首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8430篇
  免费   569篇
  国内免费   52篇
耳鼻咽喉   44篇
儿科学   223篇
妇产科学   249篇
基础医学   1383篇
口腔科学   182篇
临床医学   910篇
内科学   1680篇
皮肤病学   182篇
神经病学   849篇
特种医学   291篇
外国民族医学   7篇
外科学   736篇
综合类   42篇
一般理论   2篇
预防医学   712篇
眼科学   86篇
药学   658篇
中国医学   19篇
肿瘤学   796篇
  2024年   11篇
  2023年   64篇
  2022年   113篇
  2021年   216篇
  2020年   153篇
  2019年   203篇
  2018年   210篇
  2017年   171篇
  2016年   239篇
  2015年   244篇
  2014年   350篇
  2013年   416篇
  2012年   676篇
  2011年   802篇
  2010年   421篇
  2009年   379篇
  2008年   606篇
  2007年   652篇
  2006年   607篇
  2005年   581篇
  2004年   493篇
  2003年   402篇
  2002年   390篇
  2001年   54篇
  2000年   45篇
  1999年   68篇
  1998年   83篇
  1997年   79篇
  1996年   65篇
  1995年   45篇
  1994年   44篇
  1993年   32篇
  1992年   31篇
  1991年   14篇
  1990年   9篇
  1989年   6篇
  1988年   5篇
  1987年   5篇
  1986年   10篇
  1985年   8篇
  1984年   7篇
  1983年   8篇
  1982年   4篇
  1981年   3篇
  1980年   4篇
  1979年   3篇
  1974年   2篇
  1973年   2篇
  1970年   4篇
  1968年   2篇
排序方式: 共有9051条查询结果,搜索用时 15 毫秒
71.
Many pregnancies are lost during early gestation, but clinicians still lack tools to recognize risk factors for miscarriage. Thus, the identification of risk factors for miscarriage during the first trimester in women with no obvious risk for a pregnancy loss was the aim of this prospective cohort trial. A total of 1098 women between gestation weeks 4 and 12 in whom no apparent signs of a threatened pregnancy could be diagnosed were recruited. Demographic, anamnestic, psychometric and biological data were documented at recruitment and pregnancy outcomes were registered subsequently. Among the cases with sufficiently available data, 809 successfully progressing pregnancies and 55 subsequent miscarriages were reported. In this cohort, risk of miscarriage was significantly increased in women at higher age (>33 years), lower body mass index (< or =20 kg/ m(2)) and lower serum progesterone concentrations (< or =12 ng/ml) prior to the onset of the miscarriage. Women with subsequent miscarriage also perceived higher levels of stress/demands (supported by higher concentrations of corticotrophin-releasing hormone) and revealed reduced concentrations of progesterone-induced blocking factor. These risk factors were even more pronounced in the subcohort of women (n = 335) recruited between gestation weeks 4 and 7. The identification of these risk factors and development of an interaction model of these factors, as introduced in this article, will help clinicians to recognize pregnant women who require extra monitoring and who might benefit from therapeutic interventions such as progestogen supplementation, especially during the first weeks of pregnancy, to prevent a miscarriage.  相似文献   
72.
73.
74.
75.
Background: Alongside metabolic diseases (esp. obesity), allergic disorders are becoming increasingly prevalent. Since both obesity and allergies are highly impacted by environmental determinants, with this study we assessed the potential link between metabolic implications and two distinct types of allergies. Methods: Using cross-sectional data from the German FoCus cohort, n = 385 allergy cases, either hay fever (=type I allergy, n = 183) or contact allergy (=type IV allergy, n = 202) were compared to age- and sex-matched healthy control subjects (1:1 ratio, in total n = 770) regarding their metabolic phenotype, diet, physical activity, sleep, gut microbial composition, and serum metabolite profile using suitable BMI-adjusted models. Results: Obesity and metabolic alterations were found significantly more prevalent in subjects with allergies. In fact, this relation was more pronounced in contact allergy than hay fever. Subsequent BMI-adjusted analysis reveals particular importance of co-occurring hyperlipidaemia for both allergy types. For contact allergy, we revealed a strong association to the dietary intake of poly-unsaturated fatty acids, particularly α-linolenic acid, as well as the enrichment of the corresponding metabolic pathway. For hay fever, there were no major associations to the diet but to a lower physical activity level, shorter duration of sleep, and an altered gut microbial composition. Finally, genetic predisposition for hyperlipidaemia was associated to both contact allergy and hay fever. Conclusions: Reflected by higher allergy prevalence, our findings indicate an impaired immune response in obesity and hyperlipidaemia, which is differentially regulated in type I and type IV allergies by an unfavourable lifestyle constellation and subsequent microbial and metabolic dysfunctions.  相似文献   
76.
77.
Background The addition of adjuvant capecitabine to standard chemotherapy of early-stage triple-negative breast cancer (TNBC) patients has improved survival in a few randomised trials and in meta-analyses. However, many patients did not benefit. We evaluated the BRCA1-like DNA copy number signature, indicative of homologous recombination deficiency, as a predictive biomarker for capecitabine benefit in the TNBC subgroup of the FinXX trial.Methods Early-stage TNBC patients were randomised between adjuvant capecitabine-containing (TX + CEX: capecitabine-docetaxel, followed by cyclophosphamide-epirubicin-capecitabine) and conventional chemotherapy (T + CEF: docetaxel, followed by cyclophosphamide-epirubicin-fluorouracil). Tumour BRCA1-like status was determined on low-coverage, whole genome next-generation sequencing data using an established DNA comparative genomic hybridisation algorithm.Results For 129/202 (63.9%) patients the BRCA1-like status could be determined, mostly due to lack of tissue. During a median follow-up of 10.7 years, 35 recurrences and 32 deaths occurred. Addition of capecitabine appears to improve recurrence-free survival more among 61 (47.3%) patients with non-BRCA1-like tumours (HR 0.23, 95% CI 0.08–0.70) compared to 68 (52.7%) patients with BRCA1-like tumours (HR 0.66, 95% CI 0.24–1.81) (P-interaction = 0.17).Conclusion Based on our data, patients with non-BRCA1-like TNBC appear to benefit from the addition of capecitabine to adjuvant chemotherapy. Patients with BRCA1-like TNBC may also benefit. Additional research is needed to define the subgroup within BRCA1-like TNBC patients who may not benefit from adjuvant capecitabine.Subject terms: Breast cancer, Translational research, Predictive markers, Breast cancer  相似文献   
78.
79.
Anecdotally there are high rates of domestic violence in the small Micronesian State of Yap, Federated States of Micronesia (FSM), but there have been no studies to quantify the prevalence or characteristics of domestic violence in Yap or in any other state of the FSM. A survey was administered to women at the Yap hospital and community health centers from February through June 2011. Survey data were on domestic violence, which was supplemented by a focus group to explore the issues involved in greater detail. A high prevalence of domestic violence was documented by the survey; perceptions about this were explored in the focus group. On the questionnaire, 148 of 194 (76%) women reported at least one form of abuse. Given the small number of adult women in Yap, these findings suggest that domestic violence is a serious, pervasive problem that Yap needs urgently to address. The issue clearly needs to be investigated throughout the other states of the FSM and addressed at the national policy level as well as at the state level.  相似文献   
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号