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91.
Pulmonary granulomas induced in rabbits by the endobronchial instillation of mycobacterial chemical fractions were re-examined for eosinophilic infiltration. Delayed type hypersensitivity reactions either of tuberculin type or of wax D type did not induce but rather suppressed eosinophilic infiltration in the inflamed area, although some peptidoglycans which are antigenic for the induction of immediate hypersensitivity and fatty acid fractions were weak stimulators of eosinophilic infiltration. Bacterial endotoxin, LPS, was a potent stimulator. It was found that some long chain fatty acids can cause severe eosinophilic infiltration in the induced granulomas. Arachidonic acid was the most active of those examined, so the activity of its metabolites was tested and PGE2 was found to be most active. As the eosinophilic infiltration was markedly suppressed in animals treated with a cyclooxygenase inhibitor (aspirin), the stimulators of eosinophilic infiltration were not fatty acids themselves but their metabolites, PGE2 and some others. The site of permeation of eosinophils from the circulation was found to be arteriolar in the inflamed lung. The granulomatous lesion with eosinophilic infiltration in rabbits is discussed to shed light on the aetiology of eosinophilic granuloma in the human lung.  相似文献   
92.
Renal glomerulogenesis in medaka fish, Oryzias latipes   总被引:2,自引:0,他引:2  
We provide an overview of glomerulogenesis in medaka from the embryo to the adult by means of in situ hybridization with the wt1 gene as a marker as well as histology and three-dimensional images. The pronephric glomus starts to develop in the intermediate mesoderm during early somitogenesis, is completed before hatching, and persists throughout the lifetime of the fish. Within 5 days after hatching, mesonephric glomerulus formation begins in the caudomedial end of the pronephric sinus and duct area. The number of glomeruli reaches approximately 200-300 in each kidney within 2 months after hatching. wt1 expression during nephron maturation served as a marker for the formation of the mesenchymal condensate and the nephrogenic body. Existence of mesenchymal condensates and persistence of wt1 expression in the adult kidney suggest that the mesonephros retains precursor cells that may be capable of contributing to neoglomerulogenesis during adulthood. Developmental Dynamics 237:2342-2352, 2008. (c) 2008 Wiley-Liss, Inc.  相似文献   
93.
Summary Biological and biochemical characters of seven enterovirus 71 (E71) isolates were compared. Four isolates (two from patients with hand, foot and mouth disease [HFMD] and two from patients with encephalitis) grew in cynomolgus monkey kidney cells both at 39.5 and 35° C. However, the remaining three strains (from patients with HFMD) grew at 35° C, but not at 39.5° C. Three temperature-resistant and two temperature-sensitive strains were tested for neurovirulence in monkeys. Temperature-resistant strains were shown to be neurovirulent, whereas temperature-sensitive strains were less neurovirulent. The results suggest correlation between temperature-sensitive growth and neurovirulence in monkeys of E71. Variation in the electrophoretic mobility of the viral polypeptides was detected in three out of seven strains. The fingerprinting of oligonucleotides generated from the viral genome showed similar patterns in two isolates from patients with HFMD and one from patient with encephalitis and variable patterns in each genomic map of remaining four strains. These variations of polypeptide patterns and of oligonucleotide maps could not be correlated with pathogenicity (encephalitis or HFMD), temperature-sensitive growth and neurovirulence in monkeys.With 4 Figures  相似文献   
94.
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.  相似文献   
95.
96.
Imogolite, a natural product in the clay fraction of Japanese soil, was characterized through its dilute solution properties. Various methods were employed for this characterization, including viscosity, sedimentation, static/dynamic light scattering, and small angle X-ray scattering. All these measurements have revealed consistently that imogolite is represented by a rigid thin rod within the accuracy of available theories, where its repeat unit is composed of twelve gibbsite units. Since the evaluation of the chain length from the observed quantities depends on the molecular weight distribution, its effect was also considered where Mw/Mn ≈ 1,2 was estimated from the sedimentation profile.  相似文献   
97.
P15E is a specific sequence among the envelope gene (env)-encoded transmembrane proteins of exogenous and endogenous retroviruses. A synthetic peptide (CKS-17) that shows homology to this p15E region in several species of retrovirus is known to induce immune abnormalities. In this study, we examined the effect of a synthetic peptide derived from a region of human endogenous retrovirus (HERV) clone 4-1 ( 4-1) similar to sequences of CKS-17 on the induction of systemic lupus erythematosus (SLE)-related immune abnormalities. Our results indicated that this peptide could induce T-cell activation and anergy in normal peripheral blood mononuclear cells, and the peptide could also promote the production of interleukins IL-6 and IL-16. These phenomena are representative immune abnormalities observed in SLE patients. Thus, our findings support the possibility that HERV acts as a pathogen in human SLE.  相似文献   
98.
Most enzymes in serum that are measured in clinical laboratories can occur in macro-molecular forms in a significantly number of patients. Within dry chemistry (DC) multilayer film, physical barriers may prevent contact macro-molecular enzyme forms with the active reagent ingredients. Here, serum samples with macro-creatine kinase (macro-CK) type 1: CK-immunoglobulin complex or type 2: oligomer mitochondrial CK (CKm) were analyzed for total CK activity on three different DC analyzers: VITROS 700XR, FUJIDRYCHEM 5000, SPOTCHEM SP4410 and a classic wet chemistry (WC) analyzer: HITACHI 7350. Macro-CKs were detected and identified by electrophoresis on cellulose acetate. Serum with high amounts of oligomer CKm gave CK values by all of DC methods significantly lower than that by the WC method (p < 0.05). Oligomer CKm gradually converts into monomer forms in serum after storage. With increase in day after storage at 4 degrees C, there was a gradual shift in which percent of total CK activity for oligomer CKm decreased while the ratio of total CK activity, DC method/WC method increased. The principle of analytical method for CK activity determination is commonly to all of the DC methods, the WC method and the electrophoretic analysis. These suggest that oligomer CKm is sieved by DC multilayer film elements. In contrast, each of DC method produced highly corrected CK activities for sample containing CK-immunoglobulin complex. This difference in the effects of macro-CKs may depend upon physicochemical characteristics of analytical DC elements.  相似文献   
99.
100.
A 51-year-old woman underwent orthotopic liver transplantation because of a small-duct primary sclerosing cholangitis associated with chronic ulcerative colitis and a hepatoportal arteriovenous fistula. Arteriograms before liver transplantation and specimen arteriograms revealed a convolution of arteries in the right hepatic lobe which communicated with a massively dilated and partly thrombosed portal vein branch. The lesion was probably the result of a previous liver biopsy. Microscopic examination of the fistula and of specimens taken at a distance from the fistula showed prominent intimal fibroplasia of portal vein branches. The vascular changes were so severe that hepatic artery and portal vein branches closely resembled each other on routine sections. We are unaware of such a finding in other conditions and therefore believe that recognition of the described vascular abnormalities in liver biopsy specimens should lead pathologists to comment that an arterioportal fistula might be present.  相似文献   
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