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101.
Whitaker C  Burton DC  Asher M 《Spine》2000,25(18):2312-2318
STUDY DESIGN: This is a retrospective analysis of 23 patients with severe neuromuscular spinal deformity treated with posterior instrumentation and fusion ending in the lumbar spine. OBJECTIVES: The purposes of this study were to determine the safety and efficacy of stopping posterior instrumentation constructs in the lumbar spine with pedicle screw anchorage. SUMMARY OF BACKGROUND DATA: There are sparse data in the peer-reviewed literature regarding indications and outcomes in patients with neuromuscular disorders for instrumented fusion ended short of the pelvis with transpedicular fixation. METHODS: The average age of patients at surgery was 18.4 years (range, 10-61 years). Additional anterior discectomy and fusion were performed in four patients with large, stiff curves. No patient received anterior instrumentation. Criteria for exclusion of the pelvis from the fusion were less than 15 degrees of pelvic obliquity as a result of a compensatory curve below the major curve(s), the absence of problematic lower extremity contractures, and, often, the potential for ambulation. Process and clinical outcomes and complications were analyzed. RESULTS: Radiographic follow-up was available in 21 patients at an average of 62 months (range, 24-110 months) after surgery. Their average Cobb angle was 71 degrees before surgery, 25 degrees after surgery (64% correction), and 32 degrees at follow-up (54% correction). Their average spinal-pelvic obliquity was 6 degrees before surgery, 5 degrees after surgery, and 6 degrees at follow-up. The average lower instrumented vertebra was lumbar 3.7. Clinical follow-up was available for all 23 patients for an average of 61 months (range, 24-110 months). There were no perioperative deaths, deep wound infections, pseudarthroses, or instrument failures. Outcomes based on responses to questionnaires completed by patient, parent, or caregiver were highly satisfactory in 20 patients (87%), satisfactory in 2 patients (9%) and neither satisfactory nor unsatisfactory in 1 patient (4%). CONCLUSION: Posterior instrumentation and arthrodesis using lumbar lower instrumented vertebra pedicle screw anchorage can be performed safely and effectively, in selected patients patients with scoliosis and minimal pelvic obliquity.  相似文献   
102.
Two major crotamine isoforms (F22 and F32) were obtained after three chromatographic steps and were assayed in mouse phrenic nerve-diaphragm preparations. F32 and F22 (0.5 microg/ml, n=4) produced a facilitatory effect, which increased isometric twitch-tension by 300 and 230%, respectively, after a 120 min incubation. At a concentration of 0.1 microg/ml, both isoforms increased the twitch-tension by about 160%. However, when the isoforms were co-incubated (final concentration, 0.5 microg/ml) for 30 min prior to testing, they did not cause the facilitation seen with > or =0.1 microg/ml of each isoform alone. Histologically, F32 and F22 at 0.5 and 1 microg/ml were quantitatively alike in inducing tissue myonecrosis. However, a mixture of the two isoforms (final concentration, 0.5 microg/ml) significantly attenuated the damage seen with either toxin alone. Mass spectrometry analysis showed that the isoforms had the same molecular mass (4.8 kDa) and that they existed as monomers with a highly stable structure. These results indicate that F22 and F32 acted on muscle cells of the mouse phrenic-nerve diaphragm preparation through similar mechanisms. Since the isoforms did not produce the expected summation in the increase in muscle twitch-tension, it is possible that they may have different affinities for the sodium channel subunits.  相似文献   
103.
PURPOSE: We describe the short and intermediate-term quality-of-life (QOL) outcomes in patients treated on a randomized clinical trial in early-stage Hodgkin's disease (Southwest Oncology Group [SWOG] 9133) comparing subtotal lymphoid irradiation (STLI) with combined-modality treatment (CMT). PATIENTS AND METHODS: Two hundred forty-seven patients participated in the QOL study (SWOG 9208), completing several standardized instruments (Symptom Distress Scale; Cancer Rehabilitation Evaluation System - Short Form; Medical Outcomes Study 36-Item Short-Form Health Survey Vitality Scale; and a health perception item), as well as questions about work, marital status, and concerns about having children. This article reports on results from baseline before random assignment, at 6 months, and at 1 and 2 years after random assignment. RESULTS: Patients receiving CMT experienced significantly greater symptom distress (P <.0001), fatigue (P =.001), and poorer QOL (P =.015) at 6 months than the STLI patients, reflecting a shorter time since completion of therapy in the CMT arm. Importantly, patients in the two groups did not differ on any outcomes at the 1-and 2-year assessments. Both patient groups reported significantly more fatigue before treatment than healthy reference populations, and fatigue did not improve in either group after treatment. CONCLUSION: This study demonstrated that patients with early-stage Hodgkin's disease experience a short-term decrease in QOL and an increase in symptoms and fatigue with treatment, which is more severe with CMT; by 1 year, however, CMT and STLI patients report similar outcomes. Fatigue scores for both arms were lower at baseline than scores for the general population and did not return to normal levels 2 years after random assignment. The mechanisms responsible for this lingering problem warrant further investigation.  相似文献   
104.
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.  相似文献   
105.
In this low-income Turkish sample, parents reported on father and mother division of childcare labor and satisfaction with division. Regardless of whether they were rearing typical or atypical children, mothers reported a higher level of involvement than fathers in every domain of childcare. In general, both mothers and fathers reported slight dissatisfaction with their own level of participation in childcare. Across groups, all mothers were significantly more dissatisfied (than their spouses were with their level of participation) with the fathers' level of participation in childcare. Best predictors of parental involvement were parent's employment status, satisfaction with partner level of involvement, and parent educational level.  相似文献   
106.
BACKGROUND: Implant systems that realign and stabilize a deformed spine continue to evolve. The purpose of the study of this case series was to determine the safety and effectiveness of a system designed to integrate hook, wire, screw, and post anchors for the treatment of a wide spectrum of neuromuscular disorders associated with pelvic deformity or the potential for deformity. METHODS: Forty-seven consecutive patients who had a spinal deformity that was due to cerebral palsy or an upper motor-neuron cerebral palsy-like disease (thirty-one patients), myelomeningocele (nine), Duchenne muscular dystrophy (four), or other disorders (three) were managed with Isola-Galveston instrumentation and arthrodesis. The average age at the time of the operation was fourteen years and three months (range, five years and four months to twenty-three years and nine months). Eight patients (17 percent) had an additional anterior discectomy and arthrodesis without instrumentation, and three (6 percent) had an additional decancellation egg-shell osteotomy. The forty-seven patients were followed for an average of forty-seven months (range, twenty-four to 100 months). The complications were tabulated to assess the safety of the procedure, and the correction of each deformity was calculated to determine the efficacy. RESULTS: There were no deaths, acute wound infections, or serious neurological problems. Reoperation was necessary in five patients (11 percent). One reoperation was performed because of a delayed deep wound infection; one, because of delayed sterile drainage; and one, for a pseudarthrosis repair. The remaining two reoperations were done for removal of an implant because the cephalad portion had become prominent. In addition to the pseudarthrosis that required a reoperation, there were three possible pseudarthroses that did not require a reoperation (overall prevalence of pseudarthrosis, 9 percent). Postoperative bracing was used for eleven patients (23 percent); it did not influence the rate of pseudarthrosis or possible pseudarthrosis. The average preoperative scoliosis of 70 degrees was corrected to 24 degrees (a 66 percent correction) at the time of the latest follow-up, and the average preoperative pelvic obliquity of 27 degrees was corrected to 5 degrees (an 81 percent correction). A survey of the patients, parents, and caregivers indicated that 96 percent of them were satisfied or very satisfied with the result of the operation. CONCLUSIONS: Isola-Galveston instrumentation seems as safe and effective as other types of instrumentation that have been studied in comparable series in the literature. Isola-Galveston instrumentation is probably more effective for the correction of pelvic obliquity and the maintenance of correction. Only a posterior procedure is used, and the instrumentation appears to decrease the need for an additional anterior approach. Spinal hook, wire, screw, and post anchors have been successfully integrated into one posterior spinal implant system.  相似文献   
107.
Mamillary and spinous process base wiring did not improve L5-L6 posterolateral fusion rate, stiffness, or strength in a previously established rabbit model. Specimen radiography significantly underestimated fusion rate when compared with manual palpation (37% versus 68%). Fused specimens were significantly stiffer (67.2 N/mm versus 41.1 N/mm) and stronger (177 N versus 121 N) in tension than were nonfused specimens. Deep wound infection, detected only at the time of sacrifice, apparently was more common with internal fixation (43% versus 21%). Noninfected specimens were significantly stiffer (63.3 N/mm versus 43.0 N/mm) and stronger (176 N versus 107 N) than were infected specimens.  相似文献   
108.
PURPOSE: To explore potential psychosocial predictors for initiation of sexual intercourse among middle-school, inner-city youth, using longitudinal data from the Healthy and Alive! project. METHODS: We conducted hierarchical, logistic regression with adjustment for intraclass correlation over two sequential periods, including seventh and eighth grades (N = 3163), to assess the independent influence of psychosocial and demographic factors. Internally reliable scales to assess psychosocial influences were created, based on major theories of behavior. The sample was 52% female, 51% black, 30% Hispanic, 9% white, and 3% Asian. At baseline, 13% of girls and 39% of boys reported already having initiated sexual intercourse. RESULTS: Personal and perceived peer norms about refraining from sex were a strong and consistent protective factor. Alcohol and other drug use, poor academic performance, male gender, and black race were consistent risk factors. Self-efficacy showed a mixed effect: protective in the seventh grade but increasing risk in the eighth grade. Speaking a language other than English was a protective factor in seventh grade. Both psychosocial and demographic factors provided independent explanatory power. CONCLUSIONS: Psychosocial factors, particularly norms about having sex, influence initiation of sexual intercourse. These data suggest that programs to delay initiation of sexual intercourse should reinforce norms about refraining from sex.  相似文献   
109.
We have previously demonstrated that rabbit antisera raised against crotoxin from Crotalus durissus cascavella venom (cdc-crotoxin) and its PLA2 (cdc-PLA2) neutralized the neurotoxicity of this venom and its crotoxin. In this study, we examined the ability of these antisera to neutralize the neurotoxicity of Crotalus durissus terrificus and Bothrops jararacussu venoms and their major toxins, cdt-crotoxin and bothropstoxin-I (BthTX-I), respectively, in mouse isolated phrenic nerve-diaphragm preparations. Immunoblotting showed that antiserum to cdc-crotoxin recognized cdt-crotoxin and BthTX-I, while antiserum to cdc-PLA2 recognized cdt-PLA2 and BthTX-I. ELISA corroborated this cross-reactivity. Antiserum to cdc-crotoxin prevented the neuromuscular blockade caused by C. d. terrificus venom and its crotoxin at a venom/crotoxin:antiserum ratio of 1:3. Antiserum to cdc-PLA2 also neutralized the neuromuscular blockade caused by C. d. terrificus venom or its crotoxin at venom or toxin:antiserum ratios of 1:3 and 1:1, respectively. The neuromuscular blockade caused by B. jararacussu venom and BthTX-I was also neutralized by the antisera to cdc-crotoxin and cdc-PLA2 at a venom/toxin:antiserum ratio of 1:10 for both. Commercial equine antivenom raised against C. d. terrificus venom was effective in preventing the neuromuscular blockade typical of B. jararacussu venom (venom:antivenom ratio of 1:2), whereas for BthTX-I the ratio was 1:10. These results show that antiserum produced against PLA2, the major toxin in C. durissus cascavella venom, efficiently neutralized the neurotoxicity of C. d. terrificus and B. jararacussu venoms and their PLA2 toxins.  相似文献   
110.
Whereas the presynaptic action of Crotalus durissus terrificus venom is well-established, Bothrops venoms have historically been considered to have only postsynaptic and muscular effects. However, some studies have also suggested a presynaptic action for these venoms. In this work, we used chick biventer cervicis preparations to compare the presynaptic actions of two Bothrops venoms (B. insularis and B. neuwiedi) with that of C. d. terrificus venom. At 10 microg/ml, all venoms produced irreversible blockade of the twitch tension responses, with no reduction in acetylcholine (ACh)-induced contractures and only a slight decrease in potassium induced-contractures. The times (in min) required to produce 50% neuromuscular blockade (C. d. terrificus: 16.3+/-0.7, n = 8; B. insularis: 30.0+/-1.9, n = 5; B. neuwiedi: 42.0+/-2.0, n = 8; mean +/- SEM) were significantly different among the venoms (p < 0.01). Lowering the temperature at which the experiments were done (from 37 to 24 degrees C) prevented neuromuscular blockade by the three venoms, indicating that enzyme activity may be involved in this response. At concentrations capable of causing complete neuromuscular blockade, creatine kinase release remained close to levels seen in control preparations incubated with Krebs solution alone (500-1200 IU/l). Commercial crotalic antivenom, but not bothropic antivenom, protected against the neuromuscular blockade caused by B. insularis and B. neuwiedi venoms. These observations indicate that bothropic venoms may contain components which act presynaptically in a manner similar to C. d. terrificus venom, and that at low venom concentrations a direct action on skeletal muscle does not contribute to this presynaptic neurotoxicity.  相似文献   
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