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131.
Safer-sex guidelines established during the early days of the HIV/AIDS epidemic have undergone very little revision despite some controversy. Although these guidelines have been widely disseminated in the gay community, many gay men continue to engage in behaviors that are believed to put them at high risk for transmission of HIV. This suggests either that they have not accepted safer-sex guidelines as accurate or that other factors override personal implementation of the guidelines. The study examined seronegative gay men's beliefs about the accuracy of safer sex guidelines and the men's participation in behaviors risky for transmitting HIV. The greatest disagreement between the men's beliefs and behaviors centered on the risk of oral intercourse; this suggests a need for clarification of the safer sex message about this behavior. The findings of this study support the need to reformulate safer-sex guidelines. When unprotected oral and anal sex are classified at the same level of risk, those who engage in unprotected oral sex may proceed to unprotected anal sex with less reservation. 相似文献
132.
S Albrecht JC Goodman S Rajagopolan M Levy DA Cech LD Cooley 《Canadian Metallurgical Quarterly》1994,81(3):466-471
Gorlin's syndrome, also known as multiple basal cell carcinoma syndrome, is a familial tumor condition with autosomal-dominant inheritance. Patients develop multiple basal cell carcinomas beginning in childhood. They also have a typical dysmorphic facies, skeletal malformations, and a particular type of epithelial cyst of the jaws. Recent evidence localizes a Gorlin's syndrome locus on chromosome 9 at band q31. Both tumors and malformations of the central nervous system occur with Gorlin's syndrome. Medulloblastoma is the primary brain tumor most frequently associated with this syndrome; over 40 such cases have been reported. However, only seven cases of meningioma associated with Gorlin's syndrome have been described. The authors report the case of a woman with Gorlin's syndrome whose mother and maternal grandfather also had the condition. The patient was found to have a medulloblastoma at 4 years of age and presented with a large bifrontal meningioma at 19 years of age. The meningioma was histologically malignant and had a complex karyotype with multiple translocations including a t(5;9) with the breakpoint on chromosome 9 located at 9q32. The constitutional karyotype of the mother was normal. No mutations of exons 5 to 9 of the p53 gene were detected using single-stranded conformational polymorphism analysis. 相似文献
133.
VI Turilova TD Smirnova MP Samo?lovich TR Sukhikh 《Canadian Metallurgical Quarterly》1998,40(6):536-548
The morphology and Ag-staining of nucleoli in human multiple myeloma cell lines RPMI 8226 and U 266, distinguished from each other in the differentiation degree, were quantitatively studied, and the production of immunoglobulins or their fragments by the line cells was evaluated throughout 7 days after cell seeding. The less differentiated cell line RPMI 8226 and the high differentiated cell line U 266 were revealed to differ in both the initial level of immunoglobulin production and dynamics of immunoglobulin accumulation in culture medium. The total number of Ag-stained nucleolar-organizer regions (AgNORs) per nucleus in cells RPMI 8226 was significantly higher than in cells U 266 in all times after seeding of the cells. In both cell lines changes in the quantity and shape of nucleoli and also in the total number of AgNORs per nucleus and pattern of AgNORs distribution within nucleoli correlated with the cell cycle phase. Relationships between morphofunctional changes in nucleoli and the differentiation degree and proliferative activity of the cells, and also between the number of Ag-positive nucleolar-organizing metaphase chromosomes and the functional activity of interphase AgNORs are discussed. 相似文献
134.
IE van der Horst-Bruinsma JM Hazes GM Schreuder TR Radstake P Barrera LB van de Putte D Mustamu D van Schaardenburg FC Breedveld RR de Vries 《Canadian Metallurgical Quarterly》1998,57(11):672-675
OBJECTIVE: It has recently been observed that non-inherited maternal DR4 antigens (NIMAs) of DR4 negative rheumatoid arthritis (RA) patients were increased compared with non-inherited paternal DR4 antigens (NIPAs). The aim of this study was to determine the prevalence of non-inherited DR4 antigens and DRB1 alleles in parents of RA patients. METHODS: HLA-DR serology and DRB1 typing was performed in 97 RA patients and their parents. NIMA and NIPA frequencies were compared, stratified according to the presence of DR4 and/or the shared epitope (SE). RESULTS: In DR4 negative patients, NIMA DR4 was increased compared with NIPA DR4 (OR 3.10, 95% CI 0.76, 12.70). When combined with results from a previous study this increase was significant (OR 3.65, 95% CI 1.29, 10.31). The NIMA effect of SE positive DR4 subtypes in this study (OR 4.73, 95% CI 0.94, 23.8) was stronger than the NIMA effect of combined SE positive DRB1 alleles (OR 2.19 95% CI 0.36, 13.22). CONCLUSIONS: The association between non-inherited maternal HLA-DR4 alleles and the susceptibility to RA was observed in two independent populations. 相似文献
135.
D Ford DF Easton M Stratton S Narod D Goldgar P Devilee DT Bishop B Weber G Lenoir J Chang-Claude H Sobol MD Teare J Struewing A Arason S Scherneck J Peto TR Rebbeck P Tonin S Neuhausen R Barkardottir J Eyfjord H Lynch BA Ponder SA Gayther M Zelada-Hedman 《Canadian Metallurgical Quarterly》1998,62(3):676-689
The contribution of BRCA1 and BRCA2 to inherited breast cancer was assessed by linkage and mutation analysis in 237 families, each with at least four cases of breast cancer, collected by the Breast Cancer Linkage Consortium. Families were included without regard to the occurrence of ovarian or other cancers. Overall, disease was linked to BRCA1 in an estimated 52% of families, to BRCA2 in 32% of families, and to neither gene in 16% (95% confidence interval [CI] 6%-28%), suggesting other predisposition genes. The majority (81%) of the breast-ovarian cancer families were due to BRCA1, with most others (14%) due to BRCA2. Conversely, the majority of families with male and female breast cancer were due to BRCA2 (76%). The largest proportion (67%) of families due to other genes was found in families with four or five cases of female breast cancer only. These estimates were not substantially affected either by changing the assumed penetrance model for BRCA1 or by including or excluding BRCA1 mutation data. Among those families with disease due to BRCA1 that were tested by one of the standard screening methods, mutations were detected in the coding sequence or splice sites in an estimated 63% (95% CI 51%-77%). The estimated sensitivity was identical for direct sequencing and other techniques. The penetrance of BRCA2 was estimated by maximizing the LOD score in BRCA2-mutation families, over all possible penetrance functions. The estimated cumulative risk of breast cancer reached 28% (95% CI 9%-44%) by age 50 years and 84% (95% CI 43%-95%) by age 70 years. The corresponding ovarian cancer risks were 0.4% (95% CI 0%-1%) by age 50 years and 27% (95% CI 0%-47%) by age 70 years. The lifetime risk of breast cancer appears similar to the risk in BRCA1 carriers, but there was some suggestion of a lower risk in BRCA2 carriers <50 years of age. 相似文献
136.
137.
In this case report we describe the coincidental finding of polyps in the gallbladder by ultrasound investigation in a six-year-old girl, known to have metachromatic leukodystrophy. The investigation was carried out because of suspicion of abdominal trauma after falling down the stairs and finding elevated serum amylase. 相似文献
138.
The study aimed to evaluate the perception of discrimination in the Czech national HIV policy among gay men. The anonymous questionnaires were published in the gay journal and 191 respondents filled them and returned back. Their assessment of discrimination in the HIV policy and other life activities were ranked in 5-points scale. Assumed discrimination in the HIV policy was found to be one of the lowest one. Forty-one percent of men who answered did not find any discrimination in the HIV policy at all, eleven percent of them perceived it at the highest level. The personal perception of HIV discrimination was related to the fear of discrimination in the health facilities and to the general evaluation of political change for gay life. HIV policy is generally viewed as tolerant and without discriminative approach toward vulnerable minorities. The number of negative evaluations can play important role in the obstacles of preventive programs. 相似文献
139.
PURPOSE: Extracorporeal membrane oxygenation (ECMO) is an accepted therapy for neonatal pulmonary failure, but its use in older children has been controversial. METHODS: Over 13 years, 55 children (ages, 3 months to 16 years) were treated with venoarterial or venovenous ECMO. The diagnoses were viral, bacterial, or fungal pneumonia (24 patients); hydrocarbon or gastric aspiration (n = 10); adult respiratory distress syndrome (ARDS), sepsis, near drowning (n = 15); pulmonary contusion (n = 2); airway obstruction (n = 3); pulmonary artery foreign body (n = 1). Pre-ECMO blood gas ranges (and means) were PO2, 21 to 100 (n = 44); PCO2, 23 to 125 (n = 72); pH, 6.81 to 7.55 (n = 7.11). RESULTS: All patients received inotropes, and 38 required dialysis or hemofiltration. ECMO was used for 20 to 613 hours (mean, 196 hours). Patient complications included cannulation site hemorrhage (n = 40), renal failure (n = 10), seizures (n = 8), stroke (n = 3), and cerebral hemorrhage (n = 2). Twenty-five patients (45%) survived ECMO, with 21 long-term survivors (10 pneumonia, five aspiration, five ARDS, one pulmonary contusion), five of whom have mild to moderate neurological deficit. Patients with combinations of pulmonary, cardiac, and renal failure, or sepsis did not survive. CONCLUSIONS: ECMO is an invasive technique that can be life saving in the child with isolated respiratory failure, but its usefulness in children with multiorgan failure is less certain. 相似文献
140.
SV Kuruttukulam S Krishnaswami ST Chandy TR Muralidharan 《Canadian Metallurgical Quarterly》1995,47(5):477-480
Seventy two consecutive patients without a history of diabetes and normal fasting plasma glucose were included in this study of insulin levels. Standard oral glucose tolerance test with 75 gm glucose and fasting and two hour insulin levels were estimated in all patients. Coronary artery disease (CAD) was confirmed or excluded by selective coronary arteriography. In 20 patients, CAD was diagnosed by electrocardiographic (ECG) and clinical evidence of earlier myocardial infarction. Mean fasting plasma insulin was 31.40 +/- 22.2 IU/dl in the CAD positive and 32.3 +/- 13.6 IU/dl in the CAD negative group. The mean two hour plasma insulin was 274.6 +/- 301.1 IU/dl in the CAD positive and 104.8 +/- 74.9 IU/dl in the CAD negative group (p < 0.04). Two hour plasma insulin levels were significantly higher in patients with atherosclerotic coronary artery disease. It is concluded that the estimation of a two hour plasma insulin level after 75 gm of glucose load, could help differentiate CAD from normals. 相似文献