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991.
992.
Intra- and interpersonal interlimb coordination of pendulums swung from the wrist was investigated. For both kinds of coordination, the steady state and breakdown of bimanual rhythmic coordination as indexed by the time series of the relative phase angle phi were studied under the manipulation of coordination mode, frequency of oscillation, and the difference in the eigenfrequencies (preferred tempos) of the individual oscillating limbs. The properties observed for both intra- and interpersonal coordination were those predicted by a dynamical model of rhythmic coordination that considers the coordinated limbs coupled to be nonlinear oscillators. Using a regression method, the coupling strengths of the coupled system were recovered. As predicted by the dynamical model, the strength of the dynamic was generally greater for the in-phase than the anti-phase mode and decreased with increasing frequency. Further, the strength of the interpersonal interlimb coupling was weaker than that of intrapersonal interlimb coupling.  相似文献   
993.
BACKGROUND: Chiropractic spinal manipulation has been reported to be of benefit in nonmusculoskeletal conditions, including asthma. METHODS: We conducted a randomized, controlled trial of chiropractic spinal manipulation for children with mild or moderate asthma. After a three-week base-line evaluation period, 91 children who had continuing symptoms of asthma despite usual medical therapy were randomly assigned to receive either active or simulated chiropractic manipulation for four months. None had previously received chiropractic care. Each subject was treated by 1 of 11 participating chiropractors, selected by the family according to location. The primary outcome measure was the change from base line in the peak expiratory flow, measured in the morning, before the use of a bronchodilator, at two and four months. Except for the treating chiropractor and one investigator (who was not involved in assessing outcomes), all participants remained fully blinded to treatment assignment throughout the study. RESULTS: Eighty children (38 in the active-treatment group and 42 in the simulated-treatment group) had outcome data that could be evaluated. There were small increases (7 to 12 liters per minute) in peak expiratory flow in the morning and the evening in both treatment groups, with no significant differences between the groups in the degree of change from base line (morning peak expiratory flow, P=0.49 at two months and P=0.82 at four months). Symptoms of asthma and use of 3-agonists decreased and the quality of life increased in both groups, with no significant differences between the groups. There were no significant changes in spirometric measurements or airway responsiveness. CONCLUSIONS: In children with mild or moderate asthma, the addition of chiropractic spinal manipulation to usual medical care provided no benefit.  相似文献   
994.
A series of novel selective phosphodiesterase 4 (PDE4) inhibitors has been developed which displays activity both in vitro and in vivo. These compounds possess good selectivity for the catalytic site of PDE4 over the high affinity Rolipram binding site. In vivo studies demonstrate a reduced propensity to display the emetic side effects which are commonly observed with PDE4 inhibitors.  相似文献   
995.
Three patients with chronic heart failure, men aged 29, 78 and 69 years, developed severe dyspnoea and oedema in spite of reduced sodium and fluid intake and medication including furosemide. Heart failure may become 'resistant to diuretics' due to pharmacokinetic and pharmacodynamic causes. High-dose continuous intravenous administration of a loop diuretic may afford relief in such cases, if necessary in combination with a thiazide derivative, an ACE inhibitor, an inotropic agent or an extracorporal technique. Monitoring and correction of the state of hydration of a patient with chronic heart failure may improve the prognosis and the quality of life.  相似文献   
996.
Cytotoxicities induced by 1,1-dichloroethylene (DCE) are ascribed to cytochrome P450-dependent metabolism to an epoxide. Conjugation of the DCE-epoxide with glutathione (GSH) results in the formation of the conjugates 2-S-glutathionyl acetate (GTA) and 2-(S-glutathionyl) acetyl glutathione (GAG); GAG undergoes hydrolysis to form GTA, and thus GTA is a major metabolite of DCE metabolism. Our objective is to develop an antiserum against the chemically synthesized GTA, and for immunization, we have used a hapten that consists of GTA conjugated to bovine serum albumin (BSA) as the carrier protein and glutaraldehyde (GLUT) as a chemical cross-linker. The antisera were raised in rabbits and were characterized by using the following synthesized structural analogs: GTA, glycine-GLUT-BSA (GLY-GLUT-BSA), GTA-GLUT-ovalbumin (GTA-GLUT-OVB), GTA-1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-BSA (GTA-EDC-BSA), TRIS-GLUT-BSA, glutathione-GLUT-BSA (GSH-GLUT-BSA). The enzyme-linked immunosorbent assay (ELISA) and slot immunoblotting were used to characterize the specificity of the antisera. Noncompetitive ELISA experiments showed that the reaction of the antiserum with the antigen was concentration-dependent. In the competitive ELISA, GTA-GLUT-BSA inhibited binding efficiently; in contrast, the unconjugated GTA did not inhibit binding to the antigen. Competitive studies with the other analogs indicated low or minimal reactivities with the antibodies, which were blocked by incubation with GLY-GLUT-BSA. However, there was residual reactivity with the antigen that was not competitively inhibited by either the GTA-EDC-BSA or the GSH-GLUT-BSA conjugates. Slot-blotting experiments confirmed the findings of the ELISA studies and revealed high specificity of the antiserum to detect the hapten. These results demonstrated the successful development of polyclonal antibodies to detect GTA and hence DCE-epoxide.  相似文献   
997.
PURPOSE: A multicenter trial of chemoradiation therapy to evaluate the feasibility of extended field radiation therapy (ERT) with 5-fluorouracil (5-FU) and cisplatin, and to determine the progression-free interval (PFI), overall survival (OS), and recurrence sites in patients with biopsy-confirmed para-aortic node metastases (PAN) from cervical carcinoma. METHODS AND MATERIALS: Ninety-five patients with cervical carcinoma and PAN metastases were entered and 86 were evaluable: Stage I--14, Stage II--40, Stage III--27, Stage IVA--5. Seventy-nine percent of the patients were followed for 5 or more years or died. ERT doses were 4500 cGy (PAN), 3960 cGy to the pelvis (Stages IB/IIB), and 4860 cGy to the pelvis (Stages IIIB/IVA). Point A intracavitary (IC) doses were 4000 cGy (Stages IB/IIB), and 3000 cGy (Stages IIIB/IVA). Point B doses were raised to 6000 cGy (ERT + IC) with parametrial boost. Concomitant chemotherapy consisted of 5-FU 1000 mg/m2/day for 96 hours and cisplatin 50 mg/m2 in weeks 1 and 5. RESULTS: Eighty-five of 86 patients completed radiation therapy and 90% of patients completed both courses of chemotherapy. Gynecologic Oncology Group (GOG) grade 3-4 acute toxicity were gastrointestinal (18.6%) and hematologic (15.1%). Late morbidity actuarial risk of 14% at 4 years primarily involved the rectum. Initial sites of recurrence were pelvis alone, 20.9%; distant metastases only, 31.4%; and pelvic plus distant metastases, 10.5%. The 3-year OS and PFI rate were 39% and 34%, respectively, for the entire group. OS was Stage I--50%, Stage II--39%, and Stage III/IVA--38%. CONCLUSIONS: Extended field radiation therapy with 5-FU and cisplatin chemotherapy was feasible in a multicenter clinical trial. PFI of 33% at 3 years suggests that a proportion of patients achieve control of advanced pelvic disease and that not all patients with PAN metastases have systemic disease. This points to the importance of assessment and treatment of PAN metastases.  相似文献   
998.
OBJECTIVE: To evaluate the safety and efficacy of amitriptyline hydrochloride in the treatment of severe recurrent idiopathic cystitis (IC) in cats. DESIGN: Prospective study. ANIMALS: 15 cats with IC that failed to respond to other treatments. PROCEDURE: Each cat received 10 mg of amitriptyline, PO, every 24 hours in the evening for 12 months or until signs recurred. Urinalysis, CBC, serum biochemical analysis, urine bacteriologic culture, and cystoscopy were performed initially, and after 6 and 12 months in responders. Severity scores of owner-observed signs of lower urinary tract (bladder and urethra) disease were recorded. RESULTS: During the first 6 months of treatment, 11 of the 15 cats had no owner-observed signs of lower urinary tract disease. During the next 6 months, 9 of 15 cats remained free of signs of cystitis. Despite clinical improvement, cystoscopic abnormalities persisted in all cats at the 6- and 12-month evaluations. Hematuria and proteinuria were decreased at the 12-month evaluation compared with the initial evaluation. Two of 15 cats initially appeared somnolent after amitriptyline treatment. Of 9 cats completing the study, 7 had increased body weight and 8 had decreased coat quality compared with the initial evaluations. Four cats developed small cystic calculi during the first 6 months of the study. Serum biochemical or hematologic abnormalities were not detected during the study. CLINICAL IMPLICATIONS: Amitriptyline treatment successfully decreased clinical signs of severe recurrent IC in 9 of 15 cats treated. Somnolence, weight gain, decreased grooming, and transient cystic calculi were observed during treatment in some cats.  相似文献   
999.
BACKGROUND: Fetal rhabdomyomatous nephroblastoma (FRN) is a rare variant of Wilms tumor. MATERIALS AND RESULTS: One hundred and thirty two children with kidney tumors were seen at our hospital from 1985 to 1993. Among them were 6 (4.5%) who had FRNs. Five were boys aged 8 months to 3 years; the girl was 17 months old. Three of the four with unilateral disease had tumors so large that they were considered unresectable at diagnosis. Five received pre-operative chemotherapy and three also received pre-operative radiation therapy. None of the tumors responded. Both patients with bilateral tumors died of progressive disease. Three of the four patients with unilateral disease followed for at least one year are alive for 1 to 10 years after diagnosis. CONCLUSIONS: FRN should be in the differential diagnosis of huge kidney tumors in children, and preoperative therapies escalated with caution since FRN is not responsive to treatment used for classic Wilms tumor.  相似文献   
1000.
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