全文获取类型
收费全文 | 203篇 |
免费 | 14篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 10篇 |
妇产科学 | 3篇 |
基础医学 | 33篇 |
口腔科学 | 5篇 |
临床医学 | 14篇 |
内科学 | 44篇 |
皮肤病学 | 2篇 |
神经病学 | 20篇 |
特种医学 | 67篇 |
外科学 | 5篇 |
综合类 | 3篇 |
预防医学 | 4篇 |
眼科学 | 2篇 |
药学 | 10篇 |
肿瘤学 | 6篇 |
出版年
2022年 | 1篇 |
2018年 | 1篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 5篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 6篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2007年 | 10篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 22篇 |
1997年 | 15篇 |
1996年 | 13篇 |
1995年 | 13篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1959年 | 2篇 |
1958年 | 1篇 |
1956年 | 5篇 |
1949年 | 2篇 |
1948年 | 1篇 |
排序方式: 共有230条查询结果,搜索用时 0 毫秒
11.
Maternal administration of granulocyte colony-stimulating factor improves neonatal rat survival after a lethal group B streptococcal infection 总被引:2,自引:0,他引:2
Novales JS; Salva AM; Modanlou HD; Kaplan DL; del Castillo J; Andersen J; Medlock ES 《Blood》1993,81(4):923-927
Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge. 相似文献
12.
M Storr P Born E Frimberger N Weigert T Rösch A Meining M Classen HD Allescher 《BMC gastroenterology》2002,2(1):19-8
Background
It has been suggested that intrasphincteric injection of botulinum toxin (BTX) may represent an alternative therapy to balloon dilatation in achalasia. The aim of the present study was to test the effectiveness of botulinum toxin injections in achalasia patients, as assessed using lower oesophageal sphincter pressure (LOSP) and symptom scores, and to compare the response in patients with different types of pretreatment (no previous treatment, balloon dilatation, myotomy, BTX injection). 相似文献13.
Patterns of cytokine gene expression in peripheral T-cell lymphoma of angioimmunoblastic lymphadenopathy type 总被引:3,自引:0,他引:3
Foss HD; Anagnostopoulos I; Herbst H; Grebe M; Ziemann K; Hummel M; Stein H 《Blood》1995,85(10):2862-2869
14.
von den Driesch P; Bhardwaj R; Flad HD; Neugebauer DC; Pielken HJ; Urbanitz D; Kolsch E 《Blood》1989,74(1):430-436
An immunoglobulin M (IgM)-positive cell line, Ms 28, apparently spontaneously transformed by Epstein-Barr virus (EBV) was established from peripheral blood cells of a patient with immature myeloblastic leukemia. It has been characterized according to phenotype, cytochemistry, and membrane antigen pattern. The cell line expresses lymphoid markers like CD 19, CD 22, and CD 30 and synthesizes and secretes IgM. Monocyte markers CD 11c, CD 14, and CD 15 are absent. Neither interleukin-1 (IL-1), nor tumor necrosis factor (TNF-alpha) are produced. But Ms 28 cells show strong phagocytic activity and engulf Latex particles and sheep RBCs (SRBCs) that need not to be opsonized. The phagocytic activity can be inhibited by chloroquine. Both phagocytosis and EBV nuclear-antigen (EBNA) expression can be observed in one and the same cell. Ms 28 cells might be useful to study immunologic activities like antigen processing and presentation. 相似文献
15.
Large‐scale brain network abnormalities in Huntington's disease revealed by structural covariance 下载免费PDF全文
Lora Minkova Simon B. Eickhoff Ahmed Abdulkadir Christoph P. Kaller Jessica Peter Elisa Scheller Jacob Lahr Raymund A. Roos Alexandra Durr Blair R. Leavitt Sarah J. Tabrizi Stefan Klöppel TRACK‐HD Investigators 《Human brain mapping》2016,37(1):67-80
Huntington's disease (HD) is a progressive neurodegenerative disorder that can be diagnosed with certainty decades before symptom onset. Studies using structural MRI have identified grey matter (GM) loss predominantly in the striatum, but also involving various cortical areas. So far, voxel‐based morphometric studies have examined each brain region in isolation and are thus unable to assess the changes in the interrelation of brain regions. Here, we examined the structural covariance in GM volumes in pre‐specified motor, working memory, cognitive flexibility, and social‐affective networks in 99 patients with manifest HD (mHD), 106 presymptomatic gene mutation carriers (pre‐HD), and 108 healthy controls (HC). After correction for global differences in brain volume, we found that increased GM volume in one region was associated with increased GM volume in another. When statistically comparing the groups, no differences between HC and pre‐HD were observed, but increased positive correlations were evident for mHD, relative to pre‐HD and HC. These findings could be explained by a HD‐related neuronal loss heterogeneously affecting the examined network at the pre‐HD stage, which starts to dominate structural covariance globally at the manifest stage. Follow‐up analyses identified structural connections between frontoparietal motor regions to be linearly modified by disease burden score (DBS). Moderator effects of disease load burden became significant at a DBS level typically associated with the onset of unequivocal HD motor signs. Together with existing findings from functional connectivity analyses, our data indicates a critical role of these frontoparietal regions for the onset of HD motor signs. Hum Brain Mapp 37:67–80, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
16.
SJ KANG HD WOO JY CHOI YJ LEE HW CHUNG 《中国药理学与毒理学杂志》2006,20(3):224-247
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins. 相似文献
17.
Dehydroepiandrosterone (DHEA) is an intermediate product in the synthesis
of male and female sex hormones in the adrenal cortex of man. In livers of
rats and mice DHEA increases the levels of cytochrome P450 IVA and
peroxisomal beta-oxidation enzymes associated with peroxisome
proliferation. Prolonged treatment of rats with DHEA induces liver tumors
that are more frequent in females arising mainly in the periportal regions
of the liver lobule (Metzger et al., Toxicol. Pathol. 23, 591-605, 1995).
Because of paucity of information on hepatic zonation of peroxisomal
response to DHEA and controversial reports on gender-specific differences
of its effects the present study was undertaken using qualitative
immunohistochemical and quantitative immunoelectron microscopical
techniques in addition to Western blotting. Rats were treated for 24 weeks
with 0.6% DHEA supplied with diet. Immunoblot analysis revealed marked
induction of peroxisomal beta- oxidation enzymes, which by quantitative
analysis was equally strong in male and female animals, whilst catalase and
urate-oxidase were not increased. Cytochrome P450 IVA, in contrast, was
induced significantly stronger in male than in female rats.
Immunohistochemistry confirmed the induction of cytochrome P450 IVA showing
a marked lobular gradient in female animals with strong induction in
pericentral and almost no induction in periportal regions of the liver
lobule. In male animals cytochrome P450 IVA was expressed more uniformly
across the liver lobule. A similar sex specific zone-dependent response was
observed for peroxisomes. DHEA induced in females a significant zonal
gradient with marked peroxisome proliferation and a strong induction of
peroxisomal hydratase/dehydrogenase in pericentral hepatocytes and a much
smaller response in periportal regions. Livers of male animals, in
contrast, showed a uniform peroxisomal proliferation to DHEA with only
slight zonal differences. The striking homologies of the induction patterns
of cytochrome P450 IVA and the peroxisome proliferation in both sexes
support the notion of a functional relationship. In view of the almost
exclusive periportal localization of DHEA-induced tumors in female rats in
contrast to the pericentral localization of the peroxisomal proliferation
shown by this study, it seems likely that other factors in addition to
peroxisome proliferation may contribute to the hepatocarcinogenic effect of
DHEA.
相似文献
18.
19.
Venous clots: evaluation with MR imaging 总被引:2,自引:0,他引:2
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi. 相似文献
20.
Hydrocephalus was induced in 12-day-old rats by the cisternal infusion of concentrated kaolin suspension. At 19 days of age, a lesion, 100 or 150 μm in diameter, was made in the ependymal lining of the lateral ventricles. Animals were killed at intervals from 1 h to 20 days after the lesion was made. The damaged area was examined by scanning electron microscopy, light and transmission electron microscopy. Between 1 h and 48 h the hole was still open. Small round cells, identified as free subependymal cells, were associated with the edges of the hole from 1 h after the lesion was made. From 48 h, the lesion was completely covered with cell bodies and their processes and no hole was present. Signs of differentiation were seen in the free subependymal cells from 4 days, the cells becoming more electron lucent. By 15 days, three types of cell arrangement were seen within the damaged area: 1 clusters of small cells, with few processes, resembling subependymal cells; 2 small numbers of cells with flat cytoplasmic processes which formed the lining of the ventricular wall; 3 clusters of cells with long thin processes attached to the surface of the ventricular wall but not forming the ependymal lining. The results of this study suggest that, in the hydrocephalic brain, ependymal damage and the repair of a defect within the ventricular wall is initiated by subependymal cells. 相似文献