全文获取类型
收费全文 | 761篇 |
免费 | 49篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 97篇 |
妇产科学 | 2篇 |
基础医学 | 47篇 |
口腔科学 | 17篇 |
临床医学 | 77篇 |
内科学 | 116篇 |
皮肤病学 | 6篇 |
神经病学 | 12篇 |
特种医学 | 185篇 |
外科学 | 79篇 |
综合类 | 47篇 |
预防医学 | 18篇 |
眼科学 | 5篇 |
药学 | 36篇 |
1篇 | |
肿瘤学 | 77篇 |
出版年
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 12篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 17篇 |
2011年 | 14篇 |
2010年 | 15篇 |
2009年 | 12篇 |
2008年 | 16篇 |
2007年 | 22篇 |
2006年 | 26篇 |
2005年 | 19篇 |
2004年 | 17篇 |
2003年 | 18篇 |
2002年 | 11篇 |
2001年 | 24篇 |
2000年 | 8篇 |
1999年 | 14篇 |
1998年 | 26篇 |
1997年 | 24篇 |
1996年 | 20篇 |
1995年 | 25篇 |
1994年 | 25篇 |
1993年 | 36篇 |
1992年 | 15篇 |
1991年 | 11篇 |
1990年 | 17篇 |
1989年 | 24篇 |
1988年 | 30篇 |
1987年 | 47篇 |
1986年 | 37篇 |
1985年 | 30篇 |
1984年 | 16篇 |
1983年 | 23篇 |
1982年 | 12篇 |
1981年 | 19篇 |
1980年 | 13篇 |
1979年 | 16篇 |
1978年 | 18篇 |
1977年 | 9篇 |
1976年 | 4篇 |
1975年 | 8篇 |
1974年 | 5篇 |
1933年 | 2篇 |
排序方式: 共有823条查询结果,搜索用时 15 毫秒
21.
Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate 总被引:1,自引:0,他引:1
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A. 相似文献
22.
B H Wilson H W Severance M P Raney J C Pressley R A McKinnis M C Hindman M Smith G S Wagner 《The American journal of cardiology》1984,53(1):68-70
The outcome in 126 consecutive patients with nontraumatic out-of-hospital cardiac arrest was analyzed to determine the effectiveness of a standard ambulance system over 22 months. Therapy was limited to basic life support (that is, administration of oxygen by mask, i.v. fluids, closed-chest massage and artificial respiration) by emergency medical technicians in a community in which less than 1% of the population had been trained in cardiopulmonary resuscitation (CPR). Analyses of patient data were performed to determine the relations between survival to hospital admission or discharge and 6 variables; response time, prior CPR, initial rhythm, acute myocardial infarction, initial blood pressure and initial pulse. Of 126 patients, 28 (22%) survived to hospital admission and 11 (9%) to hospital discharge. Two patient subgroups had a higher discharge rate: those with an initial rhythm of ventricular tachycardia or fibrillation (7 of 50, 14%), and those with an initial blood pressure greater than or equal to 90 mm Hg and a pulse rate of greater than 50 beats/min (3 of 6, 50%). For patients in arrest before ambulance arrival, there was no difference in outcome between those who did or those who did not receive prior CPR. Results of this study can be used as a basis for evaluating and comparing interventions directed toward stabilization of patients during the prehospital phase of cardiac arrest. 相似文献
23.
Abstract Background: One of the unique variables for successful implantation of transcatheter aortic valves involves the ability to secure an access route for deployment of the aortic valve. Aim of study: A large number of the high‐risk patients with critical aortic stenosis referred for transcatheter valve implantation approach may not be candidates for the femoral approach due to peripheral vascular disease with the morbidity and mortality increased severalfold in patients who develop access related complications. Method & Results: A thorough knowledge and review of various alternate access site techniques and trouble shooting are therefore important and required by the implanting cardiac surgeons involved in transcatheter aortic valve therapy. Conclusion: The article review highlights the various percutaneous, hybrid, and surgical access techniques platforms available as well as options for implantation of these devices . (J Card Surg 2010;25:373‐380) 相似文献
24.
25.
26.
Monica Matus-Ridley R. Beverly Raney Hasina Thawerani Anna T. Meadows 《Pediatric blood & cancer》1983,11(2):99-105
The pathologic materials and clinical courses of 36 children aged 1 month-22 years, with histiocytosis × (H-X) seen at the Philadelphia Children's Cancer Research Center from 1970 to 1979 were reviewed. The pathologic subtype of H-X was favorable (type II) in 31 patients, unfavorable (type I) in one patient, and unclassified in four patients whose specimens were limited to a skin biopsy. Sixteen patients had localized H-X involving bone (14 patients), soft tissue (1 patient), or skin only (1 patient); all are alive and well after treatment with surgery alone (12 patients), radiation therapy (RT) (3 patients), or observation (1 patient); only 1 of the 16 developed recurrent H-X. The other 20 patients presented with multifocal H-X involving the skeleton alone (3 patients); the skeleton and soft tissues other than liver (7 patients); soft tissue exclusive of the liver (3 patients); soft tissue including the liver (4 patients); or soft tissues, skeleton, and liver or multiple drugs ± RT (15 patients). Seven of the 20 patients are alive and well without recurrence at a median of 4 years after diagnosis. Nine of the 20 patients, including 3 with liver dysfunction, responded completely to initial therapy but developed recurrence; each was retreated with drugs and is alive and well at a median of 4 years. The remaining 4 patients had widespread disease with dysfunction of the liver and/or hematopoietic system at diagnosis, failed to respond, and died. We conclude that (1) patients with multiple bony lesions with or without associated soft tissue disease or skin involvement have a favorable outlook and do not require systemic chemotherapy; (2) systemic treatment also is unnecessary for patients with localized H-X since recurrence is rare; (3) drugs can benefit patients with multifocal H-X, although the optimal duration of therapy is unclear; and (4) favorable response to treatment indicates high probability of disease-free survival. However, organ dysfunction at diagnosis is ominous: four of seven patients with liver dysfunction are dead, as are all three patients who prsented with peripheral blood count depression. 相似文献
27.
Tang RB Wang HY Lu HY Xiong J Li HH Qiu XH Liu HQ 《第二军医大学学报》2005,26(8):880-880
There have been extensive observations that RNA containing repetitive elements accumulates in transformed cells and tumor tissues. In the present study, we first obtained result consistent with previous observations by in situ hybridization. 相似文献
28.
Richard Beverly Raney Jane Meza James R. Anderson Christopher J. Fryer Sarah S. Donaldson John C. Breneman Thomas J. Fitzgerald Edmund A. Gehan Jeff M. Michalski Jorge A. Ortega Stephen J. Qualman Eric Sandler Moody D. Wharam Eugene S. Wiener Harold M. Maurer William M. Crist 《Pediatric blood & cancer》2002,38(1):22-32
29.
Manon Auger Beverly Raney David Callender Patricia Eifel Nelson G. Ord ez 《Fetal and pediatric pathology》1994,14(5):763-770
A 27-month-old boy of Hispanic background developed multiple cranial nerve palsies, difficulty swallowing, bloody nasal discharge, and irritability. Radiographic evaluations showed extensive destruction of the clivus by a large tumor that invaded the sphenoid bone, left cavernous sinus, ethmoid sinus, nasal cavity, and left orbit. Multiple pulmonary nodules were also noted. The bone marrow and spinal fluid showed no evident tumor cells. Transnasal biopsy revealed a chordoma. Treatment was initiated with a combination of ifosfamide, mesna, and etoposide along with radiation therapy to the cranial tumor. Shifting pulmonary densities were noted on serial films. Despite some clinical improvement, the child developed rapidly progressive hypoxemia 3 weeks after admission and died. Autopsy showed persistent viable tumor in the primary site and massive pulmonary arteriolar tumor emboli, infarcts, and widespread lung parenchymal metastases. No other sites of tumor involvement were discovered. This is the second child reported with intracranial chordoma, pulmonary metastases at diagnosis, and early death attributed to pulmonary tumor emboli. 相似文献
30.
Early pregnancy complications: endovaginal sonographic findings correlated with human chorionic gonadotropin levels 总被引:2,自引:0,他引:2
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L. 相似文献