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51.
Outdoor air pollution is a major environmental health problem throughout the world. In particular, exposure to particulate matter (PM) has been associated with the development and exacerbation of several respiratory diseases, including asthma. Although the adverse health effects of PM have been demonstrated for many years, the underlying mechanisms have not been fully identified. In this review, we focus on the role of the lung epithelium and specifically highlight multiple cytokines in PM‐induced respiratory responses. We describe the available literature on the topic including in vitro studies, findings in humans (ie observations in human cohorts, human controlled exposure and ex vivo studies) and in vivo animal studies. In brief, it has been shown that exposure to PM modulates the airway epithelium and promotes the production of several cytokines, including IL‐1, IL‐6, IL‐8, IL‐25, IL‐33, TNF‐α, TSLP and GM‐CSF. Further, we propose that PM‐induced type 2‐promoting cytokines are important mediators in the acute and aggravating effects of PM on airway inflammation. Targeting these cytokines could therefore be a new approach in the treatment of asthma.  相似文献   
52.
Aim: The mechanism linking exercise intensity to the magnitude of the immune response is not completely understood. The purpose of this investigation was to determine whether the immune response to resistance exercise was associated with (1) changes in workload or (2) anaerobic exercise intensity. Methods: Previously untrained women underwent 6 months of resistance training for lower and upper body (TOTAL, n = 34) or for upper body alone (UPPER, n = 30). Lymphocyte subsets [T (CD3+), CD4+, CD8+, NK and B], functional markers (CD45RA+ and CD45RO+), and mitogen (phytohemagglutinin‐M, concanavalin A and pokeweed mitogen) and superantigen (staphylococcus a. cowans)‐stimulated proliferation were measured from blood samples collected pre‐ and post‐exercise for a squat resistance exercise consisting of six sets of 10 repetitions at 75% of one repetition maximum. This protocol was performed before (T0) and after 3 (T3) and 6 months (T6) of training. Results: Lymphocyte recruitment to the circulation and proliferation following resistance exercise did not differ between training groups at any time, although the TOTAL group performed at a higher workload as training progressed. With respect to anaerobic intensity, exercise‐induced increases in NK, CD4+, CD8+ and B lymphocyte concentrations were 42 (P = 0.07), 76 (P < 0.05), 72 (P < 0.05) and 242% (P < 0.01) greater in women in the highest compared with the lowest post‐exercise lactate quartiles. Lymphocyte proliferation did not differ between lactate quartiles. Conclusions: Anaerobic intensity, rather than increased strength and workload, is associated with the number of lymphocytes recruited to the circulation, but not T and B cell proliferation responses.  相似文献   
53.
54.
Adenosine and active hyperemia in dog skeletal muscle   总被引:5,自引:0,他引:5  
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55.
BACKGROUND: In a Danish population-based cohort study assessing the risk of cerebral palsy in children born after IVF, we made some interesting observations regarding 'vanishing co-embryos'. METHODS and RESULTS: All live-born children born in Denmark from 1 January 1995 to 31 December 2000 were included in this analysis. The children conceived by IVF/ICSI (9444) were identified through the IVF Register, the children conceived without IVF/ICSI (395 025) were identified through The Danish Medical Birth Register. Main outcome measure was the incidence of cerebral palsy. Within the IVF/ICSI children we found indications of an increased risk of cerebral palsy in those children resulting from pregnancies, where the number of embryos transferred was higher than the number of children born. CONCLUSIONS: The association between vanishing embryo syndrome and incidence of cerebral palsy following IVF requires further investigation in larger, adequately powered, studies.  相似文献   
56.
Like many bacterial pathogens, Neisseria gonorrhoeae must adapt to environmental changes in order to successfully colonize and proliferate in a new host. Modulation of gene expression in response to environmental signals is an efficient mechanism used by bacteria to achieve this goal. Using DNA microarrays and a tissue culture model for gonococcal infection, we examined global changes in gene expression in N. gonorrhoeae in response to adherence to host cells. Among those genes induced upon adherence to human epithelial cells in culture was rpoH, which encodes a homolog of the heat shock sigma factor, sigma(32) (RpoH), as well as genes of the RpoH regulon, groEL and groES. Attempts to construct an rpoH null mutant in N. gonorrhoeae were unsuccessful, suggesting that RpoH is essential for viability of N. gonorrhoeae. The extracytoplasmic sigma factor, RpoE (sigma(E)), while known to regulate rpoH in other bacteria, was found not to be necessary for the up-regulation of rpoH in gonococci upon adherence to host cells. To examine the role of RpoH in host cell interactions, an N. gonorrhoeae strain conditionally expressing rpoH was constructed. The results of our experiments showed that while induction of rpoH expression is not necessary for adherence of gonococci to epithelial cells, it is important for the subsequent invasion step, as gonococci depleted for rpoH invade cells two- to threefold less efficiently than a wild-type strain. Taken together, these results indicate that sigma(32), but not sigma(E), is important for the response of gonococci in the initial steps of an infection.  相似文献   
57.
Although the role of the reproductive hormone, relaxin, in rodents is well documented, its potential contribution to human reproduction is less well defined. In this study, we examine the effects of relaxin on human endometrial cells in vitro and describe the clinical effects of relaxin on menstrual flow in women. In cultured endometrial cells, relaxin specifically induces the expression of an angiogenic agent, vascular endothelial growth factor (VEGF). cAMP is implicated as a second messenger involved in VEGF stimulation. VEGF expression is temporally regulated in the endometrium, and our results suggest that relaxin, which is secreted by the corpus luteum and is present in the endometrium during the menstrual cycle and pregnancy, may be involved in regulating endometrial VEGF expression. Relaxin was recently tested in a clinical trial for efficacy in the treatment of progressive systemic sclerosis, and was administered at levels up to 10 times higher than that measured during pregnancy. The most frequent relaxin-related adverse event reported during the course of the study was the onset of menometrorrhagia, defined in this study as heavier-than-usual or irregular menstrual bleeding. The intensification of menstrual flow observed in these patients is consistent with the hypothesis that relaxin mediates neovascularization of the endometrial lining.  相似文献   
58.
We investigated the impact of pre-existing mental ill health on postpartum maternal outcomes. Women reporting childbirth trauma received counselling (Promoting Resilience in Mothers' Emotions; n?=?137) or parenting support (n?=?125) at birth and 6 weeks. The EuroQol Five dimensional (EQ-5D)-measured health-related quality of life at 6 weeks, 6 and 12 months. At 12 months, EQ-5D was better for women without mental health problems receiving PRIME (mean difference (MD) 0.06; 95 % confidence interval (CI) 0.02 to 0.10) or parenting support (MD 0.08; 95 % CI 0.01 to 0.14). Pre-existing mental health conditions influence quality of life in women with childbirth trauma.  相似文献   
59.
The reproductive histories of 74 post-menarcheal Agta Negrito women, tropical foragers of Cagayan province, north-eastern Luzon, the Philippines are described and analysed in comparison with data collected by Howell on Dobe! Kung hunter-gatherers. Among the Agta, mean age at menarche is 17, mean age at first live birth is 20·14 years, mean completed parity is 6·53 and mean age at menopause is 44. Average height is 141·24cm and average weight 36·72 kg. No time trends were detected in age at menarche and age at first live birth among the Agta. Average spacing between live births where an infant survives until the birth of the next sibling was 2·85 years. Compared to the Dobe !Kung, Agta women have later menarche, but shorter birth spacing and a longer active childbearing span.  相似文献   
60.
Fifty-eight women with severe preeclampsia between 28-34 weeks' gestation qualified for a randomized controlled trial to establish whether elective delivery 48 hours after administration of betamethasone (aggressive-management group) or delivery later as indicated by maternal or fetal condition (expectant-management group) was more beneficial to maternal and fetal outcome. Twenty women who qualified were not randomized because they developed maternal or fetal indications necessitating delivery within 48 hours; these newborns developed most of the complications. Expectant management was not associated with an increase in maternal complications, but it significantly prolonged the gestational age (mean 7.1 days; P less than .05), reduced the number of neonates requiring ventilation (P less than .05), and reduced the number of neonatal complications (P less than .05).  相似文献   
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