全文获取类型
收费全文 | 3173篇 |
免费 | 467篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 73篇 |
妇产科学 | 306篇 |
基础医学 | 214篇 |
口腔科学 | 52篇 |
临床医学 | 990篇 |
内科学 | 454篇 |
皮肤病学 | 57篇 |
神经病学 | 66篇 |
特种医学 | 303篇 |
外科学 | 325篇 |
综合类 | 128篇 |
一般理论 | 1篇 |
预防医学 | 369篇 |
眼科学 | 36篇 |
药学 | 115篇 |
肿瘤学 | 156篇 |
出版年
2023年 | 49篇 |
2021年 | 24篇 |
2020年 | 52篇 |
2019年 | 42篇 |
2018年 | 79篇 |
2017年 | 115篇 |
2016年 | 106篇 |
2015年 | 120篇 |
2014年 | 139篇 |
2013年 | 143篇 |
2012年 | 97篇 |
2011年 | 140篇 |
2010年 | 140篇 |
2009年 | 136篇 |
2008年 | 95篇 |
2007年 | 97篇 |
2006年 | 94篇 |
2005年 | 80篇 |
2004年 | 80篇 |
2003年 | 80篇 |
2002年 | 83篇 |
2001年 | 81篇 |
2000年 | 51篇 |
1999年 | 89篇 |
1998年 | 114篇 |
1997年 | 122篇 |
1996年 | 118篇 |
1995年 | 110篇 |
1994年 | 73篇 |
1993年 | 58篇 |
1992年 | 51篇 |
1991年 | 56篇 |
1990年 | 32篇 |
1989年 | 62篇 |
1988年 | 56篇 |
1987年 | 51篇 |
1986年 | 55篇 |
1985年 | 70篇 |
1984年 | 49篇 |
1983年 | 39篇 |
1982年 | 43篇 |
1981年 | 25篇 |
1980年 | 22篇 |
1979年 | 20篇 |
1978年 | 36篇 |
1977年 | 27篇 |
1976年 | 24篇 |
1975年 | 23篇 |
1974年 | 13篇 |
1970年 | 13篇 |
排序方式: 共有3649条查询结果,搜索用时 421 毫秒
1.
2.
M. Parikh M.D. J. Duncombe M.B. B.S. G.A. Fielding M.D. 《Surgery for obesity and related diseases》2006,2(5):99-522
BACKGROUND: Many mild-to-moderately obese individuals (body mass index [BMI] 30-35 kg/m(2)) have serious diseases related to their obesity. Nonoperative therapy is ineffective in the long term, yet surgery has never been made widely available to this population. METHODS: Between 1996 and 2004, 93 patients with a BMI of 30-35 kg/m(2) underwent laparoscopic adjustable gastric banding with the LAP-BAND. All patients were referred by their primary physician, entered into a comprehensive bariatric surgery program at one Australian center, and operated on by one surgeon. Data on all patients were collected prospectively and entered into an electronic registry. The study parameters included preoperative age, gender, BMI, presence of co-morbidities, percentage of excess weight loss, and resolution of co-morbidities. RESULTS: The mean age was 44.6 years (range 16-76), mean weight was 98 kg, and the mean BMI was 32.7 kg/m(2) (range 30-34). Of the 93 patients, 42 (45%) had co-morbidities, including asthma, diabetes, hypertension, and sleep apnea. The proportion of patients in follow-up was 79%, 85%, and 89% at 1, 2, and 3 years, respectively. The mean weight was reduced to 71 kg at 1 year, 72 kg at 2 years, and 72 kg at 3 years. The mean BMI was reduced to 27.2 +/- 2.2, 27.3 +/- 3.1, and 27.6 +/- 3.7 kg/m(2), respectively, and the mean percentage of excess weight loss was 57.9% +/- 24.5%, 57.6 +/- 29.3%, and 53.8% +/- 32.8% at 1, 2, and 3 years, respectively. At 3 years, the BMI was 18-24 kg/m(2) in 34%, 25-29 kg/m(2) in 51%, and 30-35 kg/m(2) in 10%. At 3 years, the percentage of excess weight loss was <25% in 10%, 25-50% in 24%, 50-75% in 51%, and >75% in 10%. The co-morbidities improved or completely resolved in most patients. No mortality occurred. CONCLUSION: We are very encouraged by this series of low BMI patients treated with the LAP-BAND. Their weight loss has been good, the complications have been minimal, and the co-morbidities have partially or wholly resolved. With additional study, it is reasonable to expect the weight guidelines for bariatric surgery to be altered to include patients with a BMI of 30-35 kg/m(2). 相似文献
3.
D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
4.
Sonographic features of benign thyroid nodules: interobserver reliability and overlap with malignancy. 总被引:4,自引:0,他引:4
Jeffrey R Wienke Wui K Chong Julia R Fielding Kelly H Zou Carol A Mittelstaedt 《Journal of ultrasound in medicine》2003,22(10):1027-1031
OBJECTIVE: To prospectively determine the sonographic findings of nodular hyperplasia of the thyroid, to compare these with reported findings associated with malignancy, and to assess interobserver reliability. METHODS: Seventy thyroid nodules were scanned, and then biopsies of the nodules were performed under sonographic guidance with fine-needle cytologic analysis; in all cases images were reviewed by 2 experienced radiologists without knowledge of clinical outcome. Findings reported associated with malignancy were specifically assessed. Interobserver agreement between the expert and secondary readers for each finding was calculated by the kappa or weighted kappa statistic and the Fisher exact test of independence. RESULTS: There were 68 benign and 2 malignant nodules in a population of 63 female and 7 male patients. The mean benign nodule size was 2.9 cm; 60% were solid; 54% were hypoechoic; 59% were microlobulated or macrolobulated; 47% had central vascularity; 24% contained calcifications; and 82% were elliptical in shape. There was very good interobserver reliability for the presence of calcium (kappa = 0.91) and good agreement for the presence and location of vascularity (kappa = 0.75) and the amount of cystic components (kappa = 0.62; all P < .01). CONCLUSIONS: Sixty-nine percent of benign nodules had at least 1 finding reported previously as associated with malignancy. The interobserver reliability of the sonographic findings was good to very good for 3 of the 5 findings assessed. 相似文献
5.
6.
George A. Fielding 《Journal of hepato-biliary-pancreatic sciences》2002,9(6):723-728
The modern surgeon's approach to choledocholithiasis depends his or her view of cholangiography. During the early 1990 there was a swing away from cholangiography, which had previously been common practice. This was because of perceptions of difficulty with the technique, the time it took, and perhaps an implied increase in costs because of the time factor. There was no evidence on which to base this decision. This led to a marked upswing in the use of endoscopic retrograde cholangiopancreatography (ERCP). There were a large number of ERCPs with normal results performed prior to laparoscopic cholecystectomy. This paper states the case for intraoperative cholangiography and common bile duct clearance at the time of cholecystectomy. It is hoped that this technique will be adopted so patients can undergo a single procedure to remove their gallstones and common bile duct stones if they exist and to decrease the incidence of normal preoperative ERCPs and the need for a second procedure postoperatively to clear stones if they are found. 相似文献
7.
V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
8.
9.
10.
Patients with the irritable bowel syndrome have significantly more rapid and significantly greater slowing of the pulse rate than do age-, sex-, and stressor-matched controls when their pulse rate is measured at initial outpatient clinic attendance. These findings provide further evidence that altered autonomic function exists in patients with the irritable bowel syndrome. 相似文献