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In narcotized rats, β-adrenoceptor blockers changed all parameters of heart rate variability indicating up-regulation of parasympathetic activity and down-regulation of the sympathetic one. In immobilized awake rats, the temporal and geometrical parameters varied similarly, while spectral analysis indicated possible activation of other neurohumoral mechanisms against the background of β-blocker treatment. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 144, No. 10, pp. 372–264, October, 2007  相似文献   
23.
Purpose

To compare the predictive roles of qualitative (PI-RADSv2) and quantitative assessment (ADC metrics), in differentiating Gleason pattern (GP) 3 + 4 from the more aggressive GP 4 + 3 prostate cancer (PCa) using radical prostatectomy (RP) specimen as the reference standard.

Methods

We retrospectively identified treatment-naïve peripheral (PZ) and transitional zone (TZ) Gleason Score 7 PCa patients who underwent multiparametric 3T prostate MRI (DWI with b value of 0,1400 and where unavailable, 0,500) and subsequent RP from 2011 to 2015. For each lesion identified on MRI, a PI-RADSv2 score was assigned by a radiologist blinded to pathology data. A PI-RADSv2 score ≤ 3 was defined as “low risk,” a PI-RADSv2 score ≥ 4 as “high risk” for clinically significant PCa. Mean tumor ADC (ADCT), ADC of adjacent normal tissue (ADCN), and ADCratio (ADCT/ADCN) were calculated. Stepwise regression analysis using tumor location, ADCT and ADCratio, b value, low vs. high PI-RADSv2 score was performed to differentiate GP 3 + 4 from 4 + 3.

Results

119 out of 645 cases initially identified met eligibility requirements. 76 lesions were GP 3 + 4, 43 were 4 + 3. ADCratio was significantly different between the two GP groups (p = 0.001). PI-RADSv2 score (“low” vs. “high”) was not significantly different between the two GP groups (p = 0.17). Regression analysis selected ADCT (p = 0.03) and ADCratio (p = 0.0007) as best predictors to differentiate GP 4 + 3 from 3 + 4. Estimated sensitivity, specificity, and accuracy of the predictive model in differentiating GP 4 + 3 from 3 + 4 were 37, 82, and 66%, respectively.

Conclusions

ADC metrics could differentiate GP 3 + 4 from 4 + 3 PCa with high specificity and moderate accuracy while PI-RADSv2, did not differentiate between these patterns.

  相似文献   
24.
Objective : to study the ulcer recurrence rate of Helicobacter pylori-positive duodenal ulcers at 1 yr after eradication of the bacteria by triple therapy. Method : Patients with H. pylori-positive duodenal ulcers were randomized to receive either triple therapy for 1 wk plus omeprazole for 4 wk (THple+OMP) (n = 78), or omeprazole alone (OMP) for 4 wk (N = 77). Patients were followed up every 3 months for symptom enquiry. At 1 yr, all asymptomatic patients were invited to attend for gastroscopy. Results : At 8 wk, 16 patients in the OMP group and four in the Triple+OMP group had an ulcer. During the 1-yr period, 12 patients in the OMP group and no patient in the Triple+OMP group developed symptomatic ulcers. At follow-up endoscopy at 1 yr, another 10 ulcers were detected in the OMP group and two in the Triple+OMP group. Fifteen patients in the OMP group and 13 in the Triple+OMP group were lost to follow-up. In total, ulcers were de-tected in 39 of 61 (64%) assessahle patients in the OMP group, and in six of 65 (97o) assessahle patients in the Triple+OMP group after I yr (χ2 test: p < 0.001). Of the patients whose H, pytori were successfully eradicated hy Triple+OMP at 8 wk, 90% remained H. pylori negative at 1 yr. Conclusion : Triple therapy for 1 wk eradicates H, pylori infection and significantly reduces duodenal ulcer relapses.  相似文献   
25.
The initial stages of nonischemic chronic heart failure in rats (model of oleothorax) were accompanied by the development of dyslipidemia. This state was characterized by an increase in total cholesterol concentration (due to the fraction of low-density lipoproteins) and atherogenicity index. The concentrations of plasma total cholesterol and low-density lipoproteins were shown to decrease in animals with severe course of nonischemic chronic heart failure. These changes were accompanied by a decrease in the atherogenicity index. Intragastric administration of cholesterol had little effect on the lipid composition of blood plasma in rats, irrespective of the severity of heart failure.  相似文献   
26.
Lenses from patients with glaucoma and senile cataract (control) were examined under electron microscope. Ultrastructural changes in the lenses of glaucoma patients differ from changes in senile cataract by a more pronounced thinning of the capsule and development of microdefects in it and in many cases by accumulation of amorphous material on the surface of the posterior capsule adjacent to the vitreous body. This material may be pseudo-exfoliate or a manifestation of stratification of the posterior capsule proper. Development of a pseudomembrane on the surface of posterior capsule is a manifestation of proliferative processes in glaucoma. These features in a certain measure reflect the mechanism of cataract development in glaucoma, which helps plan the measures for preventing it. The status of posterior lenticular capsule in glaucoma is to be taken into consideration when implanting intraocular lenses.  相似文献   
27.
An original method is proposed for treatment of long-standing intractable wounds and trophic ulcers using viable cryopreserved allodermotransplants and a distant air-plasma treatment. The main source of the allodermotransplants is the cadaverous skin. It was shown that the cadaverous skin taken during 17 hours after the donor's death was viable. The maximum period for storage of the viable skin when the worked out preservative is used at the temperature regimen -18 degrees C is 10 days, and at -70 degrees C it can be as long as 45 days. The analysis performed included 101 patients with long-standing intractable wounds and trophic ulcers. In 51 of them the new worked out method was used. An analysis of clinical and histomorphological data has proved that the application of the viable cryopreserved allodermotransplants and distant air-plasma treatment favor the better course of reparative processes. By the end of the forth week the wounds were completely closed in 19.7% of patients, the wound areas were considerably less (more than by 50% of the initial size) in 43.1%, less reduction of the wound area (less than 50% of the initial size) in 27.4%, in 9.8% there was no effect. No negative results were noted. It should be noted that closure of the tissue defect can be achieved by stimulation of the physiological regeneration of the patient's tissues. This method of regeneration of the skin is effective in trophic ulcers, long-standing intractable wounds and is also recommended in case of deficit of donor resources or when the severe state of the patient does not allow active surgical treatment.  相似文献   
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The study was concerned with comparison of carcinogenesis induced in the rat large intestine by 5 single doses of 1,2-dimethylhydrazine (DMH) 21 mg/kg injected at different circadian stages--either at 10 a.m. or 10 p.m. Evening injections were followed by significant decrease in incidence (from 91 to 75%) and size of tumor (27.2-15.5 mm2). Also, there were relatively fewer large tumors in the evening series.  相似文献   
30.
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