全文获取类型
收费全文 | 1760篇 |
免费 | 159篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 94篇 |
妇产科学 | 106篇 |
基础医学 | 196篇 |
口腔科学 | 42篇 |
临床医学 | 210篇 |
内科学 | 411篇 |
皮肤病学 | 46篇 |
神经病学 | 26篇 |
特种医学 | 146篇 |
外科学 | 201篇 |
综合类 | 136篇 |
预防医学 | 93篇 |
眼科学 | 10篇 |
药学 | 92篇 |
1篇 | |
中国医学 | 74篇 |
肿瘤学 | 39篇 |
出版年
2021年 | 15篇 |
2018年 | 12篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 37篇 |
2014年 | 50篇 |
2013年 | 45篇 |
2012年 | 63篇 |
2011年 | 56篇 |
2010年 | 61篇 |
2009年 | 47篇 |
2008年 | 56篇 |
2007年 | 49篇 |
2006年 | 49篇 |
2005年 | 28篇 |
2004年 | 25篇 |
2003年 | 15篇 |
2002年 | 22篇 |
2001年 | 24篇 |
2000年 | 20篇 |
1999年 | 26篇 |
1998年 | 45篇 |
1997年 | 59篇 |
1996年 | 53篇 |
1995年 | 45篇 |
1994年 | 58篇 |
1993年 | 37篇 |
1992年 | 22篇 |
1991年 | 22篇 |
1990年 | 26篇 |
1989年 | 36篇 |
1988年 | 38篇 |
1987年 | 32篇 |
1986年 | 33篇 |
1985年 | 21篇 |
1984年 | 24篇 |
1983年 | 24篇 |
1982年 | 18篇 |
1981年 | 26篇 |
1980年 | 21篇 |
1976年 | 13篇 |
1959年 | 35篇 |
1958年 | 58篇 |
1957年 | 87篇 |
1956年 | 45篇 |
1955年 | 75篇 |
1954年 | 67篇 |
1953年 | 17篇 |
1952年 | 14篇 |
1949年 | 10篇 |
排序方式: 共有1932条查询结果,搜索用时 0 毫秒
11.
Improvement in gait parameters after lengthening for the treatment of limb-length discrepancy 总被引:3,自引:0,他引:3
Bhave A Paley D Herzenberg JE 《The Journal of bone and joint surgery. American volume》1999,81(4):529-534
BACKGROUND: Patients who have limb-length discrepancy demonstrate an altered gait pattern or a limp. The purpose of this prospective study was to compare the objective gait parameters for the shorter lower limb with those for the longer lower limb before and after lengthening and to compare these data with those for a group of twenty subjects who had no limb-length discrepancy. METHODS: Eighteen patients had equalization of limb length to within one centimeter. We analyzed the stance time, the second peak of the vertical ground-reaction-force vector, and the rate of loading with use of two force-plates arranged in a series. RESULTS: The difference in the mean stance times between the shorter and longer limbs before lengthening was 12 percent, whereas that after lengthening was 2.4 percent; the difference between the values before and after lengthening was significant (p<0.001). The difference in the stance times between the limbs of the patients who did not have limb-length discrepancy was 2 percent. Preoperatively, the mean second peak was 104 percent of body weight for the shorter limb compared with 116 percent for the longer limb; this difference was significant (p<0.001). After lengthening, the mean second peak for the shorter limb increased to 113 percent of body weight. The difference in the means for the second peak before and after lengthening was significant (p<0.001). With the numbers available, no significant difference was detected in the means for the second peak between the shorter and longer limbs after lengthening (p = 0.12). CONCLUSIONS: This study shows that lengthening of the shorter limb of patients who have limb-length discrepancy can normalize symmetry of quantifiable stance parameters and eliminate a limp. 相似文献
12.
Economic costs of functional dyspepsia 总被引:5,自引:0,他引:5
Dyspepsia is defined as chronic or recurrent symptoms believed to originate in the upper gastrointestinal tract. When routine investigation results in no identifiable explanation for those symptoms patients are labelled as having functional dyspepsia. In community-based surveys, approximately 30% of the otherwise apparently healthy population report dyspeptic symptoms and the majority are believed to have functional dyspepsia. Although only 1 in 4 or 5 patients make use of healthcare resources, this patient category is one of the largest in ambulatory care (1.6 to 5% of all consultations in general practice). The annual frequency of consultations for functional dyspepsia in Sweden has been estimated at 47 per 1000 population. In consequence of its high prevalence and associated absenteeism, the total costs of functional dyspepsia are considerable. In Sweden in 1981, the costs were estimated at $US55 000 per 1000 population ($US113 630 in 1991 dollars). The most cost-effective management strategy remains to be defined. Evidence is accumulating that the traditional 'wait-and-see' policy with initial empirical therapeutic trials without investigation may not be the most cost conserving strategy. 相似文献
13.
The purpose of this study was to determine changes in cast weight during the first 48 hours after application so that the true weight of a neonate can be estimated without the need for removing the cast. Five types of cast materials were compared. Cast weight measurements were obtained before and after application and at intervals during 48 hours. Final cast weight averaged 107.5% of dry weight for plaster and 99% of dry weight for synthetic cast materials. For very low birth weight infants, the difference between the initial wet weight of plaster of Paris and its final dry weight may be significant for calculating drug and fluid dosages. The weight of an infant can now be calculated without the necessity of cast removal. 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.
20.