全文获取类型
收费全文 | 1550篇 |
免费 | 130篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 21篇 |
妇产科学 | 37篇 |
基础医学 | 244篇 |
口腔科学 | 34篇 |
临床医学 | 126篇 |
内科学 | 461篇 |
皮肤病学 | 23篇 |
神经病学 | 169篇 |
特种医学 | 46篇 |
外国民族医学 | 3篇 |
外科学 | 158篇 |
综合类 | 11篇 |
预防医学 | 104篇 |
眼科学 | 43篇 |
药学 | 79篇 |
中国医学 | 1篇 |
肿瘤学 | 90篇 |
出版年
2023年 | 9篇 |
2022年 | 12篇 |
2021年 | 26篇 |
2020年 | 22篇 |
2019年 | 29篇 |
2018年 | 36篇 |
2017年 | 13篇 |
2016年 | 21篇 |
2015年 | 37篇 |
2014年 | 31篇 |
2013年 | 55篇 |
2012年 | 92篇 |
2011年 | 88篇 |
2010年 | 52篇 |
2009年 | 48篇 |
2008年 | 84篇 |
2007年 | 85篇 |
2006年 | 103篇 |
2005年 | 77篇 |
2004年 | 68篇 |
2003年 | 74篇 |
2002年 | 59篇 |
2001年 | 45篇 |
2000年 | 42篇 |
1999年 | 44篇 |
1998年 | 19篇 |
1997年 | 16篇 |
1996年 | 18篇 |
1995年 | 11篇 |
1994年 | 12篇 |
1993年 | 16篇 |
1992年 | 27篇 |
1991年 | 25篇 |
1990年 | 29篇 |
1989年 | 25篇 |
1988年 | 27篇 |
1987年 | 19篇 |
1986年 | 23篇 |
1985年 | 27篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1975年 | 6篇 |
1970年 | 7篇 |
1968年 | 7篇 |
1967年 | 7篇 |
1966年 | 6篇 |
排序方式: 共有1684条查询结果,搜索用时 15 毫秒
1.
2.
3.
B Delbosc X Piquot P Herve M Montard 《Bulletin des sociétés d'ophtalmologie de France》1990,90(4):421-427
Using organ-culture preservation human corneas were preserved up to 5 weeks in a modified tissue culture medium at 37 degrees C. The endothelial viability was examined after staining with trypan-blue 0.3%, after determination of endothelial cell density and cell loss and by light microscopy after staining with trypan-blue 0.3% and alizarin red 1%. The biochemical analysis of the medium (pH, glucose, lactate) has allowed the evaluation of three kinds of storage. The influence of time preservation on the endothelial viability and the metabolic conditions are determined. At the end of this study a clinical trial is proposed. 相似文献
4.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA. 相似文献
5.
C Rouzioux J Puel H Agut F Brun-Vézinet F Ferchal C Tamalet P Descamps H Fleury 《AIDS (London, England)》1992,6(4):373-377
OBJECTIVE: To compare two published methods for determining plasma viraemia in HIV-seropositive patients, with reference to a cellular viraemia assay. PATIENTS, PARTICIPANTS: Three patient groups were defined according to CD4 cell count: group I, less than 200 x 10(6)/l (23 patients); group II, 200-500 x 10(6)/l (18 patients); and group III, greater than 500 x 10(6)/l (13 patients). METHODS: The two reported methodologies were applied to all fresh samples, simultaneously and on the same day. RESULTS: The two techniques did not differ significantly in the detection of plasma viraemia: 82.3% of group I patients and 55% of group II patients were positive, while all group III patients were negative. Cellular viraemia was positive for 96% of the overall population. CONCLUSIONS: These results, obtained in a network of seven French laboratories involved in clinical trials, confirm that both plasma viraemia and cellular viraemia are useful virological markers. 相似文献
6.
OBJECTIVES: This article examines the differences found between clientele with severe mental health problems and their key health workers in terms of assessing service users' needs in 6 Quebec service areas. METHOD: We questioned 165 pairs of users and staff, using the Camberwell Assessment of Needs questionnaire. The profile of serious and overall problems encountered by clientele from each of the sites was compared. RESULTS: The sites with the greatest degree of user-staff agreement in identifying problems were also the ones where users considered that local services best met their needs. CONCLUSIONS: The study demonstrated that, in needs assessment, major differences exist between the perceptions of users and their key workers in the various sites. These differences can be explained in part by users' individual characteristics, by types of needs, by local particularities, and by service use. 相似文献
7.
Francois P Huyghe A Charbonnier Y Bento M Herzig S Topolski I Fleury B Lew D Vaudaux P Harbarth S van Leeuwen W van Belkum A Blanc DS Pittet D Schrenzel J 《Journal of clinical microbiology》2005,43(7):3346-3355
Fast and reliable genotyping methods that allow real-time epidemiological surveillance would be instrumental to monitoring of the spread of methicillin-resistant Staphylococcus aureus. We describe an automated variable-number tandem repeat-based method for the rapid genotyping of Staphylococcus aureus. Multiplex PCR amplifications with eight primer pairs that target gene regions with variable numbers of tandem repeats were resolved by microcapillary electrophoresis and automatically assessed by cluster analysis. This genotyping technique was evaluated for its discriminatory power and reproducibility with clinical isolates of various origins, including a panel of control strains previously characterized by several typing methods and collections from either long-term carriers or defined nosocomial outbreaks. All steps of this new procedure were developed to ensure a rapid turnaround time and moderate cost. The results obtained suggest that this rapid approach is a valuable tool for the genotyping of S. aureus isolates in real time. 相似文献
8.
Dondji B Duchon S Diabate A Herve JP Corbel V Hougard JM Santus R Schrevel J 《Journal of medical entomology》2005,42(4):652-656
The effectiveness of light-induced killing of mosquito larvae in the presence of photosensitizers was studied with larvae of Aedes aegypti (L.), Anopheles stephensi (Liston), and Culex quinquefasciatus Say grown in the laboratory and of Cx. quinquefasciatus grown under field conditions. Tested photosensitizers included xanthene, chlorin, and porphyrin derivatives. All the larvae were treated at the fourth instar. Preliminary laboratory experiments showed a light-induced lethal effect of Rose Bengal (RB) on three species of mosquito larvae. Compared with other photosensitizers, RB seemed to be more efficient at even lower concentration than chlorin (e6) and chlorophyllin on Ae. aegypti larvae. Among the four porphyrin derivatives, i.e., chloroquinoline tetraphenyl propioamidoporphine, tetraphenyl porphine tetrasulfonate, hematoporphyrin (HP), and tetraphenylporphinepropionic acid porphine, HP was the only effective photosensitizer on Ae. aegypti larvae. The best conditions for field tests using RB were conducted on Cx. quinquefasciatus in Bobo-Dioulasso, Burkina Faso. The mortality induced by RB varied from 80 to 96% obtained with unfiltered cesspit water to 0.4 to 6.7% in cesspits with a heavy load of organic materials, thus providing the basis for further developments of this technique under field conditions. 相似文献
9.
le Cotonnec Jean-Yves; Porchet Herve C.; Beltrami Vanya; Howles Colin 《Human reproduction (Oxford, England)》1993,8(10):1604-1611
These studies were designed to compare the pharmacokinetic characteristicsof a very highly purified urinary human follicle stimulatinghormone (FSH-HP) preparation (sp. act. 9000 IU FSH/mg of protein),Metrodin HP®, with a standard urinary FSH preparation Metrodin®(FSH). The two preparations were administered in a balanced,random-order, cross-over sequence as single doses of 150IU,separated by 1 week of washout to 12 female volunteers by i.v.injection and to 12 male volunteers by i.m. and s.c. routes.FSH concentrations were measured by immunoradiometric assayand by an in-vitro rat granulosa cell aromatase bioassay. Afteran i.v. bolus, the pharmacokinetics of the two FSH preparationswere identical. Total clearance was 0.5 and 0.15 1/h respectivelyfor immunoassay and bioassay data. Immunoassay showed that thetwo preparations were similar for renal clearance (0.1 1/h),volumes of distribution at steady state (9 1), distributionand terminal half-lives (2 and 17 h, respectively). After parenteraladministrations, the absorption half-life of FSH was 3 h andthe apparent terminal half-life was 1.5 days. Both preparationshad relative bio-availabilities close to 100% for i.m. and s.c.administrations. Immunopurification, which results in a veryhighly purified FSH-HP, does not modify the pharmacokineticproperties of FSH. This study also confirmed that s.c. and i.m.doses of FSH-HP are equivalent from the pharmacokinetic andpharmacodynamic points of view. 相似文献
10.
Expression of matrix metalloproteinases and their inhibitors during the resorption of schistosome egg-induced fibrosis in praziquantel-treated mice 总被引:9,自引:0,他引:9
下载免费PDF全文
![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Schistosomiasis mansoni is a tropical helminthic disease characterized by parasite egg-induced granulomatous inflammation and cumulative fibrosis. Because fibrosis is influenced by the imbalance between degradative matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), we analysed the resorption of fibrous tissue and MMP/TIMP expression in the livers of S. mansoni-infected and praziquantel-cured mice. Worm elimination significantly enhanced survival rate, ameliorated the granulomatous pathology and reduced collagen I, III and IV gene expression at 6 and 12 months post-treatment. Compared to 6 months infected, untreated controls, liver fibrous tissue was resorbed by 71.4% at 12 months after treatment. At 3 months post-treatment, expression of the MMP-2, -3, -8, -10, -13, -14 and -16 genes decreased compared with untreated controls. By 6 months, a highly significant increase in MMP-10 gene expression was manifest. At 12 months, messages for all MMP genes decreased in relation to untreated controls. TIMP-1, -2 and -3 gene expression drastically decreased between 3 and 6 months. At 1 year, only TIMP-1 expression was significantly diminished. Overall, profibrogenic tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta and inducible nitric oxide synthase (iNOS) gene expression decreased. Antigen-stimulated splenocytes secreted significantly higher levels of interleukin (IL)-4, IL-5, IL-10 and IL-13 cytokines between 3 and 12 months after treatment. Production of interferon (IFN)-gamma was higher than in untreated controls 3 and 6 months after treatment. In conclusion, praziquantel-treated mice showed a slow resorption of liver fibrous tissue. Resorption is attributed to the precipitous drop in TIMP-1 gene expression level, which shifted the balance in favour of MMP message expression and presumed enhanced collagenase activity. 相似文献