全文获取类型
收费全文 | 70832篇 |
免费 | 5282篇 |
国内免费 | 476篇 |
专业分类
耳鼻咽喉 | 816篇 |
儿科学 | 1887篇 |
妇产科学 | 1547篇 |
基础医学 | 8940篇 |
口腔科学 | 1247篇 |
临床医学 | 7054篇 |
内科学 | 16046篇 |
皮肤病学 | 1388篇 |
神经病学 | 5591篇 |
特种医学 | 2327篇 |
外国民族医学 | 1篇 |
外科学 | 9843篇 |
综合类 | 1618篇 |
一般理论 | 48篇 |
预防医学 | 4829篇 |
眼科学 | 2325篇 |
药学 | 5276篇 |
1篇 | |
中国医学 | 365篇 |
肿瘤学 | 5441篇 |
出版年
2023年 | 388篇 |
2022年 | 629篇 |
2021年 | 1566篇 |
2020年 | 987篇 |
2019年 | 1381篇 |
2018年 | 1715篇 |
2017年 | 1295篇 |
2016年 | 1449篇 |
2015年 | 1681篇 |
2014年 | 2383篇 |
2013年 | 3135篇 |
2012年 | 4602篇 |
2011年 | 4786篇 |
2010年 | 2710篇 |
2009年 | 2423篇 |
2008年 | 4168篇 |
2007年 | 4476篇 |
2006年 | 4522篇 |
2005年 | 4381篇 |
2004年 | 4102篇 |
2003年 | 3885篇 |
2002年 | 3667篇 |
2001年 | 1382篇 |
2000年 | 1241篇 |
1999年 | 1225篇 |
1998年 | 845篇 |
1997年 | 647篇 |
1996年 | 608篇 |
1995年 | 542篇 |
1994年 | 502篇 |
1993年 | 465篇 |
1992年 | 667篇 |
1991年 | 604篇 |
1990年 | 579篇 |
1989年 | 545篇 |
1988年 | 499篇 |
1987年 | 536篇 |
1986年 | 461篇 |
1985年 | 442篇 |
1984年 | 474篇 |
1983年 | 389篇 |
1982年 | 428篇 |
1981年 | 367篇 |
1980年 | 345篇 |
1979年 | 254篇 |
1978年 | 251篇 |
1977年 | 227篇 |
1976年 | 222篇 |
1975年 | 186篇 |
1974年 | 155篇 |
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
81.
Susan W. Volk VMD PhD ; Antoneta Radu BS ; Liping Zhang MS ; Kenneth W. Liechty MD 《Wound repair and regeneration》2007,15(5):736-747
Chronic wounds create a formidable clinical problem resulting in considerable morbidity and healthcare expenditure. The etiology for wound healing impairment appears to be multifactorial; however, ischemia is a common factor in most types of chronic wounds. Ideal therapy for such wounds would be to correct deficiencies in growth factors and matrix components and provide cellular precursors required for timely wound closure. We hypothesized that stromal progenitor cell (SPC) therapy could correct the ischemic wound-healing defect through both direct and indirect mechanisms. To test this hypothesis, we used the ischemic rabbit ear model of chronic wound healing. We found that treatment of the wounds with SPCs was able to reverse the ischemic wound-healing impairment, with improved granulation tissue formation and reepithelialization compared with vehicle or bone marrow mononuclear cell controls. In vitro, SPCs were found to produce factors involved in angiogenesis and reepithelialization, and extracellular matrix components, providing evidence for both direct and indirect mechanisms for the observed correction of the healing impairment in these wounds. Treatment of ischemic wounds with SPCs can dramatically improve wound healing and provides a rationale for further studies focused on SPCs as a potential cellular therapy in impaired wound healing. 相似文献
82.
83.
Many people die in emergency departments (EDs) across the United States from sudden illnesses or injuries, an exacerbation of a chronic disease, or a terminal illness. Frequently, patients and families come to the ED seeking lifesaving or life-prolonging treatment. In addition, the ED is a place of transition-patients usually are transferred to an inpatient unit, transferred to another hospital, or discharged home. Rarely are patients supposed to remain in the ED. Currently, there is an increasing amount of literature related to end-of-life care. However, these end-of-life care models are based on chronic disease trajectories and have difficulty accommodating sudden-death trajectories common in the ED. There is very little information about end-of-life care in the ED. This article explores ED culture and characteristics, and examines the applicability of current end-of-life care models. 相似文献
84.
Four-Year Follow-up on Endovascular Radiofrequency Obliteration of Great Saphenous Reflux 总被引:4,自引:0,他引:4
Merchant Robert F. MD Pichot Olivier MD † Myers Kenneth A. MD ‡ 《Dermatologic surgery》2005,31(2):129-134
BACKGROUND: Endovascular radiofrequency obliteration has been used since 1998 as an alternative to conventional vein stripping surgery for elimination of saphenous vein insufficiency. OBJECTIVE: To demonstrate the long-term efficacy of this treatment modality. METHODS: Data were prospectively collected in a multicenter ongoing registry. Only great saphenous vein above-knee treatments were included in this study. Eight hundred ninety patients (1,078 limbs) were treated prior to November 2003 at 32 centers. Clinical and duplex ultrasound follow-up was performed at 1 week, 6 months, and 1, 2, 3, and 4 years. RESULTS: Among 1,078 limbs treated, 858 were available for follow-up within 1 week, 446 at 6 months, 384 at 1 year, 210 at 2 years, 114 at 3 years, and 98 at 4 years. The vein occlusion rates were 91.0%, 88.8%, 86.2%, 84.2%, and 88.8%, respectively; the reflux-free rates were 91.0%, 89.3%, 86.2%, 86.0%, and 85.7%, respectively; and the varicose vein recurrence rates were 7.2%, 13.5%, 17.1%, 14.0%, and 21.4%, respectively, at each follow-up time point at 6 months, and 1, 2, 3, and 4 years. Patient symptom improvement persisted over 4 years. CONCLUSIONS: Endovascular temperature-controlled radiofrequency obliteration of saphenous vein reflux exhibits an enduring treatment efficacy clinically, anatomically, and hemodynamically up to 4 years following treatment. 相似文献
85.
It's all about sex: gender, lung development and lung disease. 总被引:1,自引:0,他引:1
Michelle A Carey Jeffrey W Card James W Voltz Samuel J Arbes Dori R Germolec Kenneth S Korach Darryl C Zeldin 《Trends in Endocrinology and Metabolism》2007,18(8):308-313
Accumulating evidence suggests that gender affects the incidence, susceptibility and severity of several lung diseases. Gender also influences lung development and physiology. Data from both human and animal studies indicate that sex hormones might contribute to disease pathogenesis or serve as protective factors, depending on the disease involved. In this review, the influence of gender and sex hormones on lung development and pathology will be discussed, with specific emphasis on pulmonary fibrosis, asthma and cancer. 相似文献
86.
Fahim Zaman Atta Nawabi Kenneth D Abreo Gazi B Zibari 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(3):262-265
Laparoscopic procedures continue to gain popularity over traditional open procedures for a number of abdominal and pelvic surgeries. With increasing experience, the application of this technique is rising because it provides an alternative, less invasive, approach to various surgical procedures. Herein, we report our experience with adult patients with polycystic kidney disease, requiring bilateral laparoscopic nephrectomy before renal transplantation. 相似文献
87.
Donald B. Penzien PhD ; Frank Andrasik PhD ; Brian M. Freidenberg PhD ; Timothy T. Houle PhD ; Alvin E. Lake III PhD; Gay L. Lipchik PhD ; Kenneth A. Holroyd PhD ; Richard B. Lipton MD ; Douglas C. McCrory MD ; Justin M. Nash PhD ; Robert A. Nicholson PhD ; Scott W. Powers PhD ABPP ; Jeanetta C. Rains PhD ; David A. Wittrock PhD 《Headache》2005,45(S2):S110-S132
Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache. 相似文献
88.
What factors influence survival in patients with unresected synchronous liver metastases after resection of colorectal cancer? 总被引:3,自引:0,他引:3
N. Chafai C. L. H. Chan E. L. Bokey O. F. Dent G. Sinclair P. H. Chapuis 《Colorectal disease》2005,7(2):176-181
OBJECTIVE: The aim of this study was to determine whether the survival of patients with untreated synchronous liver metastases after resection of a colorectal cancer was associated with any features of the primary tumour. METHODS: Information for 398 consecutive patients with unresected liver metastases in the period 1971-2001 was examined by multivariate survival analysis. RESULTS: Of 19 clinical and pathological variables considered, survival was independently associated only with residual tumour in a line of resection (hazard ratio (HR) 1.95), venous invasion (HR 1.87), right colonic tumour (HR 1.68), lymph node metastasis (HR 1.54), and extra-hepatic metastasis (HR 1.16); 8.3% of patients had none of these adverse features. Their 2-year overall survival rate was 39.2%, compared with only 16.5% (P < 0.001) in those with one or more adverse features. CONCLUSIONS: These findings may assist in selecting patients most likely to benefit from treatment of hepatic metastases and in counselling patients and their relatives. 相似文献
89.
90.
Kenneth M. Flegel 《Canadian Medical Association journal》2005,173(10):1213-1214