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71.
A significant increase in urine arylsulfatase A activity (p less than 0.01) was found in patients with urothelial tumors. Arylsulfatase A activity was 1.36 +/- 1.10 U/24-h urine in control specimens, 1.90 +/- 1.66 U/24-h urine in various genitourinary tract disorders, and 3.90 +/- 1.98 U/24-h urine in transitional cell carcinoma specimens. Surgical treatment of the neoplastic patients lowered the arylsulfatase A activity found in urine to within reference values. The arylsulfatase A excreted by patients with these tumors was highly sensitive to thermal inactivation while the enzyme activity in the control urines was less affected by the heat treatment. The time course of the arylsulfatase A reaction with 4-nitrocatechol sulfate was not linear in normal individuals, while it was linear in 90% of patients with urothelial tumors. This difference in the kinetic pattern of the enzyme could be used to increase the diagnostic specificity of the determination.  相似文献   
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The SENCAR (sensitive to carcinogenesis) mouse is a unique tool for investigating the interaction between a specific defect in intracellular signaling, dietary calcium, and metabolic bone disease. The SENCAR mouse was developed by selective breeding for enhanced sensitivity to two-stage carcinogenesis. Its major genetic defect, which renders it exquisitely sensitive to stimulation with diacylglycerol or phorbol esters, is in the regulatory domain of protein kinase C, one of the primary intracellular mediators of hormonal effects. At sexual maturity, SENCAR mice are large and have big bones, but our previous pharmacokinetic studies showed that they accumulate lesscalcium under normal conditions and lose more calcium under adverse conditions than do other, standard strains of mice. To histologically define the effect of low dietary calcium on bone metabolism, we performed histomorphometric analysis of tetracycline-labeled sections of femoral bone from male SENCAR mice maintained on calcium-sufficient and calcium-deficient diets during the critical period from 10 to 14 weeks of age. The bone volume, absolute osteoid volume, and mineral apposition rate were lower at 14 than at 10 weeks of age in SENCAR mice fed 0.02 or 0.6% calcium diets. Calcium deficiency increased the architectural disarray and the probability of observing focal discontinuities in the growth plate. Thus, characteristic features of impaired bone metabolism (low bone volume and apposition rate) develop early in SENCAR mice and are exacerbated by low dietary calcium. Detailed examinations of the histology and biochemistry of SENCAR mouse bone will provide insights into the mechanisms by which specific defects in the signal transduction of protein kinase C contribute to impaired bone metabolism.  相似文献   
74.
Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia.  相似文献   
75.
We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients.  相似文献   
76.
The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short‐ and long‐term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post‐surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important.  相似文献   
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Objective: To determine the effects of a total laryngectomy on the swallow and subsequent quality of life in head and neck cancer patients. Design: Cross‐sectional single centre cohort study. Setting: Head and Neck Oncology Unit, Tertiary Referral Unit. Patients: Sixty‐two patients who underwent total laryngectomy at our centre participated in the study. Methods: Subjects were stratified by age, sex, tumour stage, other procedures such as myotomy and nerve re‐implantation. Pharyngectomy, glossectomy, flap reconstruction, neck dissection and previous radio‐ and chemotherapy were also assessed to see if they affected swallow and subsequent quality of life. Main outcome was measured using the MD Anderson Dysphagia Inventory questionnaire. Results: Responses were received from 46 males and 16 females (response rate of 80.5%) with a mean age of 64.7 years (SD 9.4). Median follow‐up in patients was 90 months (range 1–276). The mean MD Anderson Dysphagia Inventory total score in our series of patients was 77.7 (SD 16.6). MD Anderson Dysphagia Inventory global score was 79.4 (SD 22.6), Emotional score was 77.7 (SD 17.8), Functional score 81.3 (SD 15.9) and Physical score was 74.1(SD 18). Statistically significant differences were seen between the emotional scores of glossectomised and non‐glossectomised patients (Mann Whitney, P = 0.04). No significant correlation was seen between the subscale scores and the remaining treatment variables such as age, gender, site, tumour stage, myotomy, nerve implantation, radiotherapy, reconstruction and major complications. Conclusion: This questionnaire study is the largest of its type to assess the swallow of patients who have undergone laryngectomy at a single centre. The overall result confirmed that most patients had a subjectively good swallow. Only glossectomy and the method of PE segment closure were shown to significantly affect swallowing outcomes following surgery. We recommend further work especially prospective studies pre and post surgery using this or similarly validated instruments to fully assess swallow in the laryngectomy population.  相似文献   
80.
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