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91.
92.
We performed a combined neurochemical and behavioral study to determine the effects of 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1-BnTIQ) on the extracellular dopamine concentrations in the striatum. Single dose administration of 1-BnTIQ (20, 40, and 80 mg/kg i.p.) increased striatal dopamine extracellular levels in a dose-dependent manner when an in vivo microdialysis technique was used to assess dopamine levels in the striatum of rats. Enhancement of striatal dopamine levels by systemic administration of a single dose of 1-BnTIQ was suppressed by perfusion of tetrodotoxin and a calcium ion-free solution into the striatum. This 1-BnTIQ-induced increase in extracellular dopamine concentration was also inhibited by pre-treatment with a dopamine uptake inhibitor, GBR12909 (1-(2-[bis(4-Fluorophenyl)-4-(3-phenylpropyl)piperazine dihydrochloride). Local application of 1-BnTIQ into the striatum via a dialysis probe failed to enhance the extracellular concentration of dopamine. However, microinjection of 1-BnTIQ into the substantia nigra pars compacta increased the extracellular dopamine levels in the striatum. Locomotor activity was increased by systemic administration of a single dose of 1-BnTIQ in a dose-dependent manner. This 1-BnTIQ-induced locomotor activity was attenuated by pre-treatment with SCH23390 (R(+)-7-Chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochlodride) and raclopride, D1 and D2 dopaminergic receptor antagonists, respectively. Moreover, 1-BnTIQ induced ipsilateral rotational behavior in 6-hydroxydopamine–lesioned rats. These results suggest that systemic administration of a single dose of 1-BnTIQ increases striatal extracellular dopamine concentration through activation of dopaminergic nigra striatal neurons via the dopamine transporter.  相似文献   
93.
Background. Metabolic disturbances such as anoxia and hypoglycaemia are important in causing maldevelopment of the neonatal brain. While there have been some pathology studies of the effects of neonatal hypoglycaemia on brain development, reports of MRI findings in such infants have been rare. Objectives. To describe the MRI findings in neurologically handicapped children who had suffered from neonatal hypoglycaemia and to evaluate the relationship between the neurological impairment and neonatal hypoglycaemia. Materials and methods. We retrospectively evaluated the MRI findings in eight full-term infants with neonatal symptomatic hypoglycaemia who later exhibited neurological handicap. The age at which the MRI scans were obtained ranged from 9 months to 8 years 10 months (mean 4 years 1 month, median 4 years). Results. The most striking findings were prolonged T1 weighting and T2 weighting in the parieto-occipital periventricular deep white matter in six patients, suggesting abnormal or delayed myelination. Dilatation of the lateral ventricles, especially of the trigones, was observed in five patients in whom the distance between the posterior horns of the lateral ventricles and the adjacent sulci was reduced. The volume of white matter relative to grey matter was reduced in two patients. In addition, four patients exhibited cerebral cortical atrophy, mainly in the occipital lobe. Conclusions. These findings suggest that neonatal hypoglycaemia may cause delayed or abnormal myelination, especially in the parieto-occipital, periventricular, deep white matter, and may cause cerebral cortical atrophy, especially in the occipital lobe. Received: 1 August 1997 Accepted: 15 June 1998  相似文献   
94.
Carrageenin-induced paw edema in HMW- and LMW-kininogens-deficient rats was significantly less than that in normal rats. There are three kininogens, HMW-, LMW- and T-kininogens, in normal rat plasma, but B/N-Katholiek rat plasma contains only T-kininogen. The pretreatment with captopril, a kiniase II inhibitor, enhanced paw swelling of normal rats, but not that of the deficient rats, indicating that bradykinin released from HMW-kininogen may have a role for the swelling but T-kinin may not be released in this inflammation.  相似文献   
95.
Effect of 50% ethanolic extract of unripe fruits of Citrus unshiu (CU-ext) on type IV allergic reaction was examined by inhibitory activity of ear swelling of picryl chloride-induced contact dermatitis (PC-CD) in mice. Oral administration of CU-ext and subcutaneous administration of prednisolone showed inhibition of ear swelling during both induction and effector phases of PC-CD. The inhibitory activities of combinations of CU-ext (p.o.) and prednisolone (s.c.) during induction phase of PC-CD were more potent than those of CU-ext alone and prednisolone alone. Successive oral administration of hesperidin, a major flavanone glycoside of CU-ext, inhibited ear swelling during induction phase of PC-CD. The inhibitory activities of combinations of hesperidin (p.o.) and prednisolone (s.c.) were more potent than those of hesperidin alone and prednisolone alone. These results indicated that the combinations of prednisolone and CU-ext or hesperidin exerted a synergistic effect.  相似文献   
96.
BACKGROUND: Although thiopurines have a proven role in maintenance therapy for Crohn's disease, an alternative therapy is needed for patients intolerant or resistant to thiopurines. AIM: To evaluate the effectiveness of home enteral nutrition as a maintenance therapy regimen in which half of the daily calorie requirement is provided by an elemental diet and the remaining half by a free diet. We refer to this home enteral nutrition therapy as 'half elemental diet'. METHODS: Between 2002 and 2005, 51 patients in remission from two hospitals were randomly assigned to a half elemental diet group (n = 26) or a free diet group (n = 25). The primary outcome measure of this study was the occurrence of relapse over the 2-year period. RESULTS: The relapse rate in the half elemental diet group was significantly lower [34.6% vs. 64.0%; multivariate hazard ratio 0.40 (95% CI: 0.16-0.98)] than that in the free diet group after a mean follow-up of 11.9 months. Compliance was similar in the two groups. No adverse event occurred in any of the patients throughout the study. CONCLUSION: This randomized-controlled trial shows the effectiveness of an half elemental diet, which is a promising maintenance therapy for Crohn's disease patients.  相似文献   
97.

Background

No definitive evidence exists regarding use of adjuvant chemotherapy (AC) for high-risk cases after radical nephroureterectomy (RNU), and the benefit of AC remains controversial. The aims of this study were to evaluate the efficacy of AC in patients with upper tract urothelial carcinoma (UTUC) and to determine those who qualified for AC.

Patients and Methods

From 1990 to 2015, 449 patients with nonmetastatic UTUC underwent RNU at 6 Kitasato University-affiliated hospitals. Eight patients who received neoadjuvant chemotherapy were excluded from this study. One hundred patients (23%) received platinum-based AC for a median of 3 courses. Disease-free survival and cancer-specific survival (CSS) were estimated using the Kaplan–Meier method. Multivariate analyses were performed with the Cox proportional hazards regression model, controlling for the effects of clinicopathological factors.

Results

The median age was 69 years, and the median follow-up period was 35.7 months. In multivariate analyses, factors independently predictive of poorer survival included pT stage (≥pT3), lymph node status (pN+), tumor grade (Grade 3), lymphovascular invasion, and soft tissue surgical margin. For the risk stratification model, patients were categorized into 3 groups on the basis of these 5 risk factors. In the high-risk group (at least 3 risk factors, 83 patients), 41 patients (49%) were treated with AC, and the 5-year CSS rate was higher in the AC group compared with the non-AC group (P = .02).

Conclusion

Having more than 3 risk factors defined the high-risk group among UTUC patients after RNU. AC was associated with improved CSS in patients with high-risk UTUC.  相似文献   
98.
Hemodynamics in the prone jackknife position during surgery   总被引:1,自引:0,他引:1  
We examined the hemodynamic changes occurring with prone jackknife positioning during colorectal surgery. The operative procedure was restorative proctocolectomy with ileal J-pouch anal anastomosis in five patients with adenomatosis coli and six patients with ulcerative colitis and anoabdominal resection of the rectum with colonic J-pouch anal anastomosis in eight patients with rectal cancer. Nineteen patients (10 men and 9 women aged 41 +/- 19 years) were monitored with arterial and Swan-Ganz catheters during positioning. Measurements were obtained in the supine and prone positions (1 minute, 3 minutes), and the jackknife position (1, 3, 5, and 10 minutes), as well as before and after adoption of the Lloyd-Davies position (1, 3, 5, and 10 minutes). Turning the patient from the supine position to the prone position resulted in a significant decrease in the cardiac index (CI). However, following head-down rotation, the CI increased and returned to the value seen in the supine position (p less than 0.05). Heart rate (HR) slowed and mean arterial pressure (MAP) increased in the prone jackknife position. We concluded that the extent of the changes in cardiac function presented no serious problems.  相似文献   
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