全文获取类型
收费全文 | 2152篇 |
免费 | 130篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 171篇 |
妇产科学 | 27篇 |
基础医学 | 246篇 |
口腔科学 | 61篇 |
临床医学 | 278篇 |
内科学 | 593篇 |
皮肤病学 | 73篇 |
神经病学 | 65篇 |
特种医学 | 392篇 |
外科学 | 90篇 |
综合类 | 46篇 |
预防医学 | 97篇 |
眼科学 | 19篇 |
药学 | 88篇 |
2篇 | |
肿瘤学 | 108篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 15篇 |
2020年 | 15篇 |
2019年 | 18篇 |
2018年 | 34篇 |
2017年 | 29篇 |
2016年 | 26篇 |
2015年 | 44篇 |
2014年 | 55篇 |
2013年 | 62篇 |
2012年 | 45篇 |
2011年 | 44篇 |
2010年 | 97篇 |
2009年 | 90篇 |
2008年 | 56篇 |
2007年 | 94篇 |
2006年 | 63篇 |
2005年 | 57篇 |
2004年 | 27篇 |
2003年 | 25篇 |
2002年 | 38篇 |
2001年 | 42篇 |
2000年 | 42篇 |
1999年 | 35篇 |
1998年 | 131篇 |
1997年 | 158篇 |
1996年 | 135篇 |
1995年 | 109篇 |
1994年 | 116篇 |
1993年 | 97篇 |
1992年 | 29篇 |
1991年 | 35篇 |
1990年 | 40篇 |
1989年 | 56篇 |
1988年 | 47篇 |
1987年 | 44篇 |
1986年 | 51篇 |
1985年 | 48篇 |
1984年 | 27篇 |
1983年 | 15篇 |
1982年 | 25篇 |
1981年 | 29篇 |
1980年 | 25篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1977年 | 18篇 |
1976年 | 25篇 |
1975年 | 14篇 |
1966年 | 2篇 |
排序方式: 共有2357条查询结果,搜索用时 15 毫秒
991.
992.
Amika S Singh Marijke JM Chin A Paw Stef PJ Kremers Tommy LS Visscher Johannes Brug Willem van Mechelen 《BMC public health》2006,6(1):1-15
Background
Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening.Methods
Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved.Results
Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6–26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than hospitalization of passively detected cases.Conclusion
While the current immigration screening program is unlikely to result in a large change in case rates, domestic follow-up of B-notification patients, including LTBI treatment, is highly cost-effective. If as many as three percent of screened individuals have active TB, and early detection reduces the rate of hospitalization, net savings may be expected. 相似文献993.
Swartz JD; Mandell DM; Faerber EN; Popky GL; Ardito JM; Steinberg SB; Rojer CL 《Radiology》1985,157(2):395-398
Ossification of the membranous labyrinth (labyrinthitis ossificans) develops as the final result of many inflammatory processes, for example, meningitis, blood-borne septic emboli, middle ear infection, and cholesteatoma. Labyrinthine ossification may also occur as a result of previous labyrinthectomy or secondary to trauma. Seven cases of labyrinthine ossification accompanied by severe vertigo and total hearing loss in the affected ear are discussed. The computed tomographic appearance of varying degrees of ossification, the clinical and surgical circumstances from which this disorder may develop, and the various approaches to labyrinthectomy are described. 相似文献
994.
995.
JH Drew K Marriage VV Bayle E Bajraszewski JM McNammara 《Archives of disease in childhood》1976,51(6):454-458
Use of phototherapy for hyperbilirubinaemia in 300 consecutively treated infants has shown that minor complications are common. With a knowledge of these complications and measures taken to minimize their effects, phototherapy appears to be safe in the short term. The long-term follow-up study showed that growth, and in particular head circumference, was not affected. There was, however, a higher incidence of squints and abnormal developmental performance in those infants treated with phototherapy. This may not have been due to phototherapy usage per se. However, because of these findings, it is suggested that phototherapy should not be used indiscriminately for hyperbilirubinaemia until the results of further long-term studies are available. 相似文献
996.
997.
The common acute lymphoblastic leukemia antigen (CALLA) is a 100-kd surface glycoprotein that is present on normal and malignant lymphoid cells. It is a useful marker for distinguishing between clinically important types of acute leukemia. Anti-CALLA monoclonal antibodies (MoAb) also react with mature myeloid cells (granulocytes), where they identify an antigen having a similar molecular weight (mol wt). We now report that the antigens detected by anti-CALLA MoAb on human lymphoid and myeloid cells differ in their behavior and chemistry. Surface- labeling studies indicate that the antigen on lymphoid cells has a mol wt of approximately 100 kd v 110 kd for that on granulocytes. When cells are metabolically labeled with 35S-methionine, differences in the mol wt of these antigens are again observed. Unlike the lymphoid antigen, expression of that on purified granulocytes is not modulated by incubation with specific antibody. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of proteolytic digests of the two antigens fails to clarify their chemical relationship. Thus the antigens detected on these two cell types may share an epitope(s) but be chemically distinct, or CALLA may exist in distinct forms and behave differently on lymphoid cells and granulocytes. 相似文献
998.
999.
CT findings in Swyer-James syndrome 总被引:4,自引:0,他引:4
Swyer-James syndrome (SJS) is usually diagnosed with plain chest radiographs obtained during inspiration/expiration. The authors studied patients with CT to assess its value in the evaluation of this syndrome. In patients with SJS, CT was useful in the determination of bronchial patency (all nine patients), lung parenchymal changes (subpleural infiltrates in six patients, atelectasis in two, and cavities in two), and the extent and degree of bronchiectasis (all nine patients). If CT is used for the evaluation of bronchiectasis, knowledge of the main findings associated with SJS (hyperlucent lung without anteroposterior gradient attenuation [n = 8], small lung [n = 6], and diminished central and peripheral pulmonary arteries [n = 9]) should facilitate the diagnosis of associated SJS. Expiration CT would support the diagnosis with demonstration of air trapping. 相似文献
1000.
Improved control of image optical density with low-dose digital and conventional radiography in bedside imaging 总被引:1,自引:0,他引:1
Schaefer CM; Greene RE; Oestmann JW; Kamalsky JM; Hall DA; Llewellyn HJ; Robertson CL; Rhea JT; Rosenthal H; Rubens JR 《Radiology》1989,173(3):713-716
The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions. 相似文献