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21.
Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease.  相似文献   
22.
Free flaps have been used for over 30 years. During this period, improved anatomical understanding has increased donor options and available pedicle lengths, permitting safer, single-stage reconstructions with simpler anastomoses. Refinements, such as perforator flaps in particular, have greatly improved donor morbidity, recipient site cosmesis, and the ability to replace 'like with like' while retaining options for innervation. This case highlights the evolution from one of Europe's first free tissue transfers, effectively a perforator flap, through the advent of free muscle flaps to the current generation of contourable perforator flaps. Free flap transfer has become increasingly sophisticated, safer, and more predictable, yet the potential quality of reconstructive outcome has changed little.  相似文献   
23.
OBJECTIVE: The purpose of this study was to determine whether social skills training can improve the social interaction skills of adolescents with craniofacial conditions (CFCs) in a natural environment (school lunchroom). DESIGN: This study used a pre-post between-group comparison design. Differences between treatment and control subjects were analyzed via a repeated measures analysis of variance. SETTING: The observations were conducted in the respective school lunch-rooms of the adolescents. Social skills groups were conducted in an outpatient clinic setting. MAIN OUTCOME MEASURES: Structured data based on 45 minutes of observation was coded for type, frequency, and duration of social contact. Specific measures included subject initiations and responses, peer initiations and responses, conversation events, total positive communication, and frequency of nondirected comments. RESULTS: Both target and peer-controlled total communication improved across time with adolescents receiving social skills intervention showing significantly more improvement than those adolescents not receiving direct social skills interventions. Adolescents receiving treatment participated in significantly more target initiated conversations lasting at least three interchanges and showed a trend toward a greater frequency of target initiations and positive responses to peer initiations. Peers were more likely to respond to treatment subject initiations after intervention. Fewer treatment subjects used nondirected communication, whereas control subjects continued to use nondirected communication at a slightly increased frequency. CONCLUSIONS: This study provides preliminary evidence that social skills training can increase the frequency of positive social interactions with peers for adolescents with CFCs.  相似文献   
24.
Background: Bupivacaine retards myocardial acidosis during ischemia. The authors measured function of rat isolated hearts after prolonged storage to determine whether bupivacaine improves cardiac protection compared with standard cardioplegia alone.

Methods: After measuring cardiac function on a Langendorff apparatus, hearts were perfused with cardioplegia alone (controls), cardioplegia containing 500 [mu]m bupivacaine, or cardioplegia containing 2 mm lidocaine; were stored at 4[degrees]C for 12 h; and were then reperfused. Heart rate and left ventricular developed pressures were measured for 60 min. Maximum positive rate of change in ventricular pressure, oxygen consumption, and lactate dehydrogenase release were also measured.

Results: All bupivacaine-treated, four of five lidocaine-treated, and no control hearts beat throughout the 60-min recovery period. Mean values of heart rate, left ventricular developed pressure, maximum positive rate of change in ventricular pressure, rate-pressure product, and efficiency in bupivacaine-treated hearts exceeded those of the control group (P < 0.001 at 60 min for all). Mean values of the lidocaine group were intermediate. Oxygen consumption of the control group exceeded the other groups early in recovery, but not at later times. Lactate dehydrogenase release from the bupivacaine group was less than that from the control group (P < 0.001) but did not differ from baseline.  相似文献   

25.
We previously showed that a low frequency (1 Hz) train of perforant path stimulation evokes burst discharges in the dentate gyrus of hippocampal slices obtained from patients surgically treated for intractable temporal lobe epilepsy. We report here that multiple population spikes that characterize the burst discharge are blocked reversibly by the specific NMDA receptor antagonist, D-(-)-2-amino-5-phosphonovaleric acid (D-APV). The epileptiform discharge evoked in human dentate gyrus by stimulation trains of 1 Hz could be reproduced in the rat dentate gyrus in vitro by the same stimulation protocol but required the presence of low concentrations (0.2-0.6 mM) of extracellular magnesium. We suggest that low frequency orthodromic stimulation of dentate granule cells through the perforant path progressively evokes an increase in the activation of NMDA receptors resulting in burst discharges in tissue from epileptic patients.  相似文献   
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As presently understood, evidence based medicine aims to advance practice from its traditional unverifiable mix of art and science to rational use of measurable inputs and outputs. In practice, however, its advocates accept uncritically a desocialised definition of science, assume that major clinical decisions are taken at the level of secondary specialist rather than primary generalist care, and ignore the multiple nature of most clinical problems, as well as the complexity of social problems within which clinical problems arise and have to be solved. These reductionist assumptions derive from the use of evidence based medicine as a tool for managed care in a transactional model for consultations. If these assumptions persist, they will strengthen reification of disease and promote the episodic output of process regardless of health outcome. We need to work within a different paradigm based on development of patients as co-producers rather than consumers, promoting continuing output of health gain through shared decisions using all relevant evidence, within a broader, socialised definition of science. Adoption of this model would require a major social and cultural shift for health professionals. This shift has already begun, promoted by changes in public attitudes to professional authority, changes in the relation of professionals to managers, and pressures for improved effectiveness and efficiency which, contrary to received wisdom, seem more likely to endorse cooperative than transactional clinical production. Progress on these lines is resisted by rapidly growing and extremely powerful economic and political interests. Health professionals and strategists have yet to recognise and admit the existence of this choice.  相似文献   
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Surgical services are an important part of modern health care, but providing them to isolated rural citizens is especially difficult. Public policy initiatives could influence the supply, training, and distribution of surgeons, much as they have for rural primary care providers. However, so little is known about the proper distribution of surgeons, their contribution to rural health care, and the safety of rural surgery that policy cannot be shaped with confidence. This study examined the volume and complexity of inpatient surgery in rural Washington state as a first step toward a better understanding of the current status of rural surgical services. Information about rural surgical providers was obtained through telephone interviews with administrators at Washington's 42 rural hospitals. The Washington State Department of Health's Commission Hospital Abstract Recording System (CHARS) data provided a count of the annual surgical admissions at rural hospitals. Diagnosis-related group (DRG) weights were used to measure complexity of rural surgical cases. Surgical volume varied greatly among hospitals, even among those with a similar mix of surgical providers. Many hospitals provided a limited set of basic surgical services, while some performed more complex procedures. None of these rural hospitals could be considered high volume when compared to volumes at Seattle hospitals or to research reference criteria that have assessed volume-outcome relationships for surgical procedures. Several hospitals had very low volumes for some complex procedures, raising a question about the safety of performing them. The leaders of small rural hospitals must recognize not only the fiscal and service benefits of surgical services--and these are considerable--but also the potentially adverse effect of low surgical volume on patient outcomes. Policies that encourage the proper training and distribution of surgeons, the retention of basic rural surgical services, and the rational regionalization of complex surgery are likely to enhance the convenience and safety of surgery for rural citizens.  相似文献   
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