全文获取类型
收费全文 | 348篇 |
免费 | 22篇 |
国内免费 | 31篇 |
专业分类
儿科学 | 34篇 |
妇产科学 | 2篇 |
基础医学 | 21篇 |
口腔科学 | 13篇 |
临床医学 | 61篇 |
内科学 | 64篇 |
皮肤病学 | 1篇 |
神经病学 | 21篇 |
特种医学 | 58篇 |
外科学 | 14篇 |
综合类 | 19篇 |
预防医学 | 14篇 |
眼科学 | 4篇 |
药学 | 49篇 |
中国医学 | 1篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 6篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 10篇 |
2013年 | 12篇 |
2012年 | 7篇 |
2011年 | 7篇 |
2010年 | 10篇 |
2009年 | 15篇 |
2008年 | 16篇 |
2007年 | 23篇 |
2006年 | 15篇 |
2005年 | 12篇 |
2004年 | 7篇 |
2003年 | 3篇 |
2002年 | 10篇 |
2001年 | 7篇 |
2000年 | 2篇 |
1999年 | 14篇 |
1998年 | 15篇 |
1997年 | 17篇 |
1996年 | 16篇 |
1995年 | 16篇 |
1994年 | 20篇 |
1993年 | 15篇 |
1992年 | 10篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 9篇 |
1987年 | 11篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 11篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 5篇 |
排序方式: 共有401条查询结果,搜索用时 15 毫秒
1.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
2.
The aim of our study was to characterize the parental perceptions of the behavioral and emotional functioning of their children and families coping with gastrointestinal motility disorders. The American Pseudo-obstruction and Hirschsprung's disease Society sponsored an educational meeting for parents of children afflicted with a variety of pediatric gastrointestinal motility disorders. During the conference, parents completed a questionnaire pertaining to the behavioral and emotional functioning of the afflicted child and other family members. Parents perceived that the child's illness was more difficult on the parents than on the affected child or their siblings. Also, parents perceived support from professionals, family, and friends increased after the children were diagnosed with pediatric gastrointestinal motility disorders. Parents worried most about the health and medical management of their afflicted child. The most common behavioral problem of the afflicted children was fear of separation, whereas the most common behavioral problem of their siblings was jealousy. The majority of referrals to mental health professionals resulted from parental emotional problems or marital discord. 相似文献
3.
4.
5.
Previous studies have shown that xenobiotic compounds such as the environmental pollutant -hexa-chlorocyclohexane (-HCH) and the synthetic sex steroid cyproterone acetate (CPA) induce growth of rat liver by hypertrophy and hyperplasia. After withdrawal of the growth stimuli, liver hypertrophy was usually found to be readily reversible. Conflicting observations were made concerning the fate of liver hyperplasia: hepatic hyperplasia persisted when induced by -HCH but was found to be partially reversible when induced by CPA. The present study confirms the reversibility of hepatic hyperplasia induced by CPA in rats: about 30% of liver DNA present at maximal liver enlargement disappeared within 6 days after cessation of CPA treatment. Simultaneously, a dramatic increase in the rate of cell elimination by apoptosis was found. Glutamate-pyruvate transaminase and alkaline phosphatase in serum did not show major increases, suggesting that cell death was not due to lytic membrane damage. Furthermore, if treatment with CPA was continued or resumed, the enhanced DNA content persisted and the number of apoptotic bodies was greatly reduced. These observations suggest that the occurrence of cell death is due to withdrawal of the growth stimulus CPA. It may reflect a regulatory phenomenon serving to maintain homeostasis of cell number.Further studies showed that CPA is rapidly eliminated from rat liver and serum: t 1/2 in the liver is about 11 h. In contrast, -HCH was previously found to be eliminated more slowly: t 1/2 approximately 144 h. The present study revealed that -HCH, CPA and nafenopin lower the number of apoptotic bodies. This suggests that inducers of liver growth can inhibit hepatocellular death by apoptosis. It is concluded that the regression of hyperplasia after CPA withdrawal may be due to its rapid elimination. On the other hand the relatively long persistence of -HCH may result in inhibition of cell death and thereby stabilize hepatic hyperplasia.Abbreviations CPA
cyproterone acetate
- -HCH
-hexachlorocyclohexane
- PB
phenobarbital
- NAF
nafenopin
- AB
apoptotic body
- b.w.
body weight
- p. admin.
post-administration
- GPT
glutamate-pyruvate transaminase
- ALP
alkaline phosphatase
Dedicated to Professor W. Koransky on the occasion of his 65th birthday 相似文献
6.
7.
Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
8.
9.
10.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献