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   319篇
  免费   26篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   18篇
妇产科学   10篇
基础医学   47篇
口腔科学   1篇
临床医学   46篇
内科学   63篇
皮肤病学   1篇
神经病学   14篇
特种医学   37篇
外科学   18篇
综合类   22篇
预防医学   30篇
眼科学   2篇
药学   18篇
肿瘤学   17篇
  2021年   2篇
  2020年   2篇
  2019年   2篇
  2018年   6篇
  2016年   4篇
  2015年   9篇
  2014年   7篇
  2013年   8篇
  2012年   6篇
  2011年   3篇
  2010年   14篇
  2009年   9篇
  2008年   3篇
  2007年   9篇
  2006年   14篇
  2005年   6篇
  2004年   7篇
  2003年   7篇
  2002年   6篇
  2001年   4篇
  2000年   2篇
  1999年   9篇
  1998年   19篇
  1997年   22篇
  1996年   15篇
  1995年   15篇
  1994年   13篇
  1993年   9篇
  1992年   3篇
  1991年   13篇
  1990年   14篇
  1989年   8篇
  1988年   7篇
  1987年   6篇
  1986年   8篇
  1985年   3篇
  1984年   8篇
  1983年   5篇
  1982年   5篇
  1981年   2篇
  1980年   2篇
  1977年   2篇
  1975年   2篇
  1971年   2篇
  1966年   2篇
  1962年   2篇
  1946年   2篇
  1944年   3篇
  1941年   2篇
  1938年   2篇
排序方式: 共有346条查询结果,搜索用时 15 毫秒
1.
1. The pharmacokinetics of Dalal-peptide T-NH2 (peptide T) was determined during phase I clinical trials in patients with acquired immunodeficiecy disease (AIDS) and AIDS related complex (ARC). Drug levels were determined by specific RIA, and in some cases with HPLC analysis, after intraveneous (i.v.) or intranasal (i.n.), via metered sprayer, administration.

2. The plasma kinetics appeared to be bi-phasic with a first compartment half-life of 30 to 60 minutes and a second plasma clearence rate of 4 to 6 hours, observed for both routes of administration. Peptide T, in one individual was confirmed to be present at 6 hrs in plasma, determined after HPLC isolation followed by specific RIA.

3. Bioavailabilty, determined for a 2 mg test dose in six individuals was 9.3 ± 6.9 nmol/L. Peak plasma levels of 41 ± 30 nmol/L after 10 mg i.n., 2.8 ± 5.9 nmol/L after 2mg i.n., and 0.13 ± 0.07 nmol/L after 0.4 mg i.n. were observed. In two individuals tested, peptide T was detected in CSF at levels 20% of the corresponding plasma level 90 and 145 minutes post i.v. administration. Peptide T was not detected in urine. I.N. administration was well tolerated for times up to 21 months.  相似文献   

2.
3.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
4.
5.
6.
The cost of 2 g ampicillin/1 g sulbactam given IV piggyback qid was compared with 900 mg clindamycin admixed with 1.5 mg/kg gentamicin given IV piggyback tid for the treatment of perforated or gangrenous appendicitis in 116 patients. Fifty-eight ampicillin/sulbactam-receiving patients incurred greater costs for IV supplies (+104.6/patient vs +67.9/patient) and nursing administration costs (+16.5/patient vs +10.7/patient). On the other hand, pharmacist and technician preparation costs were greater for the 58 clindamycin/gentamicin-receiving patients (+15.4/patient vs +13.3/patient). The clindamycin/gentamicin-receiving patients also incurred additional changes for laboratory fees and pharmacokinetic monitoring--+18.7/patient and +36.1/patient, respectively. When incorporating all cost parameters, there were no statistically significant differences in mean total drug therapy costs between the two treatment regimens--+433.3 +/- +58.5/patient for ampicillin/sulbactam and +373.8 +/- +86.2/patient for clindamycin/gentamicin.  相似文献   
7.
A total of 651 cases of leprosy were hospitalised from Jan 1987 to Dec 1992. Each patient underwent haemogram, total and differential white cell count, urinalysis, liver function tests, skin slit smear for AFB and skin biopsy. Nerve conduction studies, electomyographic studies and nerve/nerve sheath biopsies were undertaken as and when indicated. These patients were managed with multidrug therapy. Paucibacillary (PB) leprosy accounted for 476 (73.1%) cases which comprised of indeterminate leprosy 90 (13.8%), tuberculoid leprosy 14 (2.2%), borderline tuberculoid leprosy 310 (47.6%) and neuritic leprosy 62 (9.5%). The remaining 175 patients (26.9%) were multibacillary (MB) which included borderline leprosy 9 (1.4%), borderline lepromatous leprosy 129 (19.8%) and lepromatous leprosy 37 (5.7%) patients. There were total 153 patients in 1987. This number declined to 44 in 1992. PB declined from 113 in 1987 to 39 in 1992 and MB cases from 40 to 5.KEY WORDS: Leprosy  相似文献   
8.
Eleven HIV-1 seronegative subjects previously injected with an HIV-1 p17 synthetic peptide vaccine (HGP-30) were given two booster immunizations to evaluate memory cell responses and the ability to boost cellular and humoral immune responses. Five of 11 subjects showed a significant increase in their antibody titres to HGP-30 or p17 and 6/11 had T-cell proliferation responses to either HGP-30 or p17. HIV-1 virus challenge studies in SCID mice demonstrated that 39 of 50 mice (78%) receiving PBMC from 5 of the HGP-30 immunized subjects were protected from infection with a different strain of HIV-1 compared to 4 of 30 mice (13%) that received PBMC from 3 non-immunized subjects (p < 0.001). These studies show that booster immunizations with HGP-30 vaccine are safe and non-toxic and induce protective cell mediated immune responses.  相似文献   
9.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph.  相似文献   
10.
Fong  LY; Farber  JL; Magee  PN 《Carcinogenesis》1998,19(9):1591-1596
Previous work has shown that sustained increased and decreased cell proliferation, induced by dietary zinc deficiency and caloric restriction respectively, influence the course of N- nitrosomethylbenzylamine (NMBA)-induced esophageal carcinogenesis in rats. The present study considered whether the increased cell proliferation and esophageal tumor incidence induced by zinc deficiency are reversed upon zinc replenishment. Weanling rats were maintained initially on a deficient diet containing 4 p.p.m. zinc. After 5 weeks, carcinogen-treated animals were given six intragastric doses of NMBA (2 mg/kg twice weekly). Controls were untreated. After the second NMBA dose, the rats were divided into three dietary groups. One group was continued on the deficient diet, while the other two groups were switched to diets containing either 75 or 200 p.p.m. zinc, with half of the members in each group fed ad libitum and half pair-fed with deficient rats. NMBA-untreated controls were similarly replenished. At various time points, esophageal cell proliferation was assessed in five animals from each group by immunohistochemical detection of cells in S phase, with in vivo 5-bromo-2'deoxyuridine labeling. At 11 weeks after the first dose, esophageal tumor incidence was greatly reduced, from 100% in the deficient group to 26 and 14% respectively in the replenished groups fed ad libitum 75 and 200 p.p.m. zinc and to 14 and 11% respectively in the replenished groups pair-fed 75 and 200 p.p.m. zinc. In addition, the number of tumors per esophagus was reduced from 9.93 +/- 4.25 in deficient rats, to a range of 0.11 +/- 0.31-0.30 +/- 0.54 in replenished animals. Following zinc replenishment, esophageal cell proliferation, as measured by labeling index (LI), the number of labeled cells and the total number of cells, was markedly decreased in NMBA-untreated and -treated esophagi as compared with those in corresponding deficient esophagi. Thus, the esophageal cell proliferation induced by zinc deficiency is reversed by zinc replenishment and replenished animals have a markedly lower incidence of esophageal tumors.   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