全文获取类型
收费全文 | 3510篇 |
免费 | 279篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 160篇 |
妇产科学 | 115篇 |
基础医学 | 354篇 |
口腔科学 | 72篇 |
临床医学 | 360篇 |
内科学 | 837篇 |
皮肤病学 | 33篇 |
神经病学 | 269篇 |
特种医学 | 137篇 |
外国民族医学 | 1篇 |
外科学 | 450篇 |
综合类 | 66篇 |
一般理论 | 1篇 |
预防医学 | 418篇 |
眼科学 | 12篇 |
药学 | 192篇 |
2篇 | |
中国医学 | 1篇 |
肿瘤学 | 301篇 |
出版年
2021年 | 38篇 |
2020年 | 27篇 |
2019年 | 46篇 |
2018年 | 54篇 |
2017年 | 36篇 |
2016年 | 37篇 |
2015年 | 34篇 |
2014年 | 84篇 |
2013年 | 115篇 |
2012年 | 179篇 |
2011年 | 164篇 |
2010年 | 104篇 |
2009年 | 94篇 |
2008年 | 135篇 |
2007年 | 180篇 |
2006年 | 183篇 |
2005年 | 166篇 |
2004年 | 146篇 |
2003年 | 139篇 |
2002年 | 115篇 |
2001年 | 103篇 |
2000年 | 121篇 |
1999年 | 105篇 |
1998年 | 51篇 |
1997年 | 45篇 |
1996年 | 43篇 |
1995年 | 40篇 |
1994年 | 32篇 |
1992年 | 74篇 |
1991年 | 75篇 |
1990年 | 60篇 |
1989年 | 56篇 |
1988年 | 63篇 |
1987年 | 48篇 |
1986年 | 49篇 |
1985年 | 39篇 |
1984年 | 51篇 |
1983年 | 34篇 |
1980年 | 34篇 |
1979年 | 31篇 |
1978年 | 43篇 |
1974年 | 44篇 |
1973年 | 30篇 |
1972年 | 31篇 |
1971年 | 27篇 |
1970年 | 48篇 |
1969年 | 33篇 |
1968年 | 34篇 |
1967年 | 31篇 |
1966年 | 34篇 |
排序方式: 共有3797条查询结果,搜索用时 15 毫秒
1.
2.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
3.
The effect of diaper type and overclothing on fecal contamination in day-care centers 总被引:2,自引:0,他引:2
Fecal coliform contamination of environmental surfaces and hands in the day-care center is common. This study evaluated the effect of two diaper types on fecal contamination. Ten rooms in four day-care centers containing 141 children were studied in a prospective, randomized, crossover study. A total of 2946 samples were cultured during the 9-week study. Fecal coliforms were isolated from 307 inanimate objects (15%), 73 toy balls (46%), and 131 hands (17%). The number of contaminated inanimate objects was significantly less in rooms where paper diapers were worn when compared with that in rooms where double cloth diapers with plastic overpants were worn and in rooms where clothes were worn over diapers. Inanimate object cultures had more contamination in rooms in which diarrhea had occurred. Containment of feces by overclothes and diaper type may be important in decreasing transmission of enteric pathogens in day-care environments. 相似文献
4.
F M Muggia E LePoidevin S Jeffers C Russell W Boswell C P Morrow J Curtin J Schlaerth 《Annals of oncology》1992,3(2):149-154
Nineteen patients with ovarian cancer and minimal residual or persistent disease who were treated with cisplatin or carboplatin-based intraperitoneal (IP) regimens had distribution studies of IP contrast and computerized tomography prior to and during treatment. The distribution pattern was assessed retrospectively and scored for the presence of contrast in each of eight regions: the under surface of right and left diaphragms, the right and left paracolic gutters, the lesser omental sac, the intramesenteric region and the true and false pelvis. Assigning a point to each region with adequate distribution, we classified 10 patients to an excellent pattern (greater than or equal to 7 of 8 regions), 6 to a good pattern (5 to less than 7 regions), and 3 to an inadequate distribution pattern (less than 5 regions). Serial studies were performed in 8 patients after more than 4 cycles of IP therapy. In these patients, all of whom were tolerating treatment without progression, the distribution remained virtually unchanged for those with excellent distribution. One of three with good distribution manifested inadequate distribution on repeat study, and one of two with inadequate distribution improved to show a good pattern. In this small study there was no correlation of distribution patterns with plasma CA-125 at onset of IP treatment and prior surgical procedures or placement of the catheter tip. However, three patients with unsatisfactory patterns had procedures consisting of catheter placement only rather than formal reassessment laparotomies for ovarian cancer. Since satisfactory IP distribution may be required for obtaining a therapeutic advantage from IP therapy, methods for its assessment must be developed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
6.
To establish a reference range, we measured intact parathyrin (parathyroid hormone, PTH) in 245 healthy postmenopausal women, ages 42-75 years, with use of the Allegro Intact PTH Kit from Nichols Institute Diagnostics. We also assayed serum from a subset of 120 of the women with kits specific for mid-molecule PTH. The mean intact PTH concentration for the 245 women was 32 ng/L (95% confidence interval 14-60 ng/L). Intact PTH values in these subjects were not normally distributed, although calcium concentrations in the same samples were. There was positive, but not significant (r = 0.12, P = 0.06), correlation between intact PTH and age, and a significant negative correlation between serum calcium and intact PTH that was not observed between calcium and mid-molecule PTH. The improved sensitivity of the intact PTH assay makes it useful in studies of calcium homeostasis in the normal population. 相似文献
7.
J D Morrow 《The American journal of the medical sciences》1992,303(1):35-39
There are currently six cephalosporins available in the United States for oral use. These agents possess a wide spectrum of activity, are relatively safe to use, and are effective for certain infections involving the respiratory tract, skin, and urinary tract. Nonetheless, in general, they offer no advantage over other classes of antimicrobial drugs and are far more expensive. As a result, the oral cephalosporins are not agents of first choice for the treatment of infection but should be reserved for use as alternative therapy. 相似文献
8.
9.
The rate of clearance of inhaled 99mTc-pentetate aerosols has been used as an indicator of pulmonary epithelial "permeability" in human and animal studies. In order to evaluate this technique further, groups of eight male ferrets (Mustela putorius furo) were given acute exposures to aerosols of CdCl2 or NaCl via endotracheal tube. Serial evaluations of the thoracic clearance rate of inhaled 99mTc-pentetate aerosols (MMAD = 0.6 microns, sigma g = 1.6) were made before exposure and at fixed time points after toxicant exposure (3 or 6, 24, 48 h, and 5 days after CdCl2). These serial evaluations of 99mTc-pentetate thoracic clearance were conducted at three cadmium intake levels (3, 10, and 30 min exposure to 10 mg/m3 CdCl2) in order to evaluate possible dose-related response relationships. The rate of thoracic clearance of Tc-pentetate was observed to be slowed at 3 h after exposure to CdCl2 aerosol and subsequently increased to well above control rates. The time sequence observed strongly suggests that increased Tc-pentetate clearance rates are indicative of a tissue response or repair process, rather than acute lung injury. Tracheal epithelial penetration of macromolecular tracers was not observed to increase in histological evaluations following serial sacrifice. 相似文献
10.
The reactivity of vesicular stomatitis virus (VSV) with kethoxal can be appreciably altered by treatment with 1-guanyl-3, 5-dimethyl pyrazole nitrate (GDMP) and proteolytic enzymes. Pretreatment of purified VSV with GDMP or proteolytic enzymes markedly reduced the effectiveness of kethoxal as a virucide. The rate of neutralizability of GDMP- and trypsin-treated viruses by specific antiserum differed from that of controls. 相似文献