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991.
992.
Farmworkers are at risk for developing occupation-related health conditions, yet healthcare use is limited. National Agricultural Workers Survey data were used to test a modification of the Behavioral Model for Vulnerable Populations on use of healthcare in the past two years and type of healthcare used. Barriers to care were examined to determine associations with use and type of use. The farmworkers (N = 2,291) were primarily foreign-born Latino/Hispanic married males who reported limited ability to read and speak English. Healthcare use in the past two years was more likely among females, those with more than six years of education, who earned an annual income of more than $15,000 annually, were authorized, non-migrant, insured, and who reported living in the US for more than two years. Healthcare system barriers were most prominent. This study provides important targets for policy and health promotion initiatives to reduce health disparities in this marginalized community.  相似文献   
993.
Background: Interracial relationships in Canada have increased over the years. However, little research has focused on comparing STI/HIV risk and condom use between those in intra- and interracial relationships, specifically among Middle Eastern-Canadians. Methods: A web-based survey was administered to Middle Eastern-Canadians. Logistic regression analysis was used to assess factors associated with consistent condom use. Analyses were stratified by partner’s race (Middle Eastern or non-Middle Eastern). Results: The analysis sub-sample consisted of 92 participants. Factors associated with consistent condom use varied between the stratified groups. Among those with Middle Eastern partners, attitude towards marriage and the family and control in the relationship were associated with condom use. Among participants with non-Middle Eastern partners, acculturation and HIV knowledge were found to be associated with condom use. Discussion: Factors associated with condom use varied between Middle Eastern-Canadians in intra- and interracial relationships. These differences illustrate the need for tailored interventions aimed at increasing condom use among this racial group.  相似文献   
994.

Purpose

To compare patient-reported quality-of-life and sexual function outcomes in women after laparoscopic supracervical hysterectomy (LSH) or total laparoscopic hysterectomy (TLH) for benign uterine disease.

Methods

Out of a cohort of 1,952 patients from a previous implementation study of LSH and TLH, 1,886 patients who had not undergone intraoperative conversion to laparotomy or were ineligible for other reasons were invited by mail to participate in this prospective, questionnaire-based follow-up study.

Results

Of the 915/1,952 (48.5 %) survey respondents included in the analysis, 788 (86.1 %) and 127 (13.9 %) had undergone LSH or TLH, respectively. Women undergoing LSH reported significantly lower pain levels (p = 0.037) and faster partial (p = 0.015) and complete (p < 0.001) resumption of normal daily activities compared to those undergoing TLH. As regards sexual function, women undergoing LSH resumed sexual activity significantly sooner (p = 0.018), rated sexual desire as higher (p = 0.023), and reported more frequently that their sexual life had improved postoperatively (p = 0.008) than did women undergoing TLH.

Conclusions

Women undergoing LSH for benign uterine disease may have better outcomes regarding certain quality-of-life and sexual function parameters than women undergoing TLH for benign uterine disease.  相似文献   
995.
996.
Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant disease characterized by progressive cerebellar ataxia and macular degeneration causing progressive blindness. It accounts for 1 to 11.6 % of spinocerebellar ataxias (SCAs) cases worldwide and for 7.4 % of SCA7 cases in Mexico. We identified a cluster of SCA7 families who resided in a circumscribed area of Veracruz and investigated whether the high incidence of the disease in this region was due to a founder effect. A total of 181 individuals from 20 families were studied. Four microsatellite markers and one SNP flanking the ATNX7 gene were genotyped and the ancestral origin and local ancestry analysis of the SCA7 mutation were evaluated. Ninety individuals from 19 families had the SCA7 mutation; all were found to share a common haplotype, suggesting that the mutation in these families originated from a common ancestor. Ancestral origin and local ancestry analysis of SCA7 showed that the chromosomal segment containing the mutation was of European origin. We here present evidence strongly suggesting that the high frequency of SCA7 in Veracruz is due to a founder effect and that the mutation is most likely of European origin with greatest resemblance to the Finnish population.  相似文献   
997.

Introduction

Cephalocele is a relatively rare cranial dysraphism characterised by herniation of intracranial structures through the skull. Surgical management is primarily necessary where a risk of infection through communication of the lesion with the intracranial space exists, a risk of rupture, or for cosmetic purposes. Cephalocele is often associated with venous anomalies such as vertical embryonic positioning of the straight sinus, splitting of the superior sagittal sinus, vein of Galen elongation, along with tenting of the tentorium [Morioka et al. Childs Nerv Syst 25:309–315, 2009]

Patients

Here, we report four cases of cephalocele with pre-operative MRI imaging retrospectively studied, demonstrating associated venous anomalies. Three of these patients went on to have uncomplicated, corrective surgery, while one was managed conservatively.

Results

All four cases demonstrated the main venous drainage going through a persistent falcine sinus to drain into the superior sagittal sinus. Upward tenting of the tentorium was observed in three cases (cases 1, 3 and 4). Two of our cases demonstrated other venous anomalies frequently reported in the literature, namely splitting of the superior sagittal sinus and absence of the transverse sinus (case 1) and communication of the cephalocele with the superior sagittal sinus and absence of the straight sinus (case 2).

Conclusion

The association between cephalocele and venous anomalies suggests that pre-operative MRI should be mandatory for a full evaluation of a suspicious midline cranial lesion in order to evaluate the safety of corrective surgery.  相似文献   
998.
Acute megakaryoblastic leukemia (AMKL) is a subtype of acute myeloid leukemia associated with a poor prognosis. However, there are relatively few insights into the genetic etiology of AMKL. We developed a screening assay for mutations that cause AMKL, based on the hypothesis that constitutive activation of STAT5 would be a biochemical indicator of mutation in an upstream effector tyrosine kinase. We screened human AMKL cell lines for constitutive STAT5 activation, and then used an approach combining mass spectrometry identification of tyrosine phosphorylated proteins and growth inhibition in the presence of selective small molecule tyrosine kinase inhibitors that would inform DNA sequence analysis of candidate tyrosine kinases. Using this strategy, we identified a new JAK2T875N mutation in the AMKL cell line CHRF-288-11. JAK2T875N is a constitutively activated tyrosine kinase that activates downstream effectors including STAT5 in hematopoietic cells in vitro. In a murine transplant model, JAK2T875N induced a myeloproliferative disease characterized by features of AMKL, including megakaryocytic hyperplasia in the spleen; impaired megakaryocyte polyploidization; and increased reticulin fibrosis of the bone marrow and spleen. These findings provide new insights into pathways and therapeutic targets that contribute to the pathogenesis of AMKL.  相似文献   
999.

Objectives

This study evaluated the influence of different exposure times to saliva in situ in comparison with an antioxidant treatment on composite resin bond strength to human enamel restored after tooth bleaching.

Material and Methods

Forty human teeth specimens measuring 5x5 mm were prepared and randomly allocated into 5 groups with 8 specimens each: Gct (control group, restored on unbleached enamel); Gbl (restored immediately after bleaching); Gsa (bleached, treated with 10% sodium ascorbate gel for 60 min and restored); G7d (bleached, exposed to saliva in situ for 7 days and restored); and G14d (bleached, exposed to saliva in situ for 14 days and restored). Restored samples were cut into 0.8 mm2 sticks that were tested in microtensile. Specimens were microscopically analyzed and failure modes were classified as adhesive, cohesive, or mixed. Pretest and cohesive failures were not considered in the statistical analysis, which was performed with one-way ANOVA and Tukey''s post-hoc test (α=0.05), with the dental specimen considered as the experimental unit.

Results

Mean bond strength results found for Gbl in comparison with Gct indicated that bleaching significantly reduced enamel adhesiveness (P<0.01). However, no statistically significant differences were found between Gct, Gsa and G7d (P>0.05). Bond strength found for G14d was significantly higher than for Gsa (P<0.01). Fractures modes were predominantly of a mixed type.

Conclusions

Bonding strength to bleached enamel was immediately restored with the application of sodium ascorbate and exposure to human saliva in situ for at least 7 days. Best results were obtained with exposure to human saliva in situ for 14 days. Treatment with sodium ascorbate gel for 60 min may be recommended in cases patients cannot wait for at least 7 days for adhesive techniques to be performed.  相似文献   
1000.
This investigation uses a system for inducing and detecting anti-tetanus toxoid antibody (anti-TT) synthesis to study specific antibody (Ab) synthesis by bone marrow mononuclear cells (MC). We measured the amounts of anti-TT secreted and the number of B cells secreting antibody (Ab). The ELISA plaque detects single B cells secreting specific Ab. The results show that (1) spontaneous anti-TT secretion by MC is higher than spontaneous anti-TT secretion by peripheral blood lymphocytes (PBL) using an ELISA plaque (P<0.01); (2) spontaneous anti-TT production by MC correlated with the serum anti-TT titers as measured by an ELISA (r=0.75,P=0.005); (3) two types of marrow B cells were identified—one that spontaneously secretes anti-TT and another that produces anti-TT after TT-stimulation; (4) the frequency of anti-TT-secreting B cells is higher in MC than in PBL; (5) the amount of Ab secreted per marrow B cell is not different from that secreted by a peripheral B cell; and (6) marrow B cells could be induced to produce anti-TTin vitro up to 10 months without added cytokines. These results show that bone marrow is a major repository for differentiated B cells that spontaneously produce Abs to maintain circulating Abs titers and for memory B cells that can be induced to produce specific Ab.  相似文献   
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