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131.
BACKGROUND/AIMS: Bile acids are synthesized in the liver and released into the intestinal tract to aid in digestion and absorption by increasing permeability via alteration of the cell membrane. Bedridden elderly patients typically have pressure ulcers that may be due to both physical local pressure as well as skin cell changes induced by the physiologic effects of bile acids. METHODOLOGY: This study investigated 31 elderly bedridden patients with pressure ulcers (mean age, 81.7 years) and 19 healthy elderly (mean age, 79.7 years). Five serum bile acid fractions were summed to determine total bile acid, and transaminase and cholesterol levels were also measured. RESULTS: Total cholesterol levels were significantly lower (p<0.05) in pressure ulcer patients and transaminase levels were not significantly different between the two groups. The primary bile acids were generally higher and the secondary and tertiary bile acids lower in pressure ulcer patients. In particular, the secondary bile acid deoxycholic acid was significantly higher in all pressure ulcer patients. When analyzed by grade of pressure ulcer, the primary bile acids were significantly lower in pressure ulcer patients. CONCLUSIONS: Secondary bile acid fraction deoxycholic acid measurements may indicate bedridden patients at higher risk for pressure ulcers.  相似文献   
132.
The purpose of this study was to investigate whether an association exists between the promoter region of the prostacyclin synthase gene and essential hypertension (EH). Using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method, we discovered a novel single nucleotide polymorphism (SNP), T-192G, in the 5'-flanking region. We performed an association study using the SNP in 200 patients and 200 controls. The allele frequency distribution in the two groups was not significantly different. Thus, this SNP in the PGIS gene is not associated with EH.  相似文献   
133.
BACKGROUND: Ventricular tachyarrhythmias (VT/VF) are 1 of the most important factors determining the prognosis of patients with heart failure (HF). Although priority is given to implantable cardioverter defibrillator (ICD) therapy for the prevention of sudden cardiac death, electrophysiologic-study (EPS)-guided preventive therapy could be important for reducing the number of cardiac events. METHODS AND RESULTS: Of 864 patients with a history of HF, an EPS was performed in 168 and 121 had inducible VT/VF. Under the basic therapy of an ICD, additional catheter ablation was attempted for 95 of 124 monomorphic VT foci in 74 patients, and 78 of the VT were successfully ablated. The prognoses were compared among 5 patient groups with different results for the EPS and catheter ablation: (1) success group (n=43), (2) failure group (n=15), (3) not attempted group (n=16), (4) VF group (n=47), and (5) no inducible VT/VF group. During a follow-up period of 31+/-22 months, the incidence of VT/VF was lower in the success and no inducible VT/VF groups than in the other groups (p=0.0018), although a significant difference was not observed for the total deaths. CONCLUSION: EPS-guided preventive therapy using an ICD and catheter ablation can be useful, at least for the reduction of arrhythmic events in patients with HF.  相似文献   
134.
In lead optimization, it is difficult to estimate when an analog series might be saturated and synthesis of additional compounds would be unlikely to yield further progress. Rather than terminating a series, one often continues to generate analogs hoping to reach the final optimization goal, even if obstacles that are faced ultimately prove to be unsurmountable. Clearly, methodologies to better understand series progression and saturation are highly desirable. However, only a few approaches are currently available to monitor series progression and aid in decision making. Herein, we introduce a new computational method to assess progression saturation of an analog series by relating the properties of existing compounds to those of synthetic candidates and comparing their distributions in chemical space. The neighborhoods of analogs are analyzed and the distance relationships between existing and candidate compounds quantified. An intuitive dual scoring scheme makes it possible to characterize analog series and their degree of progression saturation.

Chemical space view of an analog series. Shown are inactive (red) and active (blue) analogs together with virtual candidate compounds (green) available to expand the series. Chemical neighborhoods of analogs are depicted in gray.  相似文献   
135.
The aim of the present study was to determine and compare the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and their molecular characteristics among veterinary staff in Sapporo in 2008 and 2016. We isolated MRSA from veterinarians (Vet; n = 91), veterinary technicians (VT; n = 113), and other staff members (n = 24) from 45 small animal hospitals (animal hospitals), as well as from surface swabs (n = 123) obtained from 37 animal hospitals, in 2016. MRSA was observed in 14 Vets (15%), 7 VTs (6%), 2 other staff members (8%), and 6 environmental samples (5%). The prevalence of MRSA among veterinary staff tended to decrease, in comparison to 2008. All the MRSA isolates were classified as CC5/SCCmecII, which is commonly observed in medical settings in Japan. Upon performing pulse-field gel electrophoresis, with SmaI and EagI, and clfB sequence typing, it was observed that 16 of the MRSA isolates from 2016 were highly similar to those obtained in 2008. This suggests that some MRSA isolates persisted throughout 8 years, although their origins remain unclear. The continuation of education and monitoring of MRSA is necessary for the prevention and control of infection in these settings.  相似文献   
136.
In patients undergoing radiotherapy for localized prostate cancer, dose–volume histograms and clinical variables were examined to search for correlations between radiation treatment planning parameters and late rectal bleeding. We analyzed 129 patients with localized prostate cancer who were managed from 2002 to 2010 at our institution. They were treated with 3D conformal radiation therapy (3D-CRT, 70 Gy/35 fractions, 55 patients) or intensity-modulated radiation therapy (IMRT, 76 Gy/38 fractions, 74 patients). All radiation treatment plans were retrospectively reconstructed, dose–volume histograms of the rectum were generated, and the doses delivered to the rectum were calculated. Time to rectal bleeding ranged from 9–53 months, with a median of 18.7 months. Of the 129 patients, 33 patients had Grade 1 bleeding and were treated with steroid suppositories, while 25 patients with Grade 2 bleeding received argon plasma laser coagulation therapy (APC). Three patients with Grade 3 bleeding required both APC and blood transfusion. The 5-year incidence rate of Grade 2 or 3 rectal bleeding was 21.8% for the 3D-CRT group and 21.6% for the IMRT group. Univariate analysis showed significant differences in the average values from V65 to V10 between Grades 0–1 and Grades 2–3. Multivariate analysis demonstrated that patients with V65 ≥ 17% had a significantly increased risk (P = 0.032) of Grade 2 or 3 rectal bleeding. Of the 28 patients of Grade 2 or 3 rectal bleeding, 17 patients (60.7%) were cured by a single session of APC, while the other 11 patients required two sessions. Thus, none of the patients had any further rectal bleeding after the second APC session.  相似文献   
137.
138.
The effects of temperature and background counterions on ion-exchange selectivity for alkali metal ions and tetraalkylammonium ions on strongly acidic cation-exchange resins have been investigated using superheated water ion-exchange chromatography (SW-IEC). We have found out that alkali metal ions show reversal in the order of the distribution coefficient (KD), from Li+ < Na+ < K+ < Rb+ in water at ordinary temperature to Rb+ < K+ < Na+ < Li+ in superheated water, when a relatively large cation such as cesium ion is used as the background counterion. The effect of counterion on the ion-exchange selectivity is enhanced with the ion-exchange resins of higher ion-exchange capacity and cross-linking degree. Tetraalkylammonium ions chosen as model ions for poorly hydrated ions also exhibit reversal in the order of KD at around 430 K in superheated water. However, the effect of the nature of alkali metal counterions on the change in KD values of tetraalkylammonium ions is rather small compared with the effect on the KD of alkali metal ions. These results are attributed to the change in local hydration structures of the ions in the ion-exchange resin due to dehydration of alkali metal ions enhanced by interionic contacts of the analyte ion with the coexisting counterion and lower hydration energy of the ions at elevated temperatures. Although it has been considered that temperature is not effective at changing the ion-exchange separation selectivity, significant selectivity changes can be achieved by SW-IEC.

Metal ions in cation-exchange resins are dehydrated by interionic contacts with a co-existing counterion at elevated temperatures, which causes a drastic change in separation selectivity.  相似文献   
139.
Journal of Gastroenterology - Polymorphisms in the nucleotide diphosphate-linked moiety X-type motif 15 (NUDT15) gene are associated with thiopurine-induced leukopenia in patients with inflammatory...  相似文献   
140.
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