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21.
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study.  相似文献   
22.
In order to benefit from antiretroviral therapy, pregnant women infected with HIV must be tested and diagnosed. Not infrequently, however, women present in labor without prior prenatal care and are thus unable to benefit fully from HIV testing and, if infected, antiretroviral therapy. In this study we evaluated the need for rapid perinatal HIV testing for untested mothers presenting in labor in a public maternal–child hospital that provides care for metropolitan Porto Alegre, Brazil, and potentially modifiable risk factors for noncompliance with national recommendations. We surveyed a consecutive sample of women who gave birth at Hospital Materno–Infantil Presidente Vargas (Presidente Vargas Mother-and-child Hospital) in August–October 2001and administered a structured questionnaire to consenting participants. The questionnaire consisted of demographic data, information on health-seeking behavior, knowledge of HIV infection, and testing during pregnancy. We confirmed information on HIV testing, syphilis, and hepatitis B by examination of the patient's prenatal records. We also obtained data regarding laboratory testing and treatment during labor and delivery (e.g., HIV testing, antiretroviral treatment, and suppression of lactation) from hospital inpatient charts. Of 214 eligible participants, 209 (98%) agreed to participate in the study. Overall 173 (83%) of the 209 participants had had a previous HIV test and 36 (17%) had not. Women with fewer pregnancies were more likely to have been tested (p = .017), as were women with lower family incomes (p = .007). No women had received rapid tests in the delivery room. Of the 209 participants, 201 (96%) had had at least one prenatal visit and 169 (81%) had had three or more visits; 12 (6%) of these reported that they had not been offered an HIV test, 5 (2%) did not know if testing had been offered or not, and 191 (95%) reported that they had been offered a test. We were able to obtain prenatal records for 190 (95%) of the 201participants who had received prenatal care. HIV testing was not mentioned in 9% of charts. Results of syphilis tests were recorded on prenatal records or hospital charts for 167 (80%)participants, and results of hepatitis B surface antigen were found for 93 (45%). Women who to 30pchad had three or more prenatal visits were significantly more likely to have been tested for to 30pcHIV (OR 46.96, 95% CI, 15.92–144.85, .0001), syphilis (OR 31.64, 95% CI, 11.81–87.42, p < .0001) or HBsAg (OR, 4.88, 95% CI, 1.91–12.99, p < .0001) than women who had had two prenatal visits or fewer. Our study showed shown that in 12% of the pregnancies included in our sample national recommendations for prenatal or perinatal testing were not followed, and in an additional 5%, HIV testing, though offered, was not obtained. These women could potentially have benefited from rapid HIV testing. As knowledge of HIV and risk factors for transmission were almost universal in our sample, we believe that the passive health-seeking behavior we observed may offer an opportunity for targeting new efforts to promote the importance of prenatal care and prenatal diagnosis of HIV.  相似文献   
23.
In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert thyroid effects through a variety of mechanisms of action, and some animal experiments and in vitro studies have focused on elucidating the mode of action of specific chemical compounds. Long-term human studies on effects of environmental chemicals on thyroid related outcomes such as growth and development are still lacking. The human exposure scenario with life long exposure to a vast mixture of chemicals in low doses and the large physiological variation in thyroid hormone levels between individuals render human studies very difficult. However, there is now reasonably firm evidence that PCBs have thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties.  相似文献   
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Candida albicans is present in the oral cavity and in the whole digestive tract of humans and other animals, being frequently related to endodontic treatment failure. The present study determined the incidence of C. albicans in the oral cavity and the susceptibility of isolates to different pH values and saturated calcium hydroxide aqueous solution at pH 12.5. Sixty-five patients attending the Endodontic Clinic at the Sagrado Cora??o University participated in the study. The collected samples were cultivated in selective media for C. albicans and the isolates were tested in terms of resistance to both alkaline pH and saturated aqueous solution of calcium hydroxide. In relation to time variables, yeast viability was assessed by the Sabouraud's agar culture and fluorescein diacetate and ethidium bromide fluorescent staining method. Results from the different pHs and experimental times, including those from different techniques measuring fungal viability, were compared using the chi-square and Fisher's exact tests (α=0.05). The yeasts became completely inviable after 48 h of contact with the calcium hydroxide solution. On the other hand, when exposed to the alkaline culture broth, the yeasts were found to be viable at pHs 9.5 and 10.5 for up to 7 days. In conclusion, C. albicans can only be completely inhibited by direct contact with saturated calcium hydroxide aqueous solution after 48 h of exposure.  相似文献   
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29.

Objectives

to verify the face validity, criterion-related validity and the reliability of two distinct forms of presentation of the instrument Measurement of Adherence to Treatment, one being for ascertaining the adherence to the use of oral antidiabetics and the other for adherence to the use of insulin, as well as to assess differences in adherence between these two modes of drug therapy.

Method

a methodological study undertaken with 90 adults with Type 2 Diabetes Mellitus. The criterion-related validity was verified using the Receiver Operating Characteristic curves; and for the reliability, the researchers calculated the Cronbach alpha coefficient, the item-total correlation, and the Pearson correlation coefficient.

Results

the oral antidiabetics and the other showed sensitivity of 0.84, specificity of 0.35 and a Cronbach correlation coefficient of 0.84. For the adherence to the use of insulin, the values found were, respectively, 0.60, 0.21 and 0.68. A statistically significant difference was found between the final scores of the two forms of the instrument, indicating greater adherence to the use of insulin than to oral antidiabetics.

Conclusion

it is concluded that the two forms of the Measurement of Adherence to Treatment instrument are reliable and should be used to evaluate adherence to drug treatment among people with diabetes mellitus.  相似文献   
30.
Anaphylaxis is an acutely presenting life‐threatening medical emergency. Surveys indicate that dentists feel inadequately able to recognize and treat anaphylaxis. This paper reviews the terminology and pathophysiology of anaphylaxis, and describes the recognition and initial management of anaphylaxis for dentists. Dentists should be able to administer intramuscular adrenaline during anaphylaxis at the appropriate dose. The role of further medical care is also explained. Six cases of anaphylaxis arising from dental oral maxillofacial surgery practice are discussed.  相似文献   
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