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91.
OBJECTIVE: The purpose of this study was to investigate whether an inguinal hernia would have an impact on the testicular volume and blood flow by scrotal ultrasonography. METHODS: Twenty-six male patients with unilateral inguinal hernias with a mean age of 48.1 years were included in the study. Testicular volumes were calculated, and spectral parameters such as the pulsatility index and resistive index of the testicular artery at supratesticular, subcapsular, and intratesticular levels on both the side with the inguinal hernia and the contralateral side were measured by a preoperative ultrasonographic examination. Comparisons between the dependent groups were performed by a Wilcoxon or paired samples t test where appropriate. RESULTS: The mean +/- SD testicular volume on the side with the inguinal hernia was significantly higher than that on the contralateral testis (15.46+/-4.49 versus 14.54+/-3.65 mL, respectively; P<.05, Student t test). In addition, the mean resistive index of the intratesticular arteries was significantly higher on the side with the hernia compared with the contralateral side (0.66+/-0.06 versus 0.63+/-0.05; P<.05, Student t test). CONCLUSIONS: These data indicate that an inguinal hernia may impair testicular blood flow, which may be attributable to an intermittent mechanical compression effect on the funiculus spermaticus in the inguinal canal.  相似文献   
92.
The gut of the human neonate is colonized rapidly after birth from an early sparse and highly distinct microbiota to a more adult-like and convergent state, within 1 to 3 years. The progression of colonizing bacterial species is non-random. During the first months of life several shifts commonly occur in the species prevalent in our guts. Although the sequential progression of these species is remarkably consistent across individuals and geographies, there is inter-individual variation in the rate of progression. Our study and others suggest that the rate is influenced by environmental factors, and influences our future health. In this article, we review our recent contribution to cataloging the developing infant gut microbiota alongside other important recent studies. We suggest testable hypotheses that arise from this synthesis.  相似文献   
93.

Introduction

The incidence of accessory renal arteries is very high. Multidetector Computed Tomography (MDCT) is a minimally invasive alternative to conventional angiography in preoperative evaluation. The aim of this study was to document the incidence of accessory renal arteries and the level of origin of main renal arteries from abdominal aorta.

Methods

The study was conducted on one hundred patients in whom aortofemoropopliteal or aortic CT angiography was done for various indications at a tertiary care center in North India. CT angiography was performed on 64 slice MDCT scanner. The reconstructed images were analyzed using vessel analysis software.

Results

Accessory renal arteries were present in 36% cases with unilateral anomaly in 30% cases and bilateral in 6% cases. The dominant side of renal artery variations was the right side. All the accessory arteries took origin from the aorta and 52.8% of these supplied the inferior pole of the kidney. In 99% cases the origin of main renal artery was between upper border of L1 vertebra and lower border of L2 vertebra. The most common site of origin was at the level of intervertebral disc between L1 and L2.

Discussion

The incidence of multiple renal arteries is much higher than predicted by various studies. Comprehensive anatomic depiction of the renal arterial pattern aids in determining the technical feasibility of surgical and endourological interventions. It helps to avoid postoperative complications.  相似文献   
94.

Purpose

Hyperintensity along the ipsilateral cortical spinal tract (CST) on a diffusion weighted imaging (DWI) has been reported to may be associated with motor disability after brain infarction and can be misdiagnosed as a new infarction. However, the underlying patho-physiology related to this finding is not clear. The goal of our study was to analyze the diffusion tensor imaging (DTI) changes in patients with this hyperintensity.

Materials and methods

Eight patients (50 ± 10 years) who exhibited hyperintensity on DWI along ipsilateral CST from 3 to 21 days after stroke onset were reviewed as positive group, including 5 patients with serial DTI examinations. Twelve patients without hyperintensity during the matched examination time were classified as reference group. The apparent diffusion coefficient (ADC), fractional anisotropy (FA), and eigenvalues and their ratios (ipsilateral/contralateral value) in cerebral peduncle were measured, their correlation with motor function scale at eight months after stroke onset were evaluated.

Results

The serial examinations showed that hyperintensity could eventually disappear. Both the ipsilateral ADC and FA values were significantly decreased (p < 0.05) compared to the contralateral side. The ipsilateral FA significantly correlated with motor function scale in both groups (r = 0.875, 0.738; p = 0.004, 0.006 respectively).

Conclusions

The hyperintensity on DWI is a transient pathological process of Wallerian degeneration after ischemic stroke, its diffusion characteristics include concurrent significant decrease of ipsilateral ADC and FA. The ipsilateral FA value has the potential to predict neurological motor function outcome in such patients.  相似文献   
95.
96.
Previous literature has shown that sedentary older women rely on peripheral adaptations to improve cardiorespiratory fitness with endurance training i.e. they show minimal increases in central parameters (cardiac output, Q) in response to endurance training. The purpose of this study therefore was to determine whether endurance trained older women were able to preserve maximal exercise Q and were characterized by a high stroke volume (SV) when compared to physically inactive older women. Trained (n = 7) and untrained (n = 1 0) women attended two maximal and one submaximal laboratory session. Breath-by-breath analysis was conducted using mass spectrometry and Q was assessed using acetylene open circuit inert gas wash-in. Multivariate analysis of variance and paired samples t-tests were used to determine between and within group differences. Trained women had a significantly higher VO2max (37.5 vs. 24.1 ml-1·kg·min-1) compared to untrained women. There were no differences for peripheral oxygen extraction (VO2/Q) at either submaximal or maximal work rates; however trained women had a significantly higher SV at maximal (119.3 vs. 94.6 ml) exercise compared to untrained women. In both trained and untrained women, SV did not rise significantly between submaximal and maximal exercise. Conclusion: Highly fit, endurance trained older women are able to preserve central parameters of VO2max. Peripheral oxygen extraction is similar between older trained and untrained women.

Key points

  • Older women are able to preserve stroke volume with high volumes of endurance training.
  • Stroke volume of endurance trained older women does not continue to rise until maximal exercise, as is the case in young endurance trained adults.
  • Peripheral oxygen extraction does not differ between endurance trained and physically inactive older women.
Key words: cardiac output, aging, exercise, running, VO2max  相似文献   
97.
Hypoglycemia is a common complication of treatment of diabetes mellitus. The potential neurological complications of hypoglycemia as seizures and coma are well-recognized entities. A hypoglycemic episode is a risk factor for a patient with diabetes to have cardiovascular complications. Myocardial ischemia and infarction are known to occur in the setting of hypoglycemia. In view of the potential association of the two, the diabetic patients should undergo a routine ECG in such circumstances.  相似文献   
98.
Objectives : To study the significance of cholecystitislike presentation and increased gallbladder wall thickness (GBWT) in patients with acute viral hepatitis (AVH). Methods : Sixty-seven consecutive patients with acute viral hepatitis (hepatitis A:3, hepatitis B:13, and enterically transmitted non-A, non-B hepatitis: 51) were included in this prospective study. Clinical assessment and sonographic evaluation of the GBWT were carried out every week until recovery from acute hepatitis. Results : The clinical presentation in 16 patients with hepatitis A and B and in 29 patients with enlerically transmitted non-A, non-B hepatitis (ET-NANB hepatitis) was typical of AVH, and the mean GBWT in these patients was 6.16 ± 2.23 mm and 7.28 ± 2.93 mm, respectively. The remaining 22 patients with ET-NANB hepatitis presented with features suggestive of acute cholecystitis (fever, severe pain, and tenderness right hypoehondrium), and the mean GBWT in these patients (10.18 ± 2.58 mm) was significantly higher compared with the rest of the patients with AVH ( p < 0.001). The mean GBWT in patients with AVH (7.31 ± 0.97 mm) was significantly higher compared with controls (1.76 ± 2.17 mm) ( p < 0.001). All patients with acute cholecystitis-like presentation recovered with conservative medical management. A time-dependent normalization of the thickened gallbladder wall was observed in all the patients within 6 wk. Conclusion : A proportion of our patients with ET-NANB hepatitis presented with acute cholecystitislike picture and had markedly thickened gallbladder wall on ultrasonography. These patients made an uneventful recovery, and the sonographic abnormalities disappeared within 6 wk.  相似文献   
99.
Dogra G  Rich L  Stanton K  Watts GF 《Diabetologia》2001,44(5):593-601
Aims/hypothesis. We examined whether endothelial function is impaired in patients with Type I (insulin-dependent) diabetes mellitus under conditions of near-normoglycaemia compared with age-matched healthy control subjects. Our aim was to determine whether microalbuminuria is associated with endothelial dysfunction in Type I diabetes. Methods. Endothelial function, measured as post-ischaemic flow-mediated dilatation of the brachial artery using ultrasound, was compared among 17 microalbuminuric and 17 normoalbuminuric diabetic patients, and 17 control subjects. Glyceryl trinitrate-mediated dilatation of the brachial artery was used to measure endothelium-independent function. All diabetic patients were studied at near-normoglycaemia, using insulin and 5 % dextrose infusions to maintain blood glucose between 3.5 and 8.0 mmol/l. Results. Flow-mediated dilatation was significantly lower in microalbuminuric diabetic patients (3.2 ± 0.3 %) compared with normoalbuminuric diabetic patients (5.4 ± 0.6 %) and control subjects (7.9 ± 0.6 %, p < 0.001). Normoalbuminuric diabetic patients also had significantly lower flow-mediated dilatation than control subjects (p = 0.01). Glyceryl trinitrate mediated dilatation was significantly lower in the microalbuminuric patients compared with the control subjects (11.9 ± 1.1 % vs 20.0 ± 1.2 %, p = 0.001). Albumin excretion rate and glycated haemoglobin showed a significant negative independent correlation with flow-mediated dilatation (both p < 0.05). Conclusion/interpretation. Type I diabetic patients show endothelial dysfunction at near-normoglycaemia compared with the control subjects, and this abnormality is more marked in diabetic patients with microalbuminuria. Endothelial dysfunction in Type I diabetes is related to the albumin excretion rate and glycaemic control. The presence of endothelial dysfunction in normoalbuminuric diabetic patients suggests it could precede microalbuminuria as an early risk marker for cardiovascular disease. [Diabetologia (2001) 44: 593–601] Received: 6 November 2000 and in revised form: 11 January 2001  相似文献   
100.
AIMS: Identification of implantable cardioverter/defibrillator (ICD) recipients at higher risk of future therapies may assist in pre-empting future shocks. Native QRS duration is an established predictor of overall mortality, but the role of this parameter as a clinical predictor of arrhythmic events warrants further investigation. METHODS AND RESULTS: In an analysis of a single-centre, 13-year ICD implantation experience (1990-2002), multiple clinical parameters including QRS duration were analysed using a multiple logistic regression model. Of 562 patients followed for at least 1 year, 98 (17%) did not receive ICD therapies (event-free, group A). Comparisons were made with a randomly selected sample of 123 patients who received ICD therapies (arrhythmic events, group B). There were no significant differences in age, gender, frequency of coronary artery disease, and degree of left ventricular dysfunction. However, QRS duration was a significant determinant of arrhythmic events (> or =100 vs. <100 ms: adjusted OR 2.75, 95% CI 1.37-5.51; > or =120 vs. <120 ms: adjusted OR 1.77, 95% CI 0.97-3.23). QRS duration was also a predictor of overall mortality in the logistic regression models (> or =100 ms: adjusted OR 3.72, 95% CI 1.17-11.9; > or =120 ms: adjusted OR 3.09, 95% CI 1.39-6.85). CONCLUSION: In this ICD population, consisting largely of secondary prevention ICD recipients, longer QRS duration predicted higher likelihood of arrhythmic events. Extent of QRS prolongation could guide the decision to initiate prophylactic anti-arrhythmic therapy in ICD patients.  相似文献   
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