全文获取类型
收费全文 | 458篇 |
免费 | 17篇 |
国内免费 | 2篇 |
专业分类
儿科学 | 23篇 |
妇产科学 | 21篇 |
基础医学 | 51篇 |
口腔科学 | 6篇 |
临床医学 | 48篇 |
内科学 | 52篇 |
皮肤病学 | 11篇 |
神经病学 | 29篇 |
特种医学 | 12篇 |
外科学 | 46篇 |
综合类 | 103篇 |
预防医学 | 28篇 |
眼科学 | 7篇 |
药学 | 20篇 |
中国医学 | 1篇 |
肿瘤学 | 19篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 7篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 15篇 |
2012年 | 31篇 |
2011年 | 18篇 |
2010年 | 29篇 |
2009年 | 28篇 |
2008年 | 33篇 |
2007年 | 28篇 |
2006年 | 27篇 |
2005年 | 13篇 |
2004年 | 24篇 |
2003年 | 16篇 |
2002年 | 17篇 |
2001年 | 7篇 |
2000年 | 21篇 |
1999年 | 16篇 |
1998年 | 14篇 |
1997年 | 14篇 |
1996年 | 11篇 |
1995年 | 4篇 |
1994年 | 10篇 |
1993年 | 2篇 |
1992年 | 9篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1948年 | 1篇 |
1936年 | 1篇 |
1909年 | 1篇 |
排序方式: 共有477条查询结果,搜索用时 15 毫秒
101.
Background
Rare failures in amelogenin-based gender typing of individuals have been observed globally. In this study, we report the deletion of a large fragment of the amelogenin gene in 10 individuals out of 4,257 male samples analyzed from 104 different endogamous populations of India. 相似文献102.
103.
Diversity and plasticity of self recognition during the development of multiple sclerosis. 总被引:9,自引:4,他引:5 下载免费PDF全文
V K Tuohy M Yu B Weinstock-Guttman R P Kinkel 《The Journal of clinical investigation》1997,99(7):1682-1690
Recent studies using murine animal model systems indicate that clinical progression of autoimmune disease may be due to the sequential accumulation of neoautoreactivity characterized by extensive plasticity of self recognition. In the present study, we addressed the question of whether a similar paradigm of self recognition is implicated in the development of multiple sclerosis (MS), a demyelinating disease with a presumed autoimmune etiology. Our approach was to determine serial changes over a 12-18-mo period in response to an epitope-mapping series of 265 12-mer peptides of myelin proteolipid protein (PLP) by patients with isolated monosymptomatic demyelinating syndromes (IMDS), a group of distinct clinical disorders with variable rates of progression to MS. Our data showed that an extensive array of proteolipid protein peptides could elicit autoreactivity. Moreover, differential autoreactive patterns were evident within IMDS patient subpopulations. Monocentric monophasic IMDS patients with no evidence of prior subclinical disease typically showed fully sustained autoreactivity characterized by extensive plasticity, epitope focusing, shifting, and spreading of responses to new self determinants. In contrast, multicentric monophasic IMDS patients with putative evidence of prior asymptomatic lesion formation typically showed partially sustained autoreactivity characterized by abrupt abrogation of responses to an extensive array of self determinants. No sustained autoreactivity was observed in normal control subjects or in patients with other neurologic diseases. Our results indicate that self recognition associated with the development of MS is a developmental process characterized by autoreactive diversity, plasticity, and instability. 相似文献
104.
Corrosive strictures of the esophagus are difficult to treat, however, prompt and appropriate management of corrosive burns
to the esophagus can prevent the formation of strictures. In a developing country like India, where facilities for early treatment
are not easily available, strictures are an ineviatable consequence. If the strictures are extensive, dilatational therapy
proves ineffective and offers no substantial benefit to the patients. Twenty patients with extensive corrosive strictures
of the esophagus were surgically managed; by esophageal bypass in 13 and esophagectomy in 7. Surgical treatment restored normal
swallowing in all the patients. The common post-operative complications to occur were: pulmonary complications, anastomotic
leak and stricture, gastric outlet obstruction and reflux esophagitis. For extensive corrosive strictures of the esophagus,
we advocate early surgical treatment rather than prolonged dilatational therapy. 相似文献
105.
E. L. Tuohy 《American journal of public health》1909,19(2):224-226
106.
107.
108.
The autoimmune T cell repertoire in experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis (MS) is characterized by CD4(+)T cells of the Th1 phenotype that recognize peptide determinants of central nervous system (CNS) myelin proteins in an MHC class II-restricted manner. Our recent studies and those performed by others have shown that progression to chronicity in EAE and MS is accompanied by a broadening of the T cell repertoire with time. This acquired neo-autoreactivity is commonly referred to as epitope spreading and is presumably the result of endogenous priming to new self-determinants during the CNS inflammation that accompanies disease onset and relapse. In the present study we extend our earlier observations by showing that disease progression in both EAE and MS is accompanied by two concurrent events, viz. (1) the spontaneous regression of the primary established autoimmune repertoire associated with disease onset, and (2) the emergence of the epitope spreading cascade associated with disease progression. Our data show that disease initiation and disease progression in both EAE and MS are typically associated with distinctly different autoimmune T cell repertoires. Our data support the view that the natural development of self-recognition during autoimmune disease may best be understood when considered in the temporal context of an 'epitope du jour' and 'moving target' perspective. 相似文献
109.
OBJECTIVE: To assess the predictive ability of a universal predischarge serum bilirubin measurement to screen for risk of subsequent significant hyperbilirubinemia in the direct Coombs negative healthy term and near-term newborn during the first postnatal week. METHODS: Total serum bilirubin (TSB) levels were obtained at the time of the routine metabolic screen in all term and near-term newborns cared for in the Pennsylvania Hospital Well Baby Nursery (n = 13 003). Postnatal age (in hours) at the time of TSB measurement was recorded. A percentile-based bilirubin nomogram for the first week was constructed from hour-specific predischarge and postdischarge TSB values of newborns (n = 2840; median BW = 3230 g and median gestational age = 39 weeks) who met classification criteria for healthy newborns (excluding those with a positive direct Coombs test or those requiring phototherapy before age 60 hours) and who were enrolled in a hospital supervised home or outpatient follow-up program. The accuracy of the predischarge TSB as a predictor of subsequent degree of hyperbilirubinemia was determined. RESULTS: The study patients in the nomogram were racially diverse. Nearly 60% were breastfed. Predischarge, 6.1% of the study population (172/2840) had TSB values in the high-risk zone (>/=95th percentile) at 18 to 72 hours; of these, 39.5% (68/172) remained in that zone (likelihood ratio [LR] = 14.08, sensitivity = 54%; specificity = 96.2%, probability = 39.5%). Predischarge, 32.1% of the population (912/2840) had TSB values in the intermediate-risk zone. In a clinically significant minority of these newborns (58/912 or 6.4%), the postdischarge TSB moved into the high-risk zone (LR of this move: 3.2 from the upper-intermediate zone and.48 from the lower-intermediate risk zone). The predischarge TSB in 61.8% of the newborns (1756/2840) was in the low-risk zone (<40th percentile) and there was no measurable risk for significant hyperbilirubinemia (LR = 0, sensitivity = 100%; specificity = 64.7%; probability = 0%). CONCLUSIONS: An hour-specific TSB before hospital discharge can predict which newborn is at high, intermediate or low risk for developing clinically significant hyperbilirubinemia (specifically defined as TSB levels >/=95th percentile for age in hours). Risk designation and subsequent increases or decreases of in TSB can be easily monitored on an hour-specific percentile based predictive bilirubin nomogram. A predischarge TSB measured as a universal policy would facilitate targeted intervention and follow-up in a safe, cost-effective manner. In conjunction with bilirubin practice parameter of the American Academy of Pediatrics, it could reduce the potential risk for bilirubin-induced neurologic dysfunction. 相似文献
110.