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The antigenic constituents of sporulated Cryptosporidium parvum oocyst antigens were characterized with antisera from mice immunized against C. parvum. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver staining defined the major proteins. Six of seven lectins used recognized as many as 15 bands. The lectins concanavalin A, Dolichos biflorus, and wheat germ agglutinin showed strong activity against the same eight bands with molecular weights ranging from 72,000 to greater than 100,000. An enzyme-linked immunosorbent assay was used to detect antibody to C. parvum. Antibody binding was significantly decreased by heat and enzymatic treatment with trypsin, protease, and mixed glycosidases. C. parvum antigens were further defined by the reactivity of immune sera with a C. parvum sonicate preparation separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrophoretically transferred to nitrocellulose paper. Antisera from orally infected mice consistently recognized four antigens with molecular weights ranging from 72,000 to greater than 100,000. These antigens also bound concanavalin A. Treatment of the antigen preparation with mixed glycosidases reduced the reactivity of antisera with most antigens with molecular weights greater than 60,000. The data suggest that the antigenic composition of C. parvum is complex and that carbohydrates alone or in association with lipids or proteins may be important in the immune response to C. parvum.  相似文献   
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Although the nephrotoxic side effects of cyclosporine are well known, the impact of long-term CsA on renal transplant function is uncertain. We studied 5-10-year renal function in 347 CsA-treated patients, and in 64 randomly selected non-CsA-treated patients who had a minimum of 55 months of graft function. Non-CsA patients had a lower creatinine (Cr) level at one year than CsA patients (P = .001), with no change in renal function over time (P = .6). In CsA-treated patients there was also no suggestion of progressive renal damage, as evidenced by no change in Cr or 1/Cr. Simple linear regression models of 1/Cr vs. time for the first 10 years posttransplant were fit to the data for each patient. Analysis of the Y-intercept estimates from these regressions showed that age (P = .001), sex (P = .001), cyclosporine toxicity (P = .024), and initial cyclosporine dosage (P = .016) significantly affected the one-year serum Cr. Variables not affecting one-year Cr included donor source, early rejection episodes, late rejection episodes, ATN, diabetes, transplant number, HLA ABDR mismatch (for cadaver transplants), maximum PRA, and PRA at transplant. Analysis of the slope estimates from the regressions revealed that only age (P = .001) and late rejection episodes (P = .001) significantly affected the rate of change in 1/Cr over time. We conclude that, in long-term renal transplant patients, there is no evidence of progressive deterioration in renal function due to CsA nephrotoxicity.  相似文献   
25.
Nephro-ureterectomy is the standard treatment for transitional carcinoma of the renal pelvis and caliceal system. In recent years a modification of the conventional two-incision technique has been described in which the intramural ureter is resected endoscopically and the remaining ureter is removed in continuity with the kidney through a single loin incision. Twenty-one patients had their renal pelvic tumours treated by this modified technique between 1970 and 1983. Of 16 patients available for analysis, 37.5% subsequently developed bladder tumours. It was concluded that this modified technique has no greater incidence of subsequent bladder tumour development than the conventional technique of nephro-ureterectomy, whilst giving considerable benefit to the patient.  相似文献   
26.
The effectiveness of fibrin glue as a biological sealant for pulmonary air leaks was determined in 16 dogs. A standardized pleural defect was made in the left lower lobe, and the quantity of air passing through a chest tube was assessed with a Collins respirometer. For the 8 randomly assigned control animals, the air leak decreased over 90 minutes from a mean of 1.4 L/min to a mean of 1.1 L/min (mean decrease, 19.8%). In the 8 randomly assigned fibrin glue-treated animals, the air leak decreased from a mean of 2.1 L/min to a mean of 0.5 L/min (mean decrease, 80.8%) (p less than 0.0001). Postoperative evaluation of survivors disclosed no increased adhesions in the glue-treated animals and complete resorption of the glue at 3 months. We conclude that in this animal model, fibrin glue reduced the size of pulmonary air leaks in the early period after thoracotomy and did not lead to increased intrapleural adhesions.  相似文献   
27.
Completion pneumonectomy: indications, complications, and results   总被引:9,自引:0,他引:9  
From 1958 through 1985, a total of 113 consecutive patients had completion pneumonectomy (CP). Indications for pulmonary resection resulting in CP were lung cancer (LC) in 64 patients, pulmonary metastases (PM) in 20, and benign lung disease (BLD) in 29. Operative mortality was 12.4% (14 deaths) but varied according to the indication for CP. Mortality was 9.4% for LC, 0% for PM, and 27.6% for BLD. Forty-three patients (38.1%) had major complications (26 of 64 with LC, 40.6%; 1 of 20 with PM, 5.0%; and 16 of 29 with BLD, 55.2%). Five-year actuarial survival for patients with LC was 26.4% but varied according to stage. Five-year survival for patients with PM was 40.8% and with BLD was 27.2%. We conclude that CP for BLD carries marked operative mortality and morbidity, usually due to intense reaction around hilar structures and concurrent active infection or fistula. In contrast, CP for LC and PM can be performed with low mortality, acceptable morbidity, and gratifying long-term survival.  相似文献   
28.
PURPOSE: Following ambulatory surgery, long-acting analgesics may provide advantages over short-acting analgesics. This study compared controlled-release codeine (CC) and acetaminophen plus codeine (A/C; 300 mg/30 mg) for pain control in the 48-hr period following laparoscopic cholecystectomy. METHODS: Eligible patients were randomized to CC or A/C in a double-blind, double-dummy parallel group study. Unrelieved pain in hospital was treated with fentanyl i.v. bolus. Pain [100 mm visual analogue scale (VAS)] was assessed before the first dose of medication; at 0.5, one, two, three, and four hours post-dose; at discharge; and three times a day for 48 hr. Adverse events were recorded and measures of patient satisfaction were assessed at the end of the study. RESULTS: Eighty-four patients were enrolled in the study; 42 patients in each group. There were no statistically significant differences between CC and A/C treatment. Mean VAS baseline pain was similar in both groups (P = 0.49) and there was no significant difference in the time to onset of analgesia (P = 0.17). At 0.5 hr, the mean VAS pain score was significantly reduced from baseline in both groups (P = 0.0001). The VAS pain scores at discharge were reduced 59% and 56% from baseline, respectively (P = 0.61). There was no difference between treatments in the incidence of adverse events and patients reported similar levels of satisfaction. CONCLUSIONS: Controlled-release codeine provides an equivalent onset of analgesia, reduction in postoperative pain, and level of patient satisfaction, to acetaminophen plus codeine, over 48 hr following cholecystectomy, with the advantage of less frequent dosing.  相似文献   
29.
The involvement of pituitary prolactin (PRL) in systemic vasoactive intestinal peptide (VIP)-induced sleep was studied. Male rats were implanted with electrodes for EEG-recording, with brain thermistors to record cortical temperature (Tcrt) and with chronic intracardial catheters to obtain blood samples and to deliver substances. One group of rats (n = 8) received normal rabbit serum (NS) + physiological saline (SAL) on the baseline day and was injected with NS + VIP on the experimental day. In the other group of rats (n = 6), the baseline day was followed by administration of PRL-antiserum (PRL-AS) + VIP on the experimental day. The sera and VIP or SAL were injected 30 min before and at light onset, respectively. Sleep-wake activity was then recorded for the next 12-h light period. Systemic VIP-stimulated PRL secretion as measured by RIA in serial samples obtained hour 1 postinjection. VIP also elicited selective increases in REM sleep (REMS) in the rats pretreated with NS. Tcrt was not affected by VIP. Administration of PRL-AS blocked the increase in circulating levels of free (non-IgG-bound) PRL and prevented VIP-enhanced REMS. Comparisons of the sleep effects of PRL-AS + VIP with the previously reported changes in sleep after PRL-AS alone indicate that PRL has a major role in the mediation of the REMS-promoting activity of systemic VIP. The results suggest that an increased release of endogenous pituitary PRL modulates REMS.  相似文献   
30.
Hodgkin disease: CT of the thymus   总被引:2,自引:0,他引:2  
Heron  CW; Husband  JE; Williams  MP 《Radiology》1988,167(3):647-651
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.  相似文献   
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