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151.
The enzyme aromatase Is Involved In the conversion of androgens to estrogens and in the modulation of various androgenlc and estrogenlc actions. Abnormalities of estrogen metabolism have been postulated to play roles in the development and/or pathophyslology of Sjdgren's syndrome. In the present study, aromatase was immunolocal-ized In 75 cases of Inflammatory disorders of human minor salivary glands of the lower lip. These included cases of primary Sjögren's syndrome (19 cases), of chronic slaladenitis (34 cases) and of mucous extravasation cysts (22 cases), in order to clarify the possible involvement of in situ estrogen production in primary Sjögren's syndrome. Aromatase Immunoreactlvlty was detected In myoepithelial cells of acini and in interstitial cells adjacent to acini and ducts In 13/19 (68%) cases of primary Sjögren's syndrome. In contrast, aromatase expression was detected In only six of 34 (18%) cases of chronic sialadenttis and in seven of 22 (32%) cases of mucous extravasation cyst. These results suggest that Increased aromatase expression in minor salivary glands with primary Sjogren's syndrome in premenopausal women may be involved in the biological features of primary Sjogren's syndrome through the production of estrogens in situ and possibly through the aggravation of the inflammatory reaction.  相似文献   
152.
153.
Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers.  相似文献   
154.
在休克过程中,体内活性氧代谢与细胞内钙超负荷存在着相互影响。为了研究林克和复苏过程中钙拮抗剂对脂质过氧化的影响,用17只杂种犬快速放血使平均动脉压为5.32kpd,并维持90min。然后回输全部失血。在休克30min时,各组别静脉注射(15min内)硫氮酮(40g/kg·min ̄(-1)),异搏定(10μg/kg·min ̄(-1)),或等量生理盐水。复苏后150min处死动物,取心、肝、肺、肾、胰和小肠组织备检。结果显示,用硫氮酮和异搏定治疗组,各主要脏器组织中黄嘌呤氧化酶活性和丙二醛含量均显著低于休克对照组。而各检测组织中超氧化物歧化酶活性变化不一。这些资料显示钙拮抗剂抗休克的机制与其阻滞Ca2+内流,降低组织中黄嘌呤氧化酶活性,抑制脂质过氧化有密切关系。  相似文献   
155.
Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and punctureinduced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction.  相似文献   
156.
To circumvent the reconstructive disadvantages inherent in resorbable polyglycolic acid (PGA)/polylactic acid (PLA) used in cartilage engineering, a nonresorbable, and nonreactive polyurethane sponge (Tecoflex sponge, TS) was studied as both a cell delivery device and as an internal support scaffolding. The in vitro viability and proliferation of porcine articular chondrocytes (PACs) in TS, and the in vivo generation of new articular cartilage and long-term resorption, were examined. The initial cell attachment rate was 40%, and cell density increased more than 5-fold after 12 days of culture in vitro. PAC-loaded TS blocks were implanted into nude mice, became opalescent, and resembled native cartilage at weeks 12 and 24 postimplantation. The mass and volume of newly formed cartilage were not significantly different at week 24 from samples harvested at week 6 or week 12. Safranin O-fast green staining revealed that the specimens from cell-loaded TS groups at week 12 and week 24 consisted of mature cartilage. Collagen typing revealed that type II collagen was present in all groups of tissue-engineered cartilage. In conclusion, the implantation of PAC-TS resulted in composite tissue-engineered articular cartilage with TS as an internal support. Long-term observation (24 weeks) of mass and volume showed no evidence of resorption.  相似文献   
157.
Proteoglycans are involved in secondary palate formation. In the present study, we focused on two small leucine-rich proteoglycans, decorin and biglycan, because they assembled extracellular matrix molecules such as collagens and modulated signaling pathway of transforming growth factor-beta. To investigate the functions of decorin and biglycan in palatogenesis, we compared their mRNA expression patterns between normal palate and retinoic acid-induced cleft palate in mice by using in situ hybridization analysis during the period of embryonic day 13.5 (E13.5) to E15.5. On E13.5, decorin mRNA was expressed in the epithelia and mesenchyme on the nasal side of the developing secondary palate. During the period the palate shelves were fusing (E14.5), decorin mRNA was strongly expressed in the mesenchyme but its expression pattern was asymmetric; decorin mRNA expression area in the nasal side was broader than that in the oral side. The expression of decorin mRNA was hardly detected in the mesenchyme on either side of the medial edge epithelium. After fusion (E15.5), its expression converged to the mesenchyme just around the palatine bone. Biglycan mRNA was ubiquitously distributed throughout the palatal mesenchyme for the mid-gestation period. Its expression area became limited to the ossification area within the palate after the late gestation period. In the retinoic acid-treated mice, the area of the decorin gene expression expanded to the core region of the palate primordium where little signal was observed in control mice. On the other hand, biglycan in the retinoic acid-treated mice did not show remarkable change in its distribution patterns compared with that in the control mice. These findings suggest that decorin and biglycan play distinct roles in palatogenesis, and decorin was more actively involved in the process of secondary palate formation than biglycan. Up-regulation of decorin gene expression in the retinoic acid-treated mice might influence the pathogenesis of cleft palate.  相似文献   
158.
159.
Japanese encephalitis virus-specific IgM is a reliable indicator for serodiagnosis of Japanese encephalitis. A particle agglutination (PA) assay system was developed to detect anti-Japanese encephalitis virus IgM in human serum samples. The newly developed PA assay consisted of hydroxyapatite-coated nylon beads and V-bottom 96-well microplates. Hydroxyapatite-coated nylon beads were coated with Japanese encephalitis virus antigens. Japanese encephalitis virus antigen-coated, hydroxyapatite-coated nylon beads agglutinated in the IgM-captured wells when anti-Japanese encephalitis virus IgM-positive serum samples were used. A button pattern was formed at the bottom of the wells when anti-Japanese encephalitis virus IgM-negative serum samples were used. Thirty anti-Japanese encephalitis virus IgM-positive serum samples from Japanese encephalitis-confirmed cases were tested by the PA assay. All these serum samples were determined to be Japanese encephalitis virus IgM-positive. IgM titers determined by the PA assay corresponded to those determined by enzyme-linked immunosorbent assay. The titers were consistent in two independent PA assays. These results indicate that the newly developed PA assay is a reliable method for detecting anti-Japanese encephalitis virus IgM in human serum samples and that this assay will be a suitable diagnostic system especially in rural areas of Asia.  相似文献   
160.
Changes in the number of activated sweat glands (ASGs) and sweat output per gland (SGO) with increased exercise intensity during sustained static exercise were investigated. Fourteen male subjects performed 20, 35, and 50% maximal voluntary contraction (MVC) for 60 s with the right hand (exercised arm) at an ambient temperature of 35 degrees C and 50% relative humidity. Although sublingual, local skin, and mean skin temperatures remained essentially constant throughout the exercise at each intensity, the sweating rate (SR) of nonglabrous skin on the nonexercised left forearm increased significantly with a rise in exercise intensity (p<0.05). Changes in the number of ASGs with rising exercise intensity paralleled changes in the SR, but the SGO did not change markedly with altered exercise intensity. These results suggest that in mildly heated humans, at less than 50% MVC, the increase in the SR from nonglabrous skin with rising exercise intensity during sustained static exercise is dependent on changes in the number of ASGs and not on SGO.  相似文献   
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