全文获取类型
收费全文 | 15859篇 |
免费 | 965篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 208篇 |
儿科学 | 467篇 |
妇产科学 | 261篇 |
基础医学 | 1766篇 |
口腔科学 | 556篇 |
临床医学 | 1306篇 |
内科学 | 3526篇 |
皮肤病学 | 388篇 |
神经病学 | 896篇 |
特种医学 | 468篇 |
外国民族医学 | 5篇 |
外科学 | 2319篇 |
综合类 | 431篇 |
一般理论 | 12篇 |
预防医学 | 1112篇 |
眼科学 | 504篇 |
药学 | 1502篇 |
1篇 | |
中国医学 | 178篇 |
肿瘤学 | 995篇 |
出版年
2023年 | 187篇 |
2022年 | 524篇 |
2021年 | 791篇 |
2020年 | 459篇 |
2019年 | 649篇 |
2018年 | 690篇 |
2017年 | 433篇 |
2016年 | 550篇 |
2015年 | 565篇 |
2014年 | 707篇 |
2013年 | 875篇 |
2012年 | 1245篇 |
2011年 | 1228篇 |
2010年 | 773篇 |
2009年 | 541篇 |
2008年 | 824篇 |
2007年 | 842篇 |
2006年 | 737篇 |
2005年 | 685篇 |
2004年 | 558篇 |
2003年 | 456篇 |
2002年 | 405篇 |
2001年 | 221篇 |
2000年 | 204篇 |
1999年 | 191篇 |
1998年 | 89篇 |
1997年 | 62篇 |
1996年 | 52篇 |
1995年 | 52篇 |
1994年 | 54篇 |
1993年 | 54篇 |
1992年 | 87篇 |
1991年 | 108篇 |
1990年 | 94篇 |
1989年 | 107篇 |
1988年 | 68篇 |
1987年 | 78篇 |
1986年 | 60篇 |
1985年 | 60篇 |
1984年 | 47篇 |
1983年 | 31篇 |
1981年 | 37篇 |
1980年 | 30篇 |
1979年 | 54篇 |
1978年 | 30篇 |
1977年 | 26篇 |
1975年 | 32篇 |
1974年 | 28篇 |
1973年 | 24篇 |
1969年 | 28篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Propofol versus traditional sedative agents for gastrointestinal endoscopy: a meta-analysis. 总被引:6,自引:0,他引:6
Mohammed A Qadeer John J Vargo Farah Khandwala Rocio Lopez Gregory Zuccaro 《Clinical gastroenterology and hepatology》2005,3(11):1049-1056
BACKGROUND & AIMS: Even though propofol has better recovery profile than traditional agents, its use is limited because of the perception of increased complication rates. Because an adequately powered trial comparing risk of propofol with traditional agents is lacking, we performed a meta-analysis of the current literature. METHODS: We searched Medline (1966-October 2004), EMBASE (1980-October 2004), and Cochrane controlled trials registry. The following 4 cardiopulmonary complications were assessed: hypoxia, hypotension, arrhythmias, and apnea. Procedures were divided into 3 groups: esophagogastroduodenoscopy group, colonoscopy group, and endoscopic retrograde cholangiopancreatography/endoscopic ultrasonography group. Pooled odds ratios for complications were calculated for all the procedures combined and then separately for the 3 groups. Random effects models were used for 2-proportion comparisons. RESULTS: Of the 90 citations identified, 12 original studies qualified for this meta-analysis and included 1161 patients. Of these, 634 received propofol, and 527 received midazolam, meperidine, and/or fentanyl. Most of the included studies were randomized trials of moderate quality and nonsignificant heterogeneity (Cochran Q = 4.81, P = .90). Compared with traditional sedative agents, the pooled odds ratio with the use of propofol for developing hypoxia or hypotension for all the procedures combined was 0.74 (95% confidence interval [CI], 0.44-1.24); for EGD, 0.85 (95% CI, 0.33-2.17); for colonoscopy, 0.4 (95% CI, 0.2-0.79); and for ERCP/EUS, 1.07 (95% CI, 0.38-3.01). CONCLUSIONS: Propofol sedation during colonoscopy appears to have lower odds of cardiopulmonary complications compared with traditional agents, but for other procedures, the risk of complications is similar. 相似文献
22.
Andreas Granetzny Ashraf Hatem Alaa Shalaby Ahmad Boseila 《European journal of cardio-thoracic surgery》2005,27(3):361-366
OBJECTIVE: In a prospective study, the effect of thymectomy on the pulmonary status of 50 consecutive patients with myasthenia gravis was evaluated over a time range of 4 years in the Chest and Chest surgery departments in the Cairo University Clinics and Thoracic Surgery Department of the Evangelisches Krankenhaus Duisburg-Nord. METHODS: The patients were divided into two groups: Group I included 26 patients who underwent thymectomy through median sternotomy. The mean age of the patients in this group was 24.8+/-10.5 (5-41) years. They were 19 females and seven males. Thirteen of the patients were in Myasthenia Gravis Foundation of America (MGFA) class IIa, and 12 were in class IIb, and one was in class IIIa. Group II included 24 patients who underwent thymectomy through manubriotomy. The mean age of the patients in this group was 25.2+/-9.2 (12-41) years. They were 13 females and 11 males. Eight of the patients were in MGFA class 2a, 14 were in class IIb, and two were in class IIIa. RESULTS: When compared to group I in which postoperative ventilation was required in 15.4% of patients, postoperative ventilation was not necessary in patients of group II with a statistically significant difference (P=0.04). The mean duration of stay in the intensive care unit was 111.4h in group II, and 169.7h in group I (P=0.03). The peak inspiratory flow rate and the forced vital capacity were also statistically significantly better in group II. There was no mortality in both groups, and the morbidity was higher in the median sternotomy group. CONCLUSION: Thymectomy through a manubriotomy, which allows extensive removal of ectopic thymic tissue in addition to the thymus through a less invasive approach than a full median sternotomy, is associated with a significantly smoother postoperative course and less pulmonary complications, when compared with thymectomy through a full median sternotomy. 相似文献
23.
Ahmad Y. Sheikh MD ; Mark D. Rollins MD PhD ; Harriet W. Hopf MD ; Thomas K. Hunt MD 《Wound repair and regeneration》2005,13(3):303-308
There is a need for a noninvasive method that measures wound angiogenesis. Hyperoxia is known to increase the appearance of new blood vessels in wounds, yet no study has confirmed increases in wound bed perfusion with periodic hyperbaric oxygen (HBO) exposure. This study investigates whether laser Doppler imaging is able to detect and quantify the enhancement of wound angiogenesis that is known to occur with intermittent HBO treatments. Full-thickness dorsal dermal wounds were created on mice randomized to hyperoxic (n = 14) and control (n = 15) groups. Hyperbaric oxygen was administered twice daily for 90 minutes each at 2.1 atmospheres for 7 days. Wound bed perfusion was measured by laser Doppler imaging on days 0, 7, and 10 postwounding. Wound blood flow increased significantly over baseline on day 7 and 10 in the hyperoxic group, but only on day 10 in the control group. Comparison between groups showed a 20% statistically significant increase in wound perfusion in HBO-treated animals compared to control on day 10 (p = 0.05). Laser Doppler imaging was able to detect and quantify the increase in wound bed perfusion resulting from intermittent HBO treatments and shows promise as a noninvasive measure of angiogenesis and wound healing. 相似文献
24.
Ali S. Ziaee Nadia Khatibzadeh Alireza Rahimnia Ahmad S. Mousavi Shaban Mehrvarz 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2005,15(4):270-274
The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old. 相似文献
25.
Omidvari Shapour MD Nezakatgoo Nosrat MD † Ahmadloo Niloofar MD Mohammadianpanah Mohammad MD Mosalaei Ahmad MD 《Dermatologic surgery》2005,31(5):499-501
BACKGROUND: Hemangioma is the most common tumor of infancy. Although it has a basically benign nature and usually spontaneously regresses, a small percentage (5%) have complications that need treatment. Many different therapeutic modalities can be used in this tumor. OBJECTIVE: To investigate the effect of a new method of treatment (intralesional bleomycin injection) in complicated hemangiomas. MATERIALS AND METHODS: In the Department of Radiation Oncology at Nemazee Hospital in Shiraz, Iran, from April 1992 to October 1998, 32 patients with complicated hemangioma were treated with four to six courses of direct injection of bleomycin into the lesion. RESULTS: After a minimum follow-up of 6 years, there was 70 to 100% regression in 18 patients, 50 to 70% in 7 cases, and less than 50% reduction in 7 patients. CONCLUSION: Intralesional injection of bleomycin is an easy, safe, and effective therapeutic modality in complicated cutaneous hemangiomas. 相似文献
26.
27.
M. Ahmad Agil S. Risco M. Mir M. C. Navarro M. A. Ocete J. Jimnez 《Phytotherapy research : PTR》1995,9(2):135-138
The dried (elaterium) or fresh juice from Ecballium elaterium fruit is used in the treatment of various inflammatory conditions in popular medicine. In this study the elaterium is examined for its analgesic and antipyretic effects in several animal models. The elaterium exhibits both analgesic and antipyretic activities. 相似文献
28.
29.
M. Yaqoob R. Ahmad P. McClelland K. A. Shivakumar D. F. Sallomi I. H. Fahal N. B. Roberts T. Helliwell 《Postgraduate medical journal》1993,69(808):124-128
Seventeen severely anaemic and transfusion-dependent haemodialysis patients with a haemoglobin less than 7 g/dl were treated with recombinant human erythropoietin (r-Hu-EPO). Aluminium toxicity was diagnosed by a positive desferrioxamine (DFO) test and bone biopsy. Seven out of eight patients without aluminium toxicity responded to r-Hu-EPO therapy. Similarly all patients with aluminium toxicity (n = 4) but pre-treated with standard dose of DFO prior to r-Hu-EPO therapy responded but none of the patients with untreated aluminium toxicity (n = 5) responded to r-Hu-EPO therapy. In order to achieve adequate response in these patients, r-Hu-EPO and DFO had to be given in combination. The dose of desferrioxamine used to reverse r-Hu-EPO resistance was less and also used for a short time. We therefore confirm r-Hu-EPO resistance owing to aluminium overload and report its successful and safe reversal with low dose DFO therapy. 相似文献
30.
Ahmad Soolari 《Quintessence international, dental digest》2002,33(5):389-396
Periodontal disease is a chronic disease that is perceived by many patients to be nonthreatening. Periodontal therapy has been shown to be less effective if a regular periodontal maintenance schedule is not followed after completion of active therapy. Periodontal maintenance is an integral part of successful periodontal therapy. 相似文献