfully achieved upon vaccination with purified fungal antigens that activated CD4(+) T cells through the endosome/lysosome pathway. Our study thus indicates that distinct intracellular pathways are exploited for the priming of CD4(+) and CD8(+) T cells to A. fumigatus and suggests that CD4(+) T cell vaccination may be able to overcome defective antifungal CD8(+) T cell memory in individuals with CGD.  相似文献   
106.

Purpose

The aim of this study was to evaluate the ability of prenatal ultrasound markers to predict postnatal renal prognosis in fetuses with posterior urethral valves.

Methods

Medical files on fetuses with prenatal diagnosis of posterior urethral valves from 2000 to 2006 were reviewed retrospectively. Data from prenatal follow-up included gestational age at diagnosis, ultrasound renal parenchyma evaluation, and presence and time of oligohydramnios onset. Prenatal parameters studied were correlated to postnatal renal function.

Results

Thirty-one male fetuses were included. Six pregnancies were terminated. Of the remaining 25 pregnancies that were continued, 4 children had abnormal creatine and 21 normal creatinine levels at follow-up. Presence and time of oligohydramnios onset did not differ between groups (P = .43). Ultrasound detected bilateral renal abnormalities in 3 fetuses (75%) with altered renal function, and 10 fetuses (55%) with normal creatinine, at follow-up.

Conclusions

None of the ultrasound parameters evaluated were able to reliably predict postnatal renal function.  相似文献   
107.
Endometrial carcinoma (EC) molecular classification based on four molecular subclasses identified in The Cancer Genome Atlas (TCGA) has gained relevance in recent years due to its prognostic utility and potential to predict benefit from adjuvant treatment. While most ECs can be classified based on a single classifier (POLE exonuclease domain mutations – POLEmut, MMR deficiency – MMRd, p53 abnormal – p53abn), a small but clinically relevant group of tumours harbour more than one molecular classifying feature and are referred to as ‘multiple-classifier’ ECs. We aimed to describe the clinicopathological and molecular features of multiple-classifier ECs with abnormal p53 (p53abn). Within a cohort of 3518 molecularly profiled ECs, 107 (3%) tumours displayed p53abn in addition to another classifier(s), including 64 with MMRd (MMRd–p53abn), 31 with POLEmut (POLEmut–p53abn), and 12 with all three aberrations (MMRd–POLEmut–p53abn). MMRd–p53abn ECs and POLEmut–p53abn ECs were mostly grade 3 endometrioid ECs, early stage, and frequently showed morphological features characteristic of MMRd or POLEmut ECs. 18/28 (60%) MMRd–p53abn ECs and 7/15 (46.7%) POLEmut–p53abn ECs showed subclonal p53 overexpression, suggesting that TP53 mutation was a secondary event acquired during tumour progression. Hierarchical clustering of TCGA ECs by single nucleotide variant (SNV) type and somatic copy number alterations (SCNAs) revealed that MMRd–p53abn tumours mostly clustered with single-classifier MMRd tumours (20/23) rather than single-classifier p53abn tumours (3/23), while POLEmut–p53abn tumours mostly clustered with single-classifier POLEmut tumours (12/13) and seldom with single-classifier p53abn tumours (1/13) (both p ≤ 0.001, chi-squared test). Finally, the clinical outcome of patients with MMRd–p53abn and POLEmut–p53abn ECs [stage I 5-year recurrence-free survival (RFS) of 92.2% and 94.1%, respectively] was significantly different from single-classifier p53abn EC (stage I RFS 70.8%, p = 0.024 and p = 0.050, respectively). Our results support the classification of MMRd–p53abn EC as MMRd and POLEmut–p53abn EC as POLEmut. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
108.
Steroid joint injections may be effective in painful joints due to degenerative disease and posttraumatic changes, as well as rheumatoid arthritis and seronegative spondylarthropathy. Fluoroscopic guidance may be necessary for deep (sacroiliac, hip, and shoulder) or small (wrist, hand, and foot) joints. Detailed technique of the steroid injection is given, especially for the sacroiliac joint.  相似文献   
109.
Techniques of percutaneous synovial biopsy under fluoroscopic control of large joints of the limbs (other than the knee) may be useful in arthritis of undetermined etiology especially when infection is considered. Main technical refinements include adequate selection of an optimal approach and biopsy site using new imaging methods, use of a Tru-Cut(R) needle, and placement of the cutting window tangential to the joint surface, and selection of an optimal approach and biopsy site. Detailed technique of the synovial biopsy of hip, ankle, shoulder, and elbow joints is discussed.  相似文献   
110.
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