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11.
Building on central place theory, we offer a series of simple location models for US credit unions. Credit unions are historically viewed as a community-based strategy designed to fill voids in spatial financial markets. Unlike banks and more traditional retail financial institutions, our results show that credit unions operate in areas with a low concentration of retail banks. This suggests that credit unions do not follow the ??herd?? mentality that dominates traditional retail banking institutions. Instead they cluster around common bonds of association. That is credit unions are fundamentally capturing a different market than traditional banks and do not behave in a pro-competitive manner with banks. In the spirit of Bitter et?al. (J Geogr Syst 9:7?C27, 2007), we compare the overall performance of geographically weighted regression with a set of both spatial and non-spatial estimators. We find that the spatial estimators generally performed better than the aspatial estimators, and there is significant spatial heterogeneity in some of the determinants of credit union concentrations. Results on individual variables of interest tend to be stable across the different estimators lending confidence to our hypothesis that credit unions serve niche markets.  相似文献   
12.
The gastrointestinal tract has great importance in HIV infection because of its role as a primary barrier to the external environment and consequent need for effective immune function. Many factors promote the development of diarrhea in HIV-infected individuals. Understanding the genesis of the symptom is key to formulating effective therapy. Ultimate control of the problem depends on preventing HIV replication and immune depletion, as well as avoiding the development of opportunistic enteric infections in patients with severe immune deficiency.  相似文献   
13.
Orthotopic cardiac transplantation is an established treatment for terminal cardiac diseases. The organization of the operation closely depends on the successful team work between cardiologists, selecting the proper patients for this procedure, the anesthesiologists taking care of the multiorgan donor and the cardiac surgeons managing in parallel the donor and the recipient. Accurate donor evaluation and treatment are essential for a perfect graft function immediately after transplantation. Orthotopic heart transplantation can also be offered as a therapeutical option in adolescents presenting with end-stage heart failure due to complex congenital heart disease and who have sustained multiple previous operations. In this paper, some special logistic and technical particularities of cardiac transplantation are presented and discussed.  相似文献   
14.
The use of xenografts could relieve the chronically inadequate supply of human organs for transplantation, but doubts have been expressed about the general acceptability of transplanting animal organs into human. Some researchers and clinicians have chosen to ignore negative attitudes towards clinical xenotransplantation, assuming that people will automatically embrace this new technology when it becomes available. A review of eight studies of attitudes to xenotransplantation did not reveal overwhelming support for it. Particularly negative views were expressed by acute care nurses. Primates have been the donors of choice in clinical xenotransplantation to date, but their continued use is a highly contentious option; the preferred animal donor is now clearly the pig. Animal farming for xenotransplantation is generally regarded as acceptable since animals provide food for man and are an accepted source of items for human use such as heart valves and insulin. Open debate about xenotransplantation must now take place, and present attitudes may change as a result of this. However, it remains to be seen whether xenografts will be widely accepted and used, and the extent to which the chronic shortage of organs for transplantation will thereby be alleviated.  相似文献   
15.
Ultra-shallow (below 20 nm) disorder profiles have been characterized by spectroscopic ellipsometry (SE). The implanted depth region has been divided into sublayers with dielectric functions calculated by the effective medium approximation using single-crystalline and disordered components. The damage depth profile has been parameterized using a box model, an independent multilayer model, a graded multilayer model, an error function, and Gaussian profiles. Literature values and Tauc-Lorentz (TL) parametrization as well as multi-sample and single-sample approaches have been compared to describe the dielectric function of the disordered component. The distribution of the implanted ions and/or damage have been cross-checked using medium energy ion scattering (MEIS), transmission electron microscopy and Monte Carlo simulations. We found a good agreement in the damage profiles obtained by the different methods. There is an offset between the SE and MEIS damage profiles due to the fact that SE is very sensitive to the surface roughness, in contrast to MEIS. The correlation between this offset and the surface roughness has been investigated using atomic force microscopy.  相似文献   
16.
In previous studies using isolated, paced guinea pig left atria, we observed that FSCPX, known as a selective A1 adenosine receptor antagonist, paradoxically increased the direct negative inotropic response to A1 adenosine receptor agonists (determined using concentration/effect (E/c) curves) if NBTI, a nucleoside transport inhibitor, was present. Based on mathematical modeling, we hypothesized that FSCPX blunted the cardiac interstitial adenosine accumulation in response to nucleoside transport blockade, probably by inhibiting CD39 and/or CD73, which are the two main enzymes of the interstitial adenosine production in the heart. The goal of the present study was to test this hypothesis. In vitro CD39 and CD73 inhibitor assays were carried out; furthermore, E/c curves were constructed in isolated, paced rat and guinea pig left atria using adenosine, CHA and CPA (two A1 adenosine receptor agonists), FSCPX, NBTI and NBMPR (two nucleoside transport inhibitors), and PSB-12379 (a CD73 inhibitor), measuring the contractile force. We found that FSCPX did not show any inhibitory effect during the in vitro enzyme assays. However, we successfully reproduced the paradox effect of FSCPX in the rat model, mimicked the “paradox” effect of FSCPX with PSB-12379, and demonstrated the lipophilia of FSCPX, which could explain the negative outcome of inhibitor assays with CD39 and CD73 dissolved in a water-based solution. Taken together, these three pieces of indirect evidence are strong enough to indicate that FSCPX possesses an additional action besides the A1 adenosine receptor antagonism, which action may be the inhibition of an ectonucleotidase. Incidentally, we found that POM-1 inhibited CD73, in addition to CD39.  相似文献   
17.
18.
Early release after cardiac surgery can be promoted by implementation of a standard protocol for accelerated perioperative and early postoperative care, with optimal education and support of the patient playing a key role. We report on our preliminary experience with 100 selected patients who underwent a "fast track" protocol following coronary artery bypass (n = 61), valve replacement or reconstruction (n = 34) or closure of an atrial septal defect (n = 5) between 1996 and 1998. Surgery was performed through a midline sternotomy using normothermic or mild hypothermic cardiopulmonary bypass. Patients undergoing cardiac surgery with less invasive techniques were excluded from this study. The following criteria had to be fulfilled for early hospital discharge: sinus rhythm, temperature below 37.5 degrees C, stable haematocrit around 0.30, uncomplicated wound healing and complete mobilisation including stair exercises. Mean duration of the operation was 137 +/- 24 minutes and mean intubation time was 4.5 +/- 3 hours. Mean duration of hospitalisation from the day of the operation was 4.9 +/- 2.1 days. There was no early or late mortality in this group of patients and only 2 patients had to be re-admitted on postoperative day 10 and 14 because of atrial fibrillation in one and a wound healing problem in the other. Accelerated recovery and early hospital discharge is highly attractive in selected patients; in helps to promote early cardiac rehabilitation and the costs of the procedure can be substantially reduced. According to our experience and the most recent literature, this approach does not expose patients to higher mortality or morbidity. In addition, fast-tracked patients have shown a higher level of satisfaction. Under optimal cooperation between surgery, anaesthesiology and intensive care unit, the fast-track protocol can be applied in approximately 30% of overall adult cardiac surgery patients.  相似文献   
19.
OBJECTIVE: At present debate continues concerning the optimal mode of treatment for type B dissections. Controversies are mainly due to discordant results regarding survival following medical or surgical treatment. We assessed early and long-term outcome of acute dissection of the descending aorta treated by emergency aortic replacement, medical treatment or delayed surgery. METHODS: Between 1980 and 1995, 225 patients were hospitalized in the medical or surgical department of our institution with the diagnosis of acute type B aortic dissection. A total of 38 patients (16.8%) underwent replacement of the descending aorta within the first week after hospital admission. Primary indications for immediate surgery were: rupturing aneurysm (n = 15), diameter of the descending aorta (n = 13), malperfusion of the thoracoabdominal aorta (n = 8) and pseudocoarctation syndrome with uncontrollable hypertension (n = 2). All other patients (n = 187) underwent primary conservative treatment on the intensive care unit, including appropriate anti-hypertensive medication. In 12 of them, surgery was denied because of age or significant concomitant diseases. RESULTS: Hospital mortality after urgent or emergency surgery was 21% (8/38 patients) for the overall time period. There has been a significant decrease in hospital mortality during the last 5 year-period (12% versus 30% between 1980 and 1994). Causes of death were: cardiac failure in 3, bleeding complications in 2, postoperative mesenteric ischemia in 2 and septicemia in one patient. From the 30 operative survivors, 9 (30%) patients required further surgery on the native aorta after a mean follow-up of 48 +/- 13 months. Hospital mortality during conservative treatment was 17.6% (33/187 patients). Main causes of death were rupture in 14, thoraco-abdominal malperfusion in 13 and cardiac failure in 3 patients, whereas in 3 patients, the cause of death could not be evaluated. In this group, 9 patients had to be shifted to early surgery during the initial hospitalization because of impending rupture (n = 4), rapidly increasing diameter (n = 2) and suspicion of intestinal ischemia (n = 3). After hospital discharge, surgery for chronic dissection was performed in 47 patients, mainly because of expanding descending aortic aneurysm. Hospital mortality was 8% (4/47 patients). Actuarial survival rates after surgery during the first admission were 85 +/- 6% at 5 years and 61 +/- 8% at 10 years, versus 76 +/- 5 and 50 +/- 7% respectively, following conservative treatment (P < 0.001). CONCLUSION: Nowadays, acute type B dissection can be treated surgically with a reasonable perioperative risk. Despite aggressive anti-hypertensive treatment, hospital mortality of primary conservative treatment is still high and a substantial percentage of patients requires surgery during initial hospitalization. Main causes of death in both groups are rupture and abdominal malperfusion: therefore, closed clinical and radiologic assessment of the whole thoraco-abdominal aorta is of utmost importance. Long-term results are satisfying; unlimited radiographic follow-up allows for detection of potential severe complications and for proper planning of elective reoperations when indicated.  相似文献   
20.
Wireless Personal Communications - According to world health statistics 285 million out of 7.6 billion population suffers visual impairment; hence 4 out of 100 people are blind. Absence of vision...  相似文献   
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