全文获取类型
收费全文 | 32608篇 |
免费 | 2535篇 |
国内免费 | 125篇 |
专业分类
耳鼻咽喉 | 292篇 |
儿科学 | 874篇 |
妇产科学 | 665篇 |
基础医学 | 3818篇 |
口腔科学 | 934篇 |
临床医学 | 3974篇 |
内科学 | 6986篇 |
皮肤病学 | 441篇 |
神经病学 | 3050篇 |
特种医学 | 1225篇 |
外科学 | 3599篇 |
综合类 | 314篇 |
一般理论 | 31篇 |
预防医学 | 3345篇 |
眼科学 | 755篇 |
药学 | 2575篇 |
中国医学 | 43篇 |
肿瘤学 | 2347篇 |
出版年
2023年 | 257篇 |
2022年 | 250篇 |
2021年 | 488篇 |
2020年 | 460篇 |
2019年 | 501篇 |
2018年 | 706篇 |
2017年 | 606篇 |
2016年 | 629篇 |
2015年 | 714篇 |
2014年 | 1035篇 |
2013年 | 1574篇 |
2012年 | 2028篇 |
2011年 | 2152篇 |
2010年 | 1295篇 |
2009年 | 1409篇 |
2008年 | 2099篇 |
2007年 | 2300篇 |
2006年 | 2308篇 |
2005年 | 2225篇 |
2004年 | 2172篇 |
2003年 | 2054篇 |
2002年 | 2004篇 |
2001年 | 322篇 |
2000年 | 223篇 |
1999年 | 344篇 |
1998年 | 476篇 |
1997年 | 389篇 |
1996年 | 368篇 |
1995年 | 324篇 |
1994年 | 295篇 |
1993年 | 278篇 |
1992年 | 162篇 |
1991年 | 183篇 |
1990年 | 149篇 |
1989年 | 143篇 |
1988年 | 130篇 |
1987年 | 138篇 |
1986年 | 115篇 |
1985年 | 161篇 |
1984年 | 214篇 |
1983年 | 163篇 |
1982年 | 243篇 |
1981年 | 244篇 |
1980年 | 232篇 |
1979年 | 109篇 |
1978年 | 106篇 |
1977年 | 106篇 |
1976年 | 82篇 |
1975年 | 70篇 |
1974年 | 63篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Brian Wm. Davies M.D. Gary A. Pennington M.D. Bahman Guyuron M.D. 《Aesthetic plastic surgery》1993,17(2):125-128
Ambulatory surgery has become routine for many plastic surgery procedures. Anesthesia techniques including general anesthesia by inhalation and intravenous infusion and the dissociative technique have all been used successfully for outpatient anesthesia. Propofol (Diprivan), a relatively new agent, has proven to be a safe and effective general anesthesia agent for outpatient surgery. We report on our experience with propofol as an induction agent and continuous drip for general anesthesia maintenance in 100 consecutive outpatient, plastic surgery procedures performed in an office facility. Assessment factors were recovery-room time, nausea and vomiting in the recovery room and at home, hallucinations, patients' recollection of anesthesia experience, and overall patient satisfaction. 相似文献
42.
Harold A. Williamson Jr. MD MSPH L. Gary Hart PhD Michael J. Pirani Roger A. Rosenblatt MD MPH 《The Journal of rural health》1994,10(1):16-25
Surgical services are an important part of modern health care, but providing them to isolated rural citizens is especially difficult. Public policy initiatives could influence the supply, training, and distribution of surgeons, much as they have for rural primary care providers. However, so little is known about the proper distribution of surgeons, their contribution to rural health care, and the safety of rural surgery that policy cannot be shaped with confidence. This study examined the volume and complexity of inpatient surgery in rural Washington state as a first step toward a better understanding of the current status of rural surgical services. Information about rural surgical providers was obtained through telephone interviews with administrators at Washington's 42 rural hospitals. The Washington State Department of Health's Commission Hospital Abstract Recording System (CHARS) data provided a count of the annual surgical admissions at rural hospitals. Diagnosis-related group (DRG) weights were used to measure complexity of rural surgical cases. Surgical volume varied greatly among hospitals, even among those with a similar mix of surgical providers. Many hospitals provided a limited set of basic surgical services, while some performed more complex procedures. None of these rural hospitals could be considered high volume when compared to volumes at Seattle hospitals or to research reference criteria that have assessed volume-outcome relationships for surgical procedures. Several hospitals had very low volumes for some complex procedures, raising a question about the safety of performing them. The leaders of small rural hospitals must recognize not only the fiscal and service benefits of surgical services--and these are considerable--but also the potentially adverse effect of low surgical volume on patient outcomes. Policies that encourage the proper training and distribution of surgeons, the retention of basic rural surgical services, and the rational regionalization of complex surgery are likely to enhance the convenience and safety of surgery for rural citizens. 相似文献
43.
Background : It is well known that reoperation for recurrent coronary artery disease is more difficult than primary coronary artery bypass grafting. However, it is possible to reduce the morbidity and mortality of reoperation to the same level as the initial procedure with careful surgical technique. Methods : A retrospective study of the first 200 patients who underwent redo coronary bypass grafting was undertaken. Results : In the first 200 cases of redo coronary bypass grafting at St George Hospital, Sydney (August 1986–January 1995), there were five in-hospital deaths (2.5%). There was one case of sternal infection (0.5%), which required surgical debridement, three cases of stroke (1.5%), one case of postoperative bleeding (0.5%), which required a return to theatre and six cases (3%) required mechanical ventilation for more than 24h. The need for major postoperative support (such as intra-aortic balloon pumping/adrenaline infusion) was significantly affected by the degree of urgency and the degree of pre-operative ventricular impairment. Conclusions : The mortality rate of redo coronary artery bypass grafting in this series is similar to that of primary surgery described in other reports. 相似文献
44.
Robert C Susil Kevin Camphausen Peter Choyke Elliot R McVeigh Gary S Gustafson Holly Ning Robert W Miller Ergin Atalar C Norman Coleman Cynthia Ménard 《Magnetic resonance in medicine》2004,52(3):683-687
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized. 相似文献
45.
Takahisa Okano Matthew D. Horton Gary G. Fermanis David A. Horton 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):437-439
We report a re-do case of severe aortic valve stenosis due to pannus formation 29 years after an aortic Starr-Edwards caged-ball
valve implantation. A huge shelf of calcified and thick pannus tissue below the valve had reduced the already small orifice
by at least a third in surface area. The explanted Starr-Edwards valve revealed no mechanical or structural failure. Early
detection and treatment of pannus outgrowth is essential in order to prevent life-threatening prosthetic valve malfunctions. 相似文献
46.
Kathryn E Arnold Jody L Schweitzer Barbara Wallace Monique Salter Ruth Neeman W Gary Hlady Bernard Beall 《Infection control and hospital epidemiology》2006,27(12):1377-1384
OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs. 相似文献
47.
48.
John P Elliott Niki B Istwan Ann Collins Debbie Rhea Gary Stanziano 《Journal of perinatology》2005,25(1):4-7
OBJECTIVE: To identify the etiology and impact of preterm delivery in twin gestations. STUDY DESIGN: Twin gestations delivered at 33.0 to 36.9 weeks were identified in a perinatal database, and categorized by indication for delivery. Deliveries were identified as indicated, or non-indicated (discretionary). Neonatal outcomes were measured by birth weight, length of stay, NICU admission, and ventilator utilization. Data were divided and analyzed by indicated or discretionary delivery, and gestational age at delivery. RESULTS: Analyzed were 3252 twin gestations (6504 infants), with 78% having indicated delivery. Of the 22% with discretionary delivery, nearly 40% required NICU admission. With each advancing week of gestation, there was a significant decrease in incidence of NICU admission and nursery days. CONCLUSION: The majority of preterm deliveries were indicated, though 22% were discretionary. It is vital to consider neonatal morbidity and costs related to gestational age when choosing discretionary delivery. 相似文献
49.
Gary Coleman Tom A. Gardiner Ariel Boutaud Alan W. Stitt 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(4):581-587
Background A recombinant form of the α2(IV)NC1 domain of type IV collagen has been shown to have potent anti-angiogenic activity although
this peptide has not been studied in the context of proliferative retinopathies. In the current investigation we examined
the potential for α2(IV)NC1 to regulate retinal microvascular endothelial cell function using a range of in vitro and in vivo
assay systems.
Materials and methods α2(IV)NC1 at concentrations between 0.1 and 1 μg/ml was added to retinal microvascular endothelial cells (RMECs) followed
by assessment of cell attachment, proliferation and survival. This agent was also tested within a novel in vitro three-dimensional
retinal angiogenesis assay and the number of angiogenic sprouts quantified. α2(IV)NC1 was also delivered intra-vitreally to
mice with oxygen-induced proliferative retinopathy (OIR) and neovascularisation evaluated in comparison with vehicle-treated
controls.
Results RMECs treated with α2(IV)NC1 (0.1, 0.5 and 1 μg/ml) showed delayed attachment at 3 h post-seeding, although this deficit had
been restored at the 6-h time point. BrdU assay of DNA replication revealed that confluent RMECs treated with α2(IV)NC1 showed
no measurable response in comparison with vehicle-treated controls. By contrast, proliferation of sub-confluent RMECs was
significantly reduced by α2(IV)NC1 at 0.5 μg/ml (P<0.01). α2(IV)NC1 also induced apoptosis in RMECs and inhibited angiogenesis of pre-existing retinal vascular networks in
vitro (P<0.001). Intra-vitreal injection of α2(IV)NC1 in the OIR model significantly inhibited pre-retinal neovascularisation compared
with vehicle-treated controls (P<0.001).
Conclusion α2(IV)NC1 inhibits angiogenesis in the retinal microvasculature. This recombinant protein has potential for the treatment
of neovascularisation in proliferative retinopathies.
BioStratum Inc. did not sponsor this research in any way. None of the authors are paid consultants with this company. 相似文献
50.