全文获取类型
收费全文 | 705篇 |
免费 | 78篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 36篇 |
妇产科学 | 6篇 |
基础医学 | 80篇 |
口腔科学 | 33篇 |
临床医学 | 67篇 |
内科学 | 171篇 |
皮肤病学 | 22篇 |
神经病学 | 22篇 |
特种医学 | 134篇 |
外科学 | 47篇 |
综合类 | 81篇 |
预防医学 | 22篇 |
药学 | 39篇 |
1篇 | |
肿瘤学 | 28篇 |
出版年
2021年 | 3篇 |
2019年 | 5篇 |
2018年 | 12篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 14篇 |
2014年 | 17篇 |
2013年 | 16篇 |
2012年 | 12篇 |
2011年 | 12篇 |
2010年 | 21篇 |
2009年 | 28篇 |
2008年 | 14篇 |
2007年 | 15篇 |
2006年 | 34篇 |
2005年 | 9篇 |
2004年 | 12篇 |
2003年 | 21篇 |
2002年 | 14篇 |
2001年 | 16篇 |
2000年 | 10篇 |
1999年 | 8篇 |
1998年 | 31篇 |
1997年 | 51篇 |
1996年 | 46篇 |
1995年 | 34篇 |
1994年 | 34篇 |
1993年 | 36篇 |
1992年 | 22篇 |
1991年 | 12篇 |
1990年 | 16篇 |
1989年 | 14篇 |
1988年 | 18篇 |
1987年 | 11篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 11篇 |
1983年 | 13篇 |
1982年 | 17篇 |
1981年 | 16篇 |
1980年 | 11篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 20篇 |
1975年 | 10篇 |
1974年 | 3篇 |
1971年 | 2篇 |
1967年 | 2篇 |
1965年 | 2篇 |
排序方式: 共有790条查询结果,搜索用时 0 毫秒
11.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
12.
MJ Stevens PD Stricker J Saalfeld PC Brenner R Kooner GFA O'Neill PJ Duval RS Jagavkar P Cross J Martland 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):152-160
Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability. 相似文献
13.
几种中西药抗人实验模拟运动病效果观察 总被引:1,自引:0,他引:1
目的 :选用中药“治晕灵”的主要成分生姜、明天麻等六味草药煎成汤剂、或半量汤剂配西药脑益嗪、山莨菪碱各1 4临床常用量配成复方中西药制剂 ,与目前常用抗晕药晕海宁等中、西药的药效进行比较 ,看中药制剂或中西药复方制剂是否具有较好的抗运动病效果。方法 :选 7名敏感被试者 (女性 ,19~ 2 1岁 ) ,用旋转刺激诱发运动病至出现恶心。按拉丁方设计 ,与安慰剂 (淀粉 10 0mg)及晕海宁 (5 0mg)进行对比 ,分别观察了生姜合剂 (30ml)、晕可平 (30ml)、山莨菪碱 (10mg)、脑益嗪 (2 5mg)及上述复方中西药制剂口服后的运动病耐力。结果 :与安慰剂比较 ,晕海宁、山莨菪碱、脑益嗪、晕可平、生姜合剂、复方中西药制剂分别使运动病耐力提高 5 .4%、7.5 %、5 .9%、7.4%、32 .3 %、2 0 .4% ;生姜合剂效果较优 ,除口服时有辛辣味外 ,无明显的副作用。复方中西药制剂各成分未显示协同作用 ,而只是简单的作用相加。结论 :生姜合剂具有较好的抗运动病作用 相似文献
14.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
15.
16.
17.
18.
19.
Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
20.
Enzymatic deacylation of the lipid A moiety of Salmonella typhimurium lipopolysaccharides by human neutrophils. 总被引:18,自引:0,他引:18 下载免费PDF全文
C L Hall R S Munford 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(21):6671-6675
Lipid A, the toxic moiety of Gram-negative bacterial lipopolysaccharides (endotoxins), is a glucosamine disaccharide to which fatty acid and phosphate residues are covalently attached. Recent studies of Salmonella lipid A indicate that 3-hydroxytetradecanoic acid (3-OH-14:0) residues are directly linked to the glucosamine backbone and the nonhydroxylated fatty acids (principally dodecanoic and tetradecanoic acids) are esterified to the hydroxyl groups of some of the 3-OH-14:0 molecules. We report here that the granule fraction of human neutrophils contains one or more enzymes that partially deacylate Salmonella typhimurium lipid A by removing the nonhydroxylated fatty acids, leaving almost all of the 3-OH-14:0 residues linked to glucosamine. The available evidence suggests that similar reactions also occur in living neutrophils that ingest lipopolysaccharides by antibody-dependent phagocytosis. 相似文献