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991.
Between July and December 1993, the Hopi Department of Health Services, in collaboration with the Arizona Cancer Center (AZCC), conducted a population-based study of cervical cancer risk factors, screening practices, and predictors of Pap test utilization among American Indian women age 18 years and older living on the Hopi reservation in northern Arizona. This survey, entitled the Healthy Hopi Women's Study, involved a stratified random sample of households from each of the 11 Hopi villages. The final study sample was 559 completed face-to-face interviews. This article reports on unpublished findings of the survey and discusses how the Hopi utilized the study's findings to develop a Centers for Disease Control and Prevention (CDC)-funded breast and cervical cancer program.  相似文献   
992.
PIK3CA, encoding the p110alpha catalytic subunit of phosphatidylinositol 3-kinase (PI3K), is mutated in a variety of human cancers. We screened the colon cancer cell lines previously established in our laboratory for PIK3CA mutations and found that four of them harbored gain of function mutations. We have now compared a panel of mutant and wild-type cell lines for cell proliferation and survival in response to stress. There was little difference in PI3K activity between mutant PIK3CA-bearing cells (mutant cells) and wild-type PIK3CA-bearing cells (wild-type cells) under optimal growth conditions. However, the mutant cells showed constitutive PI3K activity during growth factor deprivation stress (GFDS), whereas PI3K activity decayed rapidly in the wild-type cells. Importantly, constitutively active PI3K rendered the mutant cells resistant to GFDS-induced apoptosis relative to the wild-type cells, indicating a biological advantage under stress conditions that is imparted by the mutant enzymes. Compared with the wild-type cells, the mutant cells were hypersensitive to the apoptosis induced by the PI3K inhibitor LY294002. In addition, PIK3CA small interfering RNA significantly decreased DNA synthesis and/or induced apoptosis in the mutant cells but not in the wild-type cells. Furthermore, ecotopic expression of a mutant PIK3CA in a nontumorigenic PIK3CA wild-type cell line resulted in resistance to GFDS-induced apoptosis, whereas transfection of wild-type PIK3CA or empty vector had little effect. Taken together, our studies show that mutant PIK3CA increases the capacity for proliferation and survival under environmental stresses, such as GFDS while also imparting greater dependency on the PI3K pathway for proliferation and survival.  相似文献   
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994.

Background

Evidence-based, single-session STI/HIV interventions to reduce sexual risk taking are potentially effective options for implementation in resource-limited settings and may solve problems associated with poor participant retention.

Purpose

The purpose of the study is to estimate the efficacy of single-session, behavioral interventions in reducing unprotected sex or increasing condom use.

Methods

Data sources were searched through April 2013 producing 67 single-session interventions (52 unique reports; N?=?20,039) that included outcomes on condom use and/or unprotected sex.

Results

Overall, participants in single-session interventions reduced sexual risk taking relative to control groups (d + ?=?0.19, 95 % CI?=?0.11, 0.27). Within-group effects of the interventions were larger than the between-groups effects when compared to controls.

Conclusions

Brief, targeted single-session sexual risk reduction interventions demonstrate a small but significant effect and should be prioritized.
  相似文献   
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Sica J  Burch J 《British journal of nursing (Mark Allen Publishing)》2007,16(13):772, 774, 776-772, 774, 777
Intestinal failure and a high faecal output from a stoma or fistula are rare gastrointestinal complications. Intestinal failure occurs when the intestine fails to absorb sufficient fluids and nutrients to maintain life, and can result from bowel resection or malabsorption. The management of these conditions raises many issues which nurses caring for affected patients need to consider. This article will discuss those relating to feeding, appliances and medication. Two methods of feeding that can be useful in patients with intestinal failure, namely parenteral nutrition (intravenous feeding) and fistuloclysis (feeding via an intestinal fistula), will be explored. Finally, a short case study will be presented to highlight the effects of some of these interventions and the problems that they can cause for patients.  相似文献   
998.
Tibiofemoral shape influences knee kinematics but little is known about the effect of shape on deep knee flexion kinematics. The aim of this study was to examine the association between tibiofemoral joint shape and kinematics during deep kneeling in patients with and without osteoarthritis (OA). Sixty-one healthy participants and 58 patients with end-stage knee OA received a computed tomography (CT) of their knee. Participants completed full flexion kneeling while being imaged using single-plane fluoroscopy. Six-degree-of-freedom kinematics were measured by registering a three-dimensional (3D)-static CT onto 2D-dynamic fluoroscopic images. Statistical shape modeling and bivariate functional principal component analysis (bfPCA) were used to describe variability in knee shape and kinematics, respectively. Random-forest-regression models were created to test the ability of shape to predict kinematics controlling for body mass index, sex, and group. The first seven modes of the shape model up to three modes of the bfPCAs captured more than 90% of the variation. The ability of the random forest models to predict kinematics from shape was low, with no more than 50% of the variation being explained in any model. Furthermore, prediction errors were high, ranging between 24.2% and 29.4% of the data. Variations in the bony morphology of the tibiofemoral joint were weakly associated with the kinematics of deep knee flexion. The models only explained a small amount of variation in the data with high error rates indicating that additional predictors need to be identified. These results contribute to the clinical understanding of knee kinematics and potentially the expectations placed on high-flexion total knee replacement design.  相似文献   
999.
An attentional bias toward threat may be one mechanism underlying clinical anxiety. Attention bias modification (ABM) aims to reduce symptoms of anxiety disorders by directly modifying this deficit. However, existing ABM training programs have not consistently modified attentional bias and may not reflect optimal learning needs of participants (i.e., lack of explicit instruction, training goal unclear to participants, lack of feedback, non-adaptive, inability to differentiate or target different components of attentional bias). In the current study, we introduce a new adaptive ABM program (AABM) and test its feasibility in individuals with social anxiety disorder. We report task characteristics and preliminary evidence that this task consistently modifies attentional bias and that changes in attentional bias (but not number of trials) correlate with the level of symptom reduction. These results suggest that AABM may be a targeted method for the next generation of studies examining the utility of attention training.  相似文献   
1000.
Gold nanoparticles grown within the intracellular confines of living cells are introduced as potential surface-enhanced Raman scattering (SERS) substrates for confocal Raman spectrometry. Electron microscopy and a silver-enhanced reflectance laser scanning confocal microscopic approach were used to visualize the size, shape, and distribution of intracellularly grown gold nanoparticles (IGAuN) as small as 1 nm. Passive uptake as the conventional approach for delivering nanoparticles inside cells faces the insurmountable challenge of escaping the endosomal/lysosomal pathway. In contrast, IGAuN provides an unprecedented advantage of providing access to cytoplasm and nucleus.  相似文献   
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