全文获取类型
收费全文 | 2015813篇 |
免费 | 164991篇 |
国内免费 | 8022篇 |
专业分类
耳鼻咽喉 | 27379篇 |
儿科学 | 62642篇 |
妇产科学 | 56577篇 |
基础医学 | 281116篇 |
口腔科学 | 57143篇 |
临床医学 | 180517篇 |
内科学 | 402866篇 |
皮肤病学 | 45501篇 |
神经病学 | 165100篇 |
特种医学 | 82155篇 |
外国民族医学 | 433篇 |
外科学 | 315317篇 |
综合类 | 52292篇 |
现状与发展 | 4篇 |
一般理论 | 653篇 |
预防医学 | 161063篇 |
眼科学 | 45304篇 |
药学 | 144492篇 |
6篇 | |
中国医学 | 3833篇 |
肿瘤学 | 104433篇 |
出版年
2018年 | 19412篇 |
2016年 | 18108篇 |
2015年 | 20691篇 |
2014年 | 29056篇 |
2013年 | 43575篇 |
2012年 | 55075篇 |
2011年 | 58716篇 |
2010年 | 36004篇 |
2009年 | 34733篇 |
2008年 | 55022篇 |
2007年 | 59177篇 |
2006年 | 60074篇 |
2005年 | 58380篇 |
2004年 | 56176篇 |
2003年 | 54482篇 |
2002年 | 51920篇 |
2001年 | 91041篇 |
2000年 | 93451篇 |
1999年 | 78477篇 |
1998年 | 24038篇 |
1997年 | 21667篇 |
1996年 | 22343篇 |
1995年 | 22033篇 |
1994年 | 20745篇 |
1993年 | 19515篇 |
1992年 | 65805篇 |
1991年 | 64285篇 |
1990年 | 62195篇 |
1989年 | 59419篇 |
1988年 | 55460篇 |
1987年 | 54620篇 |
1986年 | 51582篇 |
1985年 | 49982篇 |
1984年 | 38415篇 |
1983年 | 32541篇 |
1982年 | 20577篇 |
1981年 | 18724篇 |
1980年 | 17627篇 |
1979年 | 36367篇 |
1978年 | 26349篇 |
1977年 | 22237篇 |
1976年 | 20417篇 |
1975年 | 21732篇 |
1974年 | 26152篇 |
1973年 | 25042篇 |
1972年 | 23520篇 |
1971年 | 21649篇 |
1970年 | 20225篇 |
1969年 | 19286篇 |
1968年 | 17702篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
D P Taggart D C McMillan T Preston R Richardson A Shenkin H J Burns D J Wheatley 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):271-274
Total energy expenditure (TEE) was measured by doubly labeled water in 13 preoperative patients undergoing elective coronary artery surgery and compared to resting energy expenditure (REE) measured by indirect calorimetry (IC) calculated from the Harris-Benedict (HB) formula or from formulas based on midarm circumference and arm muscle circumference. Mean REE measured by IC and calculated from the HB, midarm circumference, arm muscle circumference formulas were 62, 75, 62, and 69%, respectively, of TEE measured by doubly labeled water. REE measured by IC correlated significantly with that predicted by the HB (p = 0.006) but not the anthropometric formulas. The relationship between REE derived from anthropometric predictive formulas and REE measured by IC is altered in ischemic heart disease. 相似文献
993.
Nonsyndromal autosomal recessive profound childhood deafness will affect about one in 4000 children in western Europe. A nonsyndromal autosomal recessive type of profound childhood deafness was thought to be the cause of deafness in at least eight and probably 12 children from a large family with various consanguineous matings and other family interrelations. Audiograms of all affected deaf children showed a profound childhood deafness with only a very slight variation. Audiometric examinations, such as pure-tone audiometry, high-frequency audiometry, stapedial reflexes, and Bekesy audiometry, of ten obligate or presumed carriers did not show any significant findings that would allow identification of carriers of this autosomal recessive gene. Families like this one seem to be very rare. Large clinically well-studied families like this one are indispensable for gene linkage studies of nonsyndromal autosomal recessive types of profound childhood deafness. Such studies should make it possible to trace the origin of these types of childhood deafness at an early age. In consequence, carrier detection should also become available. 相似文献
994.
After ingesting or inhaling laundry detergent powder, eight children required hospital admission. The predominant symptoms were stridor, drooling, and respiratory distress. All but one patient underwent endoscopy of the airways and the esophagus, five children were admitted to the intensive care unit, and four children required endotracheal intubation. Laundry detergent ingestions are generally considered to have minor consequences, and there exists a paucity of literature on the subject. Evidence of significant morbidity incurred because of ingestion or inhalation of sodium carbonate-containing laundry detergent powder is presented, together with a review of the existing literature. 相似文献
995.
996.
997.
B J Braakhuis D A Laarman J J Nauta M van Walsum G A van Dongen G B Snow 《Archives of otolaryngology--head & neck surgery》1989,115(9):1076-1078
Tumor material from 91 patients with squamous cell carcinoma of the head and neck was transplanted subcutaneously in athymic nude mice. In the first (man to mouse) passage, the calculated mean probability of tumor take in a single mouse was 11%. The probability of growth in the first passage was significantly better for moderately and poorly differentiated tumors than for well-differentiated tumors. Also, the implantation of lymph node material resulted in a significantly better tumor take rate than material taken from a primary tumor. Transplantability was not dependent on the following characteristics: localization, T or N stage of the tumor, or the sex of the patients. Once growth was established, all variables studied had no influence on the probability of growth in the subsequent mouse passages. A relationship between tumor growth in nude mice and patient prognosis could not be found. When transplanting head and neck squamous cell carcinoma in nude mice, it has to be recognized that some tumor characteristics will influence the success of tumor growth. 相似文献
998.
Usher syndrome: clinical findings and gene localization studies 总被引:3,自引:0,他引:3
William J. Kimberling Sandra L. H. Davenport Ira Priluck Valorie White Karen Biscone-Halterman Patrick E. Brookhouser Claes G. Mller Gunnar Lund Timothy J. Grissom Michael D. Weston 《The Laryngoscope》1989,99(1):66-72
The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized. 相似文献
999.
Percutaneous transluminal coronary angioplasty has grown exponentially since its introduction. Currently, selection criteria include single-vessel and multivessel disease, stable and unstable angina, and acute infarction. The outcome depends on specific patient and angiographic characteristics. In ideal lesions, success rates should be greater than 90%, with low morbidity and mortality. With more severe and diffuse multivessel disease, success rates are lower and complication rates are higher. In these cases, percutaneous transluminal coronary angioplasty still offers a reasonable option, provided complete revascularization can be achieved or the angina-producing lesion dilated. Numerous issues remain unresolved, including (1) the role of percutaneous transluminal coronary angioplasty vs coronary surgery (currently being tested), (2) restenosis, which occurs in approximately 30% of treated lesions, and (3) organizational adjustments such as training and certification to maintain high standards of care. 相似文献
1000.
Gram negative endotoxins play a contributory role in the syndrome which results from over consumption of carbohydrates by horses and ponies. Since the antibiotic polymyxin B exerts a direct anti-endotoxin effect by chemically modifying the active lipid A moiety of endotoxin, it might be expected to protect horses after carbohydrate overload and provide a new therapeutic and experimental tool for this condition. The present study was undertaken to evaluate the effect of polymyxin B on hemostatic, hemodynamic, acid-base, and clinical aspects of the syndrome resulting from carbohydrate overload. Experimentally-induced carbohydrate overload resulted in lactic acidosis, hypercoagulability, hypovolemic shock and lameness. Although there was a slight delay in the onset of clinical signs resulting from experimental carbohydrate overload in treated animals, polymyxin B administered iv at 2.5 mg/kg every 6 hr failed to significantly ameliorate the coagulopathy, acidosis, lameness and shock induced by alimentary carbohydrate overload. 相似文献