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31.
We have cloned, sequenced and expressed a cDNA encoding the alpha-chain of feline CD8. This clone, named FT8-10, has an open reading frame with 720 nucleotides in length encoding a protein with 239 amino acid residues. Sequence analysis has revealed that the feline CD8 alpha-chain (CD8 alpha) shares significant homology with human (T8/Leu-2), bovine (BoCD8), rat (MRC OX8) and mouse (Lyt-2) CD8 alpha subunits. Cysteine residues as well as the tyrosine kinase p56lck binding site are well conserved. Besides, no putative N-linked glycosylation site was found. Interestingly, immunofluorescence analysis of COS-7 cells transfected with feline CD8 alpha expression plasmid driven by SR alpha promoter showed that the expressed feline CD8 alpha cross-reacted with an anti-human CD8 alpha monoclonal antibody OKT8, but did not react with an anti-feline monoclonal antibody, FT-2, which is thought to recognize the feline analogue of the human T8/Leu-2 and murine Lyt-2 molecules expressed on cytotoxic/suppressor T cells.  相似文献   
32.
Polymerizations of malealdehyde were carried out with alkalimetal alkoxides, AlEt3, pyridine, AlEt3? TiCl4 and BF3OEt2 as catalysts. All the polymers obtained with other catalysts than AlEt3 and AlEt3? TiCl4 were composed only of the cyclized unit (dialkoxydihydrofuran ring) (> 95%) and the 1.2-addition structure (< 5%). IR spectra of the polymers obtained with AlEt3 and AlEt3? TiCl4 catalysts were suggestive of the presence of five-membered lactone rings which may occur as a result of termination by hydride transfer. The steric structure (cis vs. trans) of the dialkoxydihydrofuran ring in polymer was inferred from the comparison of the IR spectra of the polymer with those of the isomeric dialkoxydihydrofurans in the 800 cm?1 region. Anionic catalysts gave higher contents of the cis configuration, while coordinated anionic catalysts gave comparable amounts of the cis and trans structures.  相似文献   
33.
Summary To investigate whether the feline CD 4 (fCD 4) molecules are involved in infections of highly lymphotropic feline immunodeficiency virus (FIV) isolates, we expressed fCD 4 stably on Crandell feline kidney cells andFelis catus whole foetus 4 cells by transfection of a cDNA encoding the fCD 4 glycoprotein, and then infected them with TM 1 and TM 2 strains of FIV, which are unable to infect these cells productively. In spite of fCD 4 being expressed on these cells, no virus production was observed. This result indicates that fCD 4 expression alone cannot induce a productive infection of the FIV TM 1 and TM 2 strains.  相似文献   
34.
A case of mucinous cystadenoma mimicking ovarian cancer is reported. Serum carcinoembryonic antigen (CEA) concentration was raised, and computed tomography of the abdomen and pelvis demonstrated a long oval shaped cystic mass measuring 9 cm in length on the right anterior side of the uterus. Because of possible right ovarian cancer, laparotomy was performed and the mass was found to be a mucinous cystadenoma of the appendix. This case indicates that mucinous cystadenoma of the appendix may show an unusual presentation including its location as well as the high serum CEA, mimicking ovarian cancer. Therefore, gynaecologists as well as gastroenterologists should consider its possibility as a differential diagnosis of the right adnexal mass in a patient without previous appendectomy.  相似文献   
35.
Summary Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferaton. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease.  相似文献   
36.
Sex, age and 21 routine liver function assays were analyzed by stepwise selection and the best-of-all-possible-combinations method to identify a small group of assays valuable in establishing which liver cirrhosis (LC) patients have a high risk of hepatocellular carcinoma (HCC), when alpha-fetoprotein (AFP) is not elevated. Data was obtained from 115 HCC and 122 LC patients on admission. Tumor size correlated with AFP (0.73), alkaline phosphatase (ALP, 0.47), leucine aminopeptidase (LAP, 0.42), lactic dehydrogenase (LDH, 0.42), and the glutamic oxaloacetic transaminase (GOT)/glutamic pyruvic transaminase (GPT) ratio (GOT/GPT, 0.41). The mean of the correct diagnosis rates (CDR) of HCC and LC utilizing AFP as the sole parameter (89%) was markedly higher than those of the other parameters. The best-of-all-possible-combinations method presented a more powerful combination than stepwise selection. The best combination of 7 parameters (LAP, GOT/GPT, choline esterase, one-hour erythrocyte sedimentation rate, age, albumin/globulin ratio, and total bilirubin) presented a mean CDR of 80%, HCC CDR of 77%, and false positive rate of 18%. LC patients statistically diagnosed as having HCC by these 7 parameters are proposed as high risk patients. Fourteen (78%) of 18 HCC patients who were AFP-negative were statistically diagnosed. This analysis can be applied to LC patients to distinguish those that should be followed closely by imaging diagnostic techniques.  相似文献   
37.
Destruction of the inferior olivary nucleus was performed in newborn kittens in order to study the role of climbing fibers in the postnatal development of the cerebellum. In the three kittens which survived for 40–45 days after the unilateral destruction at 2 days old, histological examination demonstrated the lack of dendritic arborization in many Purkinje cells in the cerebellar cortex contralateral to the lesion. The olivectomized kittens showed cerebellar symptoms which became conspicous when the kittens started to walk. The results reveal an important role of climbing fibers in the development of Purkinje cell dendrites.  相似文献   
38.
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer.  相似文献   
39.
Primary sclerosing cholangitis (PSC) is known to be frequently associated with inflammatory bowel diseases. In a rat with self-filling blind loop (SFBL), a proposed animal model for PSC, hepatobiliary inflammation has previously been demonstrated. In this study, we assessed the involvement of lipopolysaccharide (LPS), a bacterial endotoxin, in the pathogenesis of hepatobiliary inflammation of the SFBL model. The hepatic localization of LPS was examined by immunohistochemistry using an anti-lipid A antibody. The portal blood concentration of LPS was measured by an endotoxin-specific chromogenic Limulus test (Endospecy test). LPS was localized in the biliary epithelial cells (BECs) of rats with SFBL, and the portal blood concentration of LPS was significantly higher than that of sham-operated rats. Development of hepatobiliary inflammation, peribiliary fibrosis, and injury to the intestinal mucosa were histologically confirmed. Constriction in the biliary trees was radiologically demonstrated. These findings suggested that abnormal accumulation of LPS, which may be derived from portal blood, in BECs was involved in the pathogenesis of hepatobiliary inflammation with intestinal injury.  相似文献   
40.
A multi-center study on seasonal affective disorder (SAD) was conducted from the autumn of 1988 to the spring of 1989 with the cooperation of 16 facilities in Japan. Forty-six SAD patients were identified among 1104 respondents to our advertisements in mass media, or patients seen at the outpatient clinics. Essentially similar findings to other previous reports were obtained in terms of onset age of the first episode, duration of episode, high proportion of depression in first-degree relatives and atypical vegetative symptoms. However, a nearly equal sex ratio, together with a high proportion of unipolar depression, is characteristic of the present study. Increased appetite and carbohydrate craving were predominant only in female patients, whereas hypersomnia was prominent in both sexes. Effective response to light therapy was found in 17 SAD patients. However, a controlled study on a large number of patients is required to allow final conclusions on the efficacy of light therapy in Japanese SAD patients.  相似文献   
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