全文获取类型
收费全文 | 2266篇 |
免费 | 234篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 44篇 |
妇产科学 | 32篇 |
基础医学 | 255篇 |
口腔科学 | 40篇 |
临床医学 | 275篇 |
内科学 | 408篇 |
皮肤病学 | 32篇 |
神经病学 | 73篇 |
特种医学 | 185篇 |
外科学 | 231篇 |
综合类 | 280篇 |
现状与发展 | 1篇 |
一般理论 | 3篇 |
预防医学 | 195篇 |
眼科学 | 27篇 |
药学 | 140篇 |
中国医学 | 53篇 |
肿瘤学 | 287篇 |
出版年
2023年 | 19篇 |
2022年 | 39篇 |
2021年 | 71篇 |
2020年 | 48篇 |
2019年 | 59篇 |
2018年 | 66篇 |
2017年 | 47篇 |
2016年 | 55篇 |
2015年 | 50篇 |
2014年 | 75篇 |
2013年 | 92篇 |
2012年 | 107篇 |
2011年 | 121篇 |
2010年 | 81篇 |
2009年 | 71篇 |
2008年 | 86篇 |
2007年 | 94篇 |
2006年 | 117篇 |
2005年 | 92篇 |
2004年 | 148篇 |
2003年 | 186篇 |
2002年 | 164篇 |
2001年 | 127篇 |
2000年 | 77篇 |
1999年 | 50篇 |
1998年 | 54篇 |
1997年 | 41篇 |
1996年 | 28篇 |
1995年 | 27篇 |
1994年 | 26篇 |
1993年 | 23篇 |
1992年 | 17篇 |
1991年 | 18篇 |
1990年 | 13篇 |
1989年 | 25篇 |
1988年 | 13篇 |
1987年 | 10篇 |
1986年 | 14篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 10篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1978年 | 10篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1973年 | 7篇 |
1968年 | 4篇 |
排序方式: 共有2571条查询结果,搜索用时 0 毫秒
131.
132.
This study prospectively assessed the 4 to 8 yr outcome of apical surgery performed by graduate students in phases I and II of the Toronto Study. The study cohort included 155 teeth in 138 patients. Outcome was assessed by a blinded and calibrated examiner. Clinical and radiographic measures were used for a dichotomous outcome: healed (no signs and symptoms, Periapical Index score = 2 or scar), or diseased (presence of signs and symptoms, or Periapical Index score >/= 3). The recall rate was 85% and the overall healed rate 74%. Healed rate was significantly higher for teeth with small (= 5 mm) than larger preoperative lesions (chi, p = 0.02). Logistic Regression revealed an increased odds of disease persistence for teeth with larger preoperative lesions (OR = 3.81, CI = 1.2-12.1), and preoperative root-filling of adequate length (OR = 3.7, CI = 1.1-11.1). Preoperative lesion size and root-filling length were significant predictors of outcome of apical surgery. 相似文献
133.
PURPOSE: The purpose of this study was to report on the results of submuscular ulnar nerve transposition (SMUNT) for treatment of cubital tunnel syndrome in a young, active duty, military population. METHODS: Twenty patients (20 extremities) were evaluated retrospectively a minimum of 12 months after surgery. Outcome analyses were performed using the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and the Bishop-Kleinman rating scales, physical examination, return-to-work analysis, evaluation of complication rate, and overall patient satisfaction. RESULTS: At an average follow-up evaluation of 24 months (range, 12-38 mo), 19 patients had returned to full military active duty work status. The average duration of limited work capacity after surgery was 4.8 months (range, 3-7 mo). The DASH scores improved from an average of 32.5 points before surgery to 6.2 points after surgery. In 19 patients the functional outcome evaluated with the Bishop-Kleinman rating system was excellent. There were no poor outcomes using this rating score. Statistically significant improvements in both key pinch and grip strength were noted. Complications included one permanent and 2 transient neuropraxias of the medial antebrachial cutaneous nerve. Overall 19 of 20 patients were satisfied with the procedure and would have the surgery again if required. CONCLUSIONS: Submuscular ulnar nerve transposition for cubital tunnel syndrome provides a reliable rate of return to full active duty work in military personnel with good patient satisfaction and minimal complications. 相似文献
134.
Surgical treatment of congenital syndactyly of the hand 总被引:1,自引:0,他引:1
Dao KD Shin AY Billings A Oberg KC Wood VE 《The Journal of the American Academy of Orthopaedic Surgeons》2004,12(1):39-48
Syndactyly is a congenital anomaly of the hand that is more common in males, is present bilaterally in 50% of affected patients, and often is associated with other musculoskeletal malformations or systemic syndromes. The goal of syndactyly release is to create a functional hand with the fewest surgical procedures while minimizing complications. For simple syndactyly, surgical reconstruction can begin at approximately 6 months, although many surgeons prefer to wait until the infant is 18 months old. Special situations, such as complex syndactyly and involvement of border digits, may warrant surgical intervention earlier than 6 months. Reconstruction of the web commissure is the most technically challenging part of the operation, followed by separation of the remaining digits. Full-thickness skin grafting is almost always required for soft-tissue coverage. Complex syndactyly and syndactyly associated with other hand anomalies warrant special consideration. After reconstruction, patients should be examined periodically until they have achieved skeletal maturity because late complications such as web creep can occur. 相似文献
135.
136.
Wu C Ray RM Lin MG Gao DL Horner NK Nelson ZC Lampe JW Hu YW Shannon J Stalsberg H Li W Fitzgibbons D Porter P Patterson RE Satia JA Thomas DB 《American journal of epidemiology》2004,160(10):945-960
This study was conducted to identify reproductive and dietary factors associated with benign proliferative mammary epithelial cell changes. Subjects were women enrolled in a randomized trial of breast self-examination in Shanghai, China. Women who developed fibrocystic breast conditions classified as nonproliferative (175 women), proliferative (181 women), or proliferative with atypia (33 women) between 1995 and 2000 and 1,070 unaffected trial participants were administered general risk factor and food frequency questionnaires. Conditional logistic regression was used to estimate adjusted odds ratios and 95% confidence intervals. High parity and consumption of fresh fruits and vegetables were more strongly associated with a reduced risk of proliferative and atypical lesions than with nonproliferative conditions. For the fourth quartile of consumption versus the first, odds ratios for lesions diagnosed as nonproliferative, proliferative, and proliferative with atypia were 0.4 (95% confidence interval (CI): 0.2, 0.7), 0.2 (95% CI: 0.1, 0.4), and 0.1 (95% CI: 0.03, 0.5), respectively, for fruit intake and 0.6 (95% CI: 0.3, 1.1), 0.4 (95% CI: 0.2, 0.7), and 0.1 (95% CI: 0.1, 0.9), respectively, for vegetable intake. Reduced but nonsignificant risks in relation to soy products were observed for proliferative and atypical lesions. No single nutrient or botanical family was appreciably more strongly associated with proliferative conditions than with nonproliferative conditions, after results were controlled for total fruit and vegetable consumption. A diet rich in fruits and vegetables may reduce cellular proliferation in the mammary epithelium; this is one mechanism by which such a diet could reduce risk of breast cancer. 相似文献
137.
Synthesis and PGE<Subscript>2</Subscript> inhibitory activity of vinylated and allylated chrysin analogues 总被引:3,自引:0,他引:3
Vinylated and allylated chrysin analogues were prepared as congeners of prenylated flavonoids and evaluated their anti-inflammatory activity. 8-Substituted chrysin analogues were prepared from 2'-hydroxy-3'-iodo-4',6'-dimethoxyacetophenone in 3 steps. 3-Allylated chrysin analogues were prepared from chrysin in 3 steps. Synthesized chrysin analogues (4, 5 and 8) showed moderate inhibitory activities of PGE2 production from LPS-induced RAW 264.7 cells. 相似文献
138.
139.
Comparative evaluation of super high-resolution CT scan and virtual bronchoscopy for the detection of tracheobronchial malignancies 总被引:4,自引:0,他引:4
OBJECTIVES: Novel imaging modalities are currently available for the noninvasive evaluation of the tracheobronchial tree. This study was undertaken to compare the diagnostic potentials of conventional CT scanning, super high-resolution CT (SHR-CT) scanning, and virtual bronchoscopy (VB) directly with fiberoptic bronchoscopy (FB) for the detection of tracheobronchial neoplasms. DESIGN: Prospective observer study, in which 44 consecutive patients with thoracic malignancies were evaluated using several diagnostic imaging modalities. Images of the thorax were interpreted by individuals blind to the results of FB for the detection of endoluminal, obstructive, or mucosal lesions. MEASUREMENTS AND RESULTS: Image acquisition and simulation of the tracheobronchial anatomy were created successfully in all patients. Thirty-two patients who underwent both SHR-CT scanning and VB had correlative FBs within 1 month. In all nine patients who had a normal anatomy, SHR-CT scanning and VB accurately correlated with the FB findings. However, CT scanning demonstrated two false-positive obstructive lesions in one patient. Twenty-three patients had a total of 35 abnormal FB findings. The sensitivities of SHR-CT scanning and VB for the detection of endoluminal, obstructive, and mucosal lesions were 90%, 100%, and 16%, respectively. The overall sensitivities and specificities of SHR-CT scanning and VB were 83% and 100%, respectively. In contrast, CT scanning had sensitivities of 50%, 72%, and 0% for the detection of endoluminal, obstructive, and mucosal lesions with an overall sensitivity and specificity of 59%, and 85%, respectively. There was no case in which conventional CT scanning was better at detecting lesions than either SHR-CT scanning or VB. CONCLUSIONS: SHR-CT scanning and VB are accurate, noninvasive methods for identifying obstructions and endoluminal lesions within the respiratory tract. Thus, these novel imaging techniques are valuable as complementary modalities to FB, providing information that is useful for the detection and management of airway malignancies. 相似文献
140.
Wong BJ Chao KK Kim HK Chu EA Dao X Gaon M Sun CH Nelson JS 《American journal of rhinology》2001,15(2):109-116
Interest in reconstruction and modification of the facial cartilaginous frameworks using advanced technology and instrumentation is growing rapidly. Despite this maturing interest, no animal model has been established to provide morphologic cartilage tissue with similar characteristics to human septum in suitable quantities. The objective of this study was to characterize porcine and lagomorph (rabbit) nasal septal cartilage tissue. Both models share great similarity with their human counterpart and provide a low-cost, high-volume, and easily obtained source of bulk cartilage tissue. We present a technique for harvesting intact septal cartilages from these species, and characterize select cellular, metabolic, and physical properties using pulse-chase radiolabeling, flow cytometry, and mechanical analysis. Our selective evaluation of key tissue properties establishes these species as appropriate animal models for nasal septal cartilaginous surgery. 相似文献