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71.
Summary To examine the role of Ca channels in autoregulation of renal blood flow in response to changes of perfusion pressure, experiments were performed with perfused kidney in anesthetized dogs using a Ca channel activator, BAY K 8644, and vasoconstrictors such as noradrenaline and angiotensin II. Control observations usually showed excellent autoregulation of renal blood flow at pressures between 120 and 200 mm Hg, the autoregulatory index being less than 0.2. Verapamil (50 g/min, i.a. infusion) obviously inhibited the renal autoregulation. Simultaneous infusion of 5 g/min of BAY K 8644 with verapamil prevented both the increase of renal blood flow and the impairment of the autoregulation caused by verapamil. Whereas simultaneous infusion of noradrenaline (1 and 3 g/min) or angiotensin 11 (0.1 and 0.3 g/min) with verapamil dose-dependently reduced renal blood flow, these drugs could not antagonize the inhibitory effect of verapamil on autoregulation. The present experiments show that Ca channels play an important role in establishing renal autoregulation, and that a mere vasoconstriction by noradrenaline and angiotensin II is distinguished from autoregulatory performance.  相似文献   
72.
Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

  相似文献   
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Although participatory workplace improvement programs are known to provide favorable effects on high stress occupations like nursing, no studies have confirmed its effect using biomarkers. The aim of this study was to determine whether a participatory workplace improvement program would decrease stress-related symptoms as evaluated by biomarkers and self-reported stress among hospital nurses. Three actions to alleviate job stress, which were determined through focus group interviews and voting, were undertaken for two months. A total of 31 female Japanese nurses underwent measurement of inflammatory markers, autonomic nervous activity (ANA), and perceived job stress (PJS) at three-time points; before the program (T1), within a week after the completion of the program (T2), and three months after the program (T3). A series of inflammatory markers (Interferon-γ, Interleukin (IL)-6, and IL-12/23p40) decreased significantly at T2, and IL-12/23p40 and IL-15 significantly decreased at T3 compared to T1, while ANA and PJS remained unchanged. Our participatory program exerted beneficial effects in reducing inflammatory responses, but not for ANA and PJS. Further investigations with a better study design, i.e., a randomized controlled trial, and a larger sample size are warranted to determine what exerted beneficial effects on inflammatory markers and why other outcomes remained unchanged.  相似文献   
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The effects of enflurane (0.5%, 1.5% and 2.5%) on the excitation and inhibition of dorsal horn wide dynamic range (WDR) neuronal activity induced by bradykinin (BK) injection was studied in spinal cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind paw foot pads of decerebrate, spinal cord transected (L1–2) cats. When 10µg of BK was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus, 24 of 26 WDR neurons (92%) gave excitatory responses and 2 (8%) gave inhibitory resposes. On the other hand, when the injection of 10µg of BK into the femoral artery contralateral to the recording site was used as the noxious test stimulus, 7 of 12 WDR neurons (58%) gave inhibitory responses, 3 (25%) gave excitatory responses, and 2 (17%) showed no response. The excitatory neuronal activity in WDR neurons was not depressed by 0.5% or 1.5% enflurane but was depressed significantly by 2.5%. However, the inhibitory neuronal activity in WDR neurons was significantly depressed by 0.5%, 1.5% and 2.5% enflurane. We have found that enflurane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by BK injection. These results suggest that the reduction of excitatory and inhibitory responses produced by noxious stimulation is likely to be the fundamental basis of the enflurane-induced anesthetic state in terms of WDR neurons.(Nagasaka H, Nakajima T, Takano Y et al.: Enflurane reduces the excitation and inhibition of dosal horn WDR neuronal activity induced by BK injection in spinal cats. J Anesth 4: 102–109, 1990)  相似文献   
77.
Relatively large amounts of DOPA as compared with the concentration of norepinephrine are found in human dental pulp. AADC and COMT are localized in blood vessel walls of human dental pulp. This localization suggests a functional relationship between COMT and AADC with regard to the metabolism of DOPA.  相似文献   
78.
OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach cancer (SC).METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian, Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects..MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and SC cases (79.4%,P=0.0416), the increased risk had an adjusted OR of 1.79 (95?:1.01-3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intakeof meat, the carriers of the MTHFR C/T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their exposure level to environmental factors.  相似文献   
79.
80.
Background A possible association between Helicobacter pylori seropositivity and tumor necrosis factor (TNF) A G-308A has been reported in Korea. The present study examined the associations of H. pylori with functional polymorphisms, TNF-A G-308A, C-857T, and T-1031C, and TNF-B A252G in Japanese subjects.Methods The total of 1374 study subjects included 241 outpatients who participated in an H. pylori eradication program (HPE), 679 first-visit outpatients (FVO) at a regional cancer hospital, and 454 local residents who received a health checkup examination (HCE).Results The frequency of the TNF-A -308A allele was only 1.3% of 480 chromosomes in the HPE group, so the FVO and HCE groups were not genotyped for that polymorphism. The genotype frequency of TNF-A C-857T was 69.2% CC, 27.7% CT, and 3.1% TT; that of TNF-A T-1031C was 69.4% TT, 28.1% TC, and 2.5% CC; and that of TNF-B A252G was 36.8% AA, 48.2% AG, and 15.0% GG. TNF-A -857T was tightly linked to TNF-A -1031T and TNF-B 252A. No significant associations between H. pylori seropositivity and polymorphisms of TNF-A C-857T and TNF-B A252G were observed. However, a reduced odds ratio adjusted for sex, age, and recruitment source was observed for TNF-A -1031CC (0.43; 95% confidence interval, 0.20–0.91) relative to TNF-A -1031TT. Subjects with TNF-A -857CC and -1031CC showed the lowest seropositivity (38.2% of 34 participants), while those with TNF-A -857TT and -1031TT showed the highest (66.7% of 42 participants).Conclusions This study suggests that the possibly high expression genotype of TNF-A may increase susceptibility to persistent H. pylori infection.  相似文献   
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