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81.
82.

Background

Early in medical education, physicians must develop competencies needed for tobacco dependence treatment.

Objective

To assess the effect of a multi-modal tobacco dependence treatment curriculum on medical students’ counseling skills.

Design

A group-randomized controlled trial (2010–2014) included ten U.S. medical schools that were randomized to receive either multi-modal tobacco treatment education (MME) or traditional tobacco treatment education (TE).

Setting/Participants

Students from the classes of 2012 and 2014 at ten medical schools participated. Students from the class of 2012 (N?=?1345) completed objective structured clinical examinations (OSCEs), and 50 % (N?=?660) were randomly selected for pre-intervention evaluation. A total of 72.9 % of eligible students (N?=?1096) from the class of 2014 completed an OSCE and 69.7 % (N?=?1047) completed pre and post surveys.

Interventions

The MME included a Web-based course, a role-play classroom demonstration, and a clerkship booster session. Clerkship preceptors in MME schools participated in an academic detailing module and were encouraged to be role models for third-year students.

Measurements

The primary outcome was student tobacco treatment skills using the 5As measured by an objective structured clinical examination (OSCE) scored on a 33-item behavior checklist. Secondary outcomes were student self-reported skills for performing 5As and pharmacotherapy counseling.

Results

Although the difference was not statistically significant, MME students completed more tobacco counseling behaviors on the OSCE checklist (mean 8.7 [SE 0.6] vs. mean?8.0 [SE 0.6], p?=?0.52) than TE students. Several of the individual Assist and Arrange items were significantly more likely to have been completed by MME students, including suggesting behavioral strategies (11.8 % vs. 4.5 %, p?<?0.001) and providing information regarding quitline (21.0 % vs. 3.8 %, p?<?0.001). MME students reported higher self-efficacy for Assist, Arrange, and Pharmacotherapy counseling items (ps?≤0.05).

Limitations

Inclusion of only ten schools limits generalizability.

Conclusions

Subsequent interventions should incorporate lessons learned from this first randomized controlled trial of a multi-modal longitudinal tobacco treatment curriculum in multiple U.S. medical schools.NIH Trial Registry Number: NCT01905618
  相似文献   
83.
Cyclin E is an important regulator of cell cycle progression that together with cyclin-dependent kinase (cdk) 2 is crucial for the G1/S transition during the mammalian cell cycle. Previously, we showed that severe overexpression of cyclin E protein in tumor cells and tissues results in the appearance of lower molecular weight isoforms of cyclin E, which together with cdk2 can form a kinase complex active throughout the cell cycle. In this study, we report that one of the substrates of this constitutively active cyclin E/cdk2 complex is retinoblastoma susceptibility gene product (pRb) in populations of breast cancer cells and tissues that also overexpress p16. In these tumor cells and tissues, we show that the expression of p16 and pRb is not mutually exclusive. Overexpression of p16 in these cells results in sequestering of cdk4 and cdk6, rendering cyclin D1/cdk complexes inactive. However, pRb appears to be phosphorylated throughout the cell cycle following an initial lag, revealing a time course similar to phosphorylation of glutathione S-transferase retinoblastoma by cyclin E immunoprecipitates prepared from these synchronized cells. Hence, cyclin E kinase complexes can function redundantly and replace the loss of cyclin D-dependent kinase complexes that functionally inactivate pRb. In addition, the constitutively overexpressed cyclin E is also the predominant cyclin found in p107/E2F complexes throughout the tumor, but not the normal, cell cycle. These observations suggest that overexpression of cyclin E in tumor cells, which also overexpress p16, can bypass the cyclin D/cdk4-cdk6/p16/pRb feedback loop, providing yet another mechanism by which tumors can gain a growth advantage.  相似文献   
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The purpose of this study was to determine whether nitrate supplementation augments cutaneous reactive hyperaemia. Seven participants were tested pre‐ and postnitrate supplementation (25 ml beetroot juice); participants consumed one shot per day for 3 days. Participants were instrumented with two microdialysis fibres: control (Ringer's solution) and NO synthase inhibition (20 mM L‐NAME). Skin blood flow was measured via laser‐Doppler flowmetry (LDF). A blood pressure cuff was placed on the experimental arm and inflated to 250 mmHg for 5 mins to occlude arterial inflow. The cuff was released, and the resultant reactive hyperaemia was measured. Blood pressure was continuously measured via plethysmography from a finger on the non‐experimental arm. Cutaneous vascular conductance was calculated (LDF/MAP) and normalized to maximal vasodilatation (%CVCmax). Only diastolic blood pressure was reduced following nitrate supplementation (71 ± 2 vs. 66 ± 1 mmHg; P<0·05). There was no effect of nitrate supplementation on peak reactive hyperaemia at control (Pre: 52 ± 3 vs. Post: 57 ± 2%CVCmax) or L‐NAME (Pre: 52 ± 2 vs. Post: 59 ± 4%CVCmax) sites. There was no effect of nitrate supplementation on total reactive hyperaemia at either control (Pre: 4197 ± 943 vs. Post: 4523 ± 1040%CVCmax * sec) or L‐NAME (Pre: 5108 ± 997 vs. Post: 5694 ± 1002%CVCmax * sec) sites. These data suggest cutaneous reactive hyperaemia is unaffected by dietary nitrate supplementation in healthy humans.  相似文献   
86.
As momentum grows for a sustainable urbanisation goal in the post-2015 development agenda, this paper reports on an action research study that sought to tackle the urban health divide by enabling intersectoral action on social determinants at the local level. The study was located in the cities of Mombasa in Kenya and Valparaíso in Chile, and the impact of the intervention on child nutrition was evaluated using a controlled design. The findings showed that an action research process using the social educational process known as PLA could effectively build the capacity of multisectoral teams to take coordinated action which in turn built the capacity of communities to sustain them. The impact on child nutrition was inconclusive and needed to be interpreted within the context of economic collapse in the intervention area. Four factors were found to have been crucial for creating the enabling environment for effective intersectoral action (i) supportive government policy (ii) broad participation and capacity building (iii) involving policy makers as advisors and establishing the credibility of the research and (iii) strengthening community action. If lessons learned from this study can be adapted and applied in other contexts then they could have a significant economic and societal impact on health and nutrition equity in informal urban settlements.  相似文献   
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88.
Thyroid-associated ophthalmopathy (TAO) is thought to be a T-cell-mediated autoimmune disorder. We sought to characterize abnormalities in the peripheral blood T-cell subsets in patients with TAO, and examine whether the long-acting somatostatin analogue, octreotide-LAR, treatment affects these cells. We analyzed peripheral blood T-cell subsets by flow cytometry in 26 euthyroid patients with moderately severe active TAO and 24 controls. Twenty-five of the patients with TAO were enrolled in a randomized trial to receive either 30 mg of octreotide-LAR (n = 11) or placebo (n = 14) every 4 weeks for 16 weeks; all 25 patients subsequently received octreotide-LAR 30 mg every 4 weeks from week 16 to 32. T-cell subsets were analysed at baseline, week 16, and week 32. At baseline, the relative percentage of CD4+ helper T-cells (p = 0.0003) and the CD4+/CD8+ ratio (p = 0.008) were significantly higher in patients with TAO compared to controls. Patients with TAO had higher na?ve active T cells (CD45RA+, CD45RA+ CD4+) and lower memory T cells (CD45RO+, CD45RO+ CD4+) than controls. At weeks 16 and 32, there were no significant differences in any T-cell subsets between the octreotide-LAR-treated and placebo groups. These results support a role of T cell in the pathogenesis of TAO, and show that octreotide-LAR has no effect on T-cell subsets during 32-weeks of treatment.  相似文献   
89.
We investigated whether HIV-1 antigen-specific CD4(+) T cells expressed the viral coreceptor CCR5 during primary HIV-1 infection (PHI). In the peripheral blood of subjects with very early PHI (< 22 days after onset of symptoms), there was a 10- to 20-fold increase in the proportion of highly activated (CD38(+++)) and proliferating (Ki-67(+)) CD4(+) T cells that expressed CCR5(+), and were mostly T-cell intracellular antigen-1 (TIA-1)(+) perforin(+) granzyme B(+). Inthe same patient samples, CD4(+) T cells producing interferon (IFN)-gamma in response to HIV group-specific antigen (Gag) peptides were readily detected (median, 0.58%) by intracellular cytokine assay-these cells were again predominantly CD38(+++), Ki-67(+), and TIA-(++), as well as Bcl-2(low). On average, 20% of the Gag-specific CD4(+) T cells also expressed interleukin-2 (IL-2) and were CD127 (IL-7R)(+). Taken together, these results suggest that Gag-specific T-helper 1 (Th1) effector cells express CCR5 during the primary response and may include precursors of long-term self-renewing memory cells. However, in PHI subjects with later presentation, antigen-specific CD4(+) T cells could not be readily detected (median, 0.08%), coinciding with a 5-fold lower level of the CCR5(+)CD38(+++) CD4(+) T cells. These results suggest that the antiviral response to HIV-1 infection includes highly activated CCR5(+)CD4(+) cytotoxic effector cells, which are susceptible to both apoptosis and cytopathic infection with HIV-1, and rapidly decline.  相似文献   
90.
Background and Objectives: We investigated the possibility that a variant of the normal colonic flora, a high concentration of methanogeas, influences the host's response to ingestion of nonabsorbable, fermentable materials. Methods: To better evaluate symptomatic and breath H2 and methane (CH4) responses, subjects were placed on a basal diet (primarily rice and hamburger) that contained minimal amounts of nonabsorbable, fermentable substrate. A breath CH4/H2 ratio of greater or less than 1 on the second day of the basal diet was used to categorize subjects as high (N = 9) or low (N = 25) CH4 producers. After stabilization of the breath gas excretion (day 3 or 4 on the basal diet), the subjects ingested either sorbitol (8.8 g) or oat fiber (10.2 g). Results: The low CH4 producers had a signficantly higher ( p < 0.05) breath H2 concentration than the high producers on the basal diet and after ingestion of sorbitol (27.1 ± 2.7 ppm vs 15.8 ± 3.6 ppm) or oat fiber (13.1 ± 0.08 ppm vs 9.6 ± 1.2 ppm). Low producers of methane reported significantly increased bloating and cramping after sorbitol ingestion and increased bloating after fiber ingestion, whereas high CH4 producers reported no signficant increase in these symptoms. Conclusion: The presence of a methanogenic flora is associated with a reduced symptomatic response to ingestion of nonabsorbable, fermentable material in healthy subjects. Manipulation of the normal flora could be of therapeutic value in nonmethanogenic patients with irritable bowel syndrome.  相似文献   
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