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51.
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Rapid titration of varicella-zoster virus (VZV) in human embryonic fibroblasts (HEF) based on staining of virus-infected cells by indirect immunoperoxidase technique (IPA) is described. Cell monolayers were grown in wells of plastic plates (two different diameters). Foci of virus-infected cells as revealed by IPA could be counted either 48 hr post-infection, if cell-associated virus (VZV infected cells) was used as inoculum, or 72 hr p. i. if cell-free virus was used. A linear relationship was observed between virus dilution and number of foci. The first virus was detected 12 hr p. i., the highest titre at 36 hr, when cytopathic effect (CPE) involved about 50% of the monolayer.  相似文献   
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Summary The blood supply of 50 facial nerves was examined during a micro-anatomical study of the ponto-cerebellar angle using injections of colored latex or Chinese ink.The results indicate the presence of a double arterial blood supply: the proximal supply, rising at the level of the brain stem, results from the confluence of three to five arterioles originating from the anterior inferior cerebellar artery or from the basilar artery itself; the distal supply at the level of the internal acoustic meatus arises from the labyrinthine artery.These two arterial systems do not anastomose directly but by way of capillaries of less than 200 microns in diameter.From these findings the authors conclude that certain postoperative facial paralyses, which may arise in spite of the conservation of the nerve, are in fact ischemic in nature.
Etude micro-anatomique de la vascularisation artérielle du nerf facial dans l'angle ponto-cérébelleux
Résumé Dans le cadre d'une étude micro-anatomique de l'angle ponto-cérébelleux, la vascularisation de 50 nerfs faciaux est examinée sous microscope opératoire après injection au latex coloré ou à l'encre de Chine.Cette étude permet aux auteurs de décrire un double apport artériel: l'un proximal, né au niveau du tronc cérébral, résulte de la confluence de 3 à 5 artérioles issues de l'ACiA ou de l'artère basilaire ellemême; l'autre distal, au niveau du méat acoustique interne, provient de l'artère labyrinthique. Ces deux systèmes artériels ne s'anastomosent pas entre eux à plein canal, mais par des capillaires d'un diamètre inférieur à 200 microns.Les auteurs en tirent argument pour estimer que certaines paralysies faciales post-opératoires survenant malgré la conservation anatomique du nerf, sont de nature ischémique.
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54.
The natural ligands of the S100 EF hand proteins S100A8 and A9 [myeloid-related proteins 8 and 14] have long been searched for in order to further the understanding of the role of the S100A8/A9-expressing monocyte subpopulation in progressing inflammatory processes. We demonstrate that S100A8, S100A9 and the S100A8/A9 heterodimeric complex bind to human dermal microvascular endothelial cell line (HMEC)-1 with an increasing binding capacity progressing from S100A8 < or = S100A9 < or = S100A8/A9. Similar results were obtained in the apolipoprotein E knockout mouse model, where preferably recombinant S100A9 but no S100A8 bound to the endothelium of the aorta ascendens. The binding of the S100A8/A9 heterodimer complex to activated HMEC-1 is specific as demonstrated by a dose-responding and satiable binding curve and the competition of FITC-labeled versus unlabeled protein. The protein character of the binding site was proven by treatment with trypsin. S100A8/A9 binding to HMEC-1 is inducible by lipopolysaccharide and tumor necrosis factor-alpha, and in the presence of calcium. A 163-kDa protein was isolated from a cell lysate of activated HMEC-1 cells using an affinity-chromatography protocol. The endothelial cell-associated ligand proteins isolated by the use of the S100A9 monomer and the S100A8/A9 dimer were subjected to mass spectrometry for protein identification. Clearly, alpha(2)-macroglobulin was identified as a binding partner for the S100A9 monomer, whereas no protein could be identified from the database for the ligand of the S100A8/A9 dimer.  相似文献   
55.
The development of the human immune system during embryonic and fetal life has historically been difficult to research due to limited access to human tissue. Experimental animal models have been widely used to study development but cellular and molecular programmes may not be conserved across species. The advent of multiomic single-cell technologies and an increase in human developmental tissue biobank resources have facilitated single-cell multiomic studies focused on human immune development. A critical question in the near future is "How do we best reconcile scientific findings across multiple omic modalities, developmental time, and organismic space?" In this review, we discuss the application of single-cell multiomic technologies to unravel the major cellular lineages in the prenatal human immune system. We also identify key areas where the combined power of multiomics technologies can be leveraged to address specific immunological gaps in our current knowledge and explore new research horizons in human development.  相似文献   
56.
Known brain manifestations of tuberous sclerosis (TSC) are cortical sclerotic tubera, giant cell astrocytomas, subependymal calcified nodules in the lateral walls of the lateral ventricles, and white matter heterotopias. In addition, small cyst-like lesions in the white matter have been described. We report on three TSC patients with hitherto undescribed large cyst-like cerebral lesions in subcortical and white matter locations. We emphasize that cystoid brain degeneration is a rare but typical cerebral manifestation of TSC and suggest that, in patients with such lesions, TSC should be taken into consideration.  相似文献   
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OBJECTIVES: Lipoprotein(a) (Lp(a)) and homocysteine (Hcy) are independent cardiovascular risk factors, which have been shown to be lowered by hormone replacement therapy (HRT). In this 2-year study, the long-term effects of raloxifene (Rlx) in two doses, on Lp(a) and Hcy, were studied and compared with the effects of continuously combined hormone replacement therapy (ccHRT). METHODS: In a prospective, randomized, double-blind, placebo-controlled 2-year study, 95 healthy, non-hysterectomized, early postmenopausal women, received daily either oral Rlx 60 mg (N=24) or 150 mg (N=23), ccHRT (conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 2.5 mg; N=24) or placebo (N=24). Fasting serum Lp(a) and plasma Hcy concentrations were measured at baseline and at 6, 12 and 24 months. RESULTS: The mean individual changes compared to baseline after 24 months were for Lp(a): Rlx 60: - 5%, Rlx 150: -7%, ccHRT: -34%, placebo: +1% and for Hcy: Rlx 60: -3%, Rlx 150: -4%, ccHRT: -4%, placebo: +6%. ANCOVA was significant for Lp(a) under ccHRT versus placebo (P=0.001) and for Lp(a) under ccHRT versus each of the two Rlx groups (P<0.05). CONCLUSIONS: Long-term treatment with Rlx was not as effective as ccHRT in lowering Lp(a). Although not significant and without an obvious dose-related response, the Hcy values showed the same trend for each treatment arm, which is in line with data reported earlier.  相似文献   
59.
Nociceptive neurons of the raccoon lateral thalamus   总被引:1,自引:0,他引:1  
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60.
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