全文获取类型
收费全文 | 27833篇 |
免费 | 1694篇 |
国内免费 | 362篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 600篇 |
妇产科学 | 7017篇 |
基础医学 | 3072篇 |
口腔科学 | 190篇 |
临床医学 | 2990篇 |
内科学 | 2057篇 |
皮肤病学 | 244篇 |
神经病学 | 499篇 |
特种医学 | 342篇 |
外国民族医学 | 2篇 |
外科学 | 1041篇 |
综合类 | 4704篇 |
现状与发展 | 3篇 |
一般理论 | 4篇 |
预防医学 | 4026篇 |
眼科学 | 68篇 |
药学 | 2240篇 |
43篇 | |
中国医学 | 462篇 |
肿瘤学 | 261篇 |
出版年
2024年 | 62篇 |
2023年 | 383篇 |
2022年 | 760篇 |
2021年 | 1118篇 |
2020年 | 1007篇 |
2019年 | 1008篇 |
2018年 | 907篇 |
2017年 | 1088篇 |
2016年 | 1227篇 |
2015年 | 1032篇 |
2014年 | 1786篇 |
2013年 | 2605篇 |
2012年 | 1499篇 |
2011年 | 1801篇 |
2010年 | 1452篇 |
2009年 | 1255篇 |
2008年 | 1230篇 |
2007年 | 1183篇 |
2006年 | 1199篇 |
2005年 | 974篇 |
2004年 | 906篇 |
2003年 | 726篇 |
2002年 | 544篇 |
2001年 | 501篇 |
2000年 | 410篇 |
1999年 | 386篇 |
1998年 | 286篇 |
1997年 | 265篇 |
1996年 | 254篇 |
1995年 | 295篇 |
1994年 | 192篇 |
1993年 | 170篇 |
1992年 | 135篇 |
1991年 | 127篇 |
1990年 | 120篇 |
1989年 | 107篇 |
1988年 | 111篇 |
1987年 | 74篇 |
1986年 | 68篇 |
1985年 | 125篇 |
1984年 | 93篇 |
1983年 | 78篇 |
1982年 | 73篇 |
1981年 | 45篇 |
1980年 | 59篇 |
1979年 | 45篇 |
1978年 | 31篇 |
1977年 | 22篇 |
1976年 | 21篇 |
1973年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
M. Bonati R. Bortolus F. Marchetti M. Romero G. Tognoni 《European journal of clinical pharmacology》1990,38(4):325-328
Summary The need for further information on drug utilization patterns during pregnancy in different countries was assessed by reviewing literature obtained by hand and computer searches for the years 1960–1988.The 13 identified studies showed that pregnant women used an average of 4.7 drugs. The most commonly ingested medications were vitamins and iron preparations (almost all women), analgesics, antiemetics and antacids.However, the important variables taken into account differently in each study, such as date of surveillance, country, size of population, personal habits, and physiopathological and demographic characteristics, may it impossible to construct a comprehensive, detailed, up-to-date picture of drug utilization during pregnancy.The evaluation confirmed the need for systematic permanent surveillance of drug utilization in pregnancy, so as to avoid the use of data based on widely differing contexts, times and methods, in a field where knowledge is often derived from scanty information.This study was supported in part by the National Research Council (CNR, Rome, Italy), Convenzione Farmacologia Clinica 相似文献
93.
妊娠期雌二醇和催乳素与瘦素的关系 总被引:2,自引:0,他引:2
目的 研究妊娠期间性激素与瘦素水平之间的关系。方法 在180例不同孕周的妇女中,按孕周分为<20周组,20-23周组,≥28周组,采用酶联免疫吸附法测定其外周血血清雌二醇(E2)和催乳素(PRL),放射免疫法测定血清瘦素水平,分析这些激素之间的相互关系。结果 E2和PRL均随妊娠进展而逐步升高(P<0.0001),组间均有显著差异(P<0.05)。各组瘦素水平均高于非妊娠组,但组间差异无显著性。瘦素水平与孕妇体重及体重指数显著相关(P0.01),与PRL也呈相关(P<0.05),而与E2无明显相关。结论 PRL水平与妊娠期瘦素水平升高有一定关系。 相似文献
94.
95.
Bengtsson G.; Wallin A.; Sjoblom P.; Lindblom B. 《Human reproduction (Oxford, England)》1995,10(2):459-463
The objective of this study was to assess the ability of certaindrugs, used for local injection therapy of ectopic pregnancy,to suppress the activities of cultured human placental cells.Placental cells from legal first trimester abortions were preparedby collagenase treatment and density gradient centrifugation.The cells were exposed to hyperosmolar glucose (500 mg/ml),15-methyl-prostaglandin-F2 (15-m-PGF2; 107 to 103mol/l) and prostaglandin-F2 (PGF2; 105 to 5X103mol/l) for 30 min on days 24 after seeding. The effectson the secretion of human chorionic gonadotrophin (HCG) andprogesterone, as well as on the protein content per culturewell, were measured. Hyperosmolar glucose was the most effectivedrug and caused a marked decrease of the protein content inthe culture wells and a reduction of progesterone secretion.Of the two prostaglandins, only 15-m-PGF2 affected the viabilityof the cells and reduced the protein content of the wells. Theclinical effectiveness of the two groups of drugs seems to besimilar but certain in-vitro effects are different. Thus invivo they may act on different target tissues. Against thisbackground, the combination of hyperosmolar glucose and prostaglandinsmight be an interesting approach for local injection therapyfor tubal pregnancy. 相似文献
96.
Friedman D Cuneo S Valenzano M Marinari GM Adami GF Gianetta E Traverso E Scopinaro N 《Obesity surgery》1995,5(3):308-313
Background: 239 pregnancies occurred in 1136 women who had undergone biliopancreatic diversion (BPD). Methods: There were
73 abortions, and 14 pregnancies are presently in their course. The 152 term pregnancies (six twins) occurred in 129 women
2-173 months (mean 42.7) after BPD. Mean age and current excess weight were 31.4 years (20-42) and 29.1% (-6.9-78.2), and
mean excess weight loss was 72.9% (30.4-110.5). Results: Mean weight gain during pregnancy was 6.2 kg (-21-25). In 32 patients
(21%), parenteral nutritional support was needed. In all the other patients (79%), the usual supplementations were given.
Of the newborns, 122 were delivered at term (84.7%) with a mean weight of 2842.4 g (1760-4600 g) and a mean length of 48.5
cm (43-59 cm), while the 22 preterm babies (15.3%) weighed 2151.1 g (1400-3850 g) and had a length of 44.6 cm (33-56 cm).
Forty infants (27.8%) were small for gestational age but 17 of them weighed more than 2500 g. Eleven twins (one abortion at
26th week) were also delivered, with a mean weight of 2088.6 g (1200-3100 g) and a mean length of 45.6 cm (35-50 cm). Delivery
was spontaneous in 85 instances (56%), while vacuum extractor was used in one, and 66 cesarean sections were performed. There
were two birth malformations, one infant died after surgery for meconium obstruction and two died from unknown causes. Of
the 129 women, 35 had been infertile before BPD. Conclusions: Disappearance of infertility and decrease of pregnancy risk
are to be considered among the beneficial effects of weight reduction following BPD. 相似文献
97.
本文对104例过期妊娠与同期2571例足月妊娠的并发症及分娩方式进行了比较分析,结果表明:过期妊娠中头盆不称、胎位异常、胎儿宫内窘迫、巨大儿等发生率明显高于足月妊娠,且剖宫产率也较高,故认为适时终止妊娠对减少过期妊娠的发生至关重要。 相似文献
98.
Delivery of a normal newborn after intensive medical treatment for an acute exacerbation of ulcerative colitis during pregnancy: A case report 总被引:1,自引:0,他引:1
(Received for publication on Sept. 21, 1998; accepted on May 27, 1999) 相似文献
99.
Two idiopathic thrombi loosely attached to the left ventricular wall were detected by dynamic three-dimensional echocardiography. Because the thrombi were shown to be lobulated and extremly mobile, urgent surgical treatment was mandatory. Three-dimensional image reconstruction enhanced appreciation of left ventricular thrombi by enabling accurate imaging of the spatial relationship between the thrombus, the myocardial wall, and the valvular apparatus, so that the most advantageous surgical access could be chosen. 相似文献
100.
Laparoscopic cholecystectomy in pregnancy 总被引:4,自引:1,他引:3
Background: Laparoscopic cholecystectomy is now the standard treatment for symptomatic gallstones; while symptomatic gallstones during pregnancy are not frequent they are by no means rare. The role of laparoscopic cholecystectomy during pregnancy is controversial but initial reports suggest it is both safe and feasible.
Methods: During a consecutive series of 500 laparoscopic cholecystectomies, 3 patients have undergone laparoscopic cholecystectomy during pregnancy. The 3 patients were 16–27 weeks pregnant with an average age of 32 years. The indication for laparoscopic cholecystectomy was severe pain in two patients and gallstone pancreatitis in one patient. Following standard obstetric anesthesia, laparoscopic cholecystectomy was performed. Open cannulation was used to establish peritoneal access, following which standard, four-port laparoscopic cholecystectomy was performed without complication. The insufflation pressure used was 8–10 mmHg CO2 and a liver retractor was employed to facilitate access.
Results: In each case the postoperative recovery was rapid and uneventful for both mother and fetus. The patients were discharged on the first or second postoperative day.
Conclusions: Laparoscopic cholecystectomy during the second trimester of pregnancy is both safe and feasible provided both suitable surgical and anesthetic expertise are available. Even up to the end of the second trimester there is sufficient access for the technique to be employed. 相似文献