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621.
To assess the effects of environmental exposures to trace metals on the incidence of preeclampsia, concentrations of lead (Pb), antimony (Sb), manganese (Mn), mercury, cadmium, cobalt and zinc in umbilical cord blood (UCB) and mother whole blood (MWB) were measured in 396 postpartum women without occupational exposure to metals in Tehran, Iran, using inductively coupled plasma mass spectrometry. Mother's ages ranged from 15 to 49 (mean 27) years. Preeclampsia was diagnosed in 31 subjects (7.8%). Levels of Pb, Sb and Mn in UCB were significantly higher in preeclampsia cases [mean+/-SD of 4.30+/-2.49 microg/dl, 4.16+/-2.73 and 46.87+/-15.03 microg/l, respectively] than in controls [3.52+/-2.09 microg/dl, 3.17+/-2.68 and 40.32+/-15.19 microg/l, respectively] (P<0.05). The logistic regression analysis revealed that one unit increase in the common logarithms of UCB concentration of Pb, Sb or Mn led to increase in the risk of preeclampsia several-fold; unit risks (95% CI) were 12.96 (1.57-107.03), 6.11 (1.11-33.53) and 34.2 (1.81-648.04) for Pb, Sb and Mn, respectively (P<0.05). These findings suggest that environmental exposure to Pb, Sb and Mn may increase the risk of preeclampsia in women without occupational exposure; levels of metals in UCB to be sensitive indicators of female reproductive toxicity as compared with those in mother MWB. Further studies are necessary to confirm these findings, especially on Sb and Mn.  相似文献   
622.
A 23-year-old man was admitted to our hospital for evaluation of syncope and intracardiac masses. Echocardiography revealed three masses in the right ventricle and one in the left ventricle. The largest mass, 4 by 5 cm, occupied the right ventricular outflow tract and prolapsed through the pulmonary valve orifice. Right ventricular systolic pressure was 65 mmHg. A soft mass, 4 by 5 cm, was found on the left subcostal abdominal wall and multiple pigmented spots on the face and trunk. Histological examination of the resected tumors, including the abdominal soft mass, were consistent with myxoma. The combination of multiple cardiac and abdominal wall myxomas and pigmented skin lesions in this young patient is considered to be a diagnostic feature of Carney complex.  相似文献   
623.
When a speaker's voice returns to one's own ears with a 200-ms delay, the delay causes the speaker to speak less fluently. This phenomenon is called a delayed auditory feedback (DAF) effect. To investigate neural mechanisms of speech processing through the DAF effect, we conducted a functional magnetic resonance imaging (fMRI) experiment, in which we designed a paradigm to explore the conscious overt-speech processing and the automatic overt-speech processing separately, while reducing articulatory motion artifacts. The subjects were instructed to (1) read aloud visually presented sentences under real-time auditory feedback (NORMAL), (2) read aloud rapidly under real-time auditory feedback (FAST), (3) read aloud slowly under real-time auditory feedback (SLOW), and (4) read aloud under DAF (DELAY). In the contrasts of DELAY-NORMAL, DELAY-FAST, and DELAY-SLOW, the bilateral superior temporal gyrus (STG), the supramarginal gyrus (SMG), and the middle temporal gyrus (MTG) showed significant activation. Moreover, we found that the STG activation was correlated with the degree of DAF effect for all subjects. Because the temporo-parietal regions did not show significant activation in the comparisons among NORMAL, FAST, and SLOW conditions, we can exclude the possibility that its activation is due to speech rates or enhanced attention to altered speech sounds. These results suggest that the temporo-parietal regions function as a conscious self-monitoring system to support an automatic speech production system.  相似文献   
624.
PURPOSE: To test the hypotheses that, in mice, breathing carbogen (95% O(2)-5% CO(2)) oxygenates the retina better than breathing 100% oxygen, the superior hemiretinal oxygenation response to carbogen inhalation is subnormal early in diabetes, and diabetes-induced elevation of retinal protein kinase C (PKC)-beta contributes to this pathophysiology. METHODS: Retinal oxygenation response (DeltaPO(2)) was measured using functional magnetic resonance imaging (MRI) and either carbogen or 100% oxygen inhalation challenge in C57BL/6J control (C) mice. Retinal DeltaPO(2) during carbogen breathing was also measured in PKCbeta knockout (C57BL6-Prkcb1; [KO]), 4 month C57BL/6J diabetic (D), and 4-month diabetic PKCbeta KO (D+KO) mice. Retinal PKCbeta protein expression was assessed by Western analysis. RESULTS: In C mice, retinal DeltaPO(2) during carbogen breathing was significantly greater (P < 0.05) than during oxygen breathing. In D mice, DeltaPO(2) during carbogen breathing was significantly lower than normal in the superior, but not the inferior, hemiretina and was normal (P > 0.0 5) in the KO group. In the D+KO mice DeltaPO(2) was normal (P > 0.05) only at distances less than 1.5 mm from the optic nerve head. PKCbeta expression was elevated in the retina in diabetes (P < 0.05), but was significantly decreased (P < 0.05) in D+KO mice. CONCLUSIONS: The present study confirms that, in the mouse, retinal DeltaPO(2) patterns during different inhalation challenges or in the presence of diabetes are similar to what has been reported in rats. Diabetes-induced elevation of PKC appears to contribute only focally to subnormal retinal DeltaPO(2). This raises the possibility that PKC inhibition therapy may be only regionally effective in treating retinal pathophysiology associated with diabetic retinopathy.  相似文献   
625.
We investigated the clinicopathological significance of aberrant methylation of the retinoic acid receptor-beta2 (RARbeta2), RAS association domain family 1A (RASSF1A) and fragile histidine triad (FHIT) genes located on choromosome 3p in 120 patients with primary non-small cell lung cancer (NSCLC) by a methylation-specific PCR method. Aberrant methylation of these was detected in 31 (26%), 35 (29%) and 43 (36%) tumors, respectively. There was no correlation with the methylation status of any of the genes. RARbeta2 methylation was more frequently observed in patients with a smoking history (19 of 61, 31%) than in patients without one (3 of 29, 10%, P = 0.0373). RARbeta2 methylation was also preferentially observed in advanced stage NSCLC (12 of 71 (17%) in stage I, 5 of 15 (33%) in stage II, 11 of 24 (46%) in stage III, and 3 of 8 (38%) in stage IV, P = 0.0057 (stage I versus II, III,and IV)). FHIT methylation was predominantly detected in tumors with vascular invasion (21 of 44, 48%, P = 0.0703) or lymphatic permeation (28 of 59, 47%, P = 0.0115). RASSF1A methylation was more frequently observed in adenocarcinomas (28 of 72, 39%) than in squamous cell carcinomas (6 of 45, 13%, P = 0.0033). These results indicate that aberrant methylation of the candidate tumor suppressor genes on 3p plays a respective role in the pathogenesis of NSCLC.  相似文献   
626.
This study attempted to identify forms of stigma against individuals with mental disorders and related factors. The subjects comprised 2632 people living in the area covered by the K health center in N prefecture. Factor analysis of the Mental Disorder Prejudice Scale (1211 valid responses) identified three factors: 'rejection', 'peculiarity' and 'human rights alienation'. Regression analysis revealed that age, welfare activities, an active problem-solving attitude, lecture attendance, and previous contact, exerted independent effects with respect to 'rejection'. These results suggest the importance of disseminating accurate information and creating more opportunities for people to have meaningful interactions with people with mental disorders in order to dispell the stigma.  相似文献   
627.
Purpose The common hepatic duct is usually divided during the early stage of pancreaticoduodenectomy. However, abrupt, complete, and prolonged closure of the proximal common duct stump can cause liver damage in the course of this long operation, resulting in postoperative liver dysfunction and associated complications. Here, we investigate this phenomenon further.Methods We performed intraoperative continuous external bile drainage (IBD) in 43 consecutive patients (drainage group) and compared postoperative liver enzyme levels, morbidity including liver dysfunction, and outcomes with those of a control group (n = 41).Results There were no complications associated with IBD catheter insertion in this series. The drainage group had significantly lower transaminase levels within the first 7 postoperative days (PODs) than the control group. Postoperative liver dysfunction was confirmed in six patients from the control group and in one patient from the drainage group (P = 0.04). However, there were no significant differences between these two groups in terms of postoperative morbidity (other than liver dysfunction), relaparotomy, and in-hospital mortality rates.Conclusion Intraoperative continuous external bile drainage failed to improve the overall morbidity and mortality rates in this series. However, our findings showed that prolonged intraoperative complete closure of the common hepatic duct contributed to postoperative liver dysfunction in most patients and that IBD, which is easy and safe to perform, could reduce intra-operative liver damage and prevent postoperative liver dysfunction.  相似文献   
628.
BACKGROUND: With the current shortage of donors, there is a critical need to optimally use "less-than-ideal" donors for pancreas transplantation. Objective and rapid means for assessing graft viability and suitability for transplantation are mandatory. This study examined the possibility of graft viability assessment and posttransplant outcome prediction using (31)P-nuclear magnetic resonance (NMR) spectroscopy combined with the two-layer cold-storage method (TLM). METHODS: Canine pancreas grafts were preserved with TLM for 24 hours after 0, 60, or 120 minutes of warm ischemia (groups 1, 2, or 3, respectively). After preservation, we determined intragraft phosphate metabolites noninvasively using (31)P-NMR spectroscopy. Time required for this assessment was 5 minutes. Because our previous studies demonstrated that all grafts in groups 1 and 2 were successfully transplanted (the viable group), whereas all in group 3 failed to survive (the nonviable group), the possibility of posttransplant outcome prediction was examined on the basis of the comparison between these two groups. RESULTS: The ratios of inorganic phosphate/gamma-adenosine triphosphate (Pi/gamma-ATP) and Pi/beta-ATP reflected the extent of graft damage, and the differences were statistically significant among groups 1, 2, and 3. On the basis of analyses of receiver operator characteristic curves, the optimum cutoff levels between the viable and nonviable groups were 1.6 and 2.2 for Pi/gammaATP and Pi/betaATP, respectively. The accuracy rates of these ratios were both 83%. CONCLUSION: (31)P-NMR spectroscopy combined with TLM preservation could provide an objective, rapid, and possibly noninvasive means to assess pancreas graft viability and to determine suitability of damaged pancreata for organ transplantation.  相似文献   
629.
BACKGROUND/AIMS: This study was designed to evaluate risk factors influencing pancreatic leakage and pancreatic leakage-related mortality in a medium-volume hospital. METHODOLOGY: We retrospectively reviewed the clinical records of 107 patients who underwent pancreaticoduodenectomy at the Kobe University Hospital. Fourteen predictive factors for pancreatic leakage and the pancreatic leakage-related mortality were evaluated using univariate and multivariate logistic regression models. RESULTS: In univariate analysis, the degree of pancreatic fibrosis, type of resection (PD/PPPD), anastomosis techniques (invagination or duct-to-mucosa anastomosis), anastomosis sites (jejunum/stomach), and the presence of congestion in anastomosis sites significantly influenced pancreatic leakage, and the degree of pancreatic fibrosis influenced pancreatic leakage-related mortality. Multivariate logistic regression analysis revealed that congestion in anastomosis sites was the strongest parameter for pancreatic leakage. Univariate analysis of the patients with normal/mild fibrosing pancreas revealed that pancreatic leakage was influenced by type of resection, anastomosis techniques, anastomosis sites, congestion in anastomosis sites and the management of pancreas parenchyma. CONCLUSIONS: In a medium-volume hospital, reconstruction after pancreaticoduodenectomy should be performed with careful attention to pancreas and anastomosis sites. In the patients with normal/mild fibrosing pancreas, duct-to-mucosa anastomosis without suturing the pancreas parenchyma may be a useful technique for reconstruction.  相似文献   
630.
Objectives. The purpose of this study was to evaluate whether a serotonin blocker, sarpogrelate, improves exercise capacity as a result of vasodilation of coronary collateral channels in patients with effort angina.

Background. Serotonin has been reported to decrease coronary collateral blood flow by collateral vasoconstriction in a canine model, suggesting that platelet activation in feeding coronary arteries of the collateral network has the potential to cause collateral vasoconstriction.

Methods. The subjects consisted of 22 patients with effort angina and reproducible ischemic threshold (group A, 11 patients with thrombolysis in myocardial infarction (TIMI) grade 2 or 3 flow of the ischemia-related coronary artery and Rentrop’s collateral index 0 or 1; group B, 11 patients with TIMI grade 0 or 1 flow and Rentrop’s collateral index 2 or 3). We repeated the symptom-limited treadmill exercise test using the Balke–Ware protocol and exercise tetrofosmin myocardial perfusion scintigraphy with and without pretreatment with 200 mg orally administered sarpogrelate. Each exercise test was performed at 9:00 a.m. on different days. The order of tests with and without sarpogrelate was randomized.

Results. In group A, sarpogrelate increased neither exercise time at 0.1 mV ST depression nor double product at 0.1 mV ST depression. In contrast, in group B sarpogrelate increased the exercise duration at 0.1 mV ST depression from 181 ± 112 (SD) to 248 ± 131 s (p < 0.05) and also increased the double product at 0.1 mV ST depression by 21% (p < 0.01). The severity score using myocardial perfusion scintigraphy at the same workload was significantly (p < 0.01) decreased by 37% in group B, but not in group A (11%), due to the sarpogrelate treatment.

Conclusions. Sarpogrelate augments flow reserve of the collateral circulation and improves exercise capacity in anginal patients with well-developed collaterals. These findings indicate that a serotonin blocker, sarpogrelate, is useful not only as an antiplatelet drugs, but as an antianginal drug.  相似文献   

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