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951.
952.
RW Gruessner DE Sutherland MB Drangstveit L Wrenshall A Humar AC Gruessner 《Canadian Metallurgical Quarterly》1998,66(3):318-323
We report the use of a bone graft harvested from the palmar and ulnar aspect of the distal radius and vascularized by the palmar carpal artery for the treatment of scaphoid nonunion in 17 patients, ten of whom had already had unsuccessful surgery. Union was obtained in all cases at an average of 60 days (range, 45-90 days). The average follow-up was 16 months (range, 12-36 months). There were no failures. 相似文献
953.
954.
BACKGROUND: The aim of the study was to assess whether the appropriate pressure profile is generated by thigh-length graduated compression stockings in human subjects. The effect of leg posture on the pressure profile was assessed in three commonly used brands of graduated compression stockings. METHODS: The study involved 17 human volunteers from the Department of Orthopaedic Surgery. Three different brands of stockings commonly recommended for the prevention of deep vein thrombosis were applied to each individual and the interface pressure profile under the stocking was measured. The effect of posture was assessed by comparing the interface pressure profile with the subject supine and in standing and sitting positions. RESULTS: Appropriate median pressure profiles were achieved only with the subject standing or supine. In the sitting position with the knee flexed, a high median interface pressure in excess of 28 mmHg was generated at the popliteal fossa. Overall, inconsistent performance was found in all three brands of stockings; fewer than 30 per cent of the pressure readings fell within 20 per cent of the 'ideal'. Reversed pressure profile was observed in over 70 per cent of subjects. CONCLUSION: Thigh-length graduated compression stockings may be most effective in bedridden patients. Knee-length stockings may be more suitable for the prevention of deep vein thrombosis in ambulant patients. 相似文献
955.
956.
Hypochlorous (HOCl) and hypobromous (HOBr) acids are strong oxidants derived from myeloperoxidase and eosinophil peroxidase, the major antimicrobial enzymes of neutrophils and eosinophils, respectively. These oxidants are highly reactive with a wide range of biomolecules. At physiological pH, both HOCl and HOBr react readily with amines to form haloamines and with the unsaturated bonds of fatty acids to form halohydrins. We have investigated which of these reactions occur with phosphatidylethanolamine (PE), the predominant phospholipid of Escherichia coli. The formation of haloamines was determined by TLC and colorimetrically and the formation of halohydrins was determined by TLC and GC-MS. With HOCl, chloramines were much the preferred product and chlorohydrins were formed in substantial amounts only when HOCl was in excess of the amount required to convert the amine to the dichloramine. With HOBr at all concentrations, bromamines and bromohydrins were formed concurrently, indicating a greater relative reactivity with unsaturated fatty acids than with HOCl. The bromamine derivatives of PE, and other primary amines, were found to be more reactive than the equivalent chloramines, and were able to brominate the unsaturated bonds of fatty acids. Bromohydrins (formed directly or through the action of bromamines) may, therefore, be suitable biomarkers for the production of HOBr in vivo. 相似文献
957.
OBJECTIVE: To identify short-term drug abuse treatment location risk factors for ten large, self-insured firms starting January 1, 1989 and ending December 31, 1991. DATA SOURCES/STUDY SETTING: Study population selected from a large database of health insurance claims for all treatment events starting January 1, 1989 and ending December 31, 1991. STUDY DESIGN: A nested binomial logit method is used to estimate firm-specific patterns of treatment location. The differences in treatment location patterns among firms are then decomposed into firm effects (holding explanatory variables constant among firms) and variable effects (holding firm-specific parameters constant). PRINCIPAL FINDINGS: Probability of inpatient drug treatment is directly related to the type of drug diagnosis. The most important factors are diagnoses of drug dependence (versus drug abuse) and/or a cocaine dependence. Firm-specific factors also make a substantive difference. Controlling for patient risk factors, firm-specific probabilities of inpatient treatment vary by as much as 87 percent. Controlling for practices of firms and their insurance carriers, differing patient risk profiles cause probabilities of inpatient treatment to vary by as much as 69 percent among firms. Use of the outpatient setting increased over the three-year period. CONCLUSIONS: There are two plausible explanations for the findings. First, people beginning treatment later in the three-year period had less severe conditions than earlier cases and therefore had less need of inpatient treatment. Second, drug abuse treatment experienced the same trend toward the increased use of outpatient care that characterized treatment for other illnesses in the 1980s and early 1990s. 相似文献
958.
E Rego AC Bento RA Lopes-Martins E Antunes JC Novello S Marangoni JR Giglio B Oliveira G De Nucci 《Canadian Metallurgical Quarterly》1996,34(10):1141-1147
The venom of the Brazilian spider Phoneutria nigriventer was fractionated using a C18 microBondapack reverse-phase high-performance liquid chromatography column. The resulting fractions were assayed in the rabbit perfused corpus cavernosum tissue to identify those fractions responsible for the corpus cavernosum relaxation. Two fractions (A and B) with retention times of 18.1 and 36.7 min, respectively, induced relaxation of corpus cavernosum strips. Fraction A was selected for further biochemical characterization. Repurification of this fraction revealed the presence of a polypeptide (named PNV4) which migrates in sodium dodecyl sulphate-polyacrylamide gel electrophoresis as a single band consistent with a mol. wt close to 16,600. The amino acid composition of PNV4 showed the presence of 147 residues, a high content of Cys and a calculated mol. wt of 17,213 + Trp. The N-terminal amino acid sequence of PNV4 determined for its first 48 residues was AELTSCFPVGHECDGDASNCNCCGDDVYCGCGWGRWNCKCKVADQSYA. 相似文献
959.
AC Wiesfeld CD De Langen HJ Crijns KJ Bel HL Hillege H Wesseling KI Lie 《Canadian Metallurgical Quarterly》1996,27(4):594-600
The electrophysiologic effects of intravenously administered almokalant, a new class III antiarrhythmic drug, in 7 isoflurane-anesthetized pigs after low and high dose were investigated. Low-dose almokalant included bolus infusion of 0.05 mumol/kg/min for 5 min followed by a continuous infusion of 0.0025 mumol/kg/min for 40 min. Thereafter, a high dose of 0.2 mumol/kg/min for 5 min and 0.01 mumol/kg/min for 40 min was given. PR, QRS, AH, and HV intervals did not change during almokalant administration. The QT interval increased dose dependently from 337 +/- 17 to 442 +/- 20 ms at high dose (p < 0.05). Atrial refractory periods (AERP) were prolonged dose dependently at a 500-ms pacing cycle length from 178 +/- 15 at baseline to 227 +/- 27 and 253 +/- 23 ms during low- and high-dose almokalant infusion, respectively. For pacing cycle lengths of 400 and 300 ms, these values were 180 +/- 11, 207 +/- 25, and 259 +/- 34 and 157 +/- 12, 193 +/- 21, and 234 +/- 28 ms, respectively. At a pacing cycle length of 500 ms, mean ventricular effective refractory period (VERP) was 270 +/- 25 ms as compared with 306 +/- 24 and 337 +/- 17 during low and high dose, respectively. A similar pattern of VERP changes during both low- and high-dose infusion was noted at the shorter pacing cycle lengths, with an increase from 240 +/- 23 to 274 +/- 22 and 279 +/- 24 ms during a 400-ms cycle length and from 210 +/- 17 to 235 +/- 19 and 234 +/- 21 ms during a 300-ms cycle length. The ratio of the VERP and ventricular monophasic action potential duration (VAPD) did not change significantly. The Wenckebach cycle length increased by 36 +/- 36 and 83 +/- 37 ms with low- and high-dose almokalant infusion, respectively. The percent increase of AERP at pacing cycle lengths of 500, 400, and 300 ms during high-dose almokalant was 42, 44, and 49%, respectively; these increases for VERP were 25, 16, and 11%, respectively. In conclusion, prolongation of refractoriness by almokalant was more pronounced at the atrial than the ventricular level. Prolongation of refractoriness was maintained at short pacing cycle lengths especially in the atrium, indicating absence of reverse-use dependence of almokalant in the porcine heart. The marked atrial effects, paralleled by atrioventricular conduction slowing, and the absence of reverse use-dependence all contribute to the feasibility of use of almokalant, in particular in the treatment of supraventricular tachyarrhythmias. 相似文献
960.