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   383篇
  免费   24篇
耳鼻咽喉   3篇
儿科学   3篇
妇产科学   2篇
基础医学   53篇
口腔科学   12篇
临床医学   28篇
内科学   108篇
皮肤病学   7篇
神经病学   52篇
特种医学   17篇
外科学   40篇
综合类   1篇
预防医学   17篇
眼科学   4篇
药学   31篇
肿瘤学   29篇
  2023年   2篇
  2022年   8篇
  2021年   8篇
  2019年   4篇
  2018年   5篇
  2017年   6篇
  2016年   8篇
  2015年   11篇
  2014年   13篇
  2013年   16篇
  2012年   28篇
  2011年   25篇
  2010年   20篇
  2009年   15篇
  2008年   26篇
  2007年   21篇
  2006年   30篇
  2005年   30篇
  2004年   18篇
  2003年   24篇
  2002年   13篇
  2001年   3篇
  2000年   4篇
  1999年   4篇
  1998年   3篇
  1997年   3篇
  1995年   2篇
  1993年   2篇
  1992年   4篇
  1991年   4篇
  1990年   2篇
  1987年   1篇
  1986年   1篇
  1985年   3篇
  1984年   1篇
  1983年   1篇
  1978年   1篇
  1977年   3篇
  1975年   3篇
  1974年   3篇
  1973年   1篇
  1971年   3篇
  1970年   6篇
  1969年   2篇
  1968年   5篇
  1967年   2篇
  1966年   1篇
  1965年   3篇
  1956年   1篇
  1955年   2篇
排序方式: 共有407条查询结果,搜索用时 15 毫秒
401.
To study the characteristics and clinical impact of therapy-related acute myeloid leukemia (t-AML). 200 patients (7.0%) had t-AML and 2653 de novo AML (93%). Patients with t-AML were older (P < .0001) and they had lower white blood counts (P = .003) compared with de novo AML patients; t-AML patients had abnormal cytogenetics more frequently, with overrepresentation of 11q23 translocations as well as adverse cytogenetics, including complex and monosomal karyotypes, and with underrepresentation of intermediate-risk karyotypes (P < .0001); t-AML patients had NPM1 mutations (P < .0001) and FLT3 internal tandem duplications (P = .0005) less frequently. Younger age at diagnosis of primary malignancy and treatment with intercalating agents as well as topoisomerase II inhibitors were associated with shorter latency periods to the occurrence of t-AML. In multivariable analyses, t-AML was an adverse prognostic factor for death in complete remission but not relapse in younger intensively treated patients (P < .0001 and P = .39, respectively), relapse but not death in complete remission in older, less intensively treated patients (P = .02 and P = .22, respectively) and overall survival in younger intensively treated patients (P = .01). In more intensively treated younger adults, treatment-related toxicity had a major negative impact on outcome, possibly reflecting cumulative toxicity of cancer treatment.  相似文献   
402.
In classic concentric/eccentric exercise, the same absolute load is applied in concentric and eccentric actions, which infers a smaller relative eccentric load. We compared the effects of 6 weeks of classic concentric/eccentric quadriceps strength training (CON/ECC, 11 subjects) to eccentric overload training (CON/ECC+, 14 subjects) in athletes accustomed to regular strength training. The parameters determined included functional tests, quadriceps and fibre cross-sectional area (CSA), fibre type distribution by ATPase staining, localisation of myosin heavy chain (MHC) isoform mRNAs by situ hybridization and the steady-state levels of 48 marker mRNAs (RT-PCR) in vastus lateralis biopsies taken before and after training. Both training forms had anabolic effects with significant increases in quadriceps CSA, maximal strength, ribosomal RNA content and the levels of mRNAs involved in growth and regeneration. Only the CON/ECC+ training led to significantly increased height in a squat jump test. This was accompanied by significant increases in IIX fibre CSA, in the percentage of type IIA fibres expressing MHC IIx mRNA, in the level of mRNAs preferentially expressed in fast, glycolytic fibres, and in post-exercise capillary lactate. The enhanced eccentric load apparently led to a subtly faster gene expression pattern and induced a shift towards a faster muscle phenotype plus associated adaptations that make a muscle better suited for fast, explosive movements.  相似文献   
403.
Consumers are exposed to organotin compounds (OTCs) via contaminated fish and seafood due to the accumulation of these compounds in marine organisms. Certain OTCs are immunotoxic and may also have endocrine disrupting properties resulting in adverse effects on the reproductive tract in mollusks and mammals. Since effects of in utero exposure to endocrine disrupting chemicals on the reproductive system are dependent on the critical window of exposure during its development, we conducted a comprehensive study with the aim to identify the most sensitive window of exposure to TPTCl and to investigate the effects of pre- and postnatal treatment on sexual development in rats. Male and female offspring rats were exposed to 2 or 6 mg TPTCl/kg b.w. and day either in utero and during lactation (gestation day 6 until weaning on PND 21) or from gestation day 6 until termination. As previously reported, offspring in the 6 mg TPTCl dose group exhibited high perinatal mortality and therefore no further evaluation was carried out at this dose level (Grote, K., Hobler, C, Andrade, A.J.M., Wichert Grande, S., Gericke, C., Talsness, C.E., Appel, K.E., Chahoud, I., 2007. Effects of in utero and lactational exposure to triphenyltin chloride on pregnancy outcome and postnatal development in rat offspring. Toxicology 238, 177–185). In the present paper, results on postnatal development obtained from surviving offspring of dams exposed to 2 mg TPTCl/kg b.w. are reported. Male offspring were sacrificed on PND 64 or 65 and female offspring at first estrus after PND 58. A clear sex difference in response to treatment was observed. Male postnatal development was severely affected with decreases in body weight gain, reproductive organ weights and testosterone concentration as well as a significant delay in the age at preputial separation. In contrast, females exhibited a precocious completion of vaginal opening while all other endpoints were unaffected. Most of these effects were already present in animals that were only exposed until weaning indicating that these effects may be irreversible and continued treatment until termination had contributed less than expected to the severity of the observed effects. The results of the present study suggest that the sensitive window for the evaluated endpoints seems to be the period of prenatal development and that male offspring rats were more susceptible to treatment.  相似文献   
404.
405.
Though it has long been recognised that there is a hereditary component to the obstructive sleep apnoea/hypopnoea syndrome (OSAHS), identifying its genetic basis remains elusive. Hypertension and metabolic syndrome, like OSAHS, are polygenic disorders, physiologically complex and the product of highly organised, hierarchical systems within the body. Elucidating their genetic basis is difficult when they are considered in isolation but even more difficult if their interrelationships with each other are brought into play. Not least of the problems is the lack of adequate and consistent phenotyping, which has hampered genetic dissection of these diseases; in addition, sleep-disordered breathing has not been factored into most studies dealing with essential hypertension or metabolic syndrome. Genome-wide scans have yielded inconsistent results in all three disorders under discussion and candidate gene studies of possible regulatory molecules require more rigorous replication. One approach would be to use 'intermediate' phenotypes and dense mapping of candidate genes for identifying genotype-phenotype correlations. This review focuses on genetic factors, which may be responsible for the expression of cardiovascular disease and metabolic syndrome in the context of OSAHS.  相似文献   
406.
407.
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