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51.
Eighteen Coopworth ewe lambs were divided into three groups based on the initial cystourethrogram and cystometry findings at 5-7 weeks of age: group 1, 6 lambs with spontaneous low-pressure bilateral vesicoureteric reflux (VUR) on bladder filling were used to study the natural history of reflux; group 2, 5 lambs with no VUR detected were used to establish an experimental model of bilateral VUR using an unroofing surgical procedure; group 3, 7 lambs with spontaneous VUR detected during micturition had the same surgical procedure to increase the degree of VUR. All three animal groups were followed for 4-10 months. Spontaneous VUR was demonstrated in 13 of 18 lambs (25/36 ureters). The presence and severity of spontaneously occurring reflux in group 1 lambs diminished with increasing age. VUR was created successfully in group 2 and increased in degree in group 3 animals. The only significant histological finding in all three animal groups with grades II and III VUR was distal renal tubular dilatation. The sheep is a useful and readily available animal for studying VUR. During 4-10 months of follow-up, sterile reflux without bladder outflow obstruction resulted in distal renal tubular dilatation, but no renal parenchymal damage. 相似文献
52.
Tsang-Tse Fang Huey-Lin Hsieh Fuh-Shan Shiau 《Journal of the American Ceramic Society》1993,76(5):1205-1211
The effects of pore morphology and grain size on the dielectric behavior of high-purity stoichiometric BaTiO3 have been intensively investigated. It was found that the dielectric constant was influenced not only by grain size but also by pore morphology. Dielectric constants below the Curie temperature could be evaluated by the Maxwell relationship for specimens with fractional density >90%ρt and be estimated by the modified Niesel's equation, but depolarization might be involved for specimens with fractional density <90%ρt . Dielectric Behavior above the Curie temperature followed the Curie–Weiss low. The Curie constants could be separated into two regions depending on the pore morphology, decreasing linearly with increasing porosity at different rates. The results suggest that the tetragonal–cubic phase transition temperature of specimens with fractional density <90%ρt is affected by depolarization due to the presence of continous channel pores. The dissipation factor was increased with increasing porosity due to the adsorption of water. In this study, a high-density (<99%ρt ), uniform, and fine-grained (∼1.2 μm) microstructure of high-purity stoichimetric barium titanate has been produced by using wet processing ad pressureless sintering, in which a high dielectric constant (>6100 at 25°C and 1 kHz) and a low dissipation factor (<0.025) could be achieved. 相似文献
53.
Stimulatory effects of several types of adjuvants on secondary antibody response to inactivated Newcastle disease virus (iNDV) were examined in chickens. For this purpose, animals were primed with iNDV without adjuvant resulting in a low but significant antibody response, boosted with iNDV plus adjuvant 3 weeks later, and analysed for specific antibody titres in serum 3 weeks after the booster. Water-in-mineral oil emulsion (W/O) caused significant increase in antibody titres measured in an indirect enzyme-linked immunosorbent (ELISA), haemagglutination inhibition (HI), and virus neutralisation (VN) assay. The adjuvants tested included three oil-in-water emulsions (i.e. mineral oil-in-water, sulpholipo(SL)-Ficoll400/squalane-in-water and sulpholipo-cyclodextrin/squalane-in-water), three negatively-charged polymers with high molecular weight (i.e. polyacrylate, polystyrenesulphonate and sulpho(S)-Ficoll400) and two surface-active agents (i.e. dimethyldioctadecylammonium bromide (DDA) and Quil A). These adjuvants enhanced significantly the secondary immune response but none reached the titre obtained with W/O. Combinations of adjuvants with distinct physicochemical properties, i.e. polyacrylate and DDA revealed only slight, beneficial effects. We concluded that the various types of adjuvants tested can stimulate secondary immune responses in primed animals but that W/O is superior. 相似文献
54.
TS Yeh YY Jan LB Jeng TC Chen TL Hwang MF Chen 《Canadian Metallurgical Quarterly》1998,26(5):1224-1226
We performed a 17-year retrospective analysis of 10 cases of hepatocellular carcinoma presenting as pyogenic liver abscess. Spontaneous tumor necrosis and biliary obstruction caused by tumor thrombi, superimposed with bacterial infection, were the two major pathogeneses. Exact diagnosis of the underlying hepatocellular carcinoma was made for five of the 10 patients before management was attempted. Main clinical manifestations included fever, chills, right-upper-quadrant pain, malaise, anorexia, jaundice, and hepatomegaly. Characteristics such as middle age and male sex, seropositivity for hepatitis B and/or hepatitis C, chronic liver disease, unexplained anemia, marked weight loss, and a severely inversed albumin/globulin ratio raise suspicions about the underlying hepatocellular carcinoma. Management strategies included percutaneous drainage (n = 3), surgical drainage (n = 4), and hepatectomy (n = 3) in addition to administration of parenteral antibiotics in all cases. The prognosis was dismal, with a mean survival of 3.5 months (range, 8 days to 6 months). 相似文献
55.
YY Chiang KF Tseng YW Lih TC Tsai CT Liu HK Leung 《Canadian Metallurgical Quarterly》1996,34(4):243-246
One hundred and twenty-six cases of cerebellopontine angle tumors with various histologies are presented. Results of 75 operated vestibular neurinomas, 22 meningiomas, and 16 tumors with other histologies are discussed. The method of irradiation and non-radical surgery may be an alternative for treatment. 相似文献
56.
SH Cho JY Seo DC Choi HJ Yoon YJ Cho KU Min GK Lee JW Seo YY Kim 《Canadian Metallurgical Quarterly》1996,26(10):1210-1219
BACKGROUND: There have been many studies concerning pathological changes in bronchial mucosa from asthmatics; however, few studies has been carried out to evaluate pathological changes according to the severity of asthma. OBJECTIVE: This study was designed to evaluate the cellular components in bronchoalveolar lavage fluid (BALF) and histological abnormalities in asthmatics according to the severity of asthma. METHODS: Bronchoalveolar lavages, bronchoscopic biopsies and ultrastructural examinations were performed in 13 asthmatics and 11 (BAL) or four (biopsies) non-asthmatic controls. The proportions of epithelial cells and correlations with PC20Meth which reflects bronchial hyperresponsiveness. Light microscopic examination revealed loss of epithelium, inflammatory cell infiltrations and thickening of the basement membrane which also showed significant correlation with PC20Meth. Hypertrophy of airway smooth muscles and hyperplasia of mucous glands were prominent in asthmatics but there was no difference according to the severity of asthma. Ultrastructural examination revealed that basement membrane thickening on light microscopic examination is due to the increased subepithelial collagen deposition with normal thickness of basal lamina. CONCLUSION: These data suggest that loss of epithelial cells, infiltration of inflammatory cells, especially eosinophils, and increased deposition of subepithelial collagen play major roles in determining the severity of asthma and non-specific bronchial hyperresponsiveness. 相似文献
57.
CC Chang FJ Tsai HD Tsai CH Tsai YY Hseih CC Lee TC Yang JY Wu 《Canadian Metallurgical Quarterly》1998,18(6):621-625
Apert syndrome (AS) is clinically characterized by typical facial features and symmetrical syndactyly of the digits. AS is inherited as an autosomal dominant trait. Recently, a fibroblast growth factor receptors 2 (FGFR2) mutation, either C934G or C937G, was identified in exon IIIa. Our report documents an affected mother and son in whom one of the two mutations in AS had occurred sporadically in the mother. The diagnosed of AS was based on associated abnormal physical features and on molecular genetic analysis. A C-to-G transversion at position 937 of the cDNA resulting in a proline-to-arginine substitution at codon 259 was found in the mother. In her second pregnancy, prenatal diagnosis by both restriction analysis and direct sequencing was undertaken and this showed that the female fetus had not inherited the mutation. 相似文献
58.
HK Shu PK Sneed CY Shiau MW McDermott KR Lamborn E Park M Ho PL Petti V Smith LJ Verhey WM Wara PH Gutin DA Larson 《Canadian Metallurgical Quarterly》1996,2(6):335-342
BACKGROUND: Significant changes are restructurng the U.S. health care delivery system. National health reform is now extending itself into the public sector. Increased health and medical costs by federal and state governments are forcing a reevaluation of major entitlement programs, especially Medicaid. METHODS/RESULTS: Because Medicaid is the single largest item in many state budgets, states are now enrolling Medicaid patients into managed and coordinated care arrangements as a means to control costs and increase access to care. HMOs are not only competing for private patients but also actively seeking the Medicaid population. Nationally, almost one-fourth of all Medicaid patients are now enrolled in managed care plans. Various models and approaches have been developed by individual states. CONCLUSIONS: Because managed care enrollment in the Medicaid program has increased substantially in recent years, selected services including vision care are no longer rendered by any practitioner willing to accept Medicaid fees. Freedom of choice is now restricted to pre-selected and panel practitioners participating with the managed care program. The rules, regulations, billing procedures, fees, and program requisites will differ under managed care programs. Private optometric practitioners must consider entering economic and organizational relationships and linkages that make them attractive to managed care organizations. 相似文献
59.
The effects of midazolam (MID) on the in vitro growth and differentiation of two murine myeloid leukemia WEHI 3B (JCS) and M1 cells were studied. MID inhibits the proliferation of both M1 and JCS cells in a dose-dependent manner. At the concentration of 10 micrograms/ml, MID was found to induce both monocytic and granulocytic differentiation of the JCS but not M1 cells. Induction of morphological differentiation of the JCS cells was also associated with the enhanced expression of the differentiation antigens Mac-1, F4/80, and Gr-1 for the cells. Results from mRNA phenotyping experiments also indicated that the expression of tumor necrosis factor (TNF-alpha) and neutrophil-specific J11d differentiation marker was significantly upregulated in MID-treated JCS cells. In addition, the phagocytic activity of MID-treated JCS cells was increased towards opsonized yeast cells. Results from this investigation suggested that MID may be used as an inducer for further study on the mechanisms of differentiation in these myeloid leukemia cells. 相似文献
60.
Vascular MADs: two novel MAD-related genes selectively inducible by flow in human vascular endothelium 总被引:2,自引:0,他引:2
JN Topper J Cai Y Qiu KR Anderson YY Xu JD Deeds R Feeley CJ Gimeno EA Woolf O Tayber GG Mays BA Sampson FJ Schoen MA Gimbrone D Falb 《Canadian Metallurgical Quarterly》1997,94(17):9314-9319
Vascular endothelium is an important transducer and integrator of both humoral and biomechanical stimuli within the cardiovascular system. Utilizing a differential display approach, we have identified two genes, Smad6 and Smad7, encoding members of the MAD-related family of molecules, selectively induced in cultured human vascular endothelial cells by steady laminar shear stress, a physiologic fluid mechanical stimulus. MAD-related proteins are a recently identified family of intracellular proteins that are thought to be essential components in the signaling pathways of the serine/threonine kinase receptors of the transforming growth factor beta superfamily. Smad6 and Smad7 possess unique structural features (compared with previously described MADs), and they can physically interact with each other, and, in the case of Smad6, with other known human MAD species, in endothelial cells. Transient expression of Smad6 or Smad7 in vascular endothelial cells inhibits the activation of a transfected reporter gene in response to both TGF-beta and fluid mechanical stimulation. Both Smad6 and Smad7 exhibit a selective pattern of expression in human vascular endothelium in vivo as detected by immunohistochemistry and in situ hybridization. Thus, Smad6 and Smad7 constitute a novel class of MAD-related proteins, termed vascular MADs, that are induced by fluid mechanical forces and can modulate gene expression in response to both humoral and biomechanical stimulation in vascular endothelium. 相似文献