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BACKGROUND: Automated component collection systems offer the possibility of increasing blood supply and improving transfusion safety. DESIGN: 30 blood donors were randomly assigned to double RBC collection with either the Baxter Alyx (AX), the Haemonetics MCS Plus (MCS+), or the Gambro Trima Accel (TA). Procedures were prospectively evaluated focussing on yield, time, efficiency, citrate donor load, and in vitro quality. RESULTS: All units showed sufficient in vitro quality throughout 42 days of storage and complied with international requirements. Donor reactions were limited to mild citrate reactions. AX was the fastest and most efficient system* * (* *p approximately 0.001) attaining the highest yield* * from similar amounts of whole blood. The drawbacks were a higher RBC loss* (*p < 0.05) and accelerated citrate infusion* *. Due to lower collection rates* * * (* * *p < 0.001), MCS+ was slower than TA* * * but compensated with lower citrate load * * *. CONCLUSION: Double RBC apheresis was performed safely and efficiently with all three instruments. AX had advantages for most parameters evaluated.  相似文献   
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On December 31, 2001, 2486 patients with terminal renal failure received dialysis treatment in Croatia. Only one third of the patients are registered on the national waiting list for cadaveric kidney transplant. In most of the others, transplantation is impossible because of comorbidity. This is mainly due to the steadily growing age of the dialytic population and therefore a higher incidence of cardiovascular disease and diabetes. Still, evaluation of the potential recipients of cadaveric kidney transplant, registered on the waiting list, often reveals contraindications for transplantation. The aim of this study was to determine the incidence and type of contraindications in transplant candidates, found during immediate preoperative evaluation. Analysis of these data should help in determining how contraindications can be early detected and prevented. Before registering onto the national waiting list transplant candidates need to be thoroughly investigated including detailed history, physical examination, routine diagnostic procedures and additional examinations, if needed, to exclude or evaluate the possibly existing contraindications for transplantation. During the period from January 1997 until June 2002, 145 potential recipients from the national waiting list were referred to the Rijeka University Hospital Center and evaluated for kidney transplantation. Eighty-eight patients underwent transplantation. Preoperative evaluation revealed contraindications for transplantation in 52 (35.9%) candidates. Twenty-two (15.2%) patients had a positive cross-match with donor lymphocytes, 6 (4.1%) patients refused transplantation, and in 24 (16.6%) patients serious comorbidity was the reason for not being accepted for transplantation and for their withdrawal from the national waiting list. Comorbidity was mainly due to cardiovascular disease (12 patients--8.3%) and infection (8 patients--5.5%). These data show a high incidence of contraindications found during the immediate preoperative evaluation of potential kidney recipients. It was the case in more than one third of patients. During the evaluation of potential candidates for kidney transplantation special attention should be addressed to the presence of cardiovascular morbidity and infection. Peripheral vascular occlusive disease, cardiac status and/or cerebrovascular disease should be evaluated. Measures used to treat or reduce the development of complications include an optimal control of blood pressure, serum phosphate, hyperparathyroidism, dyslipidemia, and renal anemia. The sites of infection must be treated and eradicated, because immunosuppressive treatment is a threat to the transplant recipient's life. The second most common cause of refusal of potential candidates was a positive cross-match with donor lymphocytes. Sensitization to human leukocyte antigens can be prevented by the avoiding of blood transfusions and use of erythopoietin in treating renal anemia. To minimize the morbidity and mortality, the potential kidney recipients should undergo rigorous selection and thorough evaluation before including them into the waiting list for kidney transplantation. Afterwards, regular examinations are obligatory to reveal contraindications, proceed to medical interventions and treat concomitant diseases in time, which can influence the patient's survival. In case that contraindications for transplantation arise, the patient must be temporarily or definitely removed from the waiting list.  相似文献   
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Samples of styrene/divinylbenzene/acrylonitrile macroporous copolymers were prepared, using polystyrene as inert medium. The initial viscosity average molecular weight of the polystyrene samples were: M?v.i=87000, 98000, 117000 and 218000. The polystyrene samples with the initial molecular weights M?v.i=87000 and M?v.i=117000 were reused as inert media, for many times, until they lost their capacity to produce permanent porosity of the copolymers. The macroporous copolymers were characterized by their permanent porosity and volume swelling. If a polystyrene sample is used for many times, the molecular weight of the polystyrene removed (extracted) is gradually diminished and therefore the permanent porosity of the macroporous copolymers decreases step by step. The reasons responsible for this behaviour are:
  • during the copolymerization process a polystyrene with a smaller molecular weight is formed.
  • polystyrene parts of high molecular weights are included in the network structure of the macroporous copolymers.
The evidence for this was given by plotting the differential and integral molecular weight distribution curves for six samples of polystyrene.  相似文献   
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The aim of this study was to evaluate the Diet Quality Index (DQI) and the Physical Activity (PA) levels associated with adequacy of gestational weight gain in pregnant women with gestational diabetes mellitus (GDM). A total of 172 pregnant women with a single fetus and a diagnosis of GDM participated. Food intake was self-reported on the food frequency questionnaire and DQI was quantified using the index validated and revised for Brazil (DQI-R). To assess PA, the Pregnancy Physical Activity Questionnaire was administered. Gestational weight gain was classified, following the criteria of the Institute of Medicine, into adequate (AWG), insufficient (IWG), or excessive (EWG) weight gain. A multinomial logistic regression analysis was performed, with level of significance <0.05. The participants were divided into 3 groups: AWG (33.1%), IWG (27.3%), and EWG (39.5%). The analysis indicated that if the pregnant women PA fell into tertile 1 or 2, then they had a greater chance of having IWG, whereas those with the lowest scores on the DQI-R, whose PA fell into tertile 2, and pregestational obesity women had the greatest chance of having EWG. This study has shown that low PA levels may contribute towards IWG. On the other hand, a low final DQI-R score, representing inadequate food habits, low PA levels, and pregestational obesity may increase the chance of EWG in patients with GDM.  相似文献   
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Surgical-site infection (SSI) is the most prevalent type of hospital infection in surgical patients and is associated with an increase in hospital stay, costs and morbidity/lethality. The knowledge of the main risk factors for this type of infection is important for the establishment of prevention measures regarding modifiable risks factors. The objective of the preset study was to assess the occurrence of SSI and study the risk factors in oncologic surgeries of the digestive system at Hospital de Câncer in Barretos, São Paulo, Brazil. Individuals undergoing oncologic surgeries of the digestive system in the period of 08/01/2007 to 08/10/2008 were prospectively followed for 30 days after surgery. Possible risk factors related to the patient and to the surgical procedure were also studied. A total of 210 surgeries were analyzed, with a global SSI incidence of 23.8%. The following variables were independently associated with SSI: time and type of surgery, radiotherapy before surgery and surgeon's years of experience. The risk factors found in this study have been described by other authors and are not amenable to intervention for SSI prevention. Further studies are recommended with the objective of investigating interventions that could reduce the risk for SSI in this type of surgery.  相似文献   
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