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61.
The determinants that underlie a healthy or unhealthy pregnancy are complex and not well understood. We assess the relationship between the built environment and maternal psychosocial status using directly observed residential neighborhood characteristics (housing damage, property disorder, tenure status, vacancy, security measures, violent crime, and nuisances) and a wide range of psychosocial attributes (interpersonal support evaluation list, self-efficacy, John Henryism active coping, negative partner support, Perceived Stress Scale, perceived racism, Center for Epidemiologic Studies—Depression) on a pregnant cohort of women living in the urban core of Durham, NC, USA. We found some associations between built environment characteristic and psychosocial health varied by exposure categorization approach, while others (residence in environments with more rental property is associated with higher reported active coping and negative partner support) were consistent across exposure categorizations. This study outlines specific neighborhood characteristics that are modifiable risk markers and therefore important targets for increased research and public health intervention. 相似文献
62.
Pedro Cavaleiro Miranda Mikhail Lomarev Mark Hallett 《Clinical neurophysiology》2006,117(7):1623-1629
OBJECTIVE: To investigate the spatial distribution of the magnitude and direction of the current density in the human head during transcranial direct current stimulation (tDCS). METHODS: The current density distribution was calculated using a numerical method to implement a standard spherical head model into which current was injected by means of large electrodes. The model was positioned in 'MNI space' to facilitate the interpretation of spatial coordinates. RESULTS: The magnitude and direction of the current density vector are illustrated in selected brain slices for four different electrode montages. Approximately half of the current injected during tDCS is shunted through the scalp, depending on electrode dimension and position. Using stimulating currents of 2.0 mA, the magnitude of the current density in relevant regions of the brain is of the order of 0.1 A/m2, corresponding to an electric field of 0.22 V/m. CONCLUSIONS: Calculations based on a spherical model of the head can provide useful information about the magnitude and direction of the current density vector in the brain during tDCS, taking into account the geometry and position of the electrodes. Despite the inherent limitations of the spherical head model, the calculated values are comparable to those used in the most recent in vitro studies on modulation of neuronal activity. SIGNIFICANCE: The methodology presented in this paper may be used to assess the current distribution during tDCS using new electrode montages, to help optimize montages that target a specific region of the brain or to preliminarily investigate compliance with safety guidelines. 相似文献
63.
Background
Laparoscopic Roux-en-Y gastric bypass (LRYGB) is currently the gold standard bariatric procedure for the treatment of morbid obesity. Laparoscopic sleeve gastrectomy (LSG) is a relatively innovative procedure which has been increasingly applied lately as a sole bariatric procedure. A randomized trial was conducted in a Greek population to evaluate perioperative safety and 3-years results. 相似文献64.
Miranda N Araji OA Gutiérrez-Martín MA Rodríguez-Caulo EA Barquero JM Valenzuela LF 《The Annals of thoracic surgery》2011,92(2):729-731
Transcatheter aortic valve implantation by an apical approach has been developed as an alternative to conventional aortic valve replacement. Complications with these relatively new procedures are being reported. We report a case of transapical transcatheter aortic valve implantation, in which a pseudoaneurysm at the apex of the left ventricle as a complication of the procedure developed in the patient and was treated without surgery. The defect spontaneously closed. 相似文献
65.
Kolkman RG Mulder MJ Glade CP Steenbergen W van Leeuwen TG 《Lasers in surgery and medicine》2008,40(3):178-182
BACKGROUND AND OBJECTIVE: To optimize laser therapy of port-wine stains (PWSs), information about the vasculature as well as lesion depth is valuable. In this study we investigated the use of photoacoustic imaging (PAI) to obtain this information. STUDY DESIGN/MATERIALS AND METHODS: PAI uses pulsed light to generate ultrasound upon absorption of short light pulses by blood. In this study we used PAI to image vasculature in PWSs in three human volunteers. Two-dimensional imaging (scan direction vs. depth) was carried out by scanning a double-ring photoacoustic sensor over the tissue surface. RESULTS: In the photoacoustic images we observed an increased photoacoustic signal intensity at the locations of the PWS that is associated with increased vascularization. From the obtained images we measured the thickness of the vascular layer and estimated lesion depth. In some cases single vessels could be observed at the position of the PWS whereas in other cases the PWS appeared as a region with large photoacoustic signal intensity. CONCLUSIONS: PAI has the potential to reveal information about the lesion depth as well as thickness of the vascular layer. 相似文献
66.
Combined endovascular treatment of dissecting vertebral artery aneurysms by using stents and coils 总被引:13,自引:0,他引:13
OBJECT: With the recent development and refinement of endovascular stents, the significant potential for these devices in the treatment of wide-necked dissecting and fusiform aneurysms has become apparent. In this article the authors report on the use of stents and coils to treat dissecting and fusiform vertebral artery (VA) aneurysms. METHODS: Eight consecutive patients harboring eight dissecting aneurysms and one fusiform aneurysm of the VA were succesfully treated using a procedure in which the authors inserted an intravascular stent and secondary endosaccular coils when needed. In all but one patient complete aneurysm occlusion was achieved, and in all cases there was no neurological complication. Follow-up angiography examinations were performed in all patients (mean duration of follow-up angiography review 13.1 months, range 3-42 months). The patients remained stable throughout the clinical follow-up period (mean 14.1 months, range 4-42 months). No rebleeding was recorded. CONCLUSIONS: At present this combined approach represents a reliable and safe alternative for the treatment of VA dissecting aneurysms, especially in patients who cannot tolerate occlusion tests. 相似文献
67.
68.
Dehghan A Kardys I de Maat MP Uitterlinden AG Sijbrands EJ Bootsma AH Stijnen T Hofman A Schram MT Witteman JC 《Diabetes》2007,56(3):872-878
C-reactive protein (CRP) has been shown to be associated with type 2 diabetes, but whether CRP has a causal role is not yet clear. We examined the association in the Rotterdam Study, a population-based prospective cohort study. The association of baseline serum CRP and incident diabetes during follow-up was investigated, and a meta-analysis was conducted on the BMI-adjusted relation of CRP and diabetes. Furthermore, the association of CRP haplotypes with serum CRP and risk of diabetes was assessed. The age- and sex-adjusted hazard ratio for diabetes was 1.41 (95% CI 1.29-1.54) per 1 SD increase in natural logarithm of CRP, and it was 1.88, 2.16, and 2.83 for the second, third, and fourth quartiles of CRP, respectively, compared with the first quartile. The risk estimates attenuated but remained statistically significant after additional adjustment for obesity indexes, which agreed with the results of the meta-analysis. The most common genetic haplotype was associated with a significantly lower CRP level compared with the three other haplotypes. The risk of diabetes was significantly higher in the haplotype with the highest serum CRP level compared with the most common haplotype (OR 1.45, 95% CI 1.08-1.96). These findings support the hypothesis that serum CRP enhances the development of diabetes. 相似文献
69.
Cardoso-Júnior A Coelho LG Savassi-Rocha PR Vignolo MC Abrantes MM de Almeida AM Dias EE Vieira Júnior G de Castro MM Lemos YV 《Obesity surgery》2007,17(2):236-241
Background It has been suggested that obesity is associated with an altered rate of gastric emptying. The objective of the present study
was to determine whether the rates of solid and semi-solid gastric emptying differ between morbidly obese patients and lean
subjects.
Methods The Gastric-emptying time (GET) of solid and semi-solid meals were compared between lean healthy subjects and morbidly obese
patients enrolled in two previously published studies. GET of solid and semi-solid meals was measured using the 13C-octanoic acid breath test and 13C-acetic acid breath test, respectively, in 24 lean and 14 morbidly obese individuals of both sexes. Student t-test was used to compare the mean data between the lean and morbidly obese groups. The influence of sex, gender, BMI and
morbid obesity on the GET of solid meals was verified by linear regression analysis.
Results Mean t(1/2) values of solid GET (± standard deviation) were 203.6 ± 76.0 min and 143.5 ± 19.1 min for lean and obese subjects,
respectively (P = 0.0010). Mean t(lag) values of solid GET were 127.3 ± 42.7 min and 98.4 ± 13.0 min for lean and obese subjects, respectively
(P = 0.0044). No significant difference in semi-solid GET was observed between the lean and morbidly obese groups.
Conclusion The present study demonstrated a significantly enhanced gastric emptying of the solid meal test in morbidly obese patients
when compared to lean subjects. This finding is compatible with the hypothesis that rapid gastric emptying in morbidly obese
subjects increases caloric intake due to a more rapid loss of satiety. 相似文献
70.
AIM: The aim of the study is to compare the results obtained using two different techniques of reconstruction after pancreaticoduodenectomy: pancreaticojejunostomy and pancreatic remnant duct occlusion. METHODS: The authors describe a retrospective study performed in 44 nonselected patients submitted to pancreaticoduodenectomy from 2000 to 2004. They have been divided into 2 groups. Patient characteristics were comparable in both groups. The first group (22 patients) received pancreaticojejunostomy. The second group (22 patients) received duct occlusion with sclerosing glue. Intraoperative finding (operative time, estimated blood loss) and postoperative morbidity and mortality were evaluated. Endocrine and exocrine function were analyzed at 3 and 12 months after surgery. RESULTS: Results showed no differences in median blood loss, duration operation and hospital day. Morbidity and mortality were higher in duct occlusion group; pancreatic fistula was more frequent after duct occlusion, but less dangerous than one from pancreaticojejeunostomy. Also exocrine function was better in anastomosis group and the incidence of diabetes mellitus was higher in patients with duct occlusion. CONCLUSION: Pacreaticojejunostomy is the procedure of choice, while duct occlusion should be performed in friable stump with small pancreatic duct (higher risk of pancreatic fistula). 相似文献