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91.
Following systemic administration of the noradrenaline (NA) neurotoxin, DSP4 (50 mg/kg), rats were found to be retarded in the rate at which they acquired the "right-turn" running response in a modified T-maze choice situation, as measured by the total number of errors per session and median latency to reach the goal box. Desipramine (DMI, 20 mg/kg), injected 30 min before DSP4 blocked the acquisition retardation. DSP4 was found to have a short-lasting effect upon spontaneous motor activity, while food and water intake recovery was complete within 7 days of the injection. Both the NA-accumulation data and endogenous NA concentrations indicated profound NA, but not 5-hydroxytryptamine (5-HT) and dopamine (DA), depletions in the cortex, hippocampus and cerebellum. These data seem to confirm the role of the locus coeruleus-noradrenaline (LC-NA) system in an instrumental learning situation.  相似文献   
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Effects of different concentrations of tetrakis--3,5-diisopropylsalicylatodiaquodicopper(II) (Cu(II)2(3,5-DIPS)4(H2O)2) on the reduced status of glutathione (GSH), the major nonprotein thiol in tissues, were investigated using freshly isolated hepatocytes. Cu(II)2(3,5-DIPS)4 below 100 M did not have any significant effects on either the GSH content or viability of the hepatocytes, but at 150–250 M it decreased both parameters after 1 h of incubation. The decrease in cellular GSH was not followed by an increase in the oxidized form of GSH (GSSG) in the cell suspension. The addition of deferoxamine with Cu(II)2(3,5-DIPS)4 to the hepatocyte suspension prevented depletion in GSH content and loss of cell viability by Cu(II)2(3,5-DIPS)4. Both GSH depletion and loss of cell viability were found to be Cu(II)2(3,5-DIPS)4 dose dependent. From these results, it appears that Cu(II)2(3,5-DIPS)4 penetrated the cell membrane and acted by decreasing the GSH level by forming a copper-glutathione complex.  相似文献   
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BACKGROUND: Prostasomes are membranous vesicles secreted by prostate gland, and they contain large amounts of cholesterol, sphingomyelin, calcium, and several enzymes. Prostasomes are involved in a number of biological functions. At ejaculation, these prostasomes are expelled with prostate secretions and are to be found in the seminal plasma as seminal prostasomes, which facilitate sperm function in various ways. METHODS: In this review, we discuss the structural and functional role of prostasomes, the various enzyme systems associated with these vesicles, and the biological role prostasomes play in male reproduction. RESULTS AND CONCLUSIONS Prostasomes are pluripotent and well-organized organelles secreted by the prostate gland. Prostasomes are ascribed to have many physiologiocal functions, the primary function being enhancement of sperm capacity. The several enzyme systems, small signaling molecules, and neuroendocrine markers associated with prostasomes reveal the complex nature of these vesicles in regulating sperm viability and vitality. The functional significance of these molecules that regulate complex pathways in these small vesicles is still a matter of dogma. Critical evaluation of the biological processes associated with prostasomes might be helpful in modeling new contraceptive agents, improving the techniques of in vitro fertilization, and in furthering our understanding and treatment of male factor infertility.  相似文献   
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Table of Contents

Contents Volume 32 No. 1 (2000) Section One: International Urology and Nephrology  相似文献   
97.
1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme…  相似文献   
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BACKGROUND: The recently discovered arachidonic acid derivatives, isoprostanes, are increased in pathological conditions associated with oxidative stress, such as diabetes. No role has yet been described for isoprostanes during the development of diabetic nephropathy. Cell culture in high ambient glucose has been used as a model in elucidating cellular mechanisms underlying diabetic nephropathy. Among the growth factors involved in the effect of high glucose, transforming growth factor-beta (TGF-beta) has been described as playing a key role in the development of nephropathy. METHODS: Streptozotocin-induced diabetic rats were supplemented in their diet with the antioxidant vitamin E (1000 U/kg diet). Blood and urine samples were taken to determine renal function and isoprostane concentration, as determined by gas chromatography/mass spectrometry. Glomerular mesangial and endothelial cells were cultured in high ambient glucose to determine the synthesis of isoprostanes and the role of isoprostanes in high glucose-induced synthesis of TGF-beta. RESULTS: Streptozotocin-induced diabetic rats had marked increases in plasma levels and urinary excretion rates of F(2)-isoprostanes. Dietary supplementation with vitamin E normalized (plasma) and reduced (urine) isoprostane levels and, surprisingly, improved proteinuria and blood urea nitrogen (BUN) levels. High ambient glucose increased F(2)-isoprostane synthesis in glomerular endothelial and mesangial cells in culture. Incubation of glomerular cells with F(2)-isoprostanes stimulated the production of TGF-beta. CONCLUSIONS: Increased F(2)-isoprostane synthesis during diabetes appears to be responsible in part for the increase in renal TGF-beta, a well-known mediator of diabetic nephropathy.  相似文献   
100.
Soft tissue surgery is more efficient, and sometimes more effective, using laser incisional surgery as opposed to standard techniques. The modern generation of lasers produces soft tissue incisions with a minimum amount of thermal damage at wound edges. The transition to laser incisional surgery requires a knowledge of methods, maneuvers, and safety information.  相似文献   
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