全文获取类型
收费全文 | 2828篇 |
免费 | 208篇 |
国内免费 | 21篇 |
学科分类
医药卫生 | 3057篇 |
出版年
2021年 | 26篇 |
2019年 | 30篇 |
2018年 | 40篇 |
2017年 | 28篇 |
2016年 | 33篇 |
2015年 | 32篇 |
2014年 | 44篇 |
2013年 | 72篇 |
2012年 | 116篇 |
2011年 | 119篇 |
2010年 | 72篇 |
2009年 | 51篇 |
2008年 | 86篇 |
2007年 | 108篇 |
2006年 | 95篇 |
2005年 | 87篇 |
2004年 | 105篇 |
2003年 | 91篇 |
2002年 | 81篇 |
2001年 | 95篇 |
2000年 | 119篇 |
1999年 | 93篇 |
1998年 | 43篇 |
1997年 | 35篇 |
1996年 | 29篇 |
1995年 | 31篇 |
1994年 | 35篇 |
1993年 | 32篇 |
1992年 | 87篇 |
1991年 | 88篇 |
1990年 | 57篇 |
1989年 | 67篇 |
1988年 | 63篇 |
1987年 | 64篇 |
1986年 | 68篇 |
1985年 | 55篇 |
1984年 | 38篇 |
1983年 | 44篇 |
1981年 | 28篇 |
1980年 | 24篇 |
1979年 | 38篇 |
1978年 | 26篇 |
1977年 | 33篇 |
1976年 | 23篇 |
1974年 | 24篇 |
1972年 | 21篇 |
1971年 | 22篇 |
1926年 | 23篇 |
1925年 | 28篇 |
1924年 | 22篇 |
排序方式: 共有3057条查询结果,搜索用时 205 毫秒
11.
Macrophage colony-stimulating factor mRNA and protein in atherosclerotic lesions of rabbits and humans. 总被引:20,自引:3,他引:17 下载免费PDF全文
M. E. Rosenfeld S. Yl-Herttuala B. A. Lipton V. A. Ord J. L. Witztum D. Steinberg 《The American journal of pathology》1992,140(2):291-300
In this study, the authors demonstrate the expression of mRNA and the presence of protein for macrophage colony-stimulating factor (MCSF) in atherosclerotic lesions from humans and rabbits. In situ hybridization of serial sections of human fatty streaks demonstrated expression of MCSF mRNA by cells dispersed throughout the lesions. Immunocytochemical staining with a panel of MCSF-specific antibodies showed extensive cell-associated staining of all of the cell types in the lesions. Immunocytochemical studies of atherosclerotic lesions from Watanabe heritable hyperlipidemic (WHHL) and cholesterol-fed rabbits demonstrated a similar cell-associated pattern of staining. There was no MCSF-specific staining of aortas from normal rabbits or of cultured aortic smooth muscle cells from either humans or rabbits. Macrophage-derived foam cells (MFC) were isolated from the aortas of ballooned, cholesterol-fed rabbits. A Northern blot demonstrated that RNA isolated from the MFC hybridized with a human cDNA probe for MCSF. RNA from alveolar macrophages isolated simultaneously from the same rabbits did not hybridize with the MCSF probe. Conditioned media from an 18- to 24-hour incubation of the MFC contained colony-stimulating activity as demonstrated in a mouse bone marrow culture assay. Most of this colony-stimulating activity was neutralized by preincubating the conditioned media with an MCSF-specific antibody. 相似文献
12.
B Zumoff G W Strain L K Miller W Rosner C D Levit E H Miller R S Rosenfeld 《International journal of obesity (2005)》1988,12(6):525-531
Obese men have hyperestrogenemia-induced hypogonadotropic hypogonadism (HHG), due, we believe, to increased rarmatization of adrenal androgens by the increased bulk of aromatase-containing adipose tissue. We studied the effects of corticosuppressive doses of dexamethasone (D) on 24-h mean plasma total and free estradiol (E2), estrone (E1), LH, FSH, total and free testosterone, delta 4-androstenedione (delta 4), and sex-hormone-binding globulin (SHBG) in nine obese men and five normal-weight controls. In the obese men, the following hormones fell: E2 [59 +/- 19 to 39 +/- 11 pg/ml (P less than 0.01)], E1 [93 +/- 41 to 50 +/- 25 pg/ml; (P less than 0.01)], delta 4-androstenedione [120 +/- 80 to 55 +/- 27 ng/dl; (P less than 0.02)]; free E2 [1.6 +/- 0.4 to 1.1 +/- 0.2 pg/ml; (P less than 0.01)], SHBG [12.8 +/- 5.3 to 8.2 +/- 3 nM/l; (P less than 0.04)]. FSH rose from 4.8 +/- 3.2 to 7.6 +/- 4.2 miu/ml (P less than 0.01). LH, total and free testosterone showed no significant change. In the nonobese men, there were decreases in total E2 [(34 +/- 6.8 to 25 +/- 10 pg/ml; P less than 0.04)], SHBG [16.8 +/- 7.5 to 10.4 +/- 2.0 nM/l: P less than .05.], free E2 [0.9 +/- 0.2 to 0.7 +/- 0.3 pg/ml: P less than 0.05], delta 4 [91.4 +/- 3.6 to 33.4 +/- 16.7 ng/dl; P less than .01] and total T [492 +/- 44 to 393 +/- 121 ng/dl; P less than 0.04]. There was no significant change in E1, FSH, LH or free T.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
13.
Jonas T. Johnson MD Editor John K. Niparko MD Editor-in-Chief Paul A. Levine MD Editor David W. Kennedy MD Editor Pete Weber MD Editor-in-Chief Randal S. Weber MD Editor Michael S. Benninger MD Past Editor in Chief Richard M. Rosenfeld MD MPH Editor in Chief Robert J. Ruben MD Editor in Chief Richard J.H. Smith MD Editor in Chief Robert Thayer Sataloff MD DMA Editor in Chief Neil Weir MA FRCS Editor Emeritus 《Otolaryngology--head and neck surgery》2006,135(6):829-830
14.
15.
C S Rosenfeld H E Tedrow R Bryan K F Mangan R K Shadduck 《Experimental hematology》1988,16(8):702-704
Large volumes of bone marrow may be required for certain types of autologous bone marrow transplants. The present study was done to determine whether red cells obtained during a bone marrow harvest would be useful in reducing homologous transfusion requirements. A group of patients receiving standard transfusion support during the harvest (group 1) was compared to a group that received processed bone marrow red cells (PBMRBC) (group 2). Using the Cobe 2991 cell processor, 90% of the harvested bone marrow red cells were extracted and transfused during the procedure. Group 2 received a median of 1500 ml of blood processed from the bone marrow or 413 ml (volume of marrow processed x hematocrit) of red cells. Infusion of the PBMRBC reduced the homologous transfusion requirement from 6.5 units to 3.0 units (p = 0.02). In addition, group 1 had a 20% decrease in hematocrit following transfusion compared to the pre-harvest hematocrit, as opposed to an 8% decrease in group 2 (p = 0.02). This study indicates that PBMRBC can reduce the homologous transfusion requirements during an autologous bone marrow harvest. 相似文献
16.
17.
18.
E M Grace J M Rosenfeld G D Sweeney W W Buchanan 《Current medical research and opinion》1987,10(9):580-591
Nineteen patients, aged 60 years and over, with rheumatoid arthritis participated in a clinical trial to investigate the pharmacokinetics of isoxicam (a new non-steroidal anti-inflammatory drug) in this age group. The purpose of the study was to determine if the pharmacokinetics are different compared to a younger healthy population. The half-lives were independent of dosage, indicating linearity of pharmacokinetics. Furthermore, the half-lives after repeated dosing were not different from those found after single doses of 400 mg. This shows that there is neither undue accumulation of the drug nor induction of its own metabolism. These results are similar to the results obtained in other centres when isoxicam was administered to healthy subjects between 18 and 32 years. 相似文献
19.
A Erman J Winkler B Chen-Gal M Rabinov A Zelykovski S Tadjer J Shmueli E Levi A Akbary J B Rosenfeld 《Journal of hypertension》1991,9(11):1057-1062
Studies in animal models have indicated that ramipril is a potent inhibitor of angiotensin converting enzyme (ACE) in serum and tissue. In our study, the normal range of ACE activity and the inhibitory effect of short-term oral administration of ramipril on ACE activity in human serum and tissue samples of renal cortex, heart and blood vessels were determined. ACE activity in the renal cortex (125.2 +/- 11.5 nmol/mg per min) was greater than 600 times that of the heart (0.20 +/- 0.01 nmol/mg per min), greater than 500 times that of the veins (0.23 +/- 0.09 nmol/mg per min) and greater than 150 times that of the arteries (0.80 +/- 0.23 nmol/mg per min). ACE activity in the renal cortex and arteries 2 h after last dosing was almost completely inhibited by ramipril whereas ACE activity in the veins and heart was inhibited to a lesser extent. Our results demonstrate in man, for the first time, an inhibition of tissue ACE following short-term oral treatment with an ACE inhibitor. 相似文献
20.
Interobserver variability in neonatal cranial ultrasonography 总被引:1,自引:0,他引:1
Jennifer Pinto Nigel Paneth Elias Kazam Ram Kairam Sylvan Wallenstein Walter Rose David Rosenfeld Steven Schonfeld Irving Stein Thomas Witomski 《Paediatric and perinatal epidemiology》1988,2(1):43-58
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study. 相似文献