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81.
Spatial Learning Deficits in Mice with a Targeted Glucocorticoid Receptor Gene Disruption 总被引:5,自引:0,他引:5
Melly S. Oitzl E. Ron de Kloet Marian Joëls Wolfgang Schmid Timothy J. Cole 《The European journal of neuroscience》1997,9(11):2284-2296
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor. 相似文献
82.
①目的探讨直肠内脱垂的有效治疗方法。②方法对11例直肠内脱垂的病人行吻合器痔上黏膜环切术(PPH),术后随访1~12个月。③结果全部病人术后均排便通畅,排便时间明显缩短,无明显手术并发症。④结论PPH治疗直肠内脱垂,手术操作简便、安全、疗效可靠,病人痛苦小、恢复快、并发症少,是一种值得推广的治疗方法。 相似文献
83.
本文就115例腹会阴直肠切除术,对会阴伤口的两种不同处理方法进行分析比较.在年龄、性别、病理分期及恶性程度无明显差异的情况下,会阴伤口一期缝合组的平均愈合时间为16.90±4.35天,伤口敞开组为37.04±15.44天,差异显著(P<0.002).术后局部复发率分别为3/69例和2/46例,均为4.35%(P>0.05).一期缝合组的平均住院费用约为敞开组的46.87%~76.52%.作者指出,鉴于直肠癌逆行向下的淋巴扩散极为罕见,仅发生于高恶性或伴广泛淋巴转移的病例,因而对癌肿远端需切除2cm~3cm正常肠管而同时切除肛直肠环、不得不作手术者,会阴部清除范围无需太大,会阴伤口可分层完全缝合;对位于肛管内或侵及肛直肠环的癌肿,须彻底清除坐骨直肠窝脂肪结缔组织.本文两组术后局部复发率无差异,进一步表明这一认识的正确性.本组结果充分表明了会阴伤口一期缝合法的合理性与可行性. 相似文献
84.
A Single-Blind, Crossover Comparison of the Pharmacokinetics and Cognitive Effects of a New Diazepam Rectal Gel with Intravenous Diazepam 总被引:3,自引:1,他引:2
Summary: Purpose: The objective of this study was to compare the pharmacokinetics and cognitive effects of a new diazepam (DZP) rectal gel (Diastat®) with intravenously administered DZP.
Methods: Twenty healthy volunteers were enrolled in a single-blind, randomized, double-dummy, two-period, crossover study. Subjects received either 15 mg of DZP rectal gel or 7.5 mg of DZP by intravenous infusion. Blood samples for DZP and desmethyldiazepam analysis were obtained before the dose and from 3 min to 240 h after the dose. Heart rate and blood pressure were measured over the first 24-h period. Subjects also completed five repetitions of a neuropsychological test battery over the first 8-h period.
Results: Diazepam rapidly appeared in plasma after rectal administration, exceeding 200 ng/mL within 15 min and reaching an initial maximum of 373 ng/ml at 45 min and a second maximum of 447 ± 91.1 ng/ml at ∼70 min. The absolute bioavailability of DZP rectal gel was 90.4%. Subjects receiving intravenous DZP were less alert and performed less efficiently on the WAIS Digit Symbol test 6 min after the dose. Subjects receiving DZP rectal gel performed less well on the WAIS Digit Span test 1 h after the dose and required more time to complete the Letter Cancellation and Grooved Pegboard tests 1 and 2 h after drug administration.
Conclusions: Diastat® displayed rapid, consistent absorption and was well tolerated. Alterations in cognition were mild and dissipated within 4 h of drug administration. This new rectal drug-delivery system offers an easy, safe, and bioavailable method to administer DZP. 相似文献
Methods: Twenty healthy volunteers were enrolled in a single-blind, randomized, double-dummy, two-period, crossover study. Subjects received either 15 mg of DZP rectal gel or 7.5 mg of DZP by intravenous infusion. Blood samples for DZP and desmethyldiazepam analysis were obtained before the dose and from 3 min to 240 h after the dose. Heart rate and blood pressure were measured over the first 24-h period. Subjects also completed five repetitions of a neuropsychological test battery over the first 8-h period.
Results: Diazepam rapidly appeared in plasma after rectal administration, exceeding 200 ng/mL within 15 min and reaching an initial maximum of 373 ng/ml at 45 min and a second maximum of 447 ± 91.1 ng/ml at ∼70 min. The absolute bioavailability of DZP rectal gel was 90.4%. Subjects receiving intravenous DZP were less alert and performed less efficiently on the WAIS Digit Symbol test 6 min after the dose. Subjects receiving DZP rectal gel performed less well on the WAIS Digit Span test 1 h after the dose and required more time to complete the Letter Cancellation and Grooved Pegboard tests 1 and 2 h after drug administration.
Conclusions: Diastat® displayed rapid, consistent absorption and was well tolerated. Alterations in cognition were mild and dissipated within 4 h of drug administration. This new rectal drug-delivery system offers an easy, safe, and bioavailable method to administer DZP. 相似文献
85.
Long-term result and current status of the Lichtenstein open tension-free hernioplasty 总被引:12,自引:6,他引:6
Summary The tension-free hernioplasty project began in 1984 at the Lichtenstein Hernia Institute. The method consists of complete reinforcement of the inguinal floor with a large sheet of mesh, with adequate mesh tissue interface beyond the boundary of the inguinal floor and creation of a new internal ring made of prosthesis. The preliminary report of this operation was published in 1989, with no recurrence at that point in time. Shortly after the submission of the report, several recurrences were encountered. Based on the lesson learned from those recurrences, the operation was slightly modified and reported in 1991 [Amid 1993]. Since then, the Lichtenstein technique has gained world-wide popularity. Outcome measures identical to ours and other authors have been achieved by even those surgeons who have no special interest or expertise in herniology. The purpose of this article is to report the current state of the open tension-free hernioplasty for the repair of primary and recurrent inguinal hernias. 相似文献
86.
可同化有机碳(AOC)是一项新的水质检测指标,通过它可以评估供水系统的水中是否有足够的营养物质可使微生物再生长。由于目前尚无可行的化学方法检测 AOC,因此主要是用各种生物方法加以检测。本文介绍用荧光假单胞菌 P—17菌株和螺菌属 NOX 菌株作为测试菌,通过定量观察其在水样中的生长,如从接种到生长至最大数量,以考察其利用水中营养物质的情况,进而推算出水中 AOC 的浓度。 相似文献
87.
Robert K. McNamara R. Duncan Kirkby Gregory E. dePape Ronald W. Skelton Michael E. Corcoran 《Hippocampus》1993,3(2):149-152
There is some controversy about the role of long-term potentiation (LTP) in spatial learning. The authors have found that triggering generalized kindled seizures with stimulation of the perforant path disrupts spatial learning in the Morris water maze but that kindling per se does not affect spatial learning. It is suggested that abnormal electrical activity induced by high-frequency stimulation of the perforant path may have been responsible for the disruption of spatial learning previously attributed to LTP saturation. 相似文献
88.
J. L. Beal M. Freysz G. Berthelon P. D’Athis S. Briet M. Wilkening 《Journal canadien d'anesthésie》1989,36(3):278-282
This prospective and randomized study compared the consequences of two irrigating fluids, distilled water and glycine for
transurethral prostatectomy. Forty-nine consecutive unselected patients undergoing transurethral resection of the prostate
with spinal anaesthesia were investigated. The irrigating fluid was either distilled water (group A, 24 patients) or glycine
1.5 per cent (group B, 25 patients). The absorption of irrigating fluid was measured, all surgical events and any clinical
signs of TURP syndrome during and after surgery were recorded. Early signs of TURP syndrome were observed in one patient in
group A and in four in group B without further consequence. From all the biological variables, only plasma protein concentration,
haematocrit, free plasma haemoglobin and free bilirubin concentrations were found to have changed. Plasma protein concentration
and haematocrit decreased significantly during and after surgery in the two groups. Free plasma haemoglobin increased significantly
with time: a significantly higher concentration was observed in group A than group B. Free bilirubin concentration increased
with time in the two groups and was statistically greater in group A. With the two irrigating fluids, we observed a significant
amount of haemolysis and haemodilution without clinical consequences. A low irrigating fluid pressure, a short resection time,
and the use of spinal anaesthesia seems to us to be essential. Close observation of patients following transurethral prostatectomy
is needed but the choice of the irrigating fluid does not seem to be important.
Cette étude prospective et randomisée a comparé les conséquences de deux liquides d’irrigation, l’eau distillée et le glycocolle
au cours de la chirurgie prostatique par voie basse. Quarante-neuf patients consécutifs, non sélectionnés, bénéficiant d’une
résection transuréthrale de prostate sous rachianesthésie, sont étudiés. Le liquide d’irrigation est soil l’eau distillée
(groupe A, 24 patients), soit le glycocolle à 1.5 pour cent (groupe B, 25 patients). L’absorption des liquides d’irrigation,
les incidents chirurgicaux et les signes cliniques du syndrome de réabsorption sont systématiquement notés. Des signes caractéristiques
du syndrome de réabsorption sont observés dans un cas dans le groupe A et dans quatre cos dans le groupe B sans conséquence
ultérieure. Seuls la protidémie, l’hématocrite, l’hémoglobine plasmatique libre et la bilirubine libre changent significativement.
L’hémoglobine plasmatique libre augmente significativement dans les deux groupes, avec un taux plasmatique significativement
plus élevé dans le groupe A. Avec les deux liquides d’irrigation, on observe une hémolyse et une hémodilution sans conséquence
clinique. Un temps de résection court, un faible niveau de pression d’irrigation, l’utilisation de l’anesthésie rachidienne
nous semblent trés importants. Une surveillance clinique et biologique attentive pendant et après la résection transuréthrale
de prostate sont nécessaires; en revanche, le choix du liquide d’irrigation ne semble pas l’élément essentiel. 相似文献
89.
To probe age-related changes in skin barrier function, transepidermal water loss (TEWL) rates have been measured in young (19–42 years) and old (69–85 years) subjects. TEWL was determined at ventral forearm skin sites, which had been occluded for 24 hr with polypropylene chambers. Baseline TEWL rates (J
, which showed no dependence on age, were measured for each subject before and after the experiment. Following removal of the occlusive chamber, TEWL was monitored continuously from t = 0.5 min until its return to the baseline (preocclusion) level, which was typically in the range of 2–7 g/m2/hr. Initial TEWL rates (mean ± SD) were found to differ significantly between young (28.6 ± 7.5 g/m2/hr; n = 26) and old (36.9 ± 10.5 g/m2/hr; n = 18) subjects (P < 0.01). Relaxation of TEWL to J
was significantly slower in the aged cohort, such that the characteristic time for diffusion of water in the stratum corneum was estimated to be (mean ± SD) 176 ± 59 min for the young subjects, compared to 360 ± 76 min for the old (P < 0.001.). Thus, the initial TEWL value following removal of occlusion is significantly greater, and the excessive stratum corneum hydration produced by occlusion is dissipated more slowly, in old skin than in young. A hypothesis to explain the slower relaxation of perturbed TEWL in old skin is proposed. 相似文献
90.
Dr. B. K. van Kreel N. Cox-Reyven P. Soeters 《Medical & biological engineering & computing》1998,36(3):337-345
Multifrequency bio-electronic impedance analysis (MF BIA) measurements are taken from a heterogeneous group of patients, varying
in size between obese and slim. The measuring system uses four electrodes: two current and two potential electrodes. Three
new models are developed to calculate total body water (TBW) from the BIA data, and the resulting TBW values are compared
with TBW determined by D2O dilution. The results demonstrate that the most simple model provides the best TBW values. For individual patients, TBW
can be determined by means of bioimpedance measurement with an accuracy of 3 litres. In the most simple model (model 1), the
body is electrically represented by a cylinder, and corrections are made for the amount of fat. This is an extension of the
model used by Xitron. In the more advanced models (2 and 3), the body is represented by a cylinder for the trunk, and truncated
cones represent the arms and legs. In model 2, ΔTBW amounts to 3 litres. It is shown that the resistance of the trunk is proportional
to the square root of the length. In model 3, it is assumed that subcutaneous fat is a poor conductor if electric current.
An equation is developed that describes the partition of subcutaneous fat, and the fat layer is then removed from the cones
representing arms and legs and from the cylinder that models the trunk. 相似文献