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81.
The effects of 0.15% quasi-steady-state end-tidal isoflurane on two saccadic eye-movement tests were examined in five volunteers using a newly devised computer-based recording system. The tests were saccadic latency and a countermanding task, the latter being an indicator of the highest levels of conscious performance. A moving light-emitting diode target was displayed on a screen and in the saccadic-latency task the latency of eye movement to the target was measured. In all five subjects the latency increased with anaesthetic by an amount which varied from 8 to 45 ms. This result was significantly different (p < 0.05) from subjects without anaesthetic. In the countermanding task, the subject had to voluntarily inhibit movement to the target. Again anaesthetic increased the latency of response, which varied from 6 to 33 ms. This result was significantly different (p < 0.05) from subjects without anaesthetic. In these studies it appeared that two tasks, one a simple latency test and the other, the countermanding task, requiring higher cortical processing were equally impaired at subanaesthetic concentrations of isoflurane.  相似文献   
82.
Urine contains several macromolecules that inhibit calcium oxalate (CaOx) crystallization. Among them is bikunin, the light chain of most of the inter-α-inhibitor (IαI) family of glycoproteins. This study aimed to verify whether bikunin and other members of the IαI family are synthesized in the kidneys or derived exclusively from the plasma. Proteins extracted from homogenized bovine kidney were applied successively to three chromatographic steps on DEAE-Sephacel, Sephacryl S-300, and Mono Q column. The inhibitory activity was assayed using a CaOx crystallization system. The presence of IαI-related proteins was determined by␣electrophoresis and Western blotting. The results showed that kidney extract contained a 125-kDa protein that cross-reacted with anti-IαI antibodies. This protein inhibited CaOx crystallization efficiently. According to its molecular weight and immunoreaction with anti-IαI antibody, the 125-kDa protein could be pre-α-inhibitor. The latter is known to encompass a heavy chain and bikunin, which may explain its inhibitory activity against CaOx crystallization. Consequently, we hypothesize that kidneys may produce some IαI-related proteins that are involved in the inhibition of stone formation. Received: 18 February 1998 / Accepted: 9 July 1998  相似文献   
83.
An extensive iodine deficiency disorders survery was conducted in Bangladesh in 1993 to assess the latest iodine nutriture status of the country. The clinical variables of the survey were goitre and cretinism, and the biochemical variable was urinary iodine. The “EPI-30 cluster” sampling methodology was followed for selecting the survey sites. In each survey site, the study population consisted of boys and girls, aged 5–11 years, and men and women, aged 15–44 years, in about equal populations. the total number of survey sites was 78 and the total number of respondents was 30 072. The total number of urine samples was 4512 (15% sub-sample). The current total goitre rate (grade 1+grade 2) in Bangladesh is 47.1% (hilly, 44.4%; flood-prone, 50.7%; and plains, 45.6%). The prevalence of cretinism in the country is 0.5% (hilly, 0.8%; flood-prone, 0.5%; and plains, 0.3%). Nearly 69% of Bangladeshi population have biochemical iodine deficiency (urinary iodine excretion [UIE]<10 mg/dl) (hilly, 84.4; flood-prone, 67.1%; and plains 60.4%). Women and children are more affected than men, in terms of both goitre prevalence and UIE. The widespread severe iodine deficiency in all ecological zones indicates that the country as a whole is an iodine-deficient region. Important recommendations of global interest are made from the experience of the survey. An erratum to this article is available at .  相似文献   
84.
Steroidogenesis-inducing protein (SIP) is a novel growth factor isolated from human ovarian follicular fluid. While the steroidogenic and mitogenic effects appear to be restricted towards gonadal cell types, we have recently demonstrated that SIP is also a potent mitogen for cell lines derived from ovarian surface epithelial carcinomas. Here, we demonstrate that SIP reverses hypoxia-induced cell proliferation arrest of the human ovarian carcinoma cell line SKA, as determined by flow cytometry and cell proliferation assays. Concomitant with this reversal of proliferation arrest is an increase in expression of cyclins D and E and a reduction in expression of the cyclin-dependent kinase inhibitor p27. Pretreatment of hypoxic SKA cells with SIP is also shown to increase Taxol sensitivity of these cells by two-fold. These studies further characterize the mitogenic activity of SIP at the molecular level and suggest that this protein may be an effective biological response modifier for ovarian carcinoma cells.  相似文献   
85.
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   
86.
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   
87.

Table of Contents

Contents Volume 32 No. 1 (2000) Section One: International Urology and Nephrology  相似文献   
88.
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   
89.
90.
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   
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