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121.
The inhibition of tomato pectin methylesterase (PME) by a recently discovered kiwi pectin methylesterase inhibitor (PMEI) is described. PME was consequently purified by CM Sephadex C-50, Concanavalin A-Sepharose 4 B and Mono S chromatography, and PMEI by Q-Sepharose and Sephacryl S-200 chromatography. Inhibition of tomato PME activity under optimal conditions (0.125 m NaCl, pH 7.5) by partially purified kiwi PMEI (MW of 27 kD, pI ≥ 3.67) was independent of the PMEI/PME ratio between 36 and 61% of the maximal uninhibited activity. the non-competitive inhibition observed was optimal in the pH range of 5 to 7. PMEI was inactivated by heating to 120°C, and showed actinidin-like activity towards N-α-benzyloxycarbonyl-L-lysine p -nitrophenyl ester (CBZ-lys-ONp) and azocasein which was partially inhibited by the protease inhibitor leupeptin. 相似文献
122.
TW Breen T Shapiro B Glass D Foster-Payne NE Oriol 《Canadian Metallurgical Quarterly》1993,77(5):919-924
The effectiveness of two epidural analgesic regimens on the ability to ambulate was compared in women in labor by a prospective, randomized, double-blind design. One group of patients received epidural fentanyl, a 75-micrograms bolus and an infusion of fentanyl 2.5 micrograms/mL at 15 mL/h (FENT, n = 53). A second group received ultra low-dose bupivacaine (0.04%), epinephrine (1.7 micrograms/mL), and fentanyl (1.7 micrograms/mL) (BEF, n = 77), a 15-mL bolus followed by an infusion at 15 mL/h. Adequate analgesia was rapidly obtained in 90.6% of patients in the FENT group and 92.2% of patients in the BEF group (P = 0.89). Seventy percent of patients in the FENT group ambulated versus 68% in the other group. The BEF mixture provided analgesia of longer duration (287 +/- 171 min versus 156 +/- 72 min, P = 0.0001). The number of patients delivering during administration of only their study drug (without needing higher doses of local anesthetics) was 52% for BEF and 21% for FENT (P = 0.0005). Hip flexion weakness precluding ambulation occurred in 17% (P = 0.002) of BEF patients and orthostatic hypotension in 9% (P = 0.08). Neither problem occurred in FENT patients. Neonatal outcome was similar in both groups. Approximately 70% of women receiving epidural analgesia with fentanyl or ultra low-dose bupivacaine, epinephrine, and fentanyl may ambulate safely during labor. 相似文献
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124.
JE Alpert LA Uebelacker NE McLean AA Nierenberg JA Pava JJ Worthington JR Tedlow JF Rosenbaum M Fava 《Canadian Metallurgical Quarterly》1997,27(3):627-633
BACKGROUND: Increasing attention has been directed in recent years to the detection and treatment of psychiatric co-morbidity among depressed individuals. The overlap of social phobia (SP) and avoidant personality disorder (APD) has been well recognized and a relationship between these disorders and depression has been suggested. METHODS: The pattern and clinical implications of co-morbidity of SP and APD with major depressive disorder (MDD), diagnosed by DSM-III-R criteria, were studied among 243 out-patients presenting with depression. RESULTS: Overall, 26.7% of adults in our sample with MDD met criteria for SP and 28.4% for APD. Almost two-thirds of depressed adults meeting criteria for social phobia or avoidant personality disorder met criteria for both (SP+APD). Depressed adults who met criteria for both SP+APD exhibited a significantly higher proportion of atypical depression (54.8%) compared with those with neither SP nor APD (31.1%). Among depressed patients, the co-occurrence of SP with APD was also associated with an earlier age of onset of MDD, a greater number of comorbid Axis I diagnoses, and greater impairment of social adjustment and assertiveness. CONCLUSIONS: Results confirm the overlap of SP and APD in a depressed population and the high prevalence of these disorders in MDD. They suggest that depressed individuals with both SP and APD but not SP alone are at particularly high risk for atypical depression and for social dysfunction in excess of that caused by a current major depression. 相似文献
125.
126.
NE Avis KW Smith RK Hambleton HA Feldman A Selwyn A Jacobs 《Canadian Metallurgical Quarterly》1996,34(11):1102-1120
OBJECTIVES: The purpose of this study was to design a multidimensional measure of health-related quality of life appropriate for patients with cardiovascular disease that was psychometrically sound, brief, and easy to administer. METHODS: Qualitative interviews conducted with healthy subjects and patients with cardiovascular diseases identified nine major quality of life domains. Based on the responses of 129 cardiovascular disease patients recruited from hospitals and clinics, a criterion-based approach was used to select 35 questionnaire items that best tapped these domains. Psychometric properties of the Multidimensional Index of Life Quality (MILQ) were tested with a sample of 348 patients with various cardiovascular diseases. RESULTS: Cronbach's alpha was 0.76 or higher for eight of the nine MILQ domains. Test-retest reliability coefficients were 0.73 or greater in all but two domains. Individual domain scores as well as a weighted overall quality of life index were correlated highly with self-assessed health and the number of heart-related symptoms. CONCLUSIONS: The Multidimensional Index of Life Quality is a psychometrically reliable and valid instrument for measuring quality of life in patients with cardiovascular diseases. The MILQ also may be a suitable measure for other types of chronic diseases. 相似文献
127.
128.
NE Zakharova NP Vaneeva NE Iastrebova NG Kalina MM Tokarskaia VV Sergeev NV Tsvetkova NN Ovechko TV Sokolova 《Canadian Metallurgical Quarterly》1998,(6):82-83
A study was made into the functional status of hypophysis, adrenal cortex, ovaries, and thyroid gland in patients with kraurosis and leukoplakia vulvae. The above patients demonstrated profound disturbances in the system hypophysis-ovaries, that attest to the need for applying corrective therapies to treat the disturbed hormonal homeostasis. 相似文献
129.
Jack bean urease (EC 3.5.1.5). V. On the mechanism of action of urease on urea, formamide, acetamide, N-methylurea, and related compounds 总被引:3,自引:0,他引:3
NE Dixon PW Riddles C Gazzola RL Blakeley B Zerner 《Canadian Metallurgical Quarterly》1980,58(12):1335-1344
Acetamide and N-methylurea have been shown for the first time to be substrates for jack bean urease. In the enzymatic hydrolysis of urea, formamide, acetamide, and N-methylurea at pH 7.0 and 38 degrees C, kcat has the values 5870, 85, 0.55, and 0.075 s-1, respectively. The urease-catalyzed hydrolysis of all these substrates involves the active-site nickel ion(s). Enzymatic hydrolysis of the following compounds could not be detected: phenyl formate, p-nitroformanilide, trifluoroacetamide, p-nitrophenyl carbamate, thiourea, and O-methylisouronium ion. In the enzymatic hydrolysis of urea, the pH dependence of kcat between pH 3.4 and 7.8 indicates that at least two prototropic forms are active. Enzymatic hydrolysis of urea in the presence of methanol gave no detectable methyl carbamate. A mechanism of action for urease is proposed which involves initially an O-bonded complex between urea and an active-site Ni2+ ion and subsequently an O-bonded carbamato-enzyme intermediate. 相似文献
130.
JF Jackson RD Currier PI Terasaki NE Morton 《Canadian Metallurgical Quarterly》1977,296(20):1138-1141
To determine the possibility of genetic linkage of spinocerebellar ataxia with the histocompatibility loci, we performed HLA typing and linkage analysis on 19 members of a kindred in which spinocerebellar ataxia was segregating in an autosomal dominant inheritance pattern. The ataxia locus was located on chromosome 6 at 12-cM distance from the HLA complex with lod score of 3.15 (odds is greater than 1400:1 favoring linkage over chance findings). Thus, the presence of the ataxia gene in members of this kindred at risk can be predicted with about 90 per cent accuracy by means of HLA typing in informative matings. 相似文献