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21.
This article discusses challenges of language differences in qualitative research, when participants and the main researcher have the same non-English native language and the non-English data lead to an English publication. Challenges of translation are discussed from the perspective that interpretation of meaning is the core of qualitative research. As translation is also an interpretive act, meaning may get lost in the translation process. Recommendations are suggested, aiming to contribute to the best possible representation and understanding of the interpreted experiences of the participants and thereby to the validity of qualitative research.  相似文献   
22.
Proteasomal proteolysis relies on the activity of six catalytically active proteasomal subunits (beta1, beta2, beta5, beta1i, beta2i and beta5i). Applying a functional proteomics approach, we used a recently developed activity-based, cell-permeable proteasome-specific probe that for the first time allows differential visualization of individual active proteasomal subunits in intact primary cells. In primary leukemia samples, we observed remarkable variability in the amounts of active beta1/1i-, beta2/2i- and beta5/5i-type of subunits, contrasting with their constant protein expression. Bortezomib inhibited beta5- and beta1-type, but to a lesser extend beta2-type of subunits in live primary cells in vitro and in vivo. When we adapted the bortezomib-sensitive human acute myeloid leukemia cell line HL-60 to bortezomib 40 nM (HL-60a), proteasomal activity profiling revealed an upregulation of active subunits, and residual beta1/beta5-type of activity could be visualized in the presence of bortezomib 20 nM, in contrast to control cells. In a panel of cell lines from hematologic malignancies, the ratio between beta2-type and (beta1 + beta5)-type of active proteasomal polypeptides mirrored different degrees of bortezomib sensitivity. We thus conclude that the proteasomal activity profile varies in primary leukemia cells, and that the pattern of proteasomal subunit activity influences the sensitivity of hematologic malignancies toward bortezomib.  相似文献   
23.
To obtain insight into the mechanism(s) of posttransplantation humoral immunodeficiency, we evaluated factors affecting serum antibody levels against polio, tetanus, Haemophilus influenzae, and Streptococcus pneumoniae in 87 patients. Patients with hematologic malignancies were randomized to receive marrow versus blood stem cells, which contain approximately 10 times more lymphocytes than marrow. Blood stem cell recipients did not have higher antibody levels than marrow recipients. Recipient pretransplantation antibody levels were correlated with the posttransplantation levels, especially in the first 6 months after transplantation when the correlation coefficients typically exceeded 0.6. Donor pretransplantation antibody levels had less of a correlation with posttransplantation levels in the recipient. Patient or donor age, total body irradiation, and graft-versus-host disease or its treatment appeared to have no effect. In conclusion, antibody levels in the first year after transplantation are affected primarily by pretransplantation antibody levels in the recipient and, to a lesser degree, in the donor. These findings suggest that immunization of the recipient and the donor before transplantation may be more effective in improving antibody immunity after transplantation than manipulating graft-versus-host disease, changing conditioning, or increasing the number of lymphocytes in the graft.  相似文献   
24.
Patients with a history of sporadic adenomas have increased epithelial cell proliferative activity, an intermediate risk marker for colorectal cancer. Reduction of proliferation by dietary intervention may reflect a decreased colorectal cancer risk. To evaluate whether calcium or resistant starch could reduce proliferative activity throughout the colon, we performed a randomized controlled trial in 111 sporadic adenoma patients. Patients received two placebos, 1 g of calcium + placebo, or 30 g of amylomaize (19 g of resistant starch) + placebo. After 2 mo, biopsies were collected from the cecum, transverse and sigmoid colon, and rectum during colonoscopy. Epithelial cell proliferation was determined by dividing the number of 5-bromo-2-deoxyuridine-labeled nuclei by the total number of nuclei x 100 (labeling index, LI). LI of luminal, mid, and basal compartments was determined. Twenty-five patients dropped out. In the remaining 86 patients (28 treated with placebo, 30 with calcium + placebo, and 28 with resistant starch + placebo), no difference was observed in total LI, the LI of the three compartments, or the crypt length in the four areas of the colorectum. Colonic epithelial cell proliferative activity throughout the colon of sporadic adenoma patients is not affected by supplementation with 1 g of calcium or 19 g of resistant starch.  相似文献   
25.
We examined whether gender differences in health, psychological well-being, and life satisfaction, can be explained by effects of work-related and nonwork-related sources of social support. The sample consisted of 459 men and women from dual earner families. Men report better health and psychological well-being than women, whereas women report higher life satisfaction than men. Contrary to our expectations, women receive more social support from colleagues than men, while men and women equally receive support from their supervisor. As for the nonwork-related sources of social support, men receive more social support from their spouse, while women receive more social support from relatives and friends. No gender differences exist in the effects of social support. Although men and women differ with respect to the social support they receive from different sources, these differences cannot explain gender differences in health, psychological well-being and life satisfaction.  相似文献   
26.
Responsive evaluation offers a perspective in which evaluation is reframed from the assessment of program interventions on the basis of policymakers' goals to an engagement with all stakeholders about the value and meaning of their practice. This article argues for this perspective both generally and more particularly in relation to health promotion. Responsive evaluation is especially appropriate in health promotion contexts characterized by a high degree of ambiguity. Ambiguity refers to the absence of or contradictory interpretations about what needs to, can and should be done, when and where. Ambiguity is high in the case of non-routine programs, lack of knowledge about success indicators, collaborative and community based programs and the absence of consensus among stakeholders. In health promotion contexts marked by a low degree of ambiguity random controlled trials (RCTs) and quantitative methods are to be considered. This implies the evaluators should assess the degree of ambiguity of a situation before deciding about an appropriate design.  相似文献   
27.
28.
Recently we identified a new variant, S845G, in the MLH3 gene in 7 out of 327 patients suspected of hereditary nonpolyposis colorectal cancer but not fulfilling the Amsterdam criteria and in 1 out of 188 control subjects. As this variant might play a role in causing sporadic colorectal cancer, we analyzed its prevalence in sporadic colorectal cancer patients. We analyzed a small part of exon 1 of the MLH3 gene, including the S845G variant, in germline DNA of 467 white sporadic colorectal cancer patients and 497 white controls. The S845G variant was detected in five patients and eight controls; the results thus indicate that this variant does not confer an increased colorectal cancer risk. Another variant (P844L) was clearly a polymorphism. Three other missense variants were rare and the sample size of the study was too small to conclude whether they are pathogenic. In conclusion, no association was observed between two MLH3 variants (P844L and S845G) and colorectal cancer risk.  相似文献   
29.
Detection of visual change: mismatch or rareness?   总被引:1,自引:0,他引:1  
Kenemans JL  Jong TG  Verbaten MN 《Neuroreport》2003,14(9):1239-1242
How do we detect changes in our visual environment? By continuously comparing visual inputs to templates of experiences in the immediate past? Or by determining their rareness, how infrequently a visual event occurred previously? Recent results from event-related potentials have been interpreted in favour of the first hypothesis, as in the case of the auditory mismatch negativity. Here we demonstrate that rareness, rather than mismatch with a template, underlies visual change detection. Such rareness is detected through a dedicated mechanism in human visual cortex about 100 ms after the rare event occurs, reflected in the rareness-related negativity (RRN).  相似文献   
30.
We examined the content validity of the Pediatric Quality of Life Inventory? Young Child Self-report (PedsQL?-YC) in children with autism spectrum disorder (ASD) and intellectual disability and made recommendations for the development of a quality of life (QOL) measure. Ten children, 14 parents, and three teachers were recruited for focus groups and interviews. Focus groups and interviews were conducted to obtain their perceptions about the appropriateness of the PedsQLTM-YC (Phase 1). Based on the results from Phase 1, recommendations for a QOL measure for children with ASD and intellectual disability were made (Phase 2). After piloting a QOL measure by children and subsequent interviews, further refinement was undertaken (Phase 3). Data from Phases 1 and 3 were analysed using thematic and content analyses. Findings suggest that a QOL measure for children with ASD and intellectual disability should be related specifically to the children’s daily life and contexts. Due to the specific cognitive and behavioural characteristics of this population, the wording, response options and presentation style of the existing PedsQL?-YC would need refinement. Questions about social interactions with friends appeared less relevant to children with ASD. These recommendations address the wording and formatting issues needed for a QOL measure for use in children with ASD and intellectual disability identified through qualitative research methods. Further research is needed to include additional or modified questions in the social domain.  相似文献   
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