全文获取类型
收费全文 | 534篇 |
免费 | 84篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 73篇 |
妇产科学 | 5篇 |
基础医学 | 94篇 |
口腔科学 | 10篇 |
临床医学 | 62篇 |
内科学 | 154篇 |
皮肤病学 | 6篇 |
神经病学 | 28篇 |
特种医学 | 28篇 |
外科学 | 38篇 |
综合类 | 37篇 |
预防医学 | 30篇 |
眼科学 | 5篇 |
药学 | 27篇 |
肿瘤学 | 22篇 |
出版年
2023年 | 3篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 9篇 |
2014年 | 17篇 |
2013年 | 15篇 |
2012年 | 16篇 |
2011年 | 16篇 |
2010年 | 19篇 |
2009年 | 22篇 |
2008年 | 21篇 |
2007年 | 22篇 |
2006年 | 17篇 |
2005年 | 15篇 |
2004年 | 14篇 |
2003年 | 17篇 |
2002年 | 18篇 |
2001年 | 16篇 |
2000年 | 13篇 |
1999年 | 13篇 |
1998年 | 24篇 |
1997年 | 24篇 |
1996年 | 20篇 |
1995年 | 9篇 |
1994年 | 18篇 |
1993年 | 16篇 |
1992年 | 14篇 |
1991年 | 10篇 |
1990年 | 18篇 |
1989年 | 14篇 |
1988年 | 17篇 |
1987年 | 13篇 |
1986年 | 16篇 |
1985年 | 12篇 |
1984年 | 9篇 |
1983年 | 13篇 |
1982年 | 3篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1979年 | 8篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1976年 | 5篇 |
1975年 | 8篇 |
1974年 | 6篇 |
1970年 | 3篇 |
排序方式: 共有623条查询结果,搜索用时 31 毫秒
1.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
2.
3.
Bursal and thymic antigenic specificities have been shown in the chicken in an immune adherence assay using cross-absorbed rabbit antisera. 相似文献
4.
Cutaneous unresponsiveness to Mycobacterium bovis BCG in intravenously infected mice. 总被引:2,自引:2,他引:2 下载免费PDF全文
Mice injected with 1 mg (about 1 X 10(7) CFU) of Mycobacterium bovis BCG in the footpad showed high levels of delayed-type hypersensitivity (DTH) to BCG antigens and a continuous increase in circulating specific anti-immunoglobulin G (IgG) antibodies throughout a 6-week observation period. In contrast, mice injected intravenously with a 1-mg dose failed to mount a DTH and showed a depression in antibody production at week 5 postinfection. A dose-response study revealed that an optimum dose of BCG, when injected intravenously, can induce a small but significant DTH response. The delayed cutaneous unresponsiveness in intravenously infected mice lasted at least 6 weeks and was not antigenically specific, in that it depressed the DTH response to Corynebacterium parvum. No simple relationship existed between levels of DTH and the amount of circulating anti-IgG antibodies. Splenectomy and treatment with a high dose of cyclophosphamide before infection, although greatly reducing the humoral response, did not reverse the BCG-induced unresponsiveness nor enhance levels of DTH in mice infected in the footpad. It is concluded that the intravenous infection of mice with BCG exerts a nonspecific inhibitory effect on delayed-type immune reactions by the induction of some type of suppressor mechanisms that are resistant to cyclophosphamide. 相似文献
5.
6.
A BALB/c congenic strain of mice that carries a genetic locus (Ityr) controlling resistance to intracellular parasites. 总被引:10,自引:14,他引:10 下载免费PDF全文
M Potter A D O''''Brien E Skamene P Gros A Forget P A Kongshavn J S Wax 《Infection and immunity》1983,40(3):1234-1235
BALB/c.DBA/2 Idh-1b-Ityr-Pep-3b congenic mice were developed by introgressively backcrossing the Idh-1b and Pep-3b markers of DBA/2 mice onto the BALB/c pi mice. This introduced a 30-centimorgan chromosome 1 segment of DBA/2 chromatin that contained the Ityr gene. BALB/c.DBA/2 Idh-1b-Ityr-Pep-3b mice were resistant to in vivo infections by Salmonella typhimurium, Mycobacterium bovis, and Leishmania donovani. 相似文献
7.
8.
Damoiseaux JG Bouten B Linders AM Austen J Roozendaal C Russel MG Forget PP Tervaert JW 《Journal of clinical immunology》2002,22(5):281-288
Both celiac disease and inflammatory bowel disease (IBD) are characterized by chronic diarrhea and the presence of distinct (auto)antibodies. In the present study we wanted to determine the prevalence of serological markers for inflammatory bowel disease, i.e., perinuclear antineutrophil cytoplasmic antibodies (pANCA) and/or anti-Saccharomyces cerevisiae antibodies (ASCA), in 37 patients with biopsy-confirmed celiac disease (Marsh IIIb/c). The majority of the patients was positive for IgA (auto)antibodies typically associated with celiac disease, i.e., antiendomysium antibodies (EMA) (86.5%), antigliadin antibodies (AGA) (73%), and antirecombinant human tissue transglutaminase antibodies (rh-tTGA) (86.5%). Four patients with selective IgA deficiency could be identified by analyzing EMA, AGA, and rh-tTGA for the IgG isotype. The prevalence of pANCA and ASCA, markers that are used for IBD, was unexpectedly high in our cohort of patients with celiac disease: 8 patients were positive for pANCA (IgG) and 16 patients were positive for ASCA (IgG and/or IgA). These results indicate that the presence of pANCA or ASCA in the serum of patients with chronic diarrhea does not exclude celiac disease. A prospective study is required to determine whether pANCA and/or ASCA identify patients at risk for developing secondary autoimmune disease. 相似文献
9.
The UTX gene escapes X inactivation in mice and humans 总被引:7,自引:3,他引:7
Greenfield A; Carrel L; Pennisi D; Philippe C; Quaderi N; Siggers P; Steiner K; Tam PP; Monaco AP; Willard HF; Koopman P 《Human molecular genetics》1998,7(4):737-742
We recently have identified a ubiquitously transcribed mouse Y chromosome
gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A
peptide derived from the UTY protein confers H-Y antigenicity on male
cells. Here we report the characterization of a widely transcribed X-linked
homologue of Uty , called Utx , which maps to the proximal region of the
mouse X chromosome and which detects a human X-linked homologue at Xp11.2.
Given that Uty is ubiquitously transcribed, we assayed for Utx expression
from the inactive X chromosome (Xi) in mice and found that Utx escapes X
chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the
mouse X chromosome have been reported previously to escape inactivation.
The human UTX gene was also found to be expressed from Xi. We discuss the
significance of these data for our understanding of dosage compensation of
X-Y homologous genes in humans and mice.
相似文献
10.
V. Nougier C. Bard M. Fleury N. Teasdale J. Cole R. Forget J. Paillard Y. Lamarre 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,109(3):473-482
Two deafferented patients and several control subjects participated in a series of experiments to investigate how accurate single-joint movements are programed, spatially calibrated, and updated in the absence of proprioceptive information. The deafferented patients suffered from a permanent and severe loss of large sensory myelinated fibers below the neck. Subjects performed, with and without vision, sequences of forearm supinations and pronations with two temporal delays between each movement (0 s and 8 s). Overall, the lack of proprioception did not yield any significant decrease in movement accuracy when vision was available. Without vision, the absence of proprioceptive afferents yielded (1) significantly larger spatial errors, (2) amplitude errors similar to those of control subjects, and (3) a significant drift when an 8-s delay was introduced between two successive movements. Subjects also performed, without vision, a 20 supination followed by a 20 pronation that brought back the wrist to the starting position. On some trials, the supination was blocked unexpectedly by way of a magnetic brake. When the supination was blocked, subjects were already on the second target and no pronation was required when the brake was released. The defferented patients, unaware of the procedure, always produced a 20 pronation. These data confirm that deafferented patients were not coding a final position. It rather suggests that they coded an amplitude and translated the spatial distance between the two targets in a corresponding force pulse. Overall, the results highlight the powerful and key role of proprioceptive afferents for calibrating the spatial motor frame of reference. 相似文献