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91.
Lynn R. Sorbara Zhichun Tang Alessandro Cama Jinru Xia Esther Schenker Ronald A. Kohanski Leonid Poretsky Elizabeth Koller Simeon I. Taylor Andrea Dunaif 《Metabolism: clinical and experimental》1994,43(12)
Women with polycystic ovary syndrome (PCOS) are markedly insulin-resistant, but the molecular mechanisms of these changes and their relationship to the hyperandrogenic state remain to be clarified. Mutations have recently been identified in the insulin receptor gene of patients with extreme forms of insulin resistance associated with hyperandrogenism (eg, type A insulin resistance), and these mutations account for the insulin resistance in such patients. We performed this study to determine whether mutations in the coding portion of the insulin receptor gene were responsible for insulin resistance in PCOS. Insulin binding studies using cultured skin fibroblasts of three obese (body mass index > 27 kg/m2) women with PCOS (ie, mild hyperandrogenemia and chronic anovulation of unknown etiology) and documented insulin resistance showed no apprarent abnormalities in either the number or affinity of insulin binding sites. Direct sequencing of all 22 exons of the insulin receptor gene from two of the women with PCOS did not reveal any mutations. Furthermore, both alleles of the gene were expressed at equal levels. In a third insulin-resistant PCOS woman, there was no evidence for a mutation in the coding portion of the insulin receptor gene as determined by denaturing gradient gel electrophoresis (DGGE). We conclude that the insulin resistance in these PCOS women was caused by a defect extrinsic to the insulin receptor. 相似文献
92.
Andrea Veltri Simona Capello Barbara Faissola Francesco Spalluto Sergio Farinet Maurizio Grosso 《Cardiovascular and interventional radiology》1994,17(3):133-137
Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO2 through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO2 allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation. 相似文献
93.
Mono- and bi-allelic expression of insulin-like growth factor II gene in human muscle tumors 总被引:4,自引:1,他引:3
Pedone Paolo V.; Tirabosco Roberto; Cavazzana Andrea O.; Ungaro Paola; Basso Giuseppe; Luksch Roberto; Carli Modesto; Bruni Carmelo B.; Frunzio Rodolfo; Riccio Andrea 《Human molecular genetics》1994,3(7):1117-1121
Insulin-like growth factor II (IGF-II) is a mitogen for manycell types and an important modulator of muscle growth and differentiation.IGF-II gene is prevalently expressed during prenatal developmentand its gene activity is regulated by genomic imprinting, inthat the allele inherited from the father is active and theallele inherited from the mother is inactive in most normaltissues. IGF-II expression is activated in several types ofhuman neoplasms and an alteration of IGF-II imprinting has beendescribed in BeckwithWiedemann syndrome and Wilms' tumour.Here we show that monoallelic expression of IGF-II gene is conservedin normal adult muscle tissue whereas two or more copies ofactive IGF-II alleles, arising by either relaxation of imprintingor duplication of the active allele, are found in 9 out of 11(82%) rhabdomyo-sarcomas retaining heterozygosity at 11p15,regardless of the histological subtype. Since IGF-II has beenindicated as an autocrine growth factor for rhabdomyosarcomacells, these findings strongly suggest that acquisition of adouble dosage of active IGF-II gene is an important step forthe initiation or progression of rhabdomyosarcoma tumorigenesis.Among different types of muscle tumors, relaxation of imprintingseems to arise prevalently in rhabdomyosarcomas, since we havedetected only one case of partial reactivation of the maternalIGF-II allele out of 7 lelomyosarcomas tested. 相似文献
94.
Thomas M. Gehring PhD Daniel Marti MS MD Andrea Sidler MA 《Child psychiatry and human development》1994,25(2):125-138
Perceptions of family cohesion and hierarchy structures were assessed by theFamily System Test (FAST), a clinically-derived figure placement technique. Parents (N=140) and their preadolescent offspring (N=70) completed typical and conflict representations in individual as well as group settings. Typical representations were characterized by balanced family structures (i.e. cohesive and moderately hierarchical) and those displaying conflict situations showed predominantly unbalanced patterns. FAST portrayals were related to respondent (mother vs. father vs. child). Fathers represented typical family relations as balanced more often than mothers. Regarding conflict representations, children were more likely than fathers to portray the family as unbalanced. However, analyses of representations of the same family (i.e. intra-family comparisons) indicated that all respondents differed in their perceptions and, that fathers' typical portrayals showed most often the same structure as those done by the family members as a group. 相似文献
95.
Andrea J Fradkin Peter A Cameron Belinda J Gabbe 《Journal of Science and Medicine in Sport》2007,10(1):66-71
Golfing injuries have been shown to occur frequently, and injury countermeasures have been suggested to help reduce injury risk. Performing an appropriate warm-up is thought to reduce injury risk, however there is a lack of evidence to support this notion. Therefore this study aimed to investigate the relationships between warm-up participation and injury in a cohort of female golfers. A total of 522 golfers participating in the Victorian Women's Pennant Competition completed the study. Over one-third (35.2%) of the golfers reported having sustained a golfing injury within the previous 12 months, with the lower back the most commonly injured region. Most golfers reported not warming-up prior to play or practice. Golfers who reported not warming-up on a regular basis were more likely to have reported a golfing injury in the previous 12 months than those reporting frequent warm-up participation (OR=45.2; 95% CI: 13.5, 151.7). Less skilled golfers were also less likely to report sustaining a golfing injury than more skilled golfers (OR=0.2; 95% CI: 0.1, 0.5). This study is one of the few to establish an association between warm-up participation and injury. Further prospective studies are warranted to determine whether warm-up reduces injury risk for golf participation. 相似文献
96.
97.
Angelo Pan Placido Mondello Klara Posfay-Barbe Patrizia Catenazzi Annise Grandi Silvia Lorenzotti Andrea Patroni Nadia Poli Laura Soavi Giuseppe Carnevale 《Infection control and hospital epidemiology》2007,28(9):1099-1102
In an Italian hospital, we observed that hand hygiene was performed in 638 (19.6%) of 3,253 opportunities, whereas gloves were worn in 538 (44.2%) 1,218 of opportunities. We observed an inverse correlation between the intensity of care and the rate of hand hygiene compliance (R2=0.057; P<.001), but no such association was observed for the rate of glove use compliance (R2=0.014; P=.078). Rates of compliance with hand hygiene and glove use recommendations follow different behavioral patterns. 相似文献
98.
Identification of the C-terminal flanking peptide of preprocholecystokinin in rat brain by a novel radioimmunoassay 总被引:1,自引:0,他引:1
The C-terminal flanking peptide of preprocholecystokinin (preproCCK) has been identified in extracts of rat brain using a novel radioimmunoassay. There is a single form of immunoreactive material on gel filtration, ion exchange and reversed-phase HPLC. The C-terminal preproCCK immunoreactivity had a similar pattern of distribution to CCK8 in different regions of rat brain. This assay should help in studies of neuronal CCK biosynthesis. 相似文献
99.
Andrea Frudinger Research Registrar Clive I. Bartram Consultant John A. D. Spencer Consultant Michael A. Kamm Consultant 《BJOG : an international journal of obstetrics and gynaecology》1997,104(9):1009-1013
Objective To assess the relation between perineal inspection and sphincter integrity in parous women.
Design Prospective observational study.
Setting District general hospital.
Population Fifty-seven consecutive parous women attending a gynaecology clinic for problems unrelated to the pelvic floor.
Methods A detailed history of bowel function and mode of delivery obtained; the perineum inspected to determine the presence and position of scarring, and anal endosonography performed.
Results In 19 women with an intact perineum on inspection, endosonography showed perineal scarring in five, with both perineal and sphincter scarring in three. Four had urge faecal incontinence. Three patients had a perineal tear only on inspection, but this group was too small for analysis and was discounted. Nine had an episiotomy scar only. Endosonography demonstrated perineal scarring in four, and combined perineal and sphincter scarring in two; one woman in this group had urge faecal incontinence. Twenty-six women had episiotomy and perineal tears on inspection. Endosonography revealed underlying perineal scarring in five women, with combined perineal and sphincter scarring in 14; six women in this group had urge faecal incontinence and one passive incontinence for flatus. Sonographically the scarring was anterior and circumferential rather than radial, and mostly left-sided, whereas on inspection episiotomy and perineal scarring were right sided.
Conclusions A normal perineum on clinical examination does not exclude underlying sphincter damage. The incidence of sphincter damage increases significantly when an episiotomy scar is associated with a perineal tear. 相似文献
Design Prospective observational study.
Setting District general hospital.
Population Fifty-seven consecutive parous women attending a gynaecology clinic for problems unrelated to the pelvic floor.
Methods A detailed history of bowel function and mode of delivery obtained; the perineum inspected to determine the presence and position of scarring, and anal endosonography performed.
Results In 19 women with an intact perineum on inspection, endosonography showed perineal scarring in five, with both perineal and sphincter scarring in three. Four had urge faecal incontinence. Three patients had a perineal tear only on inspection, but this group was too small for analysis and was discounted. Nine had an episiotomy scar only. Endosonography demonstrated perineal scarring in four, and combined perineal and sphincter scarring in two; one woman in this group had urge faecal incontinence. Twenty-six women had episiotomy and perineal tears on inspection. Endosonography revealed underlying perineal scarring in five women, with combined perineal and sphincter scarring in 14; six women in this group had urge faecal incontinence and one passive incontinence for flatus. Sonographically the scarring was anterior and circumferential rather than radial, and mostly left-sided, whereas on inspection episiotomy and perineal scarring were right sided.
Conclusions A normal perineum on clinical examination does not exclude underlying sphincter damage. The incidence of sphincter damage increases significantly when an episiotomy scar is associated with a perineal tear. 相似文献
100.
Data on the prevalence of antibody to hepatitis C virus among 278 subjects in an institution for the mentally handicapped were analysed by risk factors. A prevalence of 4% was found, higher than blood donors belonging to the same area (1.4%). No differences in prevalence with regard the length of residence, age, sex, degree of retardation or for presence of HBV markers were observed. 相似文献