全文获取类型
收费全文 | 16779篇 |
免费 | 1364篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 199篇 |
儿科学 | 495篇 |
妇产科学 | 433篇 |
基础医学 | 2288篇 |
口腔科学 | 453篇 |
临床医学 | 2069篇 |
内科学 | 3101篇 |
皮肤病学 | 217篇 |
神经病学 | 1567篇 |
特种医学 | 590篇 |
外国民族医学 | 1篇 |
外科学 | 2472篇 |
综合类 | 203篇 |
一般理论 | 12篇 |
预防医学 | 1745篇 |
眼科学 | 387篇 |
药学 | 835篇 |
中国医学 | 10篇 |
肿瘤学 | 1092篇 |
出版年
2023年 | 173篇 |
2022年 | 246篇 |
2021年 | 576篇 |
2020年 | 338篇 |
2019年 | 465篇 |
2018年 | 481篇 |
2017年 | 392篇 |
2016年 | 416篇 |
2015年 | 423篇 |
2014年 | 562篇 |
2013年 | 706篇 |
2012年 | 952篇 |
2011年 | 961篇 |
2010年 | 539篇 |
2009年 | 458篇 |
2008年 | 725篇 |
2007年 | 767篇 |
2006年 | 717篇 |
2005年 | 607篇 |
2004年 | 611篇 |
2003年 | 632篇 |
2002年 | 576篇 |
2001年 | 409篇 |
2000年 | 425篇 |
1999年 | 367篇 |
1998年 | 143篇 |
1997年 | 112篇 |
1996年 | 140篇 |
1995年 | 109篇 |
1994年 | 121篇 |
1993年 | 98篇 |
1992年 | 289篇 |
1991年 | 273篇 |
1990年 | 249篇 |
1989年 | 248篇 |
1988年 | 214篇 |
1987年 | 215篇 |
1986年 | 237篇 |
1985年 | 245篇 |
1984年 | 201篇 |
1983年 | 127篇 |
1982年 | 87篇 |
1981年 | 88篇 |
1979年 | 161篇 |
1978年 | 104篇 |
1977年 | 95篇 |
1976年 | 93篇 |
1975年 | 83篇 |
1974年 | 103篇 |
1972年 | 100篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
52.
There has been a traditional reluctance to remove a subluxed (ectopic) lens because of the high surgical risk. The use of closed intraocular microsurgical techniques, however, now allows greater intraoperative control with few complications. The authors present the results of subluxed lens extraction, by limbal or pars plana lensectomy, in 44 eyes of 24 patients, in which the indication for surgery was lens subluxation causing a reduction in visual acuity or uncorrectable refractive error. Visual acuity was improved in all cases after surgery, with no significant complications. Patients with reduced visual acuity secondary to ectopic lenses have a good visual prognosis after lensectomy using a closed intraocular microsurgical technique. 相似文献
53.
Shirley Kobar Coni C Francis Samantha MaWhinney Teresa Sharp 《Nutrition in clinical practice》2003,18(5):417-421
BACKGROUND: Development of an acclimation protocol for use when measuring resting energy expenditure (REE) would simplify and standardize data collection. The purpose of this study was to determine if our 2 metabolic carts could be used interchangeably and to determine if excluding the first 3 or 5 minutes of data collected as an acclimation period would significantly improve the coefficients of variation (CVs) for oxygen consumed (VO(2)) and carbon dioxide produced (VCO(2)) when performing REE assessments with our metabolic cart systems. METHODS: Thirteen healthy, nonsmoking adults ranging in age from 32 to 45 years, with activity levels ranging from sedentary to highly active, participated. Indirect calorimetry was performed twice in the morning after 30 minutes of supine resting. Subjects had fasted for 12 hours, and did not exercise within the last 24 hours. The system order for testing was randomized for the first measurement. When the first measurement was completed, subjects were crossed over for measurement using a second metabolic cart. RESULTS: The CVs for VO(2) and VCO(2) were significantly lower when excluding the first 3 (VO(2), p = .0005), (VCO(2), p = .0024) or 5 minutes (VO(2), p = .0001, VCO(2), p = .0021) of data compared with no exclusions. No significant differences in CVs between the 3- and 5-minute exclusions were found for VO(2) (p = .3224) or VCO(2) (p = .2255). CONCLUSIONS: Clearly, our machines cannot be used interchangeably within a study. An acclimation period improves CVs of VO(2) and VCO(2.) The similarities in CVs led us to adopt a 3-minute acclimation period for measuring REE. 相似文献
54.
55.
Justin Lee Altshuler D. M.D David Jacobs M.B.A. D. M. D. † 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》1992,4(1):12-15
There has been much interest in the in-office fabrication of ceramic posterior restorations using computer-aided design and computer-aided manufacture (CAD-CAM) units. One concern that practitioners have concerning the use of one of these systems is the initial expense of the CAD-CAM unit for the office. This article deals with the financial implications involved when considering the purchase or lease of a CEREC (CAD-CAM) unit. 相似文献
56.
57.
C L Daley P M Small G F Schecter G K Schoolnik R A McAdam W R Jacobs P C Hopewell 《The New England journal of medicine》1992,326(4):231-235
BACKGROUND. Tuberculosis typically develops from a reactivation of latent infection. Clinical tuberculosis may also arise from a primary infection, and this is thought to be more likely in persons infected with the human immunodeficiency virus (HIV). However, the relative importance of these two pathogenetic mechanisms in this population is unclear. METHODS. Between December 1990 and April 1991, tuberculosis was diagnosed in 12 residents of a housing facility for HIV-infected persons. In the preceding six months, two patients being treated for tuberculosis had been admitted to the facility. We investigated this outbreak using standard procedures plus analysis of the cultured organisms with restriction-fragment-length polymorphisms (RFLPs). RESULTS. Organisms isolated from all 11 of the culture-positive residents had similar RFLP patterns, whereas the isolates from the 2 patients treated for tuberculosis in the previous six months were different strains. This implicated the first of the 12 patients with tuberculosis as the source of this outbreak. Among the 30 residents exposed to possible infection, active tuberculosis developed in 11 (37 percent), and 4 others (13 percent) had newly positive tuberculin skin tests. Of 28 staff members with possible exposure, at least 6 had positive tuberculin-test reactions, but none had tuberculosis. CONCLUSIONS. Newly acquired tuberculous infection in HIV-infected patients can spread readily and progress rapidly to active disease. There should be heightened surveillance for tuberculosis in facilities where HIV-infected persons live, and investigation of contacts must be undertaken promptly and be focused more broadly than is usual. 相似文献
58.
Dr. Joseph A. Kuhn MD Lawrence D. Wagman MD John A. Lorant MD Fredrick W. Grannis MD Mordecai Dunst MD William R. Dougherty MD Daniel I. Jacobs MD 《Annals of surgical oncology》1994,1(4):353-359
Background: A radical forequarter amputation with partial chest wall resection (one to four ribs) has been reported for benign and malignant
lesions involving the shoulder and chest wall region. Concerns about reconstruction and postoperative pulmonary function have
previously limited more extensive chest wall resections. The current report describes the first case in which a complete unilateral
anterior and posterior chest wall resection and pneumonectomy (hemithoracectomy) accompany a forequarter amputation. A novel
reconstructive technique used the full circumference of the forearm tissue with an intact ulna as a free osseomyocutaneous
flap.
Methods: In this case, a 21-year-old patient presented with an extensive recurrent desmoid tumor that involved the shoulder, brachial
plexus, subclavian vein, and chest wall from the lateral sternal border to the midportion of the scapula and down to the eighth
rib. The operative technique involved removal of the entire right hemithorax from the midline sternum to the transverse process
posteriorly, down to the ninth rib inferiorly. Due to the absence of a rigid hemithorax, the uninvolved ipsilateral lung was
also removed. The forearm flap was prepared before final separation of the specimen and division of the subclavian vessels.
Results: Postoperatively, the patient maintained excellent oxygenation without atelectasis or fever and was extubated on the 15th
postoperative day. As expected after pneumonectomy, significant decreases from preoperative to immediate postoperative values
were noted for the vital capacity (VC) (from 4.87 L to 1.29 L), forced 1-s expiratory volume (FEV1) (from 3.77 L to 1.02 L),
and inspiratory capacity (IC) (3.33 1 to 0.99 1). Rehabilitation included a specially designed external prosthesis to provide
cosmesis and prevent scoliosis. By the 15th postoperative week the patient had returned to normal social and physical activities,
with a gradual improvement in all respiratory parameters: VC 1.52 L, FEV1 1.29 L, IC 1.04 L. There has been no evidence of
tumor recurrence at 1 year.
Conclusions: This report provides evidence that a complete hemithoracectomy, pneumonectomy, and forequarter amputation can be safely performed
for selective tumors involving the shoulder region with extensive chest wall invasion. Reconstruction may be achieved with
an extended forearm osseomyocutaneous free flap with an excellent functional outcome.
Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993. 相似文献
59.
R L Becker J F Norfray G P Teitelbaum W G Bradley J B Jacobs L Wacaser R L Rieman 《AJNR. American journal of neuroradiology》1988,9(5):885-889
Four patients with intracranial aneurysm clips made from a variety of alloys were studied without incidence by MR imaging at field strengths ranging from 0.35 to 0.6 T. Knowledge of the type of alloy used in the manufacturing of an aneurysm clip is important in determining whether the clip will or will not deflect in a magnetic field. Ferromagnetic clips show deflection and torque in a magnetic field and have the potential to dislodge from the aneurysm. Nonferromagnetic or weakly ferromagnetic aneurysm clips such as the Sugita (Elgiloy), Yasargil (316 LVM stainless steel), Heifetz (Elgiloy), Yasargil (Phynox), and Vari-Angle McFadden (MP35N) do not deflect or deflect weakly in the magnetic field and therefore would not be expected to dislodge during MR. The option of imaging many patients with intracranial aneurysm clips with MR extends the usefulness of the technique to a previously excluded population. 相似文献
60.
J W Jacobs 《American journal of psychotherapy》1988,42(2):308-319
Analysis of Euripides' play, Medea, and a divorcing family suggests that divorce between a narcissistically scarred, embittered, dependent woman and a pathologically narcissistic, devaluing man may lead to the mother's attempt to sever father-child contact as a means of revenging the injury inflicted on her by the loss of a selfobject, her hero-husband. 相似文献