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101.
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Management of intra-articular calcaneal fractures remains a debated topic in orthopedics, with operative fixation often held in reserve due to concerns regarding perioperative morbidity and potential complications. The purpose of this study was to identify the characteristics of patients who developed surgical complications to inform the future stratification of patients best suited to operative treatment for intra-articular calcaneal fractures. All patients who underwent open reduction and internal fixation of calcaneal fractures utilizing the Sinus Tarsi approach between March 2014 and July 2018 were identified using theatre records. Patient imaging was used to assess pre- and postoperative fracture geometry with computed tomography used for preoperative planning. Each patient's clinical presentation was established through retrospective analysis of medical records. Patients provided verbal consent to participation and patient reported outcome measures were recorded using the Maryland Foot Score. Fifty-eight intra-articular calcaneal fractures (53 patients; 5 bilateral, mean age = 46.91 years) with a mean follow-up of 35.4 months (6-57) were included. Five patients (9.4%) had wound complications; 2 superficial (3.7%), 3 deep (5.6%); 4 of whom were smokers. Smokers were statistically more likely to have wound infections than nonsmokers (p = .04). Intra-articular fractures of the calcaneus should be considered for surgical intervention in order to improve long-term functional outcomes. The Sinus Tarsi approach provides the potential to decrease the operative complication rate whilst maintaining adequate fixation, however, the decision to surgically manage these fractures should be carefully balanced against the risk of postoperative complications. This increased risk of complication associated with smoking may tip the balance against benefit from surgical management.  相似文献   
103.
Population‐based indicators of the coverage of key elements of high‐quality family planning services are tracked via household surveys with female respondents, yet little work has been done to establish their validity. We take advantage of existing data sets from Cambodia and Kenya to compare women's responses at exit interviews following a health facility visit against the observations of a trained third‐party observer during the visit. The results, which treat the observations as the reference standard, show that indicators that measure contraceptive methods received are accurately reported while indicators of whether the woman received her preferred method and whether information was “discussed” or “explained” during counseling are less reliably reported. Studies designed explicitly to assess the validity of family planning questions in household surveys, especially questions in large survey programs critical for monitoring demographic trends and programmatic coverage, are needed.  相似文献   
104.
Members of 183 families (biological parents and one adult offspring) completed questionnaires on their quantity and frequency of alcohol use, what they would consider a "normal" quantity-frequency of alcohol use, "problem" quantity-frequency of use, flushing after alcohol use, and other expected physiological and subjective responses to alcohol. Within individuals, own quantity-frequency of alcohol use was moderately negatively correlated with flushing after one drink or less ("fast flushing"), but more highly positively correlated with judged normal alcohol use and with expected subjective effects. Spouse resemblances were low for quantity-frequency of alcohol use and flushing, but high for alcohol use norms and expected physiological and subjective responses. Parent-offspring resemblances were low to moderate for own alcohol use and flushing, but moderate to high for expected physiological and subjective effects. These results were discussed in terms of the effects of genetically transmitted flushing after alcohol use and culturally transmitted alcohol norms and expectations on alcohol use.  相似文献   
105.
Mitotic gene conversions, among other recombinagenic events,can play an important role in the multistep process of carcinogenesis.The ability of chemicals to induce such gene conversions caneasily be monitored in the Saccharomyces cerevisiae tester strainYHE2, a derivative of strain D7. For the detection of drug-inducedgene conversions, two mutations in the TRP5 locus are used,trp5–12 and trp5–27. Here we report on the characterizationof the stable allele trp5–27. Our analysis revealed tworelevant mutations in trp5–27: (a) a transition C to Tat position 121 after ATG that results in an amber stop codonand abolishes gene expression and (b) a transversion A to Tat position 1555 that creates an ochre stop codon. Simultaneousamber and ochre suppression with the suppressors SUP3 and SUP11,respectively, was capable of relieving the tryptophan-requiringphenotype of strains carrying the trp5–27 allele. Thesefindings have implications on the length of gene conversiontracts in conversion events between trp5–12 and trp5–27:conversion tracts can cover several kilobases, if the site ofthe mutation in trp5–12 lies outside of the positionsmutated in trp5–27. Conversely, the maximal length islimited to 1435 bp, if the mutation in trp5–12 is locatedbetween the positions mutated in trp5–27. 1To whom correspondence should be addressed  相似文献   
106.
107.
The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown.  相似文献   
108.
Coalescence of the cerebral ventricles with formation of a single forebrain ventricle is described in an unusual case of agenesis of the corpus callosum with dehiscent fornices and severe hydrocephalus. The cerebral hemispheres were fully cleaved. The detached fornices were widely separated from the thalami. The membrana tectoria was retroverted over the midbrain and cerebellum, where it joined the fornices and merged with a curved membranous ependymal dome which, at a great distance, circumvented the thalami as it extended toward the anterior commissure. Other anomalies included arhinencephaly, multiple subependymal heterotopias, and Dandy-Walker malformation. Similar malformations have been described as interhemispheric cysts, as (holo)prosencephaly, or as midline telencephalic dysgenesis. The basic features of prosencephaly and agenesis of the corpus callosum are reviewed and compared to the present case.  相似文献   
109.
Summary The use of the conventional combination oral contraceptives (containing ethinyl-estradiol and a progestin) is associated with reduced risk of ovarian and endometrial cancer. However, prolonged use of these pills before first term pregnancy apparently increases the risk of pre menopausal breast cancer. We propose that the pineal gland hormone melatonin, combined with a progestin, as a new and novel oral contraceptive combination might prevent breast cancer in long term users. This hypothesis is based on the assumption that women have a propensity to develop breast cancer which correlates with number of ovulatory cycles over their lifetime. In evolution, the phylogenetic point at which women became sensitive to breast cancer evolved at a transfer point of the mechanism of ovulation from seasonal ovulation, which is still common in many mammalian species, to the current human pattern of continuous ovulatory cycles. We suggest that melatonin/ovariansteroid contraceptive will restore the lost mechanism of endogenous anovulation, and thus, by preventing continuous epithelial breast cell proliferation, will reduce the risk of breast cancer in long-term users.  相似文献   
110.
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