全文获取类型
收费全文 | 1062篇 |
免费 | 115篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 11篇 |
妇产科学 | 15篇 |
基础医学 | 92篇 |
口腔科学 | 25篇 |
临床医学 | 139篇 |
内科学 | 273篇 |
皮肤病学 | 3篇 |
神经病学 | 81篇 |
特种医学 | 37篇 |
外科学 | 174篇 |
综合类 | 37篇 |
一般理论 | 1篇 |
预防医学 | 107篇 |
眼科学 | 46篇 |
药学 | 70篇 |
中国医学 | 1篇 |
肿瘤学 | 52篇 |
出版年
2022年 | 10篇 |
2021年 | 18篇 |
2019年 | 12篇 |
2018年 | 19篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 8篇 |
2014年 | 27篇 |
2013年 | 36篇 |
2012年 | 34篇 |
2011年 | 40篇 |
2010年 | 30篇 |
2009年 | 21篇 |
2008年 | 47篇 |
2007年 | 44篇 |
2006年 | 43篇 |
2005年 | 53篇 |
2004年 | 51篇 |
2003年 | 48篇 |
2002年 | 42篇 |
2001年 | 29篇 |
2000年 | 30篇 |
1999年 | 22篇 |
1998年 | 12篇 |
1997年 | 12篇 |
1994年 | 7篇 |
1992年 | 25篇 |
1991年 | 19篇 |
1990年 | 26篇 |
1989年 | 27篇 |
1988年 | 22篇 |
1987年 | 21篇 |
1986年 | 20篇 |
1985年 | 12篇 |
1984年 | 14篇 |
1983年 | 10篇 |
1982年 | 15篇 |
1981年 | 10篇 |
1979年 | 14篇 |
1978年 | 14篇 |
1977年 | 11篇 |
1976年 | 21篇 |
1975年 | 11篇 |
1974年 | 19篇 |
1973年 | 17篇 |
1972年 | 13篇 |
1971年 | 12篇 |
1970年 | 14篇 |
1969年 | 8篇 |
1968年 | 14篇 |
排序方式: 共有1192条查询结果,搜索用时 15 毫秒
1.
M Parry-Billings B Leighton G D Dimitriadis J Bond E A Newsholme 《Biochemical pharmacology》1990,40(5):1145-1148
The effects of physiological and pathological concentrations of glucocorticoids were investigated using the glucocorticoid antagonist RU486 and the synthetic glucocorticoid dexamethasone, respectively. The effects of these treatments on the concentrations of glutamine and other amino acids in skeletal muscle and plasma and on the rates of release of glutamine and alanine from incubated preparations of skeletal muscle of the rat were investigated. Dexamethasone treatment increased the concentration of glutamine and the rate of release of this amino acid from incubated soleus muscle preparations. This treatment decreased the concentration of glutamine in both gastrocnemius and EDL muscles, but was without effect on the rate of glutamine release from EDL muscles. In contrast, administration of the glucocorticoid antagonist RU486 decreased the rate of glutamine release from muscle. It is concluded that glucocorticoids have marked effects on the metabolism of glutamine by skeletal muscle per se and that these hormones may be important in the control of the rate of glutamine release from muscle in both physiological and pathological conditions. 相似文献
2.
3.
Sharon Leighton 《Journal of child and adolescent psychiatric nursing》2008,21(1):24-34
TOPIC: Bereavement therapy as a catalyst for spiritual growth. PURPOSE: This study aims to review the literature and reflect on the bereavement therapy undertaken with two adolescents who had been bereaved during childhood. SOURCES: Research articles and books identified through a combination of electronic and manual searches. CONCLUSIONS: It would appear that grief therapy could facilitate spiritual growth in such circumstances. Further in-depth studies are required to identify how typical or atypical this experience is, and to contribute to the evidence base for working with bereaved children and adolescents. 相似文献
4.
5.
Joseph Leighton 《Methods in Cell Science》1992,14(4):201-207
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity. 相似文献
6.
Christopher D Wells Russell I Heigh Virender K Sharma Michael D Crowell Suryakanth R Gurudu Jonathan A Leighton Nora Mattek David E Fleischer 《BMC gastroenterology》2007,7(1):19
Background
Many factors impacting cecal intubation rates have been examined in detail; however, little information exists regarding the effect of the timing of the procedure. We sought to examine any difference in cecal intubation rates between morning and afternoon colonoscopies and identify factors contributing to a discrepancy. 相似文献7.
G E Leighton T Griesbacher R G Hill J Hughes 《European journal of pharmacology》1989,161(2-3):255-258
The reduction in food intake induced by i.p. injections of the cholecystokinin (CCK) analogue caerulein was antagonised by a low dose (0.25 mumol/kg s.c.) of the selective CCK antagonist L-364,718. To block the anorectic effect of centrally administered caerulein a dose of 25 mumol/kg of L-364,718 was required, demonstrating that central CCK receptors can be blocked effectively in the rat by choosing appropriate doses of L-364,718. 相似文献
8.
B L Leighton T G Cheek J B Gross J L Apfelbaum B B Shantz B B Gutsche H Rosenberg 《Anesthesiology》1986,64(2):202-205
Serum cholinesterase activity decreases 30% during pregnancy and remains depressed during the postpartum period. However, succinylcholine recovery is not prolonged in term-pregnant patients. This contrasts with results obtained in other patients with decreased serum cholinesterase activity. To better understand this paradox, the authors compared serum cholinesterase activity and recovery from succinylcholine, 1 mg/kg, in nonpregnant (with and without oral contraceptive use), in term-pregnant, and in postpartum patients. Serum cholinesterase activity was lower in both term-pregnant (3.66 +/- 0.39 U/ml, means +/- SE) and postpartum (2.84 +/- 0.35 U/ml) patients than in nonpregnant patients not taking oral contraceptives (5.01 +/- 0.33 U/ml, P less than 0.05). Cholinesterase activity in postpartum patients also was significantly lower than in nonpregnant patients taking oral contraceptives (4.81 +/- 0.63, P less than 0.05). In contrast, the time to 25% twitch-height recovery did not differ between term-pregnant (470 +/- 56 s) and nonpregnant patients taking (499 +/- 29 s) or not taking (501 +/- 21 s) oral contraceptives, but was significantly increased in postpartum patients (685 +/- 22 s, P less than 0.001). The similar duration of action of succinylcholine in term-pregnant patients (with decreased serum cholinesterase activities) and nonpregnant patients may be related to the increased volume of distribution of succinylcholine at term. 相似文献
9.
Epidemiological aspects of back pain: the incidence and prevalence of back pain in nurses compared to the general population 总被引:8,自引:1,他引:7
Two studies using retrospective questionnaires were conductedto obtain epidemiological information from nursing personnel(n= 1134) and among an age-and gender-matched cross-secton ofthe general population (n= 315). The point and annual prevalenceof back pain did not differ between the two sample groups. Nursesdemonstrated a greater annual incidence of back pain (14.7%,compared to 11.5% in non-nurses). The point prevalence of backpain increased with age in both sample groups. Nurses consideredpatient-handling tasks instrumental in the onset of back painsymptoms. Comparison of results with those obtained from a similarstudy published in 1983 indicated an increase of almost 40%in the prevalence of back pain symptoms in nurses, althoughthe linearity of the rise was not ascertained. The implementationof guidelines on the manual handling of loads has led to revisedtraining procedures and these may have influenced the epidemiologicalfindings. 相似文献
10.
Budowle B Johnson MD Fraser CM Leighton TJ Murch RS Chakraborty R 《Critical reviews in microbiology》2005,31(4):233-254
Because of the availability of pathogenic microorganisms and the relatively low cost of preparing and disseminating bioweapons, there is a continuing threat of biocrime and bioterrorism. Thus, enhanced capabilities are needed that enable the full and robust forensic exploitation and interpretation of microbial evidence from acts of bioterrorism or biocrimes. To respond to the need, greater resources and efforts are being applied to the burgeoning field of microbial forensics. Microbial forensics focuses on the characterization, analysis and interpretation of evidence for attributional purposes from a bioterrorism act, biocrime, hoax or inadvertent agent release. To enhance attribution capabilities, a major component of microbial forensics is the analysis of nucleic acids to associate or eliminate putative samples. The degree that attribution can be addressed depends on the context of the case, the available knowledge of the genetics, phylogeny, and ecology of the target microorganism, and technologies applied. The types of genetic markers and features that can impact statistical inferences of microbial forensic evidence include: single nucleotide polymorphisms, repetitive sequences, insertions and deletions, mobile elements, pathogenicity islands, virulence and resistance genes, house keeping genes, structural genes, whole genome sequences, asexual and sexual reproduction, horizontal gene transfer, conjugation, transduction, lysogeny, gene conversion, recombination, gene duplication, rearrangements, and mutational hotspots. Nucleic acid based typing technologies include: PCR, real-time PCR, MLST, MLVA, whole genome sequencing, and microarrays. 相似文献