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101.
102.

Background

Febrile urinary tract infections (fUTIs) are common after kidney transplantation (KTx); however, prospective data in a multicenter pediatric cohort are lacking. We designed a prospective registry to record data on fUTI before and after pediatric KTx.

Methods

Ninety-eight children (58 boys and 40 girls)?≤?18 years from 14 mid-European centers received a kidney transplant and completed a 2-year follow-up.

Results

Posttransplant, 38.7 % of patients had at least one fUTI compared with 21.4 % before KTx (p?=?0.002). Before KTx, fUTI was more frequent in patients with congenital anomalies of kidneys and urinary tract (CAKUT) vs. patients without (38 % vs. 12 %; p?=?0.005). After KTx, fUTI were equally frequent in both groups (48.7 % vs. 32.2 %; p?=?0.14). First fUTI posttransplant occurred earlier in boys compared with girls: median range 4 vs. 13.5 years (p?=?0.002). Graft function worsened (p?<?0.001) during fUTI, but no difference was recorded after 2 years. At least one recurrence of fUTI was encountered in 58 %.

Conclusion

This prospective study confirms a high incidence of fUTI after pediatric KTx, which is not restricted to patients with CAKUT; fUTIs have a negative impact on graft function during the infectious episode but not on 2-year graft outcome.
  相似文献   
103.

Purpose

Oncological surgery in immunosuppressed patients with solid organ transplantation (Tx) is challenging. These patients are thought to have higher postoperative morbidity and an increased rate of tumour progression. The aim of the present study was to analyse oncological, functional and perioperative outcomes in Tx patients following radical prostatectomy (RP).

Materials and methods

Between 1996 and 2014, 30 patients diagnosed with prostate cancer underwent RP at our institution following Tx (kidney: n = 20, heart: n = 5, liver: n = 5). Functional, oncological and perioperative follow-ups were analysed. Postoperative complications were assessed using the Clavien–Dindo classification.

Results

Median follow-up was 45 months. Median PSA was 5.3 ng/ml. Intraoperative blood loss was 600 ml at a median operating time of 180 min. Surgery in kidney Tx patients was technically feasible. Major complications occurred in 3 patients (ureteral injury, lymphocele and haematoma). Histological evaluation revealed n = 18 ≤pT2 tumours (60.0 %), n = 7 pT3a tumours (23.3 %) and n = 5 ≥pT3b tumours (16.7 %). Continence rate 12 months after surgery, defined as no or one safety pad use, was 73.3 %, while 93.3 % of the patients used ≤2 pads/24 h. After the median follow-up of 45 months, BCR-free survival was 69.0 %. In recurrent men, there was suspicion of metastasis in one patient. No cancer-specific death was observed. Five-year overall survival was 94.4 %.

Conclusion

The complication rate in patients with solid organ transplantation after RP was low. While histopathological evaluation revealed disease characteristics comparable to non-transplant patients from current RP series, postoperative continence was worse. Immunosuppressive therapy does not seem to lead to an increased rate of tumour progression.
  相似文献   
104.
105.
Howard KE  Burkhard MJ 《Immunology》2007,122(4):571-583
The majority of human immunodeficiency virus type 1 (HIV-1) infections occur via mucosal transmission through contact with genital secretions containing cell-associated and cell-free virus. However, few studies have assessed whether exposure to cells, HIV-1 infected or uninfected, plays a role in the sexual transmission of HIV-1. This study examined phenotypic changes in mucosal and systemic lymphoid tissue 24 hr after vaginal exposure to in vitro equilibrated infectious doses of cell-associated or cell-free feline immunodeficiency virus, uninfected heterologous cells, or medium alone. We found that even at this early time-point, mucosal exposure to virus induced substantial alterations in the phenotype and distribution of leucocytes, particularly in the tissues of the mucosal immune system. Second, we found that the type of virus inoculum directly influenced the phenotypic changes seen. Vaginal exposure to cell-free virus tended to induce more generalized phenotypic changes, typically in the peripheral immune system (blood and systemic lymph nodes). In contrast, exposure to cell-associated virus was primarily associated with phenotypic shifts in the mucosal immune system (gut and mucosal/draining lymph nodes). In addition, we found that exposure to uninfected heterologous cells also induced alterations in the mucosal immune system. These data suggest that significant immune changes occur within the first 24 hr of virus exposure, well before substantial replication would be anticipated. As the mucosal immune system, and particularly the gut, is an early and persistent target for lentiviral replication, these findings have substantial implications for HIV-1 pathogenesis and vaccine development.  相似文献   
106.
The development of MHC/peptide multimers has facilitated the visualization and purification of antigen-specific T cells. However, the persistence of multimers leads to prolonged T cell receptor signaling and subsequently to altered T-cell function. We have recently developed a new type of MHC/peptide multimers, which can be dissociated from the T cell. Herein, we have generated and tested for the first time reversible HLA/peptide multimers, termed Streptamers, for the isolation of human T cells. The Streptamer technique demonstrates the specificity and sensitivity of conventional HLA/peptide tetramers with regards to the sorting of human T lymphocytes. This is shown for T cells directed against immunogenic peptides derived from viral and tumor-associated antigens. We show that antigen-specific cytotoxic T cells remain functionally active following Streptamer dissociation, whereas lytic function and proliferation of the T cells is impaired in the presence of conventional tetramers. These novel HLA/peptide Streptamer reagents allow the isolation of antigen-specific T cells with preserved function and, therefore, facilitate the development of adoptive T cell transfer regimens for the treatment of patients with cancer or infectious diseases.  相似文献   
107.
BACKGROUND: Hyperthymic Temperament (HYT) and a closely related trait, Hypomanic Personality (HYP), have both been related to bipolar affective disorder (BAD). Intensity dependence of auditory evoked potentials (IAEP) is a suggested inverse indicator of serotonergic neurotransmission and has been found to be elevated in BAD. Therefore the present study explored for the first time whether subclinical variance of HYT/HYP is also associated with IAEP in a healthy sample. As several traits from biological personality research are correlated with HYT/HYP and also with BAD, the specificity of results against these traits was further analyzed by calculating multiple regression analyses. METHODS: Evoked potentials were recorded from a sample (N=87) homogenous for confounding variables influencing IAEP. For this reason, only 19 to 27-year-old non-smoker psychiatrically healthy male students were included. RESULTS: Significant correlations were found between IAEP and both HYP and HYT. Including Sensation or Novelty Seeking and Extraversion in Regression Analyses did not weaken the associations of HYP with IAEP much, but did affect those of HYT. However, these competing biological personality traits were hardly able to predict IAEP themselves. Impulsivity, though, was able to reduce the predictive power of HYP and HYT and to explain unique IAEP-variance. This was even more the case for Behavioral-Activation-System-Sensitivity (BAS) subscale Fun Seeking clearly dominating all regression analyses. LIMITATIONS: Homogeneity of sample. CONCLUSIONS: The impact of BAS is in agreement with the assumption that heightened BAS-sensitivity is an underlying biological cause for HYP/HYT and for BAD. Future studies on BAD should include BAS and Impulsivity besides HYP/HYT to further explore uniqueness of the latter and to develop questionnaires based on those items of a hyperthymic-hypomanic-impulsive-funseeking item pool, which possess the most external validity.  相似文献   
108.
109.
Confirmation or exclusion of recent heroin consumption is still one of the major challenges for forensic and clinical toxicologists. A great variety of biomarkers is available for heroin abuse confirmation, including various opium alkaloids (eg, morphine, codeine), street heroin impurities (eg, 6‐acetylcodeine [6‐AC], noscapine, papaverine) as well as associated metabolites (eg, 6‐monoacetylmorphine [6‐MAM], morphine glucuronides). However, the presence of most of these biomarkers cannot solely be attributed to a previous heroin administration but can, among other things, also be due to consumption of poppy seed products (‘poppy seed defense’), opium preparations or specific medications, respectively. A reliable allocation is of great importance in different contexts, for instance in the case of DUID (driving under the influence of drugs) investigations, in driving licence re‐granting processes, in workplace drug testing (WDT), as well as in post‐mortem identification of illicit opiate use. Additionally, differentiation between illicit street heroin abuse and pharmaceutical heroin administration is also important, especially within the frame of heroin‐assisted treatments. Therefore, analysis of multiple biomarkers is recommended when illicit opiate consumption is assumed to obtain the most reliable results possible. Beyond that, interpretation of positive opiate test results requires a profound insight into the great variety of biomarkers available and their validity regarding the alleged consumption. This paper aims to provide an overview of the wide variety of heroin abuse biomarkers described in the literature and to review them regarding their utility and reliability in daily routine analysis.  相似文献   
110.
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