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This study aims to evaluate the effects of gamma-hydroxybutyrate (GHB) after spinal cord trauma (SCT). Twenty rabbits were divided equally into four groups: group I was the sham-operated group, group II suffered from SCT but received no treatment, group III was given a dose of 400 mg/kg of GHB intravenously before SCT and group IV received the same dose after SCT. Cerebrospinal fluid (CSF) samples were obtained 30 min before SCT (T(0)), at 60 (T(1)) and 120 min (T(2)) after SCT. There was a threefold increase in lactate levels from baseline value at T(2) in group II, while statistically significant elevation of the lactate levels were not observed in groups III and IV. Glucose levels at T(1) and T(2) were significantly lower in groups III and IV compared with the control group. The findings of this study demonstrate that GHB can control the increase of CSF lactate and glucose levels following SCT and that this metabolic effect may be associated with neuroprotective physiological changes.  相似文献   
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Summary In this study intra-arterial Endothelin-1 was applied to rabbit basilar arteries and morphological findings were compared between two groups who were either perfusion fixed or immersion fixed. We planned to establish the quantitative dimension of the drug-induced morphological alterations, independent of the fixation technique's effect.There was an abundance of collagenous fibres deposited among the smooth muscle cells which was not observed in control arteries and after immersion fixation. These degenerative changes are similar to the finding following subarachnoid haemorrhage. The only fixation-related difference was the fact that lamina elastica interna was not corrugated in the perfusion fixation group.It is concluded that, the observed changes in the connective tissue of the arterial wall alter the passive elastic properties and so affect the degree of the response to the vasoactive messengers.  相似文献   
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Influence of a self-etching primer on compound nerve action potentials   总被引:1,自引:0,他引:1  
The aim of this study was to evaluate the effect of self-etching primers on nerve conductance. A self-etching primer (One Up Bond F) which combines etching and bonding in one step, and a fifth-generation bonding agent (Prime&Bond NT ) were tested. Isolated rat sciatic nerves were placed between two platinum electrodes in a bath containing Tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials (CAP) were recorded before and after contact with the materials. One Up Bond F caused total inhibition of the CAP within an average time of 7 min. All CAPs in this group were blocked irreversibly. As with Prime&Bond NT, the reduction in CAP was 45.9% after an application time of 15 min, after which readings were terminated. Recovery of the CAP in this group were maintained after rinsing with fresh tyrode solution. One Up Bond F elicited faster blocking of nerve conductance under the conditions of this model. In the context of dentin desensitization with bonding agents, the self-etching primer may be more effective, clinically.  相似文献   
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Antioxidant capacity and nitric oxide in patients with hepatic cirrhosis   总被引:2,自引:0,他引:2  
This study investigated the relationship between the antioxidant capacity of blood and the serum level of nitric oxide (NO) in patients with hepatic cirrhosis. The study included 20 patients with compensated cirrhosis (group I), 30 with decompensated cirrhosis (group II), and 30 healthy controls (group III). The serum levels of NO, albumin, bilirubin, and uric acid, and the erythrocyte activity of superoxide dismutase (SOD) were measured in all groups. The mean erythrocyte SOD activity (5.94 +/- 3.21 U/mg protein) and serum NO level (25.19 +/- 8.15 micromol/L) in group I were similar to those of controls (6.86 +/- 2.47 U/mg protein and 21.67 +/- 6.51 micromol/L, respectively). However, erythrocyte SOD activity in group II was significantly lower than in groups I and III and mean serum NO level was significantly higher in group II than in groups I and III. In regard to non-enzymatic antioxidants, the mean serum albumin level was lower and the mean serum total bilirubin level was higher in group II than in groups I and III. As expected, group I had higher mean serum total bilirubin level than the control group. Correlation analysis showed that erythrocyte SOD activity in cirrhotic patients was negatively correlated with their serum levels of NO. These results suggest that disturbances of antioxidative mechanisms may diminish hepatic resistance to oxidative stress, thereby contributing to the development of fibrogenesis.  相似文献   
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International Urology and Nephrology - To evaluate the effect of masturbation on the spontaneous expulsion of distal ureteral stones 5–10 mm in size. A total of 128 men with distal...  相似文献   
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From November 3, 1975 to November 3, 1990, 874 kidney transplants were performed at our centers. Of these, 675 (77.2%) were from living donors and 199 (22.8%) were from cadaver donors. Five hundred eighty (66.4%) of the living donors were first degree related while 99 (11.3%) were unrelated or second degree related donors, 29 of which were spouses. All donor recipient pairs were ABO-compatible, with the exception of one pair. Donor recipient relations were wife to husband in 25 cases and husband to wife in 4 cases. All were first grafts and started functioning during surgery. In this series, the follow-up for the recipients was 4 to 64 months (mean 33.5 ± 4.5 months). One-year patient survival and graft survival rates were 92.4% and 81.9%, respectively. Two-year patient survival and graft survival rates were 92.4% and 78.2%, respectively. The single ABO-incompatible case is also doing well, 21 months postoperatively. This study demonstrates that the interspouse kidney transplantation may be used when cadaver organ shortage is a problem. While providing the couple with a better quality of life, interspouse kidney transplantation also enables the couple to share the joy of giving and receiving the gift of life from one another.
Resumen En nuestro centro se efectuaron 874 trasplantes renales entre noviembre 3 de 1975 y noviembre 3 de 1990; 675 (77.2%) fueron de donantes vivos y 199 (22.8%) de donantes cadavéricos; 580 (66.4%) de los donantes vivos fueron familiares de primer grado y 99 (11.3%) fueron donantes no relacionados familiarmente o familiares de segundo grado, de los cuales 29 eran cónyuges. Todas las parejas donante-recipiente exhibieron compatibilidad ABO, con excepción de una. La relación donante-recipiente fue esposa a esposo en 25 casos y esposo a esposa en 4 casos. Todos los injertos eran de primera vez y todos comenzaron a funcionar en la mesa de cirugía. El seguimiento osciló entre 4 y 64 meses (33.5 ± 4.5). Las tasas de sobrevida a un año del paciente y del injerto fueron 92.4% y 81.9% respectivamente; las tasas a dos años fueron 92.4% y 78.2% respectivamente. El único caso ABO no compatible también se encuentra bien, a 21 meses en la actualidad. El presente estudio demuestra que el trasplante renal entre esposos puede ser utilizado cuando haya escases de órganos cadavéricos. Al tiempo que permite una mejor calidad de vida, el procedimiento da a la pareja la oportunidad de gozar el hecho de otorgar y de recibir el regalo de la vida entre uno y otro.

Résumé Nous avons effectué 874 transplantations rénales dans nos centres de transplantation entre le 3 Nov, 1975 et le 3 Nov, 1990. Parmi celles-ci, 675 (77.2%) provenaient de donneurs vivants et 199 (22.8%) des reins provenaient de cadavres. Cinq cent quatre vingt des donneurs vivants (66.4%) étaient parents au premier degré alors que 99 (11.3%) étaient parents au 2è degré ou n'étaient pas parents, parmi lesquels 29 étaient des époux. Tous les couples donneur/receveur, sauf un, étaient compatibles dans le système ABO. Le couple donneur/receveur était femme à mari dans 25 cas et mari à femme dans quatre. Il s'agissait dans tous les cas d'une première greffe et qui a commencé à bien fonctionner sur la table d'opération. Dans cette série, le suivi des receveurs allait de 4 à 64 (33.5 ± 4.5) mois. Les taux de survie des malades et des greffes à un an étaient respectivement de 92.4% et 81.9%. Les taux de survie des malades et des greffes à deux ans étaient respectivement de 92.4% et 78.2%. Le seul cas avec incompatabilité ABO va très bien avec un recul de 21 mois. Cette étude montre que la transplantation entre époux est une solution valable en cas de manque de reins. En plus d'améliorer la qualité de survie du receveur et par là même du couple, cette variété de transplantation donne également au couple la possibilité d'avoir la joie de donner et de recevoir un cadeau de vie de leur époux.
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