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101.
A Honda G Salen LB Nguyen G Xu GS Tint AK Batta S Shefer 《Canadian Metallurgical Quarterly》1998,27(1):154-159
BACKGROUND: Sclerosing peritonitis (SP) is a rare but serious complication of peritoneal dialysis (PD). Small-bowel obstruction (SBO) due to encapsulation, dense adhesions, or mural fibrous is characteristic, often associated with peritonitis. The aim of the study was to determine the incidence, clinical features, effect of duration of dialysis, and other possible aetiological factors in severe SP. METHODS: All dialysis units in Australia were surveyed for possible cases up to 1994. Patients were included if there was either surgical or radiological evidence of sclerosing encapsulating peritonitis or SBO with tanned or thickened peritoneum in the absence of other causes of SBO. RESULTS: Fifty-four patients were analysed. The duration of continuous PD was mean 52 +/- 30 months, median 48 months and range 8-127 months. Nineteen cases were diagnosed between 1980 and 1989 and 35 between 1990 and 1994, giving mean annual incidences 1.9 and 4.2 per 1000 PD periods respectively. The overall prevalence was 0.7%, which increased progressively with the duration of PD being 1.9, 6.4, 10.8, and 19.4% for patients on dialysis for > 2, 5, 6 and 8 years respectively. Sclerosing encapsulating peritonitis was diagnosed in 87% of cases, SBO in 92%, and haemoperitoneum in 8%. Peritoneal calcification was present in seven cases, all of which had been on PD > 7 years. Peritonitis was associated with 38% of cases with fungal infection in 7%. Treatment with immunosuppression in five patients appeared to result in a favourable outcome in three. The mortality rate was 56%. CONCLUSION: Severe sclerosing peritonitis is a serious complication of peritoneal dialysis and there is a time dependent increase on CAPD. 相似文献
102.
Salival and serum melatonin levels after melatonin ingestion were measured by gas chromatography-mass spectrometry. Ingestion of 3 mg melatonin caused a marked increase in serum melatonin (3561+/-1201 pg/mL) within 20 min, followed by a gradual decrease, but the level still remained higher than the basal level at 240 min after the ingestion. The saliva melatonin 60 min after the ingestion showed the highest level (1177+/-403 pg/mL) which was one-third of the plasma level. The saliva melatonin level was highly correlated with the serum level throughout the experimental period (r=0.82, P=0.0001). These data indicate that the measurement of saliva melatonin level may be a suitable indicator for the melatonin secretion into general circulation. 相似文献
103.
X Yang HR Stennicke B Wang DR Green RU J?nicke A Srinivasan P Seth GS Salvesen CJ Froelich 《Canadian Metallurgical Quarterly》1998,273(51):34278-34283
Granzyme B (GrB) is predicted to trigger apoptosis by activating preferred caspases, but the zymogens that are directly processed by the granzyme and the requirements for these interactions remain unclarified. We examined this dilemma by comparing the kinetics and pattern of GrB-mediated activation of the executioner caspase-7 in vitro and in vivo. GrB rapidly activates procaspase-7 in vitro by cleaving between the large and small subunits leaving the propeptide intact. During GrB-mediated apoptosis, the caspase-7 propeptide is removed and cleavage occurs between the subunits. Strikingly, caspase-7 is unprocessed in caspase-3-deficient MCF-7 cells exposed to GrB but is rapidly activated when the cells are solubilized. Transfection with caspase-3 restores the removal of the caspase-7 propeptide and the capacity of GrB to subsequently activate the caspase. The data suggest that GrB activates caspase-3, which then removes the propeptide of caspase-7 allowing activation by GrB. Thus GrB initiates the death pathway by processing the accessible caspase-3, and the caspase-7 propeptide regulates trans-activation of the zymogen by granzyme. As a consequence, two proteases, caspase-3 and GrB, are required to activate procaspase-7. 相似文献
104.
105.
Talectomy is recommended as a primary or salvage procedure for management of rigid or recurrent equinovarus deformity in arthrogryposis. Twenty-one feet (11 children) that had undergone talectomy were reviewed at a mean follow-up of 11.1 years (range, 2-24). Fourteen (73.7%) feet were satisfactory at final review, whereas five (26.3%) had an unsatisfactory result. Attention to technical details and accurate positioning of calcaneus in the ankle mortise are the two important prerequisites to guarantee a satisfactory long-term result. Fusion of the tibiocalcaneal articulation in optimal position, either spontaneous or induced, is a favorable sign, as it ensures lasting correction of the deformity. The role of a tight and fibrotic tibialis anterior in causing recurrence of severe forefoot adduction and supination is discussed. 相似文献
106.
107.
We investigated the late negative components of the contingent negative variations (CNVs) in the verbalization task. Six subjects were instructed to perform three different motor tasks, jaw opening, vocalization of a meaningless sound and that of a word, in response to a sound stimulus following a visual warning stimulus with interstimulus interval of 4.0 sec. The electroencephalograms (EEGs) were recorded from the midline-central (Cz), left and right temporal areas (T3 and T4) and frontal areas (F7 and F8). EEGs were averaged 16 times using the visual stimulus pulse as a trigger to obtain the CNVs in each motor task. There was no significant difference between the tasks of the jaw opening and vocalization of the sound in the CNV amplitudes at bilateral electrodes. However, the amplitudes of the CNVs at the left frontal and temporal areas were significantly larger in the case of vocalization of the word than in that of jaw opening (p < 0.05). On the other hand, there was no significant difference between these two tasks in the CNV amplitudes at the right frontal and temporal areas. Our results suggested that the CNVs generated over the left hemisphere might reflect the brain activities involved in language production. 相似文献
108.
AIM: To study pharmacokinetics of tablet huperzine A (Hup-A) in Chinese volunteers to help establishing its drug administration schedule. METHODS: For 6 volunteers after a single oral dose of 0.99 mg, drug concentrations in plasma were assayed by reverse phase high pressure liquid chromatography (HPLC) at 0.5, 0.75, 1.0, 1.25, 1.5, 2, 4, 6, 8, and 10 h. The pharmacokinetic parameters were calculated with a 3P87 program by computer. RESULTS: The time course of plasma concentrations conformed to a one-compartment open model with a first order absorption. The pharmacokinetic parameters were as follows: T 1/2ka = 12.6 min, T 1/2ke = 288.5 min, Tmax = 79.6 min, Cmax = 8.4 micrograms L-1, AUC = 4.1 mg L-1 min. CONCLUSION: Hup-A was absorbed rapidly, distributed widely in the body, and eliminated at a moderate rate. 相似文献
109.
Antimicrobial activity of a conjugate based on two antibiotics, i.e. ristomycin A and polymyxin B was studied. The conjugate was shown to have a broad antimicrobial spectrum. In concentrations of 5 to 30 micrograms/ml it inhibited the growth of gram-positive and gram-negative bacteria and in concentrations of 5 to 40 micrograms/ml it inhibited the growth of the pathogenic clinical strains. An insignificant membranolytic action of the conjugate with respect to membranes of the susceptible bacteria and no hemolytic action on human red blood cells were detected. 相似文献