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Wild Norway rats were selected over 20 generations for reduced aggressiveness towards man. Selection for this characteristic was accompanied by many physiological changes. Although neophobia was significantly inhibited, and irritable aggression reduced by selection, no changes were revealed in mouse-killing behavior or in intermale aggression. The mean level of 5-hydroxyindole acetic acid in the hypothalamus as well as serotonin (5-HT) content in the hypothalamus, the midbrain and the cortices was higher in the 'domesticated' than in aggressive rats. Mean hypothalamic norepinephrine (NE) level also tended to be higher in the 'domesticated' animals. The resting corticosterone level and the response of the hypothalamic-pituitary-adrenocortical axis to an emotional stressor or intracerebroventricularly administered 5-HT or NE were decreased in domesticated rats compared to their aggressive counterparts. It is suggested that the diminution of the hypothalamic-pituitary-adrenocortical function as a result of selection for domesticated types of behavior depends, at least partly, on changes in brain monoaminergic systems.  相似文献   
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On the basis of new progressive anisotropic porous materials a mask with a recuperator which effectively heats the inhaled air by means of breathed-out air energy utilization has been created. The mask can decrease the load on human adaptation mechanism to unfavorable climatic effect of high latitudes where cold is a major unfavorable factor. Such a mask is a highly effective means of individual human protection from cold, providing the possibility to improve workers' labor conditions.  相似文献   
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BACKGROUND: Tubulointerstitial damage plays an important role in chronic kidney disease (CKD) with proteinuria. Urinary kidney injury molecule 1 (KIM-1) reflects tubular KIM-1 and is considered a sensitive biomarker for early tubular damage. We hypothesized that a decrease in proteinuria by using therapeutic interventions is associated with decreased urinary KIM-1 levels. STUDY DESIGN: Post hoc analysis of a randomized, double-blind, placebo-controlled, crossover trial. SETTING & PARTICIPANTS: 34 proteinuric patients without diabetes from our outpatient renal clinic. INTERVENTION: Stepwise 6-week interventions of losartan, sodium restriction (low-sodium [LS] diet), their combination, losartan plus hydrochlorothiazide (HCT), and the latter plus an LS diet. OUTCOMES & MEASUREMENTS: Urinary excretion of KIM-1, total protein, and N-acetyl-beta-d-glucosaminidase (NAG) as a positive control for tubular injury. RESULTS: Mean baseline urine protein level was 3.8 +/- 0.4 (SE) g/d, and KIM-1 level was 1,706 +/- 498 ng/d (increased compared with healthy controls; 74 ng/d). KIM-1 level was decreased by using placebo/LS (1,201 +/- 388 ng/d; P = 0.04), losartan/high sodium (1,184 +/- 296 ng/d; P = 0.09), losartan/LS (921 +/- 176 ng/d; P = 0.008), losartan/high sodium plus HCT (862 +/- 151 ng/d; P = 0.008) and losartan/LS plus HCT (743 +/- 170 ng/d; P = 0.001). The decrease in urinary KIM-1 levels paralleled the decrease in proteinuria (R = 0.523; P < 0.001), but not blood pressure or creatinine clearance. 16 patients reached target proteinuria with protein less than 1 g/d, whereas KIM-1 levels normalized in only 2 patients. Urinary NAG level was increased at baseline and significantly decreased during the treatment periods of combined losartan plus HCT only. The decrease in urinary NAG levels was not closely related to proteinuria. LIMITATIONS: Post hoc analysis. CONCLUSIONS: Urinary KIM-1 level was increased in patients with nondiabetic CKD with proteinuria and decreased in parallel with proteinuria by using losartan, sodium restriction, their combination, losartan plus HCT, and the latter plus sodium restriction. These results are consistent with the hypothesis of amelioration of proteinuria-induced tubular damage. Long-term studies are warranted to evaluate whether targeting treatment on KIM-1 can improve outcomes in patients with CKD with proteinuria.  相似文献   
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The study was carried out on Norway rats selected through more than 60 generations for high and low fear-induced aggressiveness towards humans (Institute of Cytology and Genetics). The intensity of aggressive behavior towards man, reflex startle response, and expression of serotonin transporter (5-HTT) gene were studied. Selection for high aggression was associated with more intense startle response. The expression of 5-HTT gene in the frontal cortex was reduced significantly in rats selected for high aggression to humans in comparison with nonaggressive rats. The authors conclude that 5-HTT is involved in the regulation of genetically determined fear-induced aggression. Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 147, No. 1, pp. 86-89, January, 2009  相似文献   
28.
To investigate the effect of Herpes Simplex virus (HSV) on spermatogenesis, HSV in ejaculate was detected by a rapid cultural method in 268 infertile males and 47 healthy ones. The number of mobile spermatozoa in HSV infected samples was less than in non-infected samples (21 mln/mlversus 40 mln/ml, p = 0.0001). The relative number of morphologically normal gametes was 13% versus 19% (p = 0.002), respectively. The quantitative karyological test discovered that males with HSV-infected ejaculate have more degenerating sex cells while in high virus contamination (more than 10 virus particles in 1 ml) the number of spermatides and spermatocytes of the 1 order at diploten stage is low. Organic testicular culture was used for more detailed study of pathogenetic mechanisms of HSV impact on spermatogenesis. Testicular explants infection was associated with reduction in the number of spermatogones, spermatocytes and spermatides on culturing week 2. The above findings reveal some pathogenetic mechanisms underling fertility disorders in males with HSV infection: a gametotoxic effect of the virus reducing populations of spermatogones, spermatocytes and spermatide; affected mobility and morphological characteristics of spermatozoa. Detection of the mechanisms of HSV action on spermatogenesis opens a perspective of antivirus drug administration in combined treatment of male infertility.  相似文献   
29.

Background

Vitreous substitutes presently in use for intraoperative tamponade are perfluorocarbon liquids (PFCL) and for post operative tamponade are silicon oil (SO), sulphur hexafluoride (SF6) and perfluorocarbon gas (PFC). Several factors are important for a thorough understanding of each of these vitreous substitutes. The absorption or necessity for removal, indications for use (including clinical studies and special surgical methods), additives and complications of use have to be considered.

Methods

Three port standard pars plana vitrectomy was performed in 60 consecutive cases requiring intra-vitreal intervention. PFCL was used intra-operatively in 30 cases (PFCL group and X group). The eyes were implanted with SO (silicon oil subgroup), PFC (C3F8 sub-group) and SF6 (SF6 sub-group) in twenty cases each. Apart from best corrected visual acuity (BCVA), the retinal status and the longevity of gas when used, changes and reaction in both the anterior and posterior segments were noted.

Result

The difference of postoperative BCVA in the PFCL and non-PFCL groups was statistically significant with p < 0.001. In both the PFCL and non-PFCL groups the difference between preoperative and postoperative BCVA was statistically significant with p < 0.0001. All three vitreous substitutes studied are effective given the case where they had been utilised.

Conclusion

PFCL is invaluable in the management of complicated retinal detachment (RD). Where a vitreous microsurgery is indicated, the visual outcome is good. SF6 is useful for short-term tamponade. Silicon oil and C3F8 are useful for longer tamponade.Key Words: Tamponade, Perfluorocarbon liquids, Silicon oil, Sulphur hexafluoride, Perfluorocarbon gas, Retinal detachment  相似文献   
30.
Congenital tuberculosis is a rare disease. The non-specific nature of presenting signs and symptoms (because of the lack of host response) and the fatal outcome in the absence of early therapy all underscore the importance of early diagnosis and treatment in infants. Recognition requires awareness that tuberculosis at this age has manifestations not found in older children. Here a case of congenital tuberculosis is presented, where changes were confined only to the thorax. Tuberculosis in the mother could be diagnosed only retrospectively.  相似文献   
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