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91.
92.
The goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc.  相似文献   
93.
Examined are several measures currently used in the assessment of child abuse, sexual abuse, and trauma. These measures include structured clinical interviews, self report measures, screening inventory, symptom checklist, and some measures that include decision making properties. Issues and implications for clinical practice are explored.  相似文献   
94.
We report 2 cases of leiomyosarcoma of the bladder that occurred after long-term cyclophosphamide chemotherapy for lupus nephritis and rheumatoid arthritis. One patient had a tumor at the end of an 11-year course of chemotherapy and 1 approximately 7 years after completing a 7-year course of chemotherapy. Patient 1 underwent left partial cystectomy and patient 2 underwent cystectomy with ileal conduit urinary diversion. In patient 1 the tumor was a typical leiomyosarcoma and patient 2 had a myxoid variant. Both patients were free of disease at 4 months and 3 years, respectively. Whereas previous reports of the carcinogenic effects of cyclophosphamide have been questioned, since the induced tumors occurred in patients being treated for other neoplasms (lymphoproliferative and myeloproliferative disorders), the disease in both of our patients followed cyclophosphamide therapy for nonneoplastic disorders.  相似文献   
95.
The ileal neobladder produces a completely detubularized, low pressure, high capacity reservoir constructed from ileum without any valves. From April 1986 through May 1989, 113 patients underwent this procedure at our institution. Of these patients 99 underwent simultaneous radical cystectomy for bladder cancer and 14 underwent bladder augmentation. The mean postoperative followup was 14.4 months, with a range of 1 to 36 months. There was no perioperative mortality. However, 7 patients died more than 2 months postoperatively: 5 of tumor progression, 1 of pneumonia and severe metabolic acidosis, and 1 of septicemia of unknown cause. Reoperation was necessary in only 13 patients; 10 patients required urethrotomy or dilation of urethral strictures. Day and night continence was preserved in 82.1% of all patients. Stress incontinence, which must be corrected by an artificial sphincter, was found in 4 patients (4.2%) and night-time incontinence that required an external device occurred in 5 (5.3%). Eight patients (8.4%) with mild stress incontinence required no further treatment. Pressure waves exceeding 22 cm. water seldom occurred and then only at maximum capacity. Our experience with this relatively simple system without a nipple is an overwhelming success. The need for reoperation is extraordinarily low and the high reservoir capacity results in continence from the beginning in most patients. The concept is sound and offers a genuine alternative to any form of cutaneous urinary diversion with an incidence of complications not higher than after standard supravesical urinary diversion.  相似文献   
96.
Nutritional selenium deficiency disease, due to low soil selenium content, is well recognized in British livestock. The adequacy of the selenium status of 25 healthy human volunteers, 50 blood donors, 94 general medical patients and 106 allergy clinic patients was investigated in 1987/8 by measuring serum selenium concentration and platelet glutathione peroxidase activity. Mean serum selenium concentration for the entire study population was 92 micrograms/l. Significant linear correlations between serum selenium concentration and peroxidase activity indicate that a substantial proportion of both healthy volunteers and medical patients are of low selenium nutritional status. Twenty-five per cent of healthy volunteers and 50 per cent of medical patients had serum selenium values below those required for full expression of selenium-dependent enzyme activity. Deficiency of the antioxidant activities of selenium and selenium-dependent enzymes may be relevant to geographical differences in morbidity from a wide range of human disease states.  相似文献   
97.
The objective of this study was to determine whether the development of tolerance to CP 55,940, a potent cannabinoid agonist, was due to changes in the receptor or second messenger system. ICR mice treated with CP 55,940 (2 mg/kg) twice a day for 6 and one-half days developed a high degree of tolerance to the pharmacological effects of CP 55,940. The ability of CP 55,940 to produce motor hypoactivity, hypothermia and immobility was reduced 163-, 97- and 19-fold, respectively. Evaluation of 3H-CP 55,940 binding to rat brain membranes indicated no difference in receptor affinity between the vehicle- and CP 55,940-treated animals. However, these binding studies revealed a 50% decrease in receptor number in the cerebellum of the CP 55,940-tolerant mice. Although cAMP is generally considered to be the second messenger for cannabinoid receptors, little difference was observed in the inhibitory effects of CP 55,940 on adenylyl cyclase activity in cerebellum between vehicle and drug-treated mice. However, there was an increase in receptor mRNA which suggests a compensation for receptor loss. There are several possible explanations for these results. There may be sufficient spare receptors such that CP 55,940-tolerant mice are capable of producing a maximal effect on the second messenger system. On the other hand, one could conclude that cannabinoid receptor down-regulation does not account for the development of tolerance to all of the effects of CP 55,940 in mice.  相似文献   
98.
Abstract Bleeding on probing (BOP) and the gingival index have been used to clinically characterize the degree of gingival inflammation. It is, however, unclear to what extent these parameters correlate to each other and to probing pocket depth (PD). The purpose of this clinical study was to evaluate the association between BOP and GI bleeding (scores of 2 and 3), as well as the relationship of these variables to PD, in a group of patients presenting with naturally-occurring gingivitis. Based on screening examinations of 125 subjects with at least 20 teeth, no more than 4 sites with PD over 6 mm, a BOP frequency of 30% or greater, and no systemic condition that would influence the inflammatory response, were selected. 2 weeks after screening they were examined at 6 sites per tooth for plaque index, GI, PD and BOP. A standardized pressure sensitive probe (Florida Probe) with 20 g probing force was used for BOP and PD measurements. In this population, means of 40.9% (S.E.= 1.36) BOP sites and 35.3% (S.E, = 1.81) GI bleeding sites per patient were found. A total of 20,008 sites ranging in PD up to 5.9 mm were evaluated; however, the majority of sites (19,723, 98.6%) presented with <4 mm PD. When sites were evaluated, BOP demonstrated a positive correlation with PD, whereas GI bleeding correlated with PH. For sites characterized by the absence of BOP as well as the absence of GI bleeding (scores 0 and 1), the highest % of agreement between the 2 indices (77.7%) was found in shallow sites (0.1–2 mm). In contrast, when sites presenting with both BOP and GI bleeding were analyzed, the highest % of agreement (85,4%) was found for sites with PD >4.0 mm. In this gingivitis population group, it appears that BOP and GI bleeding evaluate distinct inflammatory1 conditions of the gingival tissues, and the relationship between the 2 clinical parameters may vary according to PD at the individual site examined.  相似文献   
99.
A series of tylosins and acyl derivatives of 23-O-demycinosyltylosin (DMT) were initially tested for in vitro antibacterial activity and serum levels in squirrel monkeys (po) and mice (iv). Overall, the DMT compounds were more active in vitro than the tylosins. Two tetraacylated DMTs, Sch 37644 and Sch 38646, were selected from the initial studies for further evaluation and compared to erythromycin and A-56268 (6-O-methyl erythromycin). Sch 37644 and Sch 38646 were 2 to 8-fold less potent in vitro against Gram-positive bacteria than erythromycin and A-56268. In squirrel monkeys, Sch 37644 (AUC, 19.7 micrograms.hour ml) and A-56268 (21.6 micrograms.hour/ml) had similar serum levels following po administration of 20 mg/kg, while Sch 38646 (11.8 micrograms.hour/ml) and erythromycin (1.5 micrograms.hour/ml) had lower levels. In mice administered 200 mg/kg orally, Sch 37644 (AUC, 19.4 micrograms.hour/ml) and Sch 38646 (15.4 micrograms.hour/ml) had higher serum levels than erythromycin (5.7 micrograms.hour/ml). A-56268 was the most active po macrolide in mouse protection studies (PD50S) against Staphylococci and Streptococci, while Sch 37644 and Sch 38646 were similar to erythromycin.  相似文献   
100.
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