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21.
The authors conducted a retrospective analysis of 1178 patients with histologically proven invasive carcinoma of the uterine cervix treated with irradiation alone. The minimum follow-up time was 3 years. The 10-year actuarial pelvic failure rate in Stage IB was 6% for tumors less than 3 cm, 15% for tumors 3 to 5 cm, and 30% for tumors more than 5 cm (P = 0.0018). The 10-year actuarial pelvic failure rate in Stage IIA was 10% for tumors less than 3 cm, 28% for tumors 3 to 5 cm, and 20% for tumors more than 5 cm (P = 0.09). Stage IIB unilateral nonbulky tumors (less than 5 cm) had a 20% pelvic failure rate compared with 28% for bilateral lesions and 35% for unilateral bulky tumors (more than 5 cm) (P = 0.35). In Stage IIB, pelvic failures were greater when disease extended into the lateral parametrium (30%) compared with medial parametrial involvement only (17%) (P = 0.01). In Stage III unilateral nonbulky tumors, the pelvic failure rate was 28% compared with 45% to 50% for unilateral bulky lesions (P = 0.002). Bilateral parametrial disease in Stage IIB did not increase the pelvic failure rate (21% in both subgroups) (P = 0.83), whereas in Stage III, bilateral parametrial involvement was associated with a 48% pelvic failure rate versus 28% for unilateral extension (P less than or equal to 0.01). Five-year disease-free survival (DFS) rates for IB tumors less than or equal to 3 cm was 90% versus 67% for tumors more than 3 cm (P = 0.01). In Stage IIA tumors less than or equal to 3 cm, 5-year DFS was 70% versus 45% for tumors more than 3 cm. Patients with Stage IIB nonbulky tumors (less than or equal to 5 cm in diameter) had better 10-year DFS (65% to 70%) compared with those with bilateral bulky tumors (45% to 55%) (P = 0.10). Stage III patients with unilateral nonbulky tumors had a 55% 10-year DFS compared with 35% to 40% for bulky tumors or bilateral parametrial involvement (P = 0.002). The authors concluded that clinical stage and size of tumor are critical factors in the prognosis, therapy selection, and evaluation of results in carcinoma of the uterine cervix.  相似文献   
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BACKGROUND: In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. MATERIAL/METHODS: Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. RESULTS: Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. CONCLUSIONS: These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities.  相似文献   
23.
A rapid, simple, quantitative and sensitive assay for the determination of 5'-nucleotidase has been developed. The method can be applied to both soluble and membrane bound forms of the leukocyte enzyme. Enzyme activity is determined by colorimetric estimation of NH3 released from adenosine, the product of 5'-nucleotidase activity in the presence of adenosine deaminase. The assay may be performed in microtitre plates and read with an automatic multiscan spectrophotometer. Thus it can be applied to a large number of samples for routine medical and research purposes.  相似文献   
24.
To incorporate family therapy into an inpatient treatment program for spinal cord injured substance abusers required overcoming both staff and patient resistance. Since it became an integral part of the program, family therapy has shown itself to be helpful in dealing with this population's tendency to adapt to their injury either by overdependency or overachievement. Its usefulness to patients with other chronic disabilities appears to warrant consideration.  相似文献   
25.
The role of catecholaminergic mechanisms in determining the changes in the rat's preoptic cyclic adenosine monophosphate (cAMP) concentration during sleep deprivation and recovery induced by ambient temperature was investigated in the present study. To this end, the activity of tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, was measured in the preoptic region of rats maintained in: (a) control (22 degrees C for 52 h), (b) deprivation (-10 degrees C for 52 h), and (c) recovery (22 degrees C for 4 h after 48 h at -10 degrees C) conditions. The enzyme followed a Michaelis-Menten kinetic. The analysis of substrate-related kinetic parameters (Km and Vmax) did not show any clear-cut difference between experimental conditions, which, as already known, induce both sleep deprivation and recovery in relation to significant cAMP changes.  相似文献   
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The impact of laparoscopic (lap) live donor nephrectomy on early graft function and survival remains controversial. We compared 2734 kidney transplants (tx) from lap donors and 2576 tx from open donors reported to the U.S. United Network for Organ Sharing from 11/1999 to 12/2000. Early function quality (>40 mL urine and/or serum creatinine [creat] decline >25% during the first 24 h post-tx) and delayed function incidence were similar for both groups. Significantly more lap (vs. open) txs, however, had discharge creats greater than 1.4 mg/dL (49.2% vs. 44.9%, p = 0.002) and 2.0 mg/dL (21.8% vs. 19.5%, p = 0.04). But all later creats, early and late rejection, as well as graft survival at 1 year (94.4%, lap tx vs. 94.1%, open tx) were similar for lap and open recipients. Our data suggests that lap nephrectomy is associated with slower early graft function. Rejection rates and short-term graft survival, however, were similar for lap and open graft recipients. Further prospective studies with longer follow up are necessary to assess the potential impact of the laparoscopic procurement mode on early graft function and long-term outcome.  相似文献   
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