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91.
Most gonadotropes in the pituitary of male Suncus murinus L. are immunostained with both LH beta and FSH antisera, whereas only a few gonadotropes are positive only for LH beta. The former gonadotropes consist of polygonal or polyhedral cells of medium size, and can be identified by the presence of two types of secretory granules of low density: smaller ones (about 150-250 nm in diameter) which are spherical in shape, and larger ones of irregular form with a maximum diameter of about 1,500 nm. The endoplasmic reticulum is not prominent, while the Golgi apparatus is distinct. Mitochondria are found throughout the cytoplasm but are often concentrated in and around the region of the Golgi apparatus. These fine structural features are somewhat similar to those of the classical Barnes "FSH cells" and Kurosumi-Oota "FSH cells".  相似文献   
92.
Clinical significance of reverse redistribution on thallium image was evaluated in 54 patients who had undergone PTCA. Thallium SPECT imaging was performed one week and three to six months after PTCA. Reverse redistribution was detected eight of 54 patients one week after PTCA and five of 38 patients three to six months after PTCA. In the segments with reverse redistribution, reduced regional wall motion and lesser degree of coronary stenosis was common features (p less than 0.05) angiography. In conclusion, reverse redistribution had a tendency to appear in the region with mild myocardial injury and relatively high coronary blood flow after PTCA. But in cases with new occurrence and disappearance of reverse redistribution during follow up period, we can not assess the factors to explain these phenomena. In these segments, "coronary flow reserve", "stunned myocardium", "hibernating myocardium" or other factors may be related.  相似文献   
93.
The histogenesis of stromal cells in hemangioblastoma is inconclusive despite a long-term controversy. An immunohistochemical and ultrastructural study was conducted for 17 cases of cerebellar hemangioblastoma. A wide range of immunohistological markers, targeting epithelial, mesenchymal, endothelial and neuroectodermal tissues, was used. In all cases, the microscopic hallmark characterizing hemangioblastomas, that is, lipid-containing stromal cells and a fine capillary network, known as a reticular variant, was noted. Stromal cells showed a variable immunoreactivity for neuroectodermal markers, such as S-100 protein, CD56, CD57, CD99, and neuron-specific enolase. This result, in conjunction with the absence of immunoreactivity for epithelial, mesenchymal, and endothelial markers, likely suggests neuroectodermal differentiation of stromal cells. In three cases, another component, known as a cellular variant, where epithelioid tumor cells were arranged in nests encircled by capillaries and/or in pseudorosette-like structures, was noted. Glial fibrillary acidic protein-immunoreactivity, which was totally absent in cases only showing the reticular pattern, was noted in two of them, suggesting a distinctive sign of glial differentiation in a proportion of hemangioblastomas. Ultrastructurally, microvilli-like projections in intracytoplasmic vacuoles were demonstrated in stromal cells. This result, taken together with the neuroectodermal hypothesis of stromal cells, suggests that hemangioblastomas may occasionally exhibit morphological similarities to ependymomas.  相似文献   
94.
Three distinct T-cell precursors: bone marrow cells that express low levels of the Thy-1 antigen but no lineage markers (Thy-1-lo/BM); CD4-, CD8-, and CD3- thymocytes that express low levels of the Thy-1 antigen (Thy-1-lo/Thym); and CD4-, CD8-, and CD3- thymocytes that express high levels of the Thy-1 antigen and the IL-2 R alpha chain (Thy-1+/IL2R+) were isolated by fluorescence-activated cell sorter (FACS). These three populations expanded with different kinetics in the thymus of irradiated recipient mice after intrathymic transfer. When a high dose of human recombinant IL-2 (r-IL-2) or human recombinant IL-6 (r-IL-6) was administered, r-IL-6 accelerated donor Thy-1+/IL2R+ to differentiate, whereas r-IL-2 blocked normal differentiation and expansion of donor Thy-1-lo/Thym, but did not show any significant effect on donor Thy-1+/IL2R+. Neither r-IL-2 nor r-IL-6 worked directly on donor Thy-1-lo/BM in this transfer system.  相似文献   
95.
Genetic restriction on the expression of delayed-type hypersensitivity (DTH) to Salmonella typhimurium in mice transferred passively with immune spleen cells was studied. After the intravenous transfer of immune C3H/HeJ (H-2Ik) cells into A.TL (H-2Ik) or A.TH (H-2Is) mice, footpad DTH responses could be evoked in the A.TL recipients, but not in the A.TH mice. When the immune cells of BALB/c or C3H/He mice were intravenously-transferred into F1 hybrids produced by mating BALB/c and C57BL/6 or C3H/He and C57BL/6, respectively, no DTH response could be evoked in these F1 hybrids that received immune parental cells. Local transfer as well as systemic intravenous transfer of immune parental cells to F1 haplotype recipients did not cause any DTH. Previous treatment of the F1 hybrid recipients with cyclophosphamide did not result in the expression of the DTH response. Transfer of immune F1 spleen cells into parental strains also did not induce DTH. When the immune cells of parental strains were transferred into F2 mice and into back-cross mice, examination of the DTH response in these mice showed that some of them did not have any obvious footpad swelling, while others revealed various magnitudes of swelling. The resistance of F1 hybrids to transfer of DTH is discussed.  相似文献   
96.
To investigate the effects of polymorphisms in the ATP-binding cassette transporter A1 (ABCA1) gene on the high-density lipoprotein cholesterol (HDL-C) level and the incidence of myocardial infarction (MI), we performed association studies. Sequence analysis identified 14 polymorphisms in the promoter region of ABCA1. After considering linkage disequilibrium, three polymorphisms in the promoter region and 11 polymorphisms from the JSNP database were determined in 1,880 subjects recruited from the Suita Study, representing the general population in Japan. We evaluated the association between the ABCA1 genotype and HDL-C level adjusted not only for standard factors, but also for genetic factors including ApoA1 and ApoE genotypes. Of the 14 polymorphisms tested, the G(–273)C (P=0.0074), C(–297)T (P=0.0195), and IMS-JST071749 (P=0.0093) polymorphisms were significantly associated with the HDL-C level in the Suita population. We could reconfirm that the G(–273)C genotype was influential in another set of subjects (P=0.0310, n=743). However, the distribution of the ABCA1 G(–273)C genotype in subjects with MI (n=598) was not different from that in the control population (n=801). These results indicate that ABCA1 G(–273)C has a significant effect on the HDL-C level in the general Japanese population, but not on the incidence of MI.  相似文献   
97.
98.
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security.  相似文献   
99.
Summary: Bis(phenoxy‐imine) Zr complexes with MAO activation can produce polyethylenes with well‐defined bimodal molecular weight distributions. Polymerization behavior indicates that minor changes in the ligand structures can have a significant effect on the modality of the resulting polyethylenes. Although there is no direct relationship between the bimodal catalytic behavior and the structure of a precatalyst complex in solution, a precatalyst complex having a methyl or methoxy group para to the phenoxy‐oxygen inclined to exhibit bimodal behavior whereas that with a pentafluorophenyl group on the imine‐nitrogen displayed unimodal behavior. Polymerization results suggest that bimodal behavior is linked to the presence of two kinds of cationic active species, which arise from different modes of ligand coordination. A qualitative correlation was found between the calculated amounts of possible cationic active species and the uni‐ and bimodal catalytic behavior. Based on the results obtained, we concluded that the bimodal polyethylenes are produced by two kinds of cationic active species having two available cis‐located sites with cis‐N, trans‐O and cis‐N, cis‐O arrangements. The results introduced herein are rare examples of the production of well‐defined bimodal polyethylenes using a single precatalyst.

Bis(phenoxy imine) Zr complexes can produce well‐defined bimodal polyethylenes.  相似文献   

100.
BACKGROUND: Histologic and immunohistologic features of nasal polyps (NP) are similar to those observed in asthma, thus suggesting a similar immunopathology. OBJECTIVE: The primary objective of this study was to further understand the anti-inflammatory and immunoregulatory effects of locally delivered corticosteroids. To this end, the effect of intranasal budesonide on the expression of specific cytokines, lymphocyte subsets, and epithelial remodeling in this model of airway tissue inflammation were studied. METHODS: We used immunohistochemical techniques to examine nasal mucosae (NM) from healthy individuals and nasal polyp (NP) tissues from patients with nasal polyposis obtained before and after intranasal budesonide treatment. RESULTS: First, the density of CD8(+) cells was markedly increased in NP tissues after intranasal budesonide treatment from 16.1 +/- 8.4 (M +/- SEM) per mm(2) to 39.9 +/- 24.1. Second, the density of cells immunoreactive for IL-4, IL-5, IFN-gamma, IL-12, and TGF-beta in NP was significantly greater than in control NM tissues. The density of IL-4(+) and IL-5(+) cells in NP tissues significantly decreased after budesonide treatment from 40 +/- 12 to 17.8 +/- 8 and from 19.3 +/- 11 to 10.4 +/- 7, respectively. In contrast, the density of IFN-gamma(+) and IL-12(+) cells remained unchanged. In addition, we found that the density of TGF-beta(+) cells significantly increased after intranasal budesonide from 18 +/- 5 to 41 +/- 9. Third, damage to the entire length of the NP epithelium was quantified using a grading system. The epithelium of untreated NP was substantially damaged; remarkable epithelial restitution with no apparent changes in stromal collagen deposition was observed after intranasal budesonide treatment. CONCLUSIONS: These findings demonstrate that intranasal budesonide induced an increase in CD8 population and a selective regulatory effect on tissue cytokine expression. Furthermore, intranasal budesonide promoted epithelial remodeling. We hypothesize that these immunoregulatory and remodeling effects elicited by steroids might be, at least in part, mediated by the induction of TGF-beta.  相似文献   
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