全文获取类型
收费全文 | 1990篇 |
免费 | 213篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 61篇 |
妇产科学 | 60篇 |
基础医学 | 318篇 |
口腔科学 | 9篇 |
临床医学 | 274篇 |
内科学 | 311篇 |
皮肤病学 | 52篇 |
神经病学 | 115篇 |
特种医学 | 33篇 |
外科学 | 252篇 |
综合类 | 42篇 |
一般理论 | 1篇 |
预防医学 | 239篇 |
眼科学 | 105篇 |
药学 | 155篇 |
中国医学 | 1篇 |
肿瘤学 | 161篇 |
出版年
2021年 | 23篇 |
2020年 | 20篇 |
2019年 | 30篇 |
2018年 | 41篇 |
2017年 | 20篇 |
2016年 | 45篇 |
2015年 | 38篇 |
2014年 | 46篇 |
2013年 | 62篇 |
2012年 | 91篇 |
2011年 | 96篇 |
2010年 | 43篇 |
2009年 | 64篇 |
2008年 | 76篇 |
2007年 | 102篇 |
2006年 | 100篇 |
2005年 | 77篇 |
2004年 | 77篇 |
2003年 | 67篇 |
2002年 | 71篇 |
2001年 | 59篇 |
2000年 | 68篇 |
1999年 | 49篇 |
1998年 | 33篇 |
1997年 | 31篇 |
1996年 | 18篇 |
1995年 | 19篇 |
1994年 | 25篇 |
1993年 | 24篇 |
1992年 | 37篇 |
1991年 | 27篇 |
1990年 | 30篇 |
1989年 | 30篇 |
1988年 | 27篇 |
1987年 | 23篇 |
1986年 | 36篇 |
1985年 | 51篇 |
1984年 | 28篇 |
1983年 | 19篇 |
1982年 | 16篇 |
1979年 | 19篇 |
1978年 | 17篇 |
1977年 | 26篇 |
1976年 | 20篇 |
1974年 | 22篇 |
1973年 | 17篇 |
1972年 | 16篇 |
1971年 | 30篇 |
1970年 | 32篇 |
1969年 | 19篇 |
排序方式: 共有2205条查询结果,搜索用时 78 毫秒
11.
We report here the development of anti-Fy5 in a young Negro female with sickle cell disease. The antibody was responsible for a delayed hemolytic transfusion reaction. We believe this is the first report of such an antibody in Europe. 相似文献
12.
D Macfoy J Hewitt E Barker W A Francis 《European journal of obstetrics, gynecology, and reproductive biology》1992,43(1):35-37
Over a 13-month period in a newly opened assisted conception unit at the Women's Hospital, Liverpool, gamete intra-fallopian transfer using donor semen, GIFT (D) was offered to eighteen couples who had failed to conceive after numerous cycles of treatment with artificial insemination by donor semen (AID). The indication for the use of donor semen was either azo- or severe oligoaesthenospermia, and, in addition, the female partners have been exhaustively investigated with no major cause found to account for the couple's infertility. Using a basic clomiphene citrate and human menopausal gonadotrophin protocol it was possible to achieve a pregnancy rate of 56% per GIFT (D) cycle. As a consequence of these results it is now our policy to treat couples whose infertility is due to an unresolvable male factor with AID for 12 cycles only. If they have been unsuccessful in achieving a pregnancy after this time, they are offered GIFT (D). 相似文献
13.
14.
15.
16.
Preparation for bone marrow transplantation (BMT) uses the extremely emetogenic combination of chemotherapy and total body irradiation (TBI). Ondansetron is a selective 5-HT3 antagonist and has clear anti-emetic capabilities. The efficacy of the drug was assessed in 15 children (aged 2-17 years) who received high dose cyclophosphamide (on days -6 and -5) and TBI (days -3 to 0 inclusive). During days -6 to -4 when the emetic effect of cyclophosphamide would be most pronounced, 12 of the 15 patients (80%) had fewer than five emetic episodes during their worst 24-h period, 11 (73%) had fewer than three vomits whilst nine (60%) experienced no vomiting or retching. Eleven patients progressed to TBI and 10 (91%) had fewer than five emetic events in the worst 24-h period (days -3 to +2), six (55%) had no vomiting at all. Of 100 evaluable 'patient-days' 83 (83%) were without any vomiting or retching and a further 10 'patient-days' had only one or two emetic episodes. There were no significant side-effects noted and in particular no extrapyramidal reactions. Headaches and constipation, which have been seen in adult studies, were not reported by patient or parent on any of the study days and transient elevation of liver enzymes were noted in only two patients. Ondansetron has a major role in preparing patients for BMT. 相似文献
17.
Composite tissue (limb) allografts in rats. III. Development of donor-host lymphoid chimeras in long-term survivors 总被引:2,自引:0,他引:2
C W Hewitt K S Black S F Dowdy G A Gonzalez B M Achauer D C Martin D W Furnas E B Howard 《Transplantation》1986,41(1):39-43
Eight LEW rat recipients possessing long-term-surviving (206-701 days) LBN vascularized hind limb allografts (CTAs) were tested for donor-host lymphoid chimerism. The recipients received various cyclosporine (CsA) treatment protocols in order to induce indefinite CTA acceptance. Histological examination of long-term-surviving CTAs demonstrated normal-appearing bone marrow in the donor limb. Lymphocytes isolated from host hemopoietic tissues (peripheral blood and/or spleen) by ficoll-hypaque density gradient centrifugation were tested against LEW-anti-BN antisera. Comparisons were made to standard curves employing various known concentrations of LBN and LEW cell combinations. The level of lymphocyte agglutination (dependent variable) showed a significant (P less than 0.025-0.005) linear relationship to the concentration of LBN donor cells (independent variable) present. Lymphocyte suspensions isolated from long-term CTA host peripheral blood and/or spleen showed a mean of 19.7% (+/- 9.7-95% confidence interval) donor LBN mononuclear cells present. Thus, it appeared that lymphoid cells originated from, and/or were released from LBN donor bone marrow into the circulation, resulting in chimeric repopulation of hemopoietic tissues. The presence of donor immunocytes in these limb allograft recipients may have been beneficial, and thus could have helped contribute to the long-term CTA survival observed. 相似文献
18.
OBJECTIVES: The purpose of this study was to ascertain whether individuals with anorexia nervosa are more likely to commit suicide, as suggested by previously noted associations between anorexia nervosa and mood disorders. METHODS: Data from death records representing over 5 million women were examined, yielding 571 cases in which anorexia nervosa was mentioned as an existing condition. The women with anorexia were compared with 1713 control subjects matched for age, sex, and race. RESULTS: The percentage of suicides among those listed as having anorexia nervosa was only 1.4%, compared with 4.1% for the controls. CONCLUSIONS: These findings suggest that the suicide rate is not elevated among individuals currently suffering from anorexia nervosa. 相似文献
19.
Proteoglycans are involved in a variety of cell-cell and cell-matrix interactions. These include cell adhesion, growth regulation and a number of developmental processes. Their involvement in such interactions may be of particular importance in retinitis pigmentosa (RP) because of the detachment and migration of retinal pigment epithelial (RPE) cells often associated with this condition. Because of these important functions in cell behavior, we have been studying the proteoglycans produced by human RPE and how these may be altered in RP. Confluent cultures of RPE from normal donors and from two donors with dominantly inherited RP were labeled with 3H-glucosamine and 35SO4 and the proteoglycans isolated from the medium, substratum and two cell membrane-associated compartments, designated "EDTA-released" and "cell-associated." The proteoglycans were analyzed for size distribution by Sepharose CL-4B chromatography and for glycosaminoglycan (GAG) composition based on enzymatic and chemical susceptibilities. Differences in size distribution and GAG composition were found between the two cell-associated compartments on normal cells. Retinitis pigmentosa proteoglycans differed from their normal counterparts in corresponding compartments both in size distribution and GAG composition. Most affected were those proteoglycans released from the cell surface by EDTA. These findings may be of importance in retinitis pigmentosa since alterations in these molecules could influence the way RPE cells interact with their microenvironment. 相似文献
20.
Given that knowledge regarding the etiology of comorbidity between disorders can have a significant impact on research regarding the classification, treatment, and etiology of the disorders, the ability to reject incorrect hypotheses regarding the causes of comorbidity is very important. A simulation study was conducted to assess the validity of the Neale and Kendler (1995) model-fitting approach in examining the etiology of comorbidity between two disorders. First, data were simulated under the assumptions of the 13 alternative comorbidity models described by Neale and Kendler. Second, model-fitting analyses testing the comorbidity models were conducted on the simulated datasets. Thirteen sets of data with varying model parameters were simulated to test Neale and Kendler's assertion that their model-fitting approach is appropriate across a range of potential prevalences and degrees of familiality. The validity of the model-fitting approach in examining unselected twin data and a combination of selected family data and unselected family data was explored. The model-fitting approach successfully discriminated several classes of comorbidity models, although discrimination between models within classes of related models was less accurate. Results suggest that the model-fitting approach can be a useful tool in examining the etiology of the comorbidity between disorders if the caveats of the present study's results are considered carefully. As predicted by Neale and Kendler, variations in the disorder prevalences and familial correlations did not affect the validity of their model-fitting approach, but affected the power to discriminate the correct model. As suggested by Neale and Kendler, the model-fitting approach can be applied to both unselected and selected data and to both twin and family data. 相似文献