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61.
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
62.
Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587)  相似文献   
63.
Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.  相似文献   
64.
OBJECTIVE: To evaluate impressions and usage of sinus surgery image-guided surgical (IGS) systems by ENT surgeons in the United States. STUDY DESIGN AND SETTING: A survey was mailed to selected practicing ENT physicians, investigating regional information, practice type, IGS usage patterns, perceived benefits and limitations, and usage of the 61795 surgery code. RESULTS: Seventy-three percent of respondents use IGS. Nonusers respond that it provides no benefit or is too expensive. Eighty percent of respondents replied that IGS may allow for increased safety in certain procedures. Most users attempt reimbursement with the 61795 code. CONCLUSION: IGS usage is increasing but appears to be perceived as expensive and nonbeneficial in certain situations. Most respondents, however, felt that IGS may lead to safer surgery in certain situations, including revision and frontal procedures. Several factors appear to limit routine use including ease of use, technical setup, code reimbursement, and initial purchase costs. SIGNIFICANCE: IGS use appears to be increasing. The most frequent users appear to agree with the previously issued AAO-HNS guidelines regarding appropriate indications. Expanded use may depend on ease of use, reimbursement, and affordability. EBM rating: D-5.  相似文献   
65.
The initial treatment of congenital idiopathic talipes equinovarus (clubfoot) is most often nonsurgical. However, surgical treatment in the form of posteromedial release is often undertaken after failure of conservative measures. The prevalence of both immediate and long-term complications in surgically treated clubfeet has cultivated a renewed interest in nonsurgical treatment. The Ponseti method for treating clubfoot has seen a revived interest among those caring for infantile clubfeet. We report on our first 34 infants (57 clubfeet) treated by using the techniques and principles described by Ponseti. Using a standard scoring system, 54 of 57 clubfeet were successfully corrected without requiring posteromedial release. Only 2 patients (3 clubfeet) required extensive surgical correction. There were 6 relapses. In all recurrent cases, there was a lack of compliance with the straight-last shoe and foot abduction bar regimen. Based on this level of initial success, we believe that posteromedial release is no longer necessary for the majority of cases of congenital clubfeet.  相似文献   
66.
Proximal dorsal stress risers are a potential complication to the Kalish osteotomy. The authors describe a modification to this osteotomy that is simple and effective. Since performing the wing-clip modification, there have been no observed stress risers.  相似文献   
67.
68.
In addition to race and ethnicity, specific geographic regions are associated with poorer outcomes of care. Individuals with diabetes experiencing health disparities typically have worse long-term outcomes, such as increased diabetes complications and mortality. Zip code mapping, or geocoding, was utilized in this study to identify regions of the United States with high diabetes prevalence rates and to identify areas with high densities of minority populations. Use of this methodology to examine the effect of disease management on a large, diverse diabetes population revealed greater improvement in clinical testing rates in health disparity zones compared with members living outside of these areas. In particular, significant improvement was achieved by members living in minority zip codes and by members aged 65 years or older. These findings demonstrate that members living in areas of health disparity obtain even greater benefit from diabetes disease management program participation, helping to reduce gaps in care.  相似文献   
69.
First-line therapy for hepatitis C virus (HCV) infection comprises interferon-alpha (IFN-alpha) and ribavirin for 6 or 12 months. Mild complications of therapy are common, but more serious complications are rare. Three patients with chronic HCV infection, acquired through injecting drug use, developed idiopathic facial paralysis (Bell's palsy) during therapy, with spontaneous resolution after withdrawal of treatment. Large-scale cohort studies reveal that IFNs are associated rarely with neurologic complications, and only one previous report has linked IFN-alpha therapy and Bell's palsy. We postulate that IFN-alpha therapy led to a breakdown of peripheral tolerance to myelin sheath antigens, leading to neuropathy, just as IFN-alpha therapy can cause autoimmune thyroiditis through breakdown of tolerance to native thyroid antigens.  相似文献   
70.
Using whole-cell patch clamp techniques we have examined the cellular mechanisms underlying the effects of orexin A (OX-A) on electrophysiologically identified magnocellular and parvocellular neurones in the rat hypothalamic paraventricular nucleus (PVN). The majority of magnocellular neurones (67 %) showed concentration-dependent, reversible depolarizations in response to OX-A. These effects were abolished in tetrodotoxin (TTX), suggesting them to be indirect effects on this population of neurones. OX-A also caused increases in excitatory postsynaptic current (EPSC) frequency and amplitude in magnocellular neurones. The former effects were again blocked in TTX while increases in mini-EPSC amplitude remained. Depolarizing effects of OX-A on magnocellular neurones were also found to be abolished by kynurenic acid, supporting the conclusion that these effects were the result of activation of a glutamate interneurone. Parvocellular neurones (73 % of those tested) also showed concentration-dependent, reversible depolarizations in response to OX-A. In contrast to magnocellular neurones, these effects were maintained in TTX, indicating direct effects of OX-A on this population of neurones. Voltage clamp analysis using slow voltage ramps demonstrated that OX-A enhanced a non-selective cationic conductance with a reversal potential of -40 mV in parvocellular neurones, effects which probably explain the depolarizing effects of this peptide in this subpopulation of PVN neurones. These studies have identified separate cellular mechanisms through which OX-A influences the excitability of magnocellular and parvocellular PVN neurones.  相似文献   
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