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Correlation between penile angiography and duplex scanning of cavernous arteries in impotent men 总被引:1,自引:0,他引:1
During the diagnostic evaluation of patients with vasculogenic impotence duplex scanning has been proposed as a reliable noninvasive method to evaluate the cavernous arteries. However, the sensitivity and specificity of this test have never been elucidated. To provide insight into the clinical value of this test 25 men who presented with impotence and failed to respond to 60 mg. intracavernous papaverine were evaluated with duplex scanning and the results of this modality were compared to penile angiography. The cavernous arteries were considered normal by duplex scanning if the artery demonstrated either a 60% or greater increase in diameter and/or a peak flow velocity of greater than 25 cm. per second 5 minutes after papaverine injection. Penile angiography was considered normal if both cavernous arteries were visualized and appeared to be normal radiographically (after intracorporeal papaverine). In the 25 patients studied there was no significant difference in peak flow velocity between patients with normal or abnormal cavernous arteries by angiography. In addition, arterial dilatation (more than 60%) after papaverine injection did not correlate with the results of the angiogram. These data demonstrate that duplex scanning of the cavernous arteries does not correlate well with what is observed by penile angiography in a selected population of men with vasculogenic erectile dysfunction. Since penile angiography itself has limitations in the evaluation of the penile arteries, the reliability of duplex scanning to identify cavernous artery dysfunction needs additional confirmation. 相似文献
3.
Esinduy Canan B.; Chang Chia Cheng; Trosko James E.; Ruch Randall J. 《Carcinogenesis》1995,16(4):915-921
We examined whether the inhibition of neoplastically transformedcell growth by co-cultured non-transformed cells involved gapjunctional intercellular communication (GJIC). The growth ofpoorly communicating ( 相似文献
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Korkusuz P Ugur Y Aşan E Aktuna Keskil Z Uluoglu C 《Okajimas folia anatomica Japonica》2002,79(2-3):83-92
Probucol is a lipid-lowering agent with an antioxidant effect; however, its influence on the liver remains unclear. The effects of probucol on hyperlipidemic rabbit liver are investigated to add a structural data on its therapeutical profile. Local albino rabbits were divided into three groups. 1) Hyperlipidemic group: fed with 1% cholesterol (150 g/kg/day) enriched chow for 2 months. 2) Probucol treated group: group 1 + intraperitoneal probucol (10 mg/kg/day) administration for 15 days. 3) Control group fed with normal chow. The blood lipid profile was investigated biochemically. Liver samples were examined electronmicroscopically. Within the parenchymal cells of group 1, the amount of rough surfaced endoplasmic reticulum was increased, its cisterna was dilated displaying a moderately electron dense substance in it and showed close apposition with the condensed mitochondria. In group 2, smooth surfaced endoplasmic reticulum was in extensive amounts filling almost all of the cytoplasm, displayed a reticular, degenerated appearance and was in close relation with the condensed, degenerated mitochondria. Probucol may cause degenerative changes on the liver parenchyme at the subcellular level. It alters the structure of these cells mainly acting on the smooth surfaced endoplasmic reticulum and the mitochondria that are known to be involved in cellular detoxification. 相似文献
6.
Tekin M Kavaz A Berberoğlu M Fitoz S Ekim M Ocal G Akar N 《American journal of medical genetics. Part A》2004,(3):284-287
We report on a Turkish family in which the father and his two sons were diagnosed as having the KBG syndrome. Large upper central incisors were the diagnostic finding in all three patients along with mental retardation, cryptorchidism, skeletal abnormalities, and short stature. Our report clearly confirms that the inheritance is autosomal dominant in KBG syndrome, although a high male to female ratio has been observed in published cases. 相似文献
7.
Langerhans dendritic cells are antigen presenting cells (APC) that reside within the epidermis and are capable of stimulating naive T cells. Reciprocally, lymphocytes may play a role in Langerhans cells (LC) differentiation. Our results show that the differentiation of skin LC is unaffected in the absence of lymphocytes and/or signaling through the common cytokine receptor gamma chain (gammac) required for IL-2, IL-4, IL-7, IL-9, IL-15 and IL-21 signaling. Migration of LC and other dendritic cells (DC) from the skin to the draining lymph nodes (LNs) after FITC skin sensitization, is unaffected in the absence of lymphocytes or CD40. FITC+ LC/DC sorted from the LNs of lymphoid deficient or control mice stimulated naive T cells with similar efficiency. However, while the absence of lymphocytes did not appear to affect the phenotype or number of emigrating LN DC/LC, their persistence in the LN appears to depend on alphabeta T cells. Thus, DC are strikingly reduced in numbers in the peripheral LNs of T-cell deficient mice. Finally, CD8alpha expression on skin emigrants was low and dependent on the presence of CD8+ lymphocytes, while spleen CD8+ DC were present in the absence of lymphocytes. We conclude that the presence of T cells is not required for the differentiation and migration of resident skin DC but is critical for the maintenance of DC and LC migrating into the LNs. 相似文献
8.
Molecular Characterization of a Full Genome Turkish Hepatitis C Virus 1b Isolate (HCV-TR1): A Predominant Viral Form in Turkey 总被引:1,自引:0,他引:1
Based on direct sequencing information from 5UTR and NS5B regions, we identified subtype 1b as a predominant hepatitis C virus genome in Turkey, which affected more than 91% of 79 patients studied. Next, the full genome sequence of a Turkish 1b isolate was obtained by the cloning of polypeptide-encoding region into 7 overlapping fragments. Turkish 1b isolate, which was named HCV-TR1, comprises 9361 nucleotides, including 306 nucleotides of 5UTR, a single long open reading frame of 9033 nucleotides, and 22 nucleotides of 3UTR. When compared to HCV 1b polypeptide sequences available at GenBank, the predicted polypeptide displayed a total of 36 amino acid substitutions, of which 16 was specific for HCV-TR1 isolate. Despite these changes, major structural and functional motifs of HCV proteins were maintained in HCV-TR1. In contrast, HCV-TR1 displayed amino acid substitutions in 6 out of 9 major cytotoxic T-cell epitopes. These data suggest that HCV-TR1 encodes functionally intact viral proteins, but it also encodes altered viral epitopes, which may affect host immune-response. 相似文献
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10.
Interaction between a peroxisome proliferator-activated receptor gamma gene polymorphism and dietary fat intake in relation to body mass 总被引:5,自引:0,他引:5
Memisoglu A Hu FB Hankinson SE Manson JE De Vivo I Willett WC Hunter DJ 《Human molecular genetics》2003,12(22):2923-2929
The peroxisome proliferator-activated receptor gamma (PPAR gamma) is a critical regulator of adipogenesis. PPAR gamma+/- mice are resistant to high-fat diet-induced obesity and thus PPAR gamma may mediate physiological responses to dietary fat in other mammals. The aim of this study was to determine whether the human PPAR gamma proline to alanine substitution polymorphism (Pro12Ala) modifies the association between dietary fat and adiposity and plasma lipids. Subjects (n=2141) were controls selected for three case-control studies nested within the Nurses' Health Study, a large ongoing prospective cohort study. Associations between intake of total fat, fat subtypes and BMI were different in PPAR gamma 12Ala variant allele-carriers compared with non-carriers. Among homozygous wild-type Pro/Pro individuals, those in the highest quintile of total fat intake, had significantly higher mean body mass index (BMI) compared with those in the lowest quintile (27.3 versus 25.4 kg/m2, respectively; P-trend<0.0001) whereas among 12Ala variant allele-carriers there was no significant trend observed between dietary fat intake and BMI (P-trend=0.99; P-interaction=0.003). In contrast, intake of monounsaturated fat was not associated with BMI among homozygous wild-type women but was inversely associated with BMI among 12Ala variant allele-carriers (mean in lowest quintile=27.6 versus mean in highest quintile=25.5 kg/m2; P-trend=0.006; P-interaction=0.003). The relationship between dietary fat intake and plasma lipid concentrations also differed according to PPAR gamma genotype. These data suggest that PPAR gamma genotype is an important factor in physiological responses to dietary fat in humans. 相似文献