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121.
The complexation with beta-cyclodextrin (beta-CD) has been investigated using reversed-phase liquid chromatography. The compounds tested have been pindolol and, for comparison purposes, indole and 4-methoxyindole. The retention behaviour has been analysed on a Kromasil 100 C18 column and the mobile phase used was methanol-pH 6 phosphate buffer (15/85v/v) in which beta-CD was incorporated as a mobile phase additive. The decrease in the retention times with increasing concentrations of beta-CD enables the determination of the apparent stability constants of the complexes. In addition, the low solubility of pindolol, a weak base, in pH 12 aqueous solution has been improved by complexation with different cyclodextrins. The solubility enhancements with 1.4 x 10(-2) M beta-, hydroxypropyl-beta, and gamma-CD have been 1.9, 1.8 and 1.4-fold, respectively, with 2.4 x 10(-2) M methyl-beta-CD it was 2.8-fold whilst no effect was observed with alpha-CD. The stability constants of the complexes at pH 12 have been determined from the solubility isotherms.  相似文献   
122.
Abstract The factors associated with overall mortality and liver decompensation in HIV and hepatitis C virus (HCV)-coinfected patients who are evaluated to receive HCV antiviral therapy with a known liver histological fibrosis stage were evaluated in a prospective cohort study. A total of 387 consecutive HIV/HCV-coinfected patients attending an outpatient clinical unit between January 1997 and December 2007 who fulfilled criteria to be treated with interferon and to whom liver biopsy was performed were included and followed every 6 months from time of liver biopsy to death or to December 2008. The follow-up period was 6.2 years (IQR: 3.5-9.2). The median age at time of liver biopsy was 38 years. This included 73% men; 28% had advanced liver fibrosis (F3-F4) and a CD4 cell count of 556 cells/mm(3), 72% had HIV RNA <400 copies/ml and a mean CD4 nadir of 207 cell/mm(3), 21% had a previous diagnosis of AIDS, and 92% were on antiretroviral therapy. During follow-up 48% underwent HCV antiviral therapy, with a sustained virological response in 33%. The overall mortality rate and the incidence of liver decompensation or liver-related death were 1.17 and 0.72 per 100 patients-year, respectively. End stage liver disease (9/28 patients) and non-AIDS-related cancer (6/28) were the main causes of death. F3-F4 (HR: 3.74, 95% CI: 1.69-8.26, p=0.001) and previous AIDS diagnosis (HR: 3.04, 95% CI: 1.36-6.81) were the factors independently associated with death. Mortality rates in patients who received and who did not receive HCV antiviral therapy were 0.44 and 2.04 per 100 patients-year, respectively (p=0.003). In addition to the low mortality rate observed, HIV/HCV-coinfected patients with poor predictors of survival are candidates for intensive clinical management.  相似文献   
123.
Evidence from a range of sources demonstrates that end-of-life (EoL) care practices and preferences vary across countries; culture is consistently one of the main explanations given for this. In order to understand how cultural factors are used to explain similarities and differences in EoL care between Spain, Italy and Portugal, database and hand searches were performed and cross-cutting core themes identified. Similarities included higher proportions of people who wished to die at home than actually died at home, a persistent trend for partial disclosure in Italy and Spain, low use of advance directives, and low incidence of all medical EoL decisions (with the exception of terminal sedation) compared to northern European countries. The role of religion and the importance of family ties were the two main cultural factors used to explain the similarities. Further research is needed in order to interpret the important differences that were also found.  相似文献   
124.
Myc (c-Myc) counteracts p27 effects, and low p27 usually correlates with high Myc expression in human cancer. However there is no information on the co-expression of both genes in chronic lymphocytic leukemia (CLL). We found a lack of correlation between RNA and protein levels of p27 and Myc in CLL cells, so we determined the protein levels by immunoblot in 107 cases of CLL. We observed a high p27 protein expression in CLL compared to normal B cells. Ectopic p27 expression in a CLL-derived cell line resulted in cell death resistance. Surprisingly, Myc expression was very low or undetectable in most CLL cases analyzed, with a clear correlation between high p27 and low Myc protein levels. This was associated with low Skp2 expression, which is consistent with the Skp2 role in p27 degradation and with SKP2 being a Myc target gene. High Myc expression did not correlate with leukemia progression, despite that cell cycle-related Myc target genes were upregulated. However, biochemical analysis showed that the high p27 levels inhibited cyclin-Cdk complexes even in Myc expressing CLL cells. Our data suggest that the combination of high p27 and low Myc is a marker of CLL cells which is mediated by Skp2.  相似文献   
125.
ContextPatients from minority ethnic groups experience lower rates of referrals to end-of-life (EoL) care services, higher levels of dissatisfaction with services, and perceive some services as culturally inappropriate.ObjectivesTo systematically review original studies of minority ethnic groups and EoL care in the U.K. and appraise their quality.MethodsSearches were carried out in 13 electronic databases, eight journals, reference lists, and the gray literature. Studies of minority ethnic groups and EoL care in the U.K. were included. Studies were graded for quality and key themes were identified.ResultsForty-five studies met inclusion criteria. Study quality was good on average. Identified key themes included age structure; inequality by disease group; referrals; caregivers; place of care and death; awareness of services and communication; and cultural competency. Strategies described for the reduction of inequities were partial and reactive. The format of 10 studies prevented quality grading; these were, however, reviewed as they provided unique insights. Variations in terminology and sampling frames complicated comparison across studies.ConclusionThe results highlight the multiple and related factors that contribute to low service use and substandard quality of services experienced by minority ethnic groups, and the need for authors to clarify what they mean by “culturally competent” EoL care. The synthesis of diverse and disparate studies underpins a number of key recommendations for health care professionals and policymakers. Tackling these epidemiological, demographic, institutional, social, and cultural factors will require a systematic and organization-wide approach rather than the current piecemeal and reactive interventions.  相似文献   
126.
CD137 artificial costimulation results in complete tumor rejection in several mouse models. Type I interferons (IFN) exert antitumor effects through an array of molecular functions on malignant cells, tumor stroma and immune system cells. The fact that agonist anti‐CD137 mAb induce tumor regressions in mice deficient in the unique receptor for Type I IFNs (IFNAR?/?) indicated potential for treatment combinations. Indeed, combination of intratumor injections of mouse IFN‐α and intraperitoneal injections of anti‐CD137 mAb synergized as seen on subcutaneous lesions derived from the MC38 colon carcinoma, which is resistant to each treatment if given separately. Therapeutic activity was achieved both against lesions directly injected with IFN‐α and against distant concomitant tumors. Experiments in bone marrow chimeras prepared with IFNAR?/? and WT mice concluded that expression of the receptor for Type I interferons is mainly required on cells of the hematopoietic compartment. Synergistic effects correlated with a remarkable cellular hyperplasia of the tumor draining lymph nodes (TDLNs). Enlarged TDLNs contained more plasmacytoid and conventional dendritic cells (DC) that more readily cross‐presented. Importantly, numbers of both DC subtypes inversely correlated with the tumor size. Numbers of CD8 T cells specific for a dominant tumor antigen were increased at TDLNs by each separate treatment but only with slight augments due to the combination. Combined antitumor effects of the therapeutic strategy were also seen on subcutaneous TC‐1 tumors established for 24 days before treatment onset. The described strategy is realistic because (i) agents of each kind are clinically available and (ii) equivalent procedures in humans are feasible.  相似文献   
127.

Background

PIK3CA mutations in the helical domain (in exon 9) and in the kinase domain (exon 20) cause tumor formation by different means. We aimed to determine the effects of each of these mutations on survival of colon carcinoma patients.

Methods

A large cohort of 685 colon carcinoma patients was tested for PIK3CA mutations in exons 9 and 20 by single nucleotide primer extension (N?=?428) or by real time PCR (N?=?257).

Results

PIK3CA mutation rate was 13%. 66 of 83 (79.5%) were in exon 9 and 17 of 83 (20.5%) in exon 20. In survival analysis, PIK3CA mutations in exon 9 and 20 had different effects on patient outcome. The PIK3CA exon 20 mutation conferred a poorer disease free survival compared to patients with wild type alleles and exon 9 mutations (Log rank p?=?0.04 and p?=?0.03 respectively) and cancer specific survival (Log rank p?=?0.03 and p?=?0.056 respectively) in stage III patients. In stage I and II this negative effect on outcome was not seen.

Conclusions

PIK3CA mutation in exon 20 is a negative prognostic factor in stage III colon cancer patients. Moreover, this negative effect is not present in stage I and II patients.  相似文献   
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