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91.
92.
Cerebral microbleeds (CMBs) are known to be associated with cognitive impairments in the elderly and in patients with various diseases; however, the nature of this association has not yet been evaluated in Parkinson’s disease (PD). In the present study, we analyzed the incidence of CMBs in PD according to cognitive status, and the impact of CMBs on cognitive performance was also evaluated. The CMBs in PD with dementia (n = 36), mild cognitive impairment (MCI, n = 46), or cognitively normal (n = 41) were analyzed using conventional T2*-weighted gradient-recalled echo images. Additionally, the relationship between the presence of CMBs and cognitive performance on individual tests of cognitive subdomains was analyzed using a detailed neuropsychological test. CMBs occurred more frequently in PD patients with dementia (36.1 %) compared to those with MCI (15.2 %), those who are cognitively normal (14.6 %), and normal controls (12.2 %, p = 0.025). However, the significant association of CMBs with PD dementia disappeared after adjusting white matter hyperintensities (WMHs) as a covariate. The frequencies of deep, lobar, and infratentorial CMBs did not differ among the four groups. After adjusting for age, sex, years of education, and WMHs, PD patients with CMBs had poorer performance in attention domain compared with those without CMBs (34.9 vs 42.6, p = 0.018). The present data demonstrate that even though CMBs were inseparably associated with the presence of WMHs, CMBs occur more commonly in PD patients with dementia than in those without dementia. Additionally, the burden of CMBs may contribute to further cognitive impairment in PD.  相似文献   
93.
Disgust is a prototypical type of negative affect. In animal models of excessive disgust, only a few brain sites are known in which localized dysfunction (lesions or neural inactivations) can induce intense ‘disgust reactions’ (e.g. gapes) to a normally pleasant sensation such as sweetness. Here, we aimed to map forebrain candidates more precisely, to identify where either local neuronal damage (excitotoxin lesions) or local pharmacological inactivation (muscimol/baclofen microinjections) caused rats to show excessive sensory disgust reactions to sucrose. Our study compared subregions of the nucleus accumbens shell, ventral pallidum, lateral hypothalamus, and adjacent extended amygdala. The results indicated that the posterior half of the ventral pallidum was the only forebrain site where intense sensory disgust gapes in response to sucrose were induced by both lesions and temporary inactivations (this site was previously identified as a hedonic hotspot for enhancements of sweetness ‘liking’). By comparison, for the nucleus accumbens, temporary GABA inactivations in the caudal half of the medial shell also generated sensory disgust, but lesions never did at any site. Furthermore, even inactivations failed to induce disgust in the rostral half of the accumbens shell (which also contains a hedonic hotspot). In other structures, neither lesions nor inactivations induced disgust as long as the posterior ventral pallidum remained spared. We conclude that the posterior ventral pallidum is an especially crucial hotspot for producing excessive sensory disgust by local pharmacological/lesion dysfunction. By comparison, the nucleus accumbens appears to segregate sites for pharmacological disgust induction and hedonic enhancement into separate posterior and rostral halves of the medial shell.  相似文献   
94.
95.

Purpose

Both rotational acetabular osteotomy (RAO) and eccentric rotational acetabular osteotomy (ERAO) are effective procedures for young patients with developmental dysplasia of the hip. However, no comparative study of biomechanical changes has been reported following these two procedures. We therefore explored the stress changes on femoral head after RAO and ERAO under different load conditions.

Materials and methods

Twelve female cadaveric hips without deformity were divided into RAO group and ERAO group. Stress value on femoral head was measured preoperatively and postoperatively after the vertical force was loaded on the cadaveric spine from 0 to 500 N. Stress change value was then calculated base on the measurements.

Results

In the RAO group, preoperative stress increased when loading on spine became larger, but postoperative stress changed its increasing trend into decreasing when the load was greater than 200 N (turning point). Same phenomenon was found in the ERAO group (turning point was 300 N). However, the difference between preoperative and postoperative stress was not statistically significant in both RAO and ERAO groups. Stress change value from each procedure showed similar trends. With the load growth, stress change increased firstly and then decreased, but the difference between RAO and ERAO was not statistically significant.

Conclusions

Both RAO and ERAO could correct the abnormal biomechanical effect of dysplastic hip; moreover, they may have similar biomechanical effects on femoral head, obtaining the same clinical outcomes. Non-biomechanical factors (surgical trauma, technical complexity, etc.) also play important roles in procedure selection.  相似文献   
96.
97.

Background

Septic shock is still related to unacceptably high morbidity and mortality. Microcirculatory alteration has been demonstrated to be one important reason associated with this evolution. Vasoactive drugs are often used to restore adequate arterial pressure and tissue perfusion in septic shock. To define the roles of different drugs, the effects of terlipressin (TP) on the microcirculation of small bowel mesentery in rats with endotoxic shock were evaluated and compared with those of norepinephrine (NE).

Methods

Twenty-five adult male Wistar rats were randomized to the control (n = 5), TP (n = 10), and NE (n = 10) groups. After endotoxic shock was induced by intravenous lipopolysaccharide administration for 30 min, rats in the NE and TP groups were infused with saline 5 mL/kg/h and simultaneously given NE 4 μg/kg/min or TP 8 μg/kg/h. The mean arterial pressure, heart rate, blood gas analysis, and microvascular blood flow images of small bowel mesentery were recorded.

Results

After fluid resuscitation and vasopressor infusion, the mean arterial pressure was restored to the baseline values in the NE and TP groups. In the TP group, the heart rate was significantly lower compared with the NE group (P = 0.013). The proportion of perfused vessels and the microvascular flow index (MFI) were significantly increased; furthermore, the heterogeneity index of small vessels was markedly decreased in both the interventional groups with respect to the control group. Compared with the NE group, the MFI was significantly higher (P < 0.05) and the heterogeneity index was significantly lower (P < 0.05) in the TP group.

Conclusions

Both TP and NE improved hemodynamic and microcirculatory alterations in rats with endotoxic shock. Compared with NE, TP was more effective in promoting MFI and improving the heterogeneity of small bowel mesentery in rats.  相似文献   
98.

Background

The incidence of alkaline reflux gastritis (ARG) after pancreaticoduodenectomy (PD) is high. Although Braun enteroenterostomy (BEE) may reduce ARG, BEE may result in marginal ulcers (MUs) due to the additional anastomotic stoma. We conducted this study to compare clinical outcomes of using a modified BEE (MBEE) with traditional gastrojejunostomy (TGJ), by inducting a purse-string suture instead of an additional anastomotic stoma.

Materials and methods

All 62 patients underwent standard PD at the Department of Hepatobiliopancreatic Surgery of West China Hospital between January 1, 2008 and January 31, 2012. Demographics, perioperative and postoperative factors, and follow-up morbidity were compared in those patients who underwent MBEE (n = 32, three patients were lost to follow-up) to those who underwent TGJ (n = 30, nine patients were lost to follow-up).

Results

Patients who underwent the MBEE experienced a decrease in total morbidity including ARG and MUs, relative to those who underwent TGJ (24.1% versus 58.3%, P = 0.011). With regard to the MBEE group, the total ARG rate was statistically significantly lower compared with the TGJ group (13.8% versus 37.5%, P = 0.046). In addition, the incidence of MUs was reduced.

Conclusions

In patients undergoing PD, the MBEE was safely performed with significantly more patients having reduced incidence of ARG and related sequela compared with those who underwent TGJ. These results support further study of patients undergoing gastroenterostomy after resection of the distal stomach in larger, randomized studies.  相似文献   
99.
100.

Objective

Switching antipsychotics is one useful therapeutic option when the treatment of schizophrenia encounters suboptimal efficacy and intolerability issues. This study aimed to investigate the efficacy and tolerability of cross-tapering switching to ziprasidone from other antipsychotics.

Methods

A total of 67 patients with schizophrenia or schizoaffective disorder were recruited in this 12-week, multicenter, non-comparative, open-label trial. Prior antipsychotics were allowed to be maintained for up to 4 weeks during the titration of ziprasidone. Efficacy was primarily measured using the 18-item Brief Psychotic Rating Scale (BPRS) at baseline, 4 weeks, 8 weeks, and 12 weeks. Efficacy was secondarily measured by the Clinical Global Impression-Severity (CGI-S) scale and the Global Assessment of Functioning (GAF) scale at each visit. Regarding the metabolic effects of switching to ziprasidone, weight, body mass index (BMI), waist-to-hip ratio (WHR), and lipid profile-including triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol levels-were measured at each follow-up visit.

Results

The BPRS scores were significantly improved at 12 weeks after switching to ziprasidone (F=5.96, df=2.11, p=0.003), whereas the CGI-S and GAF scores were not significantly changed. BMIs, WHRs, and TG levels were significantly decreased, with no significant changes in other lipid profiles.

Conclusion

Cross-tapering switching to ziprasidone is effective for patients with schizophrenia spectrum disorders. Beyond the efficacy of the procedure, favorable metabolic profiles show that switching to ziprasidone may be helpful for maintenance therapy over an extended period.  相似文献   
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