全文获取类型
收费全文 | 2460045篇 |
免费 | 203941篇 |
国内免费 | 4623篇 |
专业分类
耳鼻咽喉 | 35249篇 |
儿科学 | 75524篇 |
妇产科学 | 64475篇 |
基础医学 | 346708篇 |
口腔科学 | 69297篇 |
临床医学 | 224603篇 |
内科学 | 486417篇 |
皮肤病学 | 49032篇 |
神经病学 | 209348篇 |
特种医学 | 98564篇 |
外国民族医学 | 887篇 |
外科学 | 373056篇 |
综合类 | 57530篇 |
现状与发展 | 2篇 |
一般理论 | 1113篇 |
预防医学 | 198844篇 |
眼科学 | 58015篇 |
药学 | 183745篇 |
5篇 | |
中国医学 | 4552篇 |
肿瘤学 | 131643篇 |
出版年
2018年 | 26211篇 |
2017年 | 20254篇 |
2016年 | 22248篇 |
2015年 | 25223篇 |
2014年 | 36340篇 |
2013年 | 54854篇 |
2012年 | 74620篇 |
2011年 | 78628篇 |
2010年 | 45989篇 |
2009年 | 44219篇 |
2008年 | 74493篇 |
2007年 | 79151篇 |
2006年 | 79760篇 |
2005年 | 77818篇 |
2004年 | 74780篇 |
2003年 | 72010篇 |
2002年 | 71153篇 |
2001年 | 113280篇 |
2000年 | 117144篇 |
1999年 | 99216篇 |
1998年 | 28900篇 |
1997年 | 26387篇 |
1996年 | 26129篇 |
1995年 | 25287篇 |
1994年 | 23755篇 |
1993年 | 22133篇 |
1992年 | 79850篇 |
1991年 | 76816篇 |
1990年 | 73932篇 |
1989年 | 71191篇 |
1988年 | 66200篇 |
1987年 | 65129篇 |
1986年 | 61618篇 |
1985年 | 58744篇 |
1984年 | 44652篇 |
1983年 | 38055篇 |
1982年 | 23427篇 |
1981年 | 20795篇 |
1980年 | 19442篇 |
1979年 | 41562篇 |
1978年 | 29255篇 |
1977年 | 24615篇 |
1976年 | 23060篇 |
1975年 | 24179篇 |
1974年 | 29849篇 |
1973年 | 28233篇 |
1972年 | 26390篇 |
1971年 | 24273篇 |
1970年 | 22856篇 |
1969年 | 21198篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A 60-year-old man developed hemiballismus due to an intracranial hemorrhage involving the subthalamic nucleus 8 weeks after orthotopic liver transplantation. The hemorrhage was thought to be due to alterations in cerebral blood flow following a period of hypotensive shock due to sepsis, in the presence of anticoagulant therapy and thrombocytopenia. This represents a rare neurologic complication of liver transplantation. 相似文献
992.
993.
Paul P. W. van Buul Iris M. Zandman Mira Grigorova Jan J. W. A. Boei Adayapalam T. Natarajan 《Chromosome research》1995,3(7):427-432
The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems. 相似文献
994.
J.I. Smedberg E. Lothigius I. Bodin A. Frykholm K. Nilner 《Clinical oral implants research》1993,4(1):39-46
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures. 相似文献
995.
Summary Two cases of documented HIV-1 transmission by needle stick and one case of probable transmission by eczematous lesion in three nurses in Germany are reported in the period 1988 to 1991. In two of the cases the nurse knew of the AIDS status of the index patient. A review of the three cases reiterates the importance of repeated training on the prevention of accident and on measures to be taken after an accident, as well as the need to keep the workplace free of additional burden when AIDS or HIV-infected patients are treated.
HIV-Übertragung durch Nadelstichverletzung und über offenes Ekzem. Drei Fälle aus Deutschland
Zusammenfassung Zwei dokumentierte HIV-Übertragungen über Nadelstichverletzung und eine Übertragung über ein offenes Hautekzem der Hand bei zwei Krankenschwestern und einem Pfleger aus den Jahren 1988 bis 1991 werden geschildert. Diese Übersicht der drei Fälle weist auf die Bedeutung von wiederholten Übungen hin, um einen Unfall zu verhüten und auf Maßnahmen die nach einem Unfall zu ergreifen sind. Unter anderem auf die Notwendigkeit den Arbeitsplatz von zusätzlichen Gegenständen freizuhalten, wenn AIDS- oder HIV-infizierte Patienten behandelt werden.相似文献
996.
Herbert Radner Yosuf El-Shabrawi Robert H. Eibl Oliver Brüstle Lukas Kenner Paul Kleihues Otmar D. Wiestler 《Acta neuropathologica》1993,86(5):456-465
Introduction into fetal rat brain cells of a replication-defective retroviral vector harboring v-Ha-ras and v-gag-myc rapidly causes the induction of highly malignant undifferentiated neuroectodermal tumors following transplantation into the brains of syngeneic hosts [Wiestler, et al. (1992) Cancer Res. 52: 3760–3767]. In the present study, we have investigated the modulating effect of the developmental stage of neural target cells and of the dose of the retroviral vector used in the grafting experiments. Exposure of fetal cells from embryonic day (E)12 or E14 produced a 100% incidence of malignant neuroectodermal tumors which led to the death of recipient animals after a median latency period of 32 days. A 100-fold reduction of the virus dose from 2.062×106 to 2.062×104 focus-forming units/ml resulted in a lower tumor incidence of 25%. Of six neural grafts exposed to v-Ha-ras and v-myc at E16, only one showed evidence of tumorigenesis (low-grade astrocytoma and hemangioma). All other transplants were morphologically normal for observation periods of 26 weeks, indicating a marked loss of transforming activity of ras and myc in more advanced stages of brain development. In retrovirus-exposed donor cells which caused the development of neural tumors in recipient rats, malignant transformation was also evident during culture in vitro, usually after 9–12 days. Oncogene complementation was also studied in the newborn rat brain. After microinjection of the retroviral vector into the brain at postnatal day (P)0, P1 and P3, 5 out of 20 animals (25%) developed a total of seven brain tumors. Histopathologically, three of these neoplasms were malignant neuroectodermal tumors which, in contrast to those induced in fetal brain transplants showed evidence of focal glial and/or neuronal differentiation. In addition, we observed one oligodendroglioma, two hemangiomas and a malignant hemangioendothelioma. These data indicate that neural precursor cells and endothelia of the rat brain represent the major target cells for the complementary action of ras and myc and that the use of target cells from later developmental stages (E16 and postnatal) leads to the induction of both primitive and more differentiated neoplasms.These studies were supported by the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich (Erwin Schrödinger fellowship, JO501-MED), by the Swiss National Science Foundation and by the Cancer League of the Kanton of Zürich 相似文献
997.
Summary Seventy-nine patients with a history of the subacromial impingement syndrome were treated by arthroscopic acromioplasty. The results were evaluated with a new scoring system designed to assess subjective symptoms before and after operation. The outcome was related to the pathological lesions of the rotator cuff seen at arthroscopy and graded by our modification of the Neer classification. The overall results were satisfactory in 67%, with men having better results than women. Those with a history of injury did better than those without, and the results in those with partial or total cuff tears were better than those with intact cuffs. Since the state of the cuff affects the result, arthroscopy should precede acromioplasty.
Résumé Soixante dix-neuf patients, présentant depuis 3.5 ans (±1.8) un syndrome de conflit sousacromial, ont été traités par acromioplastie arthroscopique. Les résultats ont été évalués au moyen d'une nouvelle cotation, mesurant la symptomatologie subjective avant et 17 mois en moyenne après l'intervention chirurgicale. On a étudié le rapport entre ces résultats et la morphologie pathologique de la coiffe des rotateurs, constatée lors de l'arthroscopie et classée conformément à notre version modifiée, décrite précédemment, de la classification de Neer. Les résultats globaux étaient satisfaisants dans 67% des cas. Les résultats étaient nettement meilleurs chez les hommes que chez les femmes. Ils étaient significativement meilleurs chez les patients pour qui la symptomatologie était apparue après un traumatisme violent, de même lorsqu'il existait une rupture totale ou partielle de la coiffe des rotateurs. L'état de la coiffe influence les résultats de l'acromioplastie, pour pouvoir le déterminer il faut pratiquer une arthroscopie préalable.相似文献
998.
999.
1000.
T F Kruger J P Van der Merwe H J Odendaal F S Stander G M Grobler V A Hulme E L Erasmus K Coetzee M L Windt Y Swart 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,77(12):634-636
The results of the in vitro fertilisation programme at Tygerberg Hospital for the period April 1983 to January 1988 are presented. Of the 1117 laparoscopies performed, 825 patients reached the transfer stage. A live-birth rate of 9.3% was achieved. The pregnancy rate after transfer of 4 embryos was 25.9% compared with 15.4% after 2 embryos and 10.8% after 3 embryos (P = less than 0.0001). The multiple pregnancy rate was 2.8% in the group receiving 2 embryos and 11.7% and 10.4% in those receiving 3 and 4 embryos, respectively. Of the 77 successful pregnancies (90 babies), 1 baby died at 34 weeks' gestation as the result of abruptio placentae due to preeclampsia and 1 cot death occurred. The only congenital abnormality encountered was a cleft palate. 相似文献