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101.
A 14-year-old girl with congenital heart disease underwent ventricular assist device placement before cardiac transplantation. The inability to close her abdominal fascia necessitated the placement of Prolene mesh, which subsequently became exposed and contaminated when her incision dehisced. Stable closure was obtained with Vicryl mesh and a rectus abdominis turnover flap. Her posttransplant course was notable for compression of the donor heart, necessitating prolonged open sternotomy. She failed an attempt at delayed sternal closure due to compression of the right ventricle by the sternum. In addition to standard pectoralis advancement flaps, a pedicled osseous sternal flap based on her left internal mammary artery was developed to avoid ventricular compression yet still provide some protection to the mediastinum. Alternative uses of this vascularized bone flap to assist with chest wall reconstruction are discussed. 相似文献
102.
103.
In spite of cancer screening programs, women continue to present with advanced breast cancer. How do women decide whether and when to seek an evaluation for self-discovered symptoms? This study examined 104 narratives told by 80 Anglo-, Latina-, and African-American women who participated in 1 of 16 community-based focus groups. The women's narratives contained powerful thematic messages about breast cancer and their expected behavior in the event of a self-discovered breast symptom. Narrative explanations that predicted an increased likelihood of advanced disease at diagnosis included these factors: incorrect symptom attributions and risk estimations; reluctance to consider the threat posed by the symptom; failure to tell another person about the symptom; and expectations of abandonment by male partners, deportation, prejudice, and refusal of treatment due to poverty. Stories of advanced breast cancer also told of reliance on alternative healing, concerns about overwhelming family resources, and extreme modesty that inhibited obtaining a physical examination. Interventions aimed at earlier detection of breast cancer must connect with the beliefs and assumptions embedded in these narratives, provide pragmatic solutions for perceived constraints on seeking evaluations of self-discovered symptoms, and explore the use of community narratives to confirm the value of early detection of breast cancer. 相似文献
104.
KA Cook TE Dobbs WG Hlady JG Wells TJ Barrett ND Puhr GA Lancette DW Bodager BL Toth CA Genese AK Highsmith KE Pilot L Finelli DL Swerdlow 《Canadian Metallurgical Quarterly》1998,280(17):1504-1509
CONTEXT: Acidic foods such as orange juice have been thought to be unlikely vehicles of foodborne illness. OBJECTIVE: To investigate an outbreak of Salmonella enterica serotype Hartford (Salmonella Hartford) infections among persons visiting a theme park in Orlando, Fla, in 1995. DESIGN: Review of surveillance data, matched case-control study, laboratory investigation, and environmental studies. SETTING: General community. PARTICIPANTS: The surveillance case definition was Salmonella Hartford or Salmonella serogroup C1 infection in a resident of or a visitor to Orlando in May or June 1995. In the case-control study, case patients were limited to theme park hotel visitors and controls were matched to case patients by age group and hotel check-in date. MAIN OUTCOME MEASURES: Risk factors for infection and source of implicated food. RESULTS: Sixty-two case patients from 21 states were identified. Both Salmonella Hartford and Salmonella enterica serotype Gaminara (Salmonella Gaminara) were isolated from stool samples of 1 ill person. Thirty-two case patients and 83 controls were enrolled in the case-control study. Ninety-seven percent of case patients had drunk orange juice in the theme park vs 54% of controls (matched odds ratio, undefined; 95% confidence interval, 5.2 to undefined). The orange juice was unpasteurized and locally produced. Salmonella Gaminara was isolated from 10 of 12 containers of orange juice produced during May and July, indicating ongoing contamination of juice probably because of inadequately sanitized processing equipment. CONCLUSIONS: Unpasteurized orange juice caused an outbreak of salmonellosis in a large Florida theme park. All orange juice was recalled and the processing plant closed. Pasteurization or other equally effective risk-management strategies should be used in the production of all juices. 相似文献
105.
Ca2+ entry under resting conditions may be important for contraction of vascular smooth muscle, but little is known about the mechanisms involved. Ca2+ leakage was studied in the A7r5 smooth muscle-derived cell line by patch-clamp techniques. Two channels that could mediate calcium influx at resting membrane potentials were characterized. In 110 mM Ba2+, one channel had a slope conductance of 6.0 +/- 0.6 pS and an extrapolated reversal potential of +41 +/- 13 mV (mean +/- SD, n = 8). The current rectified strongly, with no detectable outward current, even at +90 mV. Channel gating was voltage independent. A second type of channel had a linear current-voltage relationship, a slope conductance of 17.0 +/- 3.2 pS, and a reversal potential of +7 +/- 4 mV (n = 9). The open probability increased e-fold per 44 +/- 10 mV depolarization (n = 5). Both channels were also observed in 110 mM Ca2+. Noise analysis of whole-cell currents indicates that approximately 100 6-pS channels and 30 17-pS channels are open per cell. These 6-pS and 17-pS channels may contribute to resting calcium entry in vascular smooth muscle cells. 相似文献
106.
107.
VN Bhattathiri L Bindu P Remani B Chandralekha CA Davis MK Nair 《Canadian Metallurgical Quarterly》1996,41(2):139-142
The role of the propeptide sequence and a disulfide bridge between sites 1 and 122 in chymotrypsin has been examined by comparing enzyme activities of wild-type and mutant enzymes. The kinetic constants of mutants devoid of the Cys1-Cys122 disulfide-linked propeptide show that this linkage is not important either for activity or substrate specificity. However this linkage appears to be the major factor in keeping the zymogen stable against non-specific activation. A comparison of zymogen stabilities showed that the trypsinogen propeptide is ten times more effective than the chymotrypsinogen propeptide in preventing non-specific zymogen activation during heterologous expression and secretion from yeast. This feature can also be transferred in trans to chymotrypsinogen; i.e. the chymotrypsin trypsin propeptide chimera forms a stable zymogen. 相似文献
108.
In order to study the prevalence and the clinical features of renal tuberculosis associated with AIDS, we studied the renal tissue of the necropsies made in 46 AIDS patients under light microscopy. We found renal tuberculous granuloma in 11 (23%) patients (in 3 without previous diagnosis of renal or extrarenal tuberculosis) and only 4 of them presented moderate hematuria or pyuria sterile. As subclinical renal tuberculosis was frequent in this group of AIDS patients, the urine culture for Mycobacterium tuberculosis may be useful for diagnosing tuberculosis in AIDS patients. 相似文献
109.
OBJECTIVES: This study compared the relative strength of the associations of a set of structural (social, economic, and political) variables and a set of health services variables with state-level infant, neonatal, and postneonatal mortality. It also examined whether health services mediate the relationships between structural variables and state-level infant, neonatal, and postneonatal mortality. METHODS: With the state as the unit of analysis, data for all 50 states were analyzed by means of multiple regression. RESULTS: Structural variables accounted for substantially more variance in infant, neonatal, and postneonatal mortality than health services variables, and health services variables were more strongly related to infant mortality than to neonatal or postneonatal mortality. When health services variables were controlled, the strengths of the associations between the structural variables and infant, neonatal, and postneonatal mortality were reduced but remained statistically significant. CONCLUSIONS: A substantial portion of the variance in state-level infant mortality is accounted for by states' structural characteristics, which are partially mediated by health services. 相似文献
110.
LE Shields SB Uhrich CA Komarniski MH Wener TC Winter 《Canadian Metallurgical Quarterly》1996,15(11):735-739
The purpose of this retrospective study was to evaluate the utility of routine measurement of amniotic fluid alpha-fetoprotein levels at the time of second trimester genetic amniocentesis (mean gestational age, 17.3 weeks +/- 2.5 weeks standard deviation; median, 16.8 weeks; range, 15 to 22 weeks). During the study period 7174 patients underwent second trimester genetic amniocentesis. Outcome data were available in all cases. In 79 (1.1%) cases the amniotic fluid alpha-fetoprotein level was > or = 2.0 multiples of the median. Thirty-three of the 79 (42%) patients had normal ultrasonograms, and in 31 of 33 (94%) the amniotic fluid alpha-fetoprotein level was between 2.0 and 3.0 multiples of the median. Forty-six of the 79 (58%) patients had abnormal ultrasonographic findings, and of these, 82% were neural tube defects, abdominal wall defects, or cystic hygromas. Acetylcholinesterase was positive in 37 cases, all of which had abnormal ultrasonographic findings. None of the fetuses with negative findings on sonographic screening had detectable abnormalities at birth. In this study, with over 7000 patients, amniotic fluid alpha-fetoprotein and acetylcholinesterase levels did not increase the detection of fetal abnormalities. On the basis of these results, routine measurement of amniotic fluid alpha-fetoprotein level at the time of routine genetic amniocentesis (15 to 22 weeks) does not appear justified. 相似文献