全文获取类型
收费全文 | 575篇 |
免费 | 24篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 16篇 |
妇产科学 | 102篇 |
基础医学 | 21篇 |
口腔科学 | 15篇 |
临床医学 | 119篇 |
内科学 | 50篇 |
皮肤病学 | 5篇 |
神经病学 | 34篇 |
特种医学 | 30篇 |
外科学 | 33篇 |
综合类 | 40篇 |
预防医学 | 47篇 |
眼科学 | 4篇 |
药学 | 41篇 |
中国医学 | 31篇 |
肿瘤学 | 19篇 |
出版年
2022年 | 6篇 |
2021年 | 23篇 |
2020年 | 9篇 |
2019年 | 14篇 |
2018年 | 17篇 |
2017年 | 18篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 28篇 |
2012年 | 30篇 |
2011年 | 20篇 |
2010年 | 16篇 |
2009年 | 16篇 |
2008年 | 25篇 |
2007年 | 20篇 |
2006年 | 17篇 |
2005年 | 24篇 |
2004年 | 13篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 18篇 |
2000年 | 10篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1992年 | 15篇 |
1991年 | 13篇 |
1990年 | 18篇 |
1989年 | 15篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 14篇 |
1985年 | 15篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 9篇 |
1975年 | 5篇 |
1974年 | 7篇 |
1973年 | 11篇 |
1972年 | 8篇 |
1969年 | 5篇 |
1966年 | 5篇 |
1959年 | 3篇 |
1958年 | 6篇 |
1957年 | 5篇 |
排序方式: 共有610条查询结果,搜索用时 15 毫秒
1.
JA HYEON KU CHEOL KWAK SEUNG-JUNE OH EUNSIK LEE SANG EUN LEE JAE-SEUNG PAICK 《International journal of urology》2004,11(7):489-493
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population. 相似文献
2.
Dr. E. Mietzsch M. Koch M. Schaldach J. Werner B. Bellenberg K. U. Wentz 《Medical & biological engineering & computing》1998,36(6):673-678
The application of spin-echo magnetic resonance imaging sequences on non-invasive temperature imaging for temperature mapping
of human limbs is investigated. In an in vitro expriment performed on a meat sample, the equilibrium magnetisation P and the
spin-lattice relaxation time T1 are calculated from the values for the repetition time TR and the signal intensities obtained by a spin-echo sequence at
different tissue temperatures tures as measured by a fibre-optic probe. T1 is linearly correlated to the tissue temperature, and P is linearly correlated to the reciprocal value of the absolute temperature.
Both effects, taken together, lead to a non-linear dependency of the signal intensity on temperature. Therefore a TR leading
to maximum temperature dependency of the signal intensity is calculated and used in the futher experiments. In the in vivo
experiments, the lower legs of two volunteers are cooled from outside. Images are acquired with a spin-echo sequence (1.5T,
TR=1200 ms, TE=10 ms). A rise in signal intensity in the muscle with falling skin temperature is observed, particularly in
more peripheral muscle layers. This study shows that spin-echo sequences can be used to monitor temperature changes and temperature
differences in living muscle tissue. 相似文献
3.
4.
5.
Delayed Enhancement of Acetaminophen Hepatotoxicity by GeneralAnesthesia Using Diethyl Ether or Halothane. WELLS, P. G., RAMJI,P., AND KU, M. S. W. (1986). Fundam. App. Toxicol 6, 299306.Acetaminophen (Tylenol) is a widely used analgesic/antipyreticdrug which is enzymatically bioactivated, or toxified, by thecytochromes P-450 to a hepatotoxic reactive intermediary metabolite.Brief general anesthesia with diethyl ether has been shown toinhibit both the toxifying cytochromes P-450 and enzymatic glucuronidation,the latter constituting up to 60% of acetaminophen eliminationvia a nontoxifying pathway. Thus ether potentially could producea temporally differentiated inhibition of bioactivating and"detoxifying" pathways, resulting in an enhancement of acetaminophenhepatotoxicity if the balance favored bioactivation. To evaluatethis possibility, separate groups of male NIH strain mice weretreated with acetaminophen at different times after 5 min ofanesthesia with ether. Ether produced a 40-fold enhancementin acetaminophen hepatotoxicity as determined by plasma glutamic-pyruvictransaminase (GPT) concentrations. This toxicologic enhancementwas observed only if acetaminophen administration was delayed,with a maximal enhancement when acetaminophen was given 6 hrafter ether, and no effect with a delay of 16 hr. Similar studiesin male CD-1 mice were carried out using halothane (Fluothane)as the general anesthetic given either over 5 min or over 1hr. While halothane given over 5 min had no effect, a 1 hr anestheticduration produced a 10-fold increase in acetaminophen hepatotoxicityas determined by peak GPT concentration, with no observed hepatotoxicityin the halothane controls. Toxicologic enhancement occurredonly with delayed administration of acetaminophen; however,the maximal enhancement observed with a 6-hr delay was stillevident with a 12-hr delay. Conversely, inhibition of acetaminophenhepatotoxicity was observed if acetaminophen was given either2 hr or 18 hr after halothane. These observations may have clinicalrelevance, and they indicate potential complications in theinterpretation of results obtained from animals subjected togeneral anesthesia. 相似文献
6.
Chuyuan Wang Patricia Solís Lily Villa Nayan Khare Elizabeth A. Wentz Aaron Gettel 《Journal of urban health》2021,98(3):344
The objective of the present study was to examine the effects of a confluence of demographic, socioeconomic, housing, and environmental factors that systematically contribute to heat-related morbidity in Maricopa County, Arizona, from theoretical, empirical, and spatial perspectives. The present study utilized ordinary least squares (OLS) regression and multiscale geographically weighted regression (MGWR) to analyze health data, U.S. census data, and remotely sensed data. The results suggested that the MGWR model showed a significant improvement in goodness of fit over the OLS regression model, which implies that spatial heterogeneity is an essential factor that influences the relationship between these factors. Populations of people aged 65+, Hispanic people, disabled people, people who do not own vehicles, and housing occupancy rate have much stronger local effects than other variables. These findings can be used to inform and educate local residents, communities, stakeholders, city managers, and urban planners in their ongoing and extensive efforts to mitigate the negative impacts of extreme heat on human health in Maricopa County. 相似文献
7.
【目的】 分析母语非英语国家科技期刊出版策略,为国内期刊国际化发展提供借鉴。【方法】 以巴西SciELO平台为例,通过文献调研、平台调研、双语期刊案例调研等方法剖析巴西期刊出版策略。【结果】 作为国际上首个开放出版平台,SciELO平台更多是面向本国期刊质量提升与评估优化、数字化出版、出版语种平衡及国际影响力提升需要而提出的发展策略。【结论】 SciELO平台本身就是一种国际化策略,发挥了“造船出海“的功能,对整体提升巴西期刊国际影响力具有非常重要的作用,其数字出版平台的牵引作用和语种的平衡发展方式值得我国借鉴。 相似文献
8.
An initiative by the North West Thames Regional Information Technology Agency has resulted in the provision of some 30 CD-ROM drives and copies of the MEDLINE database in National Health Service libraries. The development of the scheme and its implementation are described and future developments outlined. 相似文献
9.
库宝善 《北京大学学报(医学版)》1999,31(3):D2
睡眠有3种成分:浅睡眠、慢波睡眠(slowwavesleep,SWS)和快眼动睡眠。提出催眠药物开发新构想,即SWS是最重要的睡眠成分,选择性增加深睡眠的催眠药物最重要,它将对改善失眠,辅助治疗焦虑症、抑郁症和痴呆症具有重要意义。近十年研究进展包括:(1)腹外侧视前区结节乳头体可能是睡眠觉醒的中枢发生部位。基底前脑吻端pGD2敏感性睡眠促进区参与睡眠调节;(2)生长激素释放激素、褪黑激素、pGD2、IL1和腺苷均可增加SWS。本系神经药理研究室关于SWS的研究工作包括:(1)建立起家兔和大鼠睡眠成分自动分析系统(autoanalysissleepingstagessystems,ASS);(2)利用ASS研究了免疫增强剂如转移因子、胞壁酰二肽、肿瘤坏死因子,以及5HT1A受体激动剂和5HT2受体拮抗剂对睡眠成分的影响;(3)探讨5HT1A受体、REM睡眠和5HT2受体间的关系。近十年睡眠调节的研究进展证明“构想”的可行性和正确性,并提示,在中枢可能存在免疫增强TNF增多5HT更新率增加SWS途径。激动5HT1A自身受体与拮抗5HT2受体有类似效果,二者间有协同作用。开发选择性延长 相似文献
10.
Karen L. Durinzi Anne Colston Wentz Erwin M. Saniga Deborah E. Johnson Susan E. Lanzendorf 《Journal of assisted reproduction and genetics》1997,14(4):199-204
Purpose:
Our purpose was (1) to determine if in vitro maturation of unstimulated oocytes could be improved with the addition of urofollitropin;
(2) to evaluate the output of estradiol, testosterone, progesterone, and androstenedione by the cultured oocyte-cumulus complex;
and (3) to ascertain if steroid hormone production of the oocyte-cumulus complex correlates with final oocyte maturation stage.
Methods:
Fifty-eight immature oocytes were obtained from 11 regularly cycling women undergoing oophorectomy. The oocyte-cumulus complexes
were randomly assigned to control medium (Ham’s F-10 supplemented with 7.5% fetal bovine serum) or test medium (control medium
supplemented with 75 mIU/ml of urofollitropin).
Results:
(1) The addition of urofollitropin to oocyte culture medium does not significantly increase the ability of the oocyte to achieve
the metaphase II stage; (2) the addition of urofollitropin significantly increases the production of progesterone, testosterone,
and androstenedione by the oocyte-cumulus complex; and (3) there is no difference in the production of estradiol, progesterone,
testosterone, and androstenedione by the oocyte-cumulus complex at the germinal vesicle, metaphase I or metaphase II stage
of oocyte maturation.
Conclusions:
This information is of importance in the use of oophorectomy specimens for patients who must undergo an oophorectomy but desire
to attempt pregnancy using their oocytes, in the use of oophorectomy specimens for donor oocytes, or for patients undergoing
in vitro fertilization using immature oocyte collection. 相似文献