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61.
Human T-lymphotropic virus type III (HTLV-III) contains a gene (tat-III) the product of which activates the expression of viral genes in trans. We have expressed in Escherichia coli the complete tat-III-encoded protein as well as a truncated form that lacks three amino acids from the amino terminus. These proteins are recognized by sera of many, but not all, infected individuals including patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex, as well as asymptomatic seropositive persons. Seropositivity for the tat-III protein does not appear to correlate with the clinical stage of HTLV-III-related disease. Antibodies raised in rabbits against the E. coli-produced protein detect the native protein (apparent molecular mass, 14.5 kDa) in a virus-producing cell line. A second protein (26 kDa), of unknown origin but viral related, is also specifically recognized by the immune serum.  相似文献   
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Background

This study aimed to evaluate fetal echocardiographic measurements at the time of the first fetal echocardiogram as predictors of neonatal outcome for tetralogy of Fallot (TOF).

Methods

The study reviewed all infants with a prenatal diagnosis of TOF from January 2004 to June 2011. Aortic valve (AoV), pulmonary valve (PV), main pulmonary artery (MPA), left and right pulmonary artery diameters, and ductus arteriosus flow were evaluated on fetal echocardiograms, and associations between the fetal echocardiogram and the neonatal echocardiogram measurements and outcomes were assessed.

Results

The study identified 67 TOF patients who had an initial fetal echocardiogram at a mean gestational age of 25.0 ± 5.2 weeks. Patients with absent PV syndrome or major aortopulmonary collaterals were excluded from the study, as were those without anterograde pulmonary blood flow at the first fetal echocardiogram. Of the remaining 44 patients, 10 were ductal dependent and required neonatal surgery. Infants who were ductal dependent had lower fetal PV (?5.38 ± 2.95 vs. ?3.51 ± 1.66; p < 0.05) and MPA (?3.94 ± 1.66 vs. ?2.87 ± 1.04; p < 0.05) z-scores. A fetal PV z-score of ?5 predicted ductal dependence with 78 % sensitivity and 87 % specificity, and a PV z-score of ?3 showed 100 % sensitivity and 34 % specificity (p < 0.001). Fetuses with a reversed left-to-right flow across the ductus arteriosus (DA) were more likely to be ductal dependent (odds ratio, 25; p < 0.001) than those who had normal ductal flow.

Conclusions

In TOF, fetal PV and MPA z-scores and direction of the DA blood flow predict neonatal ductal dependence. Patients with fetal PV z-scores lower than ?3 or any left-to-right flow at the level of the DA should be admitted to a center where prostaglandin is available.  相似文献   
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This prospective study examined the role of premenstrual tension in producing behavioural problems in menstruating women with mental handicaps in two hospital settings. Clinical evaluation and hormonal studies were undertaken for two years, helped by the Mersey Research Grant Scheme. The main findings were that 11 women out of a random sample of 40 (27.5 per cent) showed a behaviour change for the worse clinically just prior to menstruation, in addition to having physical symptomatology and hormonal abnormalities highly suggestive of premenstrual tension. The findings and implications in care and management of such behaviour problems are discussed.  相似文献   
69.
Background: The aerosol generated by an ultrasonic scaler contains microorganisms that can penetrate into the body through the respiratory system of dental surgeons and patients. The aim of this pilot study is to evaluate and compare the efficacy of commercially available preprocedural mouthrinses containing 0.2% chlorhexidine gluconate, an herbal mouthwash, and water in reducing the levels of viable bacteria in aerosols. Methods: This single‐center, double‐masked, placebo‐controlled, randomized, three‐group parallel design was conducted over a period of 45 days. Twenty‐four patients with chronic periodontitis were divided randomly into three groups (A, B, and C) of eight patients each to receive 0.2% chlorhexidine gluconate, herbal mouthwash, and water, respectively, as a preprocedural rinse. The aerosol produced by the ultrasonic unit was collected at patient's chest area, doctor's chest area, and assistant's chest area on blood agar plates in all three groups. The blood agar plates were incubated at 37°C for 48 hours, and the total number of colony‐forming units (CFUs) was counted and statistically analyzed. Results: The results showed that CFUs in groups A and B were significantly reduced compared with group C, P <0.001 (analysis of variance). Also, CFUs in group A were significantly reduced compared with group B, P <0.05 (independent t‐test). The numbers of CFUs were highest at the patient's chest area and lowest at the assistant's chest area. Conclusion: This study suggests that a routine preprocedural mouthrinse could eliminate the majority of bacterial aerosols generated by the use of an ultrasonic unit, and that 0.2% chlorhexidine gluconate is more effective than herbal mouthwash.  相似文献   
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