全文获取类型
收费全文 | 957篇 |
免费 | 51篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 79篇 |
妇产科学 | 37篇 |
基础医学 | 149篇 |
口腔科学 | 57篇 |
临床医学 | 67篇 |
内科学 | 181篇 |
皮肤病学 | 7篇 |
神经病学 | 38篇 |
特种医学 | 26篇 |
外科学 | 176篇 |
综合类 | 6篇 |
一般理论 | 2篇 |
预防医学 | 55篇 |
眼科学 | 32篇 |
药学 | 14篇 |
肿瘤学 | 70篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 12篇 |
2021年 | 28篇 |
2020年 | 16篇 |
2019年 | 19篇 |
2018年 | 26篇 |
2017年 | 19篇 |
2016年 | 19篇 |
2015年 | 27篇 |
2014年 | 51篇 |
2013年 | 62篇 |
2012年 | 85篇 |
2011年 | 97篇 |
2010年 | 44篇 |
2009年 | 34篇 |
2008年 | 63篇 |
2007年 | 63篇 |
2006年 | 49篇 |
2005年 | 60篇 |
2004年 | 62篇 |
2003年 | 49篇 |
2002年 | 37篇 |
2001年 | 9篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1983年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有1009条查询结果,搜索用时 31 毫秒
51.
Significance of secondary ultrasonographic endometrial thickening in postmenopausal tamoxifen-treated women 总被引:7,自引:0,他引:7
BACKGROUND: Ultrasonography has a limited value in endometrial assessment for identification of endometrial pathologies in postmenopausal tamoxifen-treated patients. METHODS: We compared the rate of endometrial pathologies and the mean +/- SD of endometrial thickness diagnosed after the first and second transvaginal ultrasonographic studies performed on 55 postmenopausal tamoxifen-treated patients with secondary endometrial thickening (Group I). This rate was also compared with 46 similar patients without secondary thickening (Group II). We also compared the mean +/- SD of endometrial thickness detected in various ultrasonographic studies, as well as various clinical features. RESULTS: A significantly higher rate of endometrial pathologies, including two cases of endometrial cancer identified in gynecologically asymptomatic patients (3.6%), was diagnosed in Group I after the second study compared with the first study (52.7% and 9.1%, respectively; P = 0.001) and compared with those diagnosed after the second study in Group II (30.4%; P = 0.03). There was a significant increase (74.7 +/- 115%) in endometrial thickness after the second study compared with the first study performed on Group I (10.7 +/- 5.53 mm and 16.59 +/- 5.53 mm, respectively; P = 0.0001) and a significant difference in endometrial thickness demonstrated in the second study performed on Groups I and II (16.59 +/- 5.53 mm and 11.4 +/- 3.91 mm, respectively; P = 0.001).There were no significant differences in the time elapsed since the diagnosis of breast carcinoma and from the beginning of tamoxifen treatment to the performance of the first ultrasonographic study as well as the time elapsed between the first and second studies performed. CONCLUSIONS: A significant increase (> 50%) in secondary endometrial thickening, measured ultrasonographically, in postmenopausal tamoxifen-treated patients, is associated with a high rate of endometrial pathologies, including endometrial cancer. 相似文献
52.
Dror Tal Liran Domachevsky Ronen Bar Yochai Adir Avi Shupak 《Otology & neurotology》2005,26(6):1204-1207
OBJECTIVE: To present a case series of vestibular symptoms appearing after combined sailing and diving activity, and to discuss the differential diagnosis and the workup algorithm. STUDY DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: Three patients aged 25 to 31 years suffering from unsteadiness and movement sensations after sailing and scuba diving. INTERVENTIONS: Neurotologic evaluation and recompression therapy in a hyperbaric chamber. MAIN OUTCOME MEASURES: The increasing popularity of marine sports and leisure activities has resulted in the exposure of a growing number of people to unique abnormalities not encountered under terrestrial conditions. The otolaryngologist who is involved in the care of these patients is required to diagnose and treat diving-related sinus and ear injuries such as barotrauma and decompression sickness, and also to be familiar with sailing-related disorientation syndromes such as seasickness and mal de debarquement. Treatment modalities for the various abnormalities differ significantly, and early commencement of treatment is often crucial for a successful outcome. CONCLUSION: Whenever doubt exists, recompression treatment must be instituted as soon as possible because of the potential for severe sequelae if the patient is left untreated, and because the risks involved in this therapy are minimal. 相似文献
53.
54.
Paley D Matz AL Kurland DB Lamm BM Herzenberg JE 《Journal of pediatric orthopedics》2005,25(4):539-542
To date, the only way to predict adult height in achondroplastic dwarves has been to consult a growth chart. The purpose of this study was to ascertain whether the multiplier method of predicting adult height at skeletal maturity in healthy persons can be applied to persons with achondroplasia. Previous studies have shown that the multiplier method can be applied to lower limb length, upper limb length, total height, foot length, and foot height. It is therefore reasonable to suggest that the growth pattern for total height in achondroplastic dwarves might also be characterized by a multiplier. Total height multipliers for achondroplastic dwarves ("achondroplasia height multipliers") were calculated from two separate databases by dividing height at maturity by height at each respective age for both genders. Little variability was found among multipliers for each age and among multipliers calculated from different databases. Upper torso (sitting height) multipliers and lower limb multipliers were also derived for achondroplastic dwarves. Lower limb and total height growth rates were slower in achondroplastic dwarves compared with healthy persons. However, sitting height multipliers for achondroplastic dwarves were closely related to sitting height multipliers for healthy persons. Because these findings showed that the multiplier values were independent of population and percentile, the multiplier method may be a valid method for quickly predicting height at any age for achondroplastic dwarves. 相似文献
55.
Schulman CI Cohn SM Blackbourne L Soffer D Hoskins N Bowers N Habib F Crookes B Benjamin B Pizano LR 《The Journal of trauma》2005,59(1):92-95
OBJECTIVE: The purpose of this study was to determine the optimal time interval for identifying a pneumothorax (PTX) on chest radiograph (CXR) after placing a chest tube on water seal. METHODS: One hundred nineteen chest tubes were placed on water seal according to a prospective, observational study protocol. After water seal, both an early (3.1 +/- 2.1 hours) and a late (17.6 +/- 8.0 hours) CXR was obtained. RESULTS: Thirty-one patients had a PTX on follow-up CXRs. There were 22 early and 9 late PTXs identified. Three patients in the early group had a clinically significant PTX or an increase in the size of PTX on follow-up CXR. None of the patients in the late group had a clinically significant PTX (any worsening of their PTX) or required further intervention. CONCLUSION: A normal chest radiograph obtained 3 hours after placing a chest tube on water seal effectively excludes development of a clinically significant pneumothorax. 相似文献
56.
Peritonsillar infiltration of a local anesthetic solution for reduction of posttonsillectomy pain is commonly used although the benefit and complications of this technique have not yet been well established. We report a case of a 4-year-old boy who developed peripheral facial nerve paralysis after perioperative infiltration of bupivacaine and uneventful tonsillectomy. The paralysis was noticed a few minutes after extubation and resolved completely after 8 hours. We assumed this to be caused by the direct action of the local anesthetic agent on the facial nerve. 相似文献
57.
58.
Littner Y Mimouni FB Dollberg S Mandel D 《Archives of pediatrics & adolescent medicine》2005,159(11):1036-1037
OBJECTIVE: To test the hypothesis that articles with negative results are more likely than articles with positive results to be published in journals with lower impact factor. DESIGN AND SETTING: We selected all of the randomized, placebo-controlled trials conducted during the neonatal period between October 1, 1998, and October 1, 2003. Trials were classified as having positive results or negative results (significant or no significant difference, respectively). Only studies dealing with primary outcomes (efficacy) were included. MAIN OUTCOME MEASURES: The impact factor of each journal was determined, and the sample size for each study was noted. RESULTS: There were 233 articles that fulfilled the inclusion criteria. There was a significant difference between the 2 groups in terms of impact factor (P = .03) but not sample size (P = .30). Impact factor correlated with both sample size and the type of study results (positive results vs negative results; P<.05). CONCLUSION: Articles with negative results are more likely than articles with positive results to be published in journals with lower impact factor. 相似文献
59.
Secondary ultrasound examination increases the sensitivity of the FAST exam in blunt trauma 总被引:3,自引:0,他引:3
Blackbourne LH Soffer D McKenney M Amortegui J Schulman CI Crookes B Habib F Benjamin R Lopez PP Namias N Lynn M Cohn SM 《The Journal of trauma》2004,57(5):934-938
INTRODUCTION: Approximately one third of stable patients with significant intra-abdominal injury do not have significant intraperitoneal blood evident on admission. We hypothesized that a delayed, repeat ultrasound study (Secondary Ultrasound--SUS) will reveal additional intra-abdominal injuries and hemoperitoneum. METHODS: We performed a prospective observational study of trauma patients at our Level I trauma center from April 2003 to December 2003. Patients underwent an initial ultrasound (US), followed by a SUS examination within 24 hours of admission. Patients not eligible for a SUS because of early discharge, operative intervention or death were excluded. All US and SUS exams were performed and evaluated by surgical/emergency medicine house staff or surgical attendings. RESULTS: Five hundred forty-seven patients had both an initial US and a SUS examination. The sensitivity of the initial US in this patient population was 31.1% and increased to 72.1% on SUS (p < 0.001) for intra-abdominal injury or intra-abdominal fluid. The specificity for the initial US was 99.8% and 99.8% for SUS. The negative predictive value was 92.0% for the initial US and increased to 96.6% for SUS (p = 0.002). The accuracy of the initial ultrasound was 92.1% and increased to 96.7% on the SUS (p < 0.002). No patient with a negative SUS after 4 hours developed clinically significant hemoperitoneum. CONCLUSION: A secondary ultrasound of the abdomen significantly increases the sensitivity of ultrasound to detect intra-abdominal injury. 相似文献
60.
Stern F Berner YN Polyak Z Komarnitsky M Sela BA Hopp M Dror Y 《Clinical biochemistry》2004,37(11):1002-1009
OBJECTIVES: To show the effect of homocysteine (Hcy) on the degradation rates of proteins. DESIGN AND METHODS: Degradation rates of short-lived proteins in neutrophils were measured in in vivo human model of elevated plasma Hcy and lower vitamin status and in animal model of Hcy added in vitro to rat neutrophils. RESULTS: In the human study, we found significant coefficients of correlation between plasma total homocysteine (tHcy) and the degradation rates of 21 protein fractions. In the animal model, Hcy significantly increased degradation rates of 57 protein fractions. CONCLUSIONS: The increase in protein degradation rates, induced by Hcy, may provide a clue to our understanding of the mechanism of Hcy detrimental effects. Hcy may amplify the specific effect of cellular solutes on protein conformation, thereby monitor protein degradation rates to control enzyme activity. Consequently, the cell may lose its ability to maintain an efficient control of some crucial metabolic pathways, possibly leading to atherogenesis. 相似文献