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排序方式: 共有190条查询结果,搜索用时 15 毫秒
1.
2.
Body composition in patients treated with peritoneal dialysis   总被引:2,自引:1,他引:1  
Background: Malnutrition is a common complication in uremia and during maintenance dialysis. Several factors contribute to its development. Different modes of dialysis treatment may differ in their effects on nutritional status. Methods: In order to analyse the nutritional consequences of peritoneal dialysis (PD), body composition analyses were performed in PD patients between February 1993 and March 1996. Body cell mass (BCM) was estimated from measurements of total body potassium (TBK) in a whole-body counter. Total body water (TBW) was determined by measurement of tritiated water. Body fat (BF) was calculated from body weight (BW), TBK and TBW. Observed values were related to predicted (o/p) derived from local population studies. Results: Sixty patients were repeatedly investigated during the study period. Of these, 34 were investigated during the first year of PD. At the start of dialysis, TBK o/p was 0.94 and BF o/p 0.76. No change in body composition was seen during the observation period in the group as a whole. However, within the group individual changes in BW were strongly correlated with individual changes in BF (r=0.66, P=0.0001). Twenty-six patients were examined during the second and third year of PD. In this group, BW o/p remained constant over time. However, there was a small but significant decline of TBK o/p and a concomitant increase of BF o/p (P<0.05). No correlation was observed between changes in TBK and changes in serum albumin. Conclusions: The results of this study indicate, that there may be a risk for further reduction of body cell mass during long-term PD treatment, while body energy stores are maintained or even increased.  相似文献   
3.

Objectives

Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.

Material and Methods

Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.

Results

Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).

Conclusions

The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats.  相似文献   
4.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
5.
6.
Modified Pulmonary Vein Isolation in AF Ablation. Introduction: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high‐frequency AF nests may have a higher efficacy. Methods and Results: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled. We compared the efficacy of a modified PVI (ablation line: 1.0–1.5 cm from the PV ostium with encircling the AF nests [spectral analysis with DF >70 Hz during SR, Group II]) versus the anatomy‐guided conventional PVI (Group I). In Group II, the DF value along the PV ostium was lower than 70 Hz after the PVI. The primary endpoint was the freedom from symptomatic atrial arrhythmias after a single procedure. We also followed the autonomic function by a time‐domain analysis of the heart rate variability. In both groups, AF nests were observed and electric isolation was successfully obtained in all patients. With a mean duration of 16 ± 6.1 months of follow‐up, Group II had a higher single procedure efficacy without drugs (78.7% vs 66.1%, log‐rank test: P = 0.02), and fewer repeat procedures (6.6% vs 23%; P = 0.04), as compared to Group I. Conclusion: PVI incorporating the high frequency AF nests adjacent to the PV ostia had a better single procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1155–1162, November 2012)  相似文献   
7.
应用5-氨基-γ-酮戊酸(ALA)诱导的卟啉荧光诊断(FDAP)中,肉眼可观察到原卟啉IX(PpIX)沉积。因操作重复性低,且涉及PpIX肿瘤选择的机制知之甚少,所以解释荧光数据仍有些困难。本研究中,作者要研究FDAP后银屑病和日光性角化病(AK)患者皮损的PpIX沉积情况。基于此目的,将患者脱屑区皮损和无皮损正常皮肤用20%ALA油孵育3h,进行FDAP,取强荧光区皮损和无皮损处皮肤活检。从活检标本中提取PpIX、蛋白质和双链DNA行荧光分光光度法定量,用图像分析软件分析由FDAP获得的数字图像。  相似文献   
8.
Daley  K.  B.  Wodrich  D.  L.  高蕊 《世界核心医学期刊文摘》2006,2(8):39-39
目的:观察评估通过使用胰岛素泵以稳定血糖,是否可以改善1型糖尿病患儿的课堂注意力。试验设计:对4例患有1型糖尿病且血糖水平不稳定的患儿在课堂中的表现进行为期10d的观察。在放置胰岛素泵,控制血糖后再观察10d。利用改良多基线设计血糖控制水平是否与患儿专注于功课和走神行  相似文献   
9.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored.  相似文献   
10.
BACKGROUND: Ximelagatran is an oral direct thrombin inhibitor currently in clinical development as an anticoagulant for the prevention and treatment of thromboembolic disease. After oral administration, ximelagatran is rapidly absorbed and bioconverted to its active form, melagatran. OBJECTIVE: To investigate the effect of severe renal impairment on the pharmacokinetics and pharmacodynamics of melagatran following administration of subcutaneous melagatran and oral ximelagatran. STUDY DESIGN: This was a nonblinded randomised crossover study with 2 study days, separated by a washout period of 1-3 weeks. Twelve volunteers with severe renal impairment and 12 controls with normal renal function were included, with median (range) glomerular filtration rates (GFR) of 13 (5-24) and 86 (70-105) mL/min, respectively. All volunteers received, in a randomised sequence, a 3mg subcutaneous injection of melagatran and a 24mg immediate-release tablet of ximelagatran. Blood samples were collected up to 12 and 14 hours after administration of the subcutaneous and oral doses, respectively, for determination of melagatran plasma concentrations and the activated partial thromboplastin time (APTT), an ex vivo measurement of coagulation time. Urine was collected for 24 hours after each dose for determination of melagatran concentration. RESULTS: For the volunteers with severe renal impairment, the area under the plasma concentration-time curve (AUC) and the half-life of melagatran were significantly higher than in the control group with normal renal function. Least-squares mean estimates of the ratios of the mean AUC for volunteers with severe renal impairment and controls (95% confidence intervals) were 4.03 (3.29-4.93) after subcutaneous melagatran and 5.33 (3.76-7.56) after oral ximelagatran. This result was related to the decreased renal clearance (CL(R)) of melagatran, which was linearly correlated with GFR. In the severe renal impairment and control groups, respectively, the mean CL(R) of melagatran was 12.5 and 81.3 mL/min after subcutaneous administration of melagatran and 14.3 and 107 mL/min after oral administration of ximelagatran. There was a nonlinear relationship between the APTT ratio (postdose/predose APTT value) and melagatran plasma concentration. A statistically significant higher slope of the concentration-effect relationship, described by linear regression of the APTT ratio versus the square root of melagatran plasma concentrations, was estimated for the group with severe renal impairment compared to the control group; however, the increase in slope was minor and the estimated differences in APTT ratio between the groups in the studied concentration range was less than 10% and not considered clincially relevant. Ximelagatran and melagatran were well tolerated in both groups. CONCLUSIONS: After administration of subcutaneous melagatran and oral ximelagatran, subjects with severe renal impairment had significantly higher melagatran exposure and longer half-life because of lower CL(R) of melagatran compared with the control group with normal renal function, suggesting that a decrease in dose and/or an increase in the administration interval in patients with severe renal impairment would be appropriate.  相似文献   
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