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11.
Health policies are correlated with the economics resources invested in each specific field. The planning of organ transplant centres depends on the relationship between health demand and health offer. The health demand is due to the number of the patients which are waiting for a transplant, while the health offer is represented by all the specific resources: number of cadaver donors and transplant centres. The analysis of transplant activity performed in Italy during the period 1996-1998 suggests that it is not necessary to increase the number of transplant centres but that of organ donors.  相似文献   
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AIM: Morbid obesity has increased its frequency in the last 20 years in association with the increase of a country's richness. Bariatric surgery has developed a role which is becoming more and more important. The aim of this study, after 10 years of experience with the biliopancreatic diversion, is to compare the laparoscopic versus open technique RESULTS: METHODS: From March 1993 to December 2004, 150 patients were operated by biliopancreatic diversion. We divided our experience into 2 groups: laparotomic and laparoscopic techniques. We compared the following variables in the 2 groups: total operating time, intestinal functions, postoperative pain, patient's discharge and recovery time, major postoperative complications, postoperative mortality, late complications, incisional hernia incidence and anastomotic ulceration. RESULTS: We found a significant difference in both the reduction of the postoperative pain and the recanalization time in the laparoscopic group. Equally, we found a reduction in the incidence of abdominal wall complications, especially the reduction of incisional hernia and infections. The mean operative time was longer in the laparoscopic group, in particular due to the hard learning curve. CONCLUSIONS: The laparoscopic biliopancreatic diversion is a feasible and safe operation with good results: less postoperative discomfort, shorter recanalization and ospedalization time, less incidence of abdominal wall morbidity (incisional hernia). However, the procedure may prove difficult and it needs a highly experienced surgeon in laparoscopic technique.  相似文献   
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Platelet size does not correlate with platelet age   总被引:14,自引:0,他引:14  
The relationship between platelet size and in vivo aging was investigated in the baboon using size-dependent platelet subpopulations separated by counterflow centrifugation. The separation characteristics, size, lactate dehydrogenase (LDH) activity, and dense- body content of the baboon platelet subpopulations were similar to those previously observed in studies of human platelets. Three independent labeling techniques were used: (1) in vivo labeling with 75Se-methionine, (2) in vitro labeling with 51Cr, and (3) in vivo labeling with 14C-serotonin. Maximal incorporation of all three labels showed a close correlation between the mean platelet volume (MPV) of each fraction and the platelet radioactivity. The onset of incorporation and rate of accumulation of 75Se-methionine were comparable in all fractions when corrected for differences in volume, suggesting that platelet size heterogeneity was present from the time of release of the platelets from the bone marrow. Survival studies using 51Cr and 14C-serotonin showed no translocation of the label from one fraction to another in the circulation over time. In vivo survival values for the three radionuclides showed a slight but significant correlation between the lifespan and the MPV of the fractions. The data suggest that large platelets were not younger platelets, but rather platelets with a longer life-span. Platelet size heterogeneity is the result of production factors in the bone marrow and not maturation in the circulation.  相似文献   
16.
BACKGROUND/AIMS: Experimental radiofrequency ablation has already been performed in healthy livers of porcine models, but not in less expensive and easy-to-manage rats, with devices capable of delivering radiofrequency ablation in the 20-30 g liver of such small animals being so far unavailable. METHODOLOGY: We experimented with a modified system of radiofrequency ablation of liver tissue in rat models developing a custom-made needle-microelectrode of very small dimensions (0.3x2 mm) and an electrode-tip cooling technique, based on saline solution infusion. We adjusted duration (seconds) and power (watts) of radiofrequency ablation letting them range between 5-50 seconds and 5-25 W, respectively, to obtain the greatest lesions with the least side effects. After sacrificing the animals, an accurate histological examination of the liver was made. RESULTS: It is possible to establish beforehand the diameter of thermal liver lesion on the basis of joules of applied energy. The greatest increase of liver thermal lesion diameter (8 mm) is obtained with a 250-joule (10 W for 25 seconds) thermal energy cooling the electrode-tissue interface. CONCLUSIONS: Experimental radiofrequency ablation in rat liver is an effective and cheap way to study its effects on healthy hepatic tissues. It might be the first step to treat experimentally caused liver tumors.  相似文献   
17.
Adaptive cardiac binding, a new surgical procedure for advanced heart failure, allows a gradual increase in compression on the dilated heart, with separate loads on the left and right ventricles. A canine model of biventricular heart failure (anastomosis between the carotid artery and jugular vein and doxorubicin administration) was created. Twenty-four dogs were divided into 4 groups: control, adynamic cardiomyoplasty, plastic cardiac binding, and adaptive cardiac binding. In the adaptive cardiac binding group, fluid was added (35, 15, and 10 mL) to each side of the pouch at weeks 1, 2, and 3. Left ventricular ejection fraction was 59%+/-4% before induction of heart failure and 27%+/-2% 6 weeks later. Immediately after the main operation, left ventricular ejection fractions were 35+/-3% (cardiomyoplasty), 34%+/-4% (plastic cardiac binding), and 35%+/-4% (adaptive cardiac binding). Four weeks later, left ventricular ejection fraction had not changed in the cardiomyoplasty (37%+/-3%) and plastic cardiac binding (32%+/-2%) groups, but significantly increased in the adaptive cardiac binding group (48%+/-5%); it had decreased to 23%+/-4% in controls. Adaptive cardiac binding is a promising new surgical approach for patients with end-stage heart failure.  相似文献   
18.
A method for the separation of platelets on the basis of their size has been developed using counterflow centrifugation. Platelets were separated, free of plasma proteins and other cells, into seven subpopulations. The smallest-sized platelets, designated as Fraction 1, had a mean platelet volume (MPV) of 3.94 ± 0.60 μm3 (SD). Each successive fraction had a progressively larger MPV. The MPV for the largest-sized platelets, designated Fraction 7, was 8.19 ± 0.64 μm3. The MPV for the original platelets prior to fractionation was 6.57 ± 0.61 μm3. The mean density of Fraction 1 platelets was 1.067 ± 0.002 g/cm3, while Fraction 7 had a mean density of 1.072 ± 0.001 g/cm3. Transmission electron microscopy demonstrated that Fraction 1 had 4.3 ± 0.9 dense bodies per platelet, and Fraction 7 had 12.6 ± 2.4 dense bodies per platelet. Platelet LDH activity showed that the Fraction 1 platelets had 4.77 ± 0.92 iu per 1010 platelets; Fraction 7 platelets had 14.88 ± 1.23 iu per 1010 platelets. The LDH activity in the platelets before separation into subpopulations was 9.47 ± 1.45 iu per 1010 platelets.  相似文献   
19.
Selective Alzheimer's disease indicator-1 (seladin-1) is a novel gene with antiapoptotic activity that is down-regulated in vulnerable brain regions in Alzheimer's disease. This gene encodes 3-beta-hydroxysterol Delta-24-reductase (DHCR24), which converts desmosterol into cholesterol. In the adrenal cortex, increased expression of seladin-1/DHCR24, which appears to be modulated by ACTH, has been recently reported in cortisol-secreting adenomas, compared with the adjacent atrophic tissue. In our study, we measured the expression level of seladin-1/DHCR24 in cortisol- (n = 18) and aldosterone-secreting (n = 16) adrenocortical adenomas, in carcinomas (n = 17), and in normal adrenal glands (n = 8) by quantitative real-time RT-PCR. The amount of seladin-1/DHCR24 mRNA was significantly reduced in carcinomas (total RNA, 2.5 +/- 0.8 pg/ micro g) compared with the other groups (P < 0.01). Western blot analysis confirmed the mRNA results. Similarly, in adrenal malignancies, significantly reduced levels of expression of the ACTH receptor gene were found. In the adrenal cancer cell line H295R and in primary cultures from adrenocortical cells, ACTH (1 nM) and forskolin (10 micro M) effectively increased seladin-1/DHCR24 expression, confirming that seladin-1/DHCR24 is modulated by the ACTH/cAMP-driven pathway. In summary, this is the first demonstration that seladin-1/DHCR24 expression is reduced in adrenal cancer, suggesting that it might be viewed as a new potential marker of adrenal malignancies.  相似文献   
20.
The mechanism of erythropoietin (Ep) production after acute haemorrhage has been thought to be due to a reduction in blood volume and tissue perfusion leading to tissue hypoxia. In the present study we have evaluated the effect of acute haemorrhage in the rat on the acid-base status, the red cell affinity for oxygen in vivo, and Ep production. Within a few hours after acute blood loss there was a respiratory alkalosis with an increase in blood pH, a decrease in pCO2 and an increase in the red cell affinity of Hb for oxygen in vivo that was temporally related to an increase in Ep production. Within 24 h after the acute haemorrhage, the blood pH AND PCO2, red cell affinity for oxygen in vivo, and Ep level returned towards normal. The decrease in in vivo red cell affinity for oxygen was associated with an increase in red cell 2,3-DPG levels and a decrease in Ep production.  相似文献   
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