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51.
Changes in hemostasis after laparoscopic cholecystectomy   总被引:6,自引:3,他引:3  
Background: The aim of this work was to study hemostasis in laparoscopic cholecystectomy in order to determine if there are any changes that indicate a greater risk of thrombosis. Methods: The study was carried out in 20 patients who underwent laparoscopic surgery for noncomplicated cholelithiasis. The average age was 59.4 years (range, 34–77). A total of 75% were female. Mean operation time was 70 min (ranges 35–120). Pneumoperitoneum at 14 mmHg was performed on all patients, who were positioned in the 30° reverse Trendelenburg position. Postoperative mobilization was acheived in 24 hs and patients were discharged 48 hs after the operation. The control group was composed of 12 patients, who were evenly distributed by age, sex, and length of surgery. These patients underwent Bassini herniorraphy for inguinal hernia without any complications or relapse. The following hemostatic parameters were studied: prothrombin activity (PA), activated partial thromboplastin time (APTT), fibinogen (Fg), anti-thrombin III (ATIII), plasma fibrinolytic activity (PFA), euglobulin fibrinolytic activity (EFA), and D-dimer (D-D). Samples were obtained at the following times: (a) under basal conditions the day before surgery, (b) preoperatively, (c) at the end of the operation, (d) 24 hs after the operation, and (e) On the 7th day following the operation. Results: No patient showed any clinical manifestations of thromboembolic disease immediately after surgery or during a medium follow-up period of 16 months (range, 15–18 months). All hemostatic parameters values were within normal range in the basal samples of both groups. In both groups, the mean value of PA showed a significant decrease (p < 0.05) in the second, third, and fourth basal samples, returning to normal levels by the fifth determination. The mean value of fibrinogen decreased slightly in the second and third samples, increasing significantly with respect to the fourth and fifth determinations in both groups (p < 0.05). The mean value of APTT in both groups was slightly enhanced in the second and third determinations in relation to the first and fifth. The global activity of fibrinolysis (PFA and EFA) increased significantly in the third sample with respect to the other determinations in the group who had laparoscopic surgery (p < 0.005). Only EFA increased in the control group (p < 0.05). D-D decreased in the preoperative second determination followed by a significant enhancement immediate postoperatively (third), and 24 hs (fourth) (p < 0.05); it returned to normal basal values on the seventh day. No significant differences were found between the two groups. Conclusions: These results indicate that laparoscopic cholecystectomy leads to no greater activation of plasma coagulation than low-risk surgery. On the contrary, the increase of fibrinolytic activity in plasma would extend a certain degree of hypocoagulability during surgery, maintaining it for 24 hs and thus possibly reducing thromboembolic risk in patients undergoing this type of surgery. Received: 25 February 1998/Accepted: 18 August 1998  相似文献   
52.
An abridged five-item version of the 15-item International Index of Erectile Function (IIEF) was developed (IIEF-5) to diagnose the presence and severity of erectile dysfunction (ED). The five items selected were based on ability to identify the presence or absence of ED and on adherence to the National Institute of Health's definition of ED. These items focused on erectile function and intercourse satisfaction. For 1152 men (1036 with ED, 116 controls) analyzed, a receiver operating characteristic curve indicated that the IIEF-5 is an excellent diagnostic test. Based on equal misclassification rates of ED and no ED, a cutoff score of 21 (range of scores, 5-25) discriminated best (sensitivity=0.98, specificity=0. 88). ED was classified into five severity levels, ranging from none (22-25) through severe (5-7). Substantial agreement existed between the predicted and 'true' ED classes (weighted kappa=0.82). These data suggest that the IIEF-5 possesses favorable properties for detecting the presence and severity of ED.  相似文献   
53.
The aim of the present work was to study further the intrinsic organization of the dorsal ventricular ridge of lizards. For that purpose, the morphology and distribution of cells and fibers containing the calcium-binding proteins calbindin-D28k, parvalbumin, and calretinin were investigated by using immunohistochemical methods. Colocalization of calcium-binding proteins with the neurotransmitter gamma-aminobutyric acid (GABA) was also studied because they are shown to coexist in many areas of the telencephalon where they define distinct subpopulations of GABAergic local circuit neurons. Neurons containing calcium-binding proteins are limited to the anterior part of the dorsal ventricular ridge (ADVR), whereas the posterior or caudal portion of the ridge is devoid of immunoreactive cells. This result gives further evidence for defining both regions of the dorsal ventricular ridge. Calcium-binding proteins mark three distinct populations of neurons within the ADVR. Two of them, parvalbumin- and calretinin-expressing cells, are GABAergic. On the other hand, calbindin-containing neurons do not express GABA, and the possibility is discussed that these cells are projection neurons. The distribution and overall density of fibers immunoreactive to calcium-binding proteins suggests that most fibers are of extrinsic origin, the thalamic nuclei projecting to the ADVR and the lateral amygdala being good candidates for their origin. The comparison of data on the populations of calcium-binding protein-containing neurons in the reptilian ADVR with those of mammals illustrate the difficulty in finding a mammalian homologue for this controversial region of the reptilian telencephalon.  相似文献   
54.
Adenosine is known to modulate synaptic plasticity in the hippocampus of young animals through activation of adenosine A1 receptors. The objective of the present study is to investigate whether the modulatory role of adenosine on phenomena of synaptic plasticity is maintained or modified in the hippocampus of aged animals. We compared the effects of the selective adenosine A1 receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 50 nM), on paired-pulse facilitation (PPF), long-term depression (LTD), long-term potentiation (LTP) and depotentiation elicited in hippocampal slices taken from young adult (5-6 weeks) and old (2 years old) male Wistar rats. DPCPX attenuated PPF both in young (1.64 +/- 0.05 vs. 1.76 +/- 0.05%, n = 6) and in old rats (1.33 +/- 0.05 vs. 1.55 +/- 0.1%, n = 6). LTD was only observed in the presence of DPCPX in both young (21.3 +/- 0.6%, n = 4) and old rats (14.4 +/- 0.9%, n = 6). LTP induced by high-frequency stimulation (HFS) was not significantly different in young and old animals, in the presence or in the absence of DPCPX. A larger depotentiation was observed in the presence of DPCPX in young rats (27.6 +/- 4.4% vs. 16.8 +/- 4.7%, n = 7) as well as in old rats (41.3 +/- 5.1% vs. 16.1 +/- 2.7%, n = 6). LTP induced by theta-burst stimulation was observed only in the presence of DPCPX (53.9 +/- 4.9%, n = 5) in young rats, but could be obtained either in the control solution (81.8 +/- 17.9%, n = 7) or in the presence of DPCPX (98.5 +/- 24.2%, n = 7) in old rats. The modulatory role of endogenous adenosine on synaptic plasticity is generally maintained in aged animals. Drugs interfering with adenosine A1 receptor effects could then be used in old animals to modify synaptic plasticity with relevant behavioural consequences.  相似文献   
55.
The authors examined the severity and type of deficits in remote memory in patients with probable Alzheimer's disease (AD). In the first study, 40 AD patients showed significantly more severe deficits on both the free-recall and the recognition sections of the Remote Memory Scale (which measures memory for famous people and well-known events) compared with normal control subjects. In the second study, 25 AD patients showed significantly more deficits on the free-recall section of the Autobiographical Memory Scale compared with normal control subjects. Remote memory deficits in AD may be related to both retrieval deficits and damage to memory traces.  相似文献   
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59.
Bone Mineral Density and Androgen Levels in Elderly Males   总被引:4,自引:0,他引:4  
To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years) the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied. BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related factors must be associated with bone loss in elderly males. Received: 29 April 1997 / Accepted: 9 November 1997  相似文献   
60.
To investigate 1) the correlation between the proliferative activity of epididymal epithelium plus myoid cells and the increase in the number of these cells and 2) the role of the basal epithelial cells in the renewal of epididymal epithelium, a quantitative evaluation of the proliferation of both epithelial cells and periductal myoid cells in the different epididymal regions (caput, corpus, and cauda) has been carried out during postnatal development of the rat by immunohistochemical evaluation of BrdU-labeling indices. These data were correlated with cell numbers and counted by the optical dissector method. The presence of bcl-2 protein was immunohistochemically detected and evaluated. No significant differences in BrdU indices were observed among epididymal regions in any stage studied. Cell proliferation decreased from the prepubertal period to adulthood in both epithelial and myoid cells in the three regions of the epididymis, suggesting a close relationship between epithelial and mesenchymal components. The numbers of both cell types were significantly higher in the caput than in the corpus and cauda in all stages studied, suggesting functional differences between regions. A negative linear correlation between proliferative activity and cell numbers was noted that might be related to regulation of the cell population size. Basal cells showed a lower proliferation rate than principal cells, but most of the immunoreactive bcl-2 protein, in pubertal and adult epididymides, was observed in basal cells. Therefore, these cells might comprise a low-proliferating and apoptosis-resistant population.  相似文献   
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