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   16133篇
  免费   1324篇
  国内免费   289篇
耳鼻咽喉   69篇
儿科学   1509篇
妇产科学   991篇
基础医学   1393篇
口腔科学   172篇
临床医学   1459篇
内科学   2114篇
皮肤病学   52篇
神经病学   965篇
特种医学   278篇
外科学   1142篇
综合类   1666篇
一般理论   1篇
预防医学   3148篇
眼科学   154篇
药学   1777篇
  5篇
中国医学   445篇
肿瘤学   406篇
  2024年   37篇
  2023年   288篇
  2022年   359篇
  2021年   729篇
  2020年   550篇
  2019年   652篇
  2018年   579篇
  2017年   617篇
  2016年   583篇
  2015年   576篇
  2014年   1038篇
  2013年   1377篇
  2012年   889篇
  2011年   994篇
  2010年   788篇
  2009年   747篇
  2008年   835篇
  2007年   770篇
  2006年   624篇
  2005年   587篇
  2004年   486篇
  2003年   442篇
  2002年   348篇
  2001年   297篇
  2000年   247篇
  1999年   194篇
  1998年   184篇
  1997年   143篇
  1996年   125篇
  1995年   121篇
  1994年   121篇
  1993年   103篇
  1992年   98篇
  1991年   87篇
  1990年   83篇
  1989年   63篇
  1988年   67篇
  1987年   57篇
  1986年   68篇
  1985年   120篇
  1984年   108篇
  1983年   88篇
  1982年   70篇
  1981年   69篇
  1980年   65篇
  1979年   60篇
  1978年   51篇
  1977年   29篇
  1976年   37篇
  1973年   22篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
目的:建立测定生长激素(GH)在体生物活性的方法.方法:以去垂体大鼠体重增长(BWG)和胫骨骺软骨板宽度(TEW)为指标,观察动物性别、给药途径、次数和周期不同对效应的影响;同时进行4dBWG,6dBWG和6dTEW法,测定GH的效价(平行线3×3设计).结果:♀和♂sc和im给药以及每日给药1次和2次的BWG和TEW差异无显著意义.给药6d比给药4d引起较大的BWG和TEW(P<005).4dBWG法和6dBWG法在0020-0500IU·d-1有较好的λ值(00660和01747)和r值(09000和09237);4dBWG,6dBWG和6dTEW法测得rhGH的效价为46132,39829和48023IU/amp.6dBWG法有较小的λ值和较低的ARFL值.结论:可在同一组去垂体大鼠体内同时用4dBWG,6dBWG和6dTEW法测GH活性,以6dBWG法较好.  相似文献   
82.
In recent decades, there has been a dramatic increase in unhealthy weight for both children and adults. The Canadian standard of living has changed in favour of more easily prepared, calorie-dense foods and sedentary practices. Many family characteristics have also changed over the past 50 years. More Canadian families are living in disadvantaged situations, forecasting a host of unhealthy behaviours and attitudes in adults. The poor are not only getting poorer, they are also becoming heavier. Children from disadvantaged families seem to be leading the trend in increasing prevalence of unhealthy weight. Because they live in neighbourhoods that are perceived as unsafe, these children are likely spending more time indoors. This is associated with watching more television, which not only displaces other forms of educational and active entertainment but also places them at risk of learning inaccurate information about proper eating. Social science research helps identify factors contributing most to the rise in excess weight within this population, thus providing essential clues for effective approaches to its eradication.  相似文献   
83.
Fourteen adult patients (mean age 22.5 years, range 18–35) with cystic fibrosis undertook nocturnal nasogastric feeding for a mean period of 14.7 (range 6–18) months consuming an average of 1042 ml of a high energy feed on five nights of each week. Following this protocol all patients gained weight (mean weight gain 5.4 kg, range 2–17). For the group as a whole, lung function remained stable during the period of feeding; however a significant correlation between improvement in lung function and weight gain was demonstrated. Hyperglycaemia during feeding in this adult population was common (9/14, 64%) but was easily controlled with insulin therapy.  相似文献   
84.
对107名小儿调查分析其智商及出生体重与成孕日父母生物节律的相关性,获得了有意义的结论:①小儿智商与成孕时父母的智力节律处于高潮期有关,②小儿出生体重与成孕时父母的体力节律处于高潮期有关。本组资料为我们倡导的“先咨询、后受孕”提供了依据,指出选择高潮期妊娠配合孕期保健有助于优生。  相似文献   
85.
Abstract: The Self-Rating Body Image (SRBI) test was used to determine whether the patients with eating disorders such as anorexia nervosa or bulimia showed their body image disturbance or not. The SRBI was completed by 120 subjects who consisted of 30 low weight (LW) controls, 30 normal weight (NW) controls, 30 high weight (HW) controls, 18 anorexic patients (AN) and 12 bulimic patients (BN). The AN group had a significantly greater dissatisfaction with the scales of the body shape, visceral organ and face image of the SRBI than the weight-matched LW group. The BN group had a significantly greater dissatisfaction with the visceral organ image than the weight-matched NW group. However, no significant difference in the body shape and face images between the BN and NW groups was found. Our results suggest that the anorexic patients may disturb more parts of the body image than the bulimic patients though both the anorexic and bulimic patients showed the disturbance of body image.  相似文献   
86.
目的探讨极低出生儿体重儿转运过程中的有效护理措施,降低其死亡率。方法通过转运系统将基层医院32例极低出生体重儿转运至新生儿重症监护病房治疗,具体措施包括现场抢救,应用肺泡表面活性物质,途中连续监护和治疗。结果极低出生体重儿32例均成功转运,治愈出院13例,死亡19例,无一例途中死亡。结论全程监护,尽早转运及应用固尔苏是转运成功及降低极低出生体重儿死亡率的关键。  相似文献   
87.
本文报道人精液抑制素的制备及其生物学特性。收集的新鲜人精液经乙醇沉淀和丙酮冲洗,获得的粗提物经Sephadex G100处理,产生具有高活性抑制素hP2组分。应用hP2测定使去势雄性大鼠增高的血清FSH水平降低。其生物特性:hP2的生物活性按单位重量计算为粗提物的10倍以上,包含16种氨基酸,通过SDS-PAGE计算分子量为11,500道尔顿。  相似文献   
88.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms.  相似文献   
89.
危险管理法在农村儿童保健中应用效果评价   总被引:1,自引:0,他引:1  
在儿保领域应用危险管理法目的是充分利用有限的卫生资源,减轻基层儿保人员负担,提高儿保服务效果和儿童健康水平。通县农村于1990年以来婴幼儿保健中应用危险管理法的研究显示,高危儿健康状况在加强管理后与非高危儿的相近;实验组与对照组儿童在婴幼儿期的死亡及婴幼儿后期生长发育方面差别无统计学意义;儿童满5岁时,两组生长发育水平无显著性差别。提示在我国有限卫生资源基础上,应用危险管理法于儿保领域有重要现实意义。  相似文献   
90.
Fluid overload predisposes chronic hemodialysis patients to cardiovascular disease, a significant cause of morbidity and mortality in these patients. We evaluated the efficacy of monitoring changes in blood volume during routine hemodialysis to detect fluid overload. Intradialytic changes in blood volume were monitored by continuously measuring hematocrit in all 56 patients in a single dialysis unit over 7 weeks. After Week 1, patients were categorized into 2 separate groups depending on their maximum intradialytic decreases in blood volume. In Group 1, 46 of 56 or 82% had greater than a 5% decrease in blood volume while in Group 2, 10 of 56 or 18% had less than a 5% decrease in blood volume. During Weeks 2–7, dialytic fluid removal was intentionally increased in Group 2 patients by 0.80 ± 0.62 L (mean ± SD) or 47 ± 43%. This intervention resulted in a larger (p < 0.02) intradialytic decrease in body weight (2.7 ± 0.9 kg versus 2.0 ± 0.8 kg) and a larger (p < 0.02) intradialytic decrease in blood volume (15 ± 5% versus 4 ± 1%) than experienced during Week 1 with a low incidence of symptoms. We conclude that there is a significant percentage of chronic hemodialysis patients who can tolerate additional fluid removal without hypovolemic symptoms even though they are considered to be at dry weight by routine physical examination and that the identification of these patients can be facilitated by intradialytic blood volume monitoring.  相似文献   
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