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41.
A competitive type-specific enzyme-linked immunosorbent assay (ELISA) for herpes simplex virus type 2 (HSV-2) antibody was developed using an infected cell antigen and a monoclonal antibody to glycoprotein G-2. This assay has been validated for use for epidemiological studies using a large panel of sera collected in rural Uganda and a panel of 143 sera characterised previously by Western blotting, the 'gold standard' for HSV type-specific serology. This evaluation was found to have a sensitivity of 96% and a specificity of 91% in comparison with Western blot on 143 sera from clinic patients. The ELISA had a sensitivity of 93% and a specificity of 91% in comparison with Western blot on 495 sera collected in Uganda. The assay showed good reproducibility and a low percentage of sera gave equivocal results, indicating its suitability for epidemiological studies.  相似文献   
42.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
43.
Advances in techniques of molecular biology have made possible the amplification of specific genes from single cells. This has a major clinical application in preimplantation diagnosis of monogenic disorders. However, the incidence of allele specific amplification failure (allele drop out) in heterozygous single cells can lead to misdiagnosis and the transfer of affected embryos. Few studies have been done to investigate the actual cause of allele drop out, although some investigators have succeeded in reducing but not eliminating it. Here we report the efficiency of amplifying both alleles in heterozygous cells lysed according to two different protocols. A total of 177 heterozygous cells from carriers of cystic fibrosis (CF) and haemoglobin C (HbC) were lysed using two different lysis buffers. Interestingly none of the cells that were lysed with sodium dodecyl sulphate/proteinase K showed any example of allele specific amplification failure whereas in those lysed by KOH/dithiothreitol it was present in 17.6 and 4.7% of the CF and HbC cells respectively. Our results suggest that the phenomenon of allele specific amplification failure is at least in part dependent on the lysis buffer used.   相似文献   
44.
Individuals with sickle cell disease experience a variety of psychosocial issues, some of which lead to maladjustments. To gather baseline data on coping and adjustment by a group of individuals over 30 years of age, a pilot study was conducted with 30 patients followed routinely at the Duke University Comprehensive Sickle Cell Center. The purpose of the study was to characterize such psychosocial parameters as coping behaviors, education, employment, group affiliation, health beliefs, marital status, parenting and perceptions regarding the disease. Using Erickson's stage of development as a point of reference, the middle adulthood stage was used as a theoretical framework for explaining and interpreting the results of this study. Study results reflect that, on the whole, the participants employed a wide variety of life skills to promote positive psychological and physical well being. These data suggest that this population of sickle cell disease patients have attained a reasonable level of psychosocial adjustment and many are leading productive lives. However, the minority of patients, who use the health care facilities more frequently, might lead one to speculate otherwise.  相似文献   
45.
BACKGROUND: Genetic background has a major influence on the manifestation of multifactorial diseases such as hypertension in which severe complications may be caused through an interaction with additional factors, which may be genetically determined. We have previously described a genetic model of malignant hypertension (MH) in rats carrying the mouse Ren2 gene (TGRmRen2-27), in which the phenotype is dependent on the genetic background. METHODS: Using a single homozygous TGRmRen2-27 male as transgene donor, we produced two F1 populations with (a) 100% penetrance of MH in progeny heterozygous for the Fischer F344 genetic background and (b) 58.5% penetrance in progeny heterozygous for the Lewis genetic background. To identify the modifier loci affecting the phenotype, a cohort of 252 males was produced by breeding the same single male with Fischer-Lewis F1 females. The progeny were phenotyped for clinical and pathological features of MH. RESULTS: Genome-wide screening and quantitative trait loci (QTL) analysis identified two loci, on chromosome 10 (LOD 4.4) and on chromosome 17 (LOD 3.9) close to the Ace and At1 genes, respectively, which contribute to the lethal MH phenotype. Their influence on mortality was consistent with a multiplicative effect of the two loci. In addition, we found higher plasma angiotensin-converting enzyme activity in progeny receiving the Fischer allele than in progeny receiving the Lewis allele (123.5 +/- 9.5 vs. 91.8 +/- 4.9 U/liter, P < 0.01), suggesting the association of angiotensin-converting enzyme and MH. CONCLUSIONS: Our study demonstrates the application of a transgene as a "major gene" to facilitate the identification of modifier loci, which can affect the phenotype of MH, and reveals Ace and At1 as candidate genes involved in the manifestation of the MH phenotype.  相似文献   
46.
In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control  相似文献   
47.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

48.
Use of methotrexate in juvenile idiopathic arthritis.   总被引:8,自引:0,他引:8  
Methotrexate (MTX) has transformed the outlook for children with juvenile idiopathic arthritis (JIA). Most of the evidence from uncontrolled clinical trials suggests that MTX is an effective agent for treating active JIA. Data from controlled clinical trials suggests that MTX has statistically significant effects on patient centred disability measures in JIA patients with active arthritis. Although we would like a much larger study directed evidence base for our use of the drug, the studies that have been done are sound and have been followed by a change in clinical expectations and advice that speak of qualitative evidence from clinical practice, confirming the scientifically acquired data. Randomised controlled multicentre trials using sufficient numbers of patients, including functional assessment and quality of life measures, are needed to confirm the long term efficacy and safety of MTX in JIA.  相似文献   
49.
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
50.
Hypospadias trends in two US surveillance systems   总被引:6,自引:0,他引:6  
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted.  相似文献   
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