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The ability of various sulfur-containing compounds to replace L-methionine (L-Met) was investigated by metabolic balance studies in man. N-acetyl-L-Methionine (AcMet), D-methionine (D-Met), and sodium sulfate (Na2SO4) were used to supplement a diet deficient in sulfur amino acids. The daily diet contained 4.5 g nitrogen (N) from isolated soybean protein (SB) and 4.5 g from glycine and alanine (9 g total N). SB diet was given alone or supplemented to six adult men for periods of 9 days after a standardization period with an equal N eggwhite diet, preceded by a 2-day zero N adaptation period. Supplements provided equivalent amounts of sulfur to that present in 420 ml L-Met, the amount added to SB to bring the total sulfur amino acid content to 900 mg/day. AcMet was as benfeficial as L-Met in improving N balance but D-Met was not as effective as L-Met. Difference between balances obtained with L-Met and Na2SO4 was not significant due to large variation in response to Na2SO4. While addition of D-Met to SB did not result in significantly greater N retention than unsupplemented SB, NA2SO4 addition did cause increased N retention. 相似文献
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An HPLC procedure for determining sorbitol in bulk sorbitol is described. An Aminex HPX-87 column (Bio-Rad) is used with water as a mobile phase and with a refractive index detector to monitor column eluate. Sorbitol is separated from pentaerythritol, erythritol, ribitol, ethylene glycol, propylene glycol, arabitol, galactitol, mannitol, iditol, and other carbohydrates. The precision of the sorbitol determination, characterized by a 95% confidence interval, corresponds to +/- 1.22%. 相似文献
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O Eton DD Kharkevitch MA Gianan MI Ross K Itoh MW Pride C Donawho AC Buzaid PF Mansfield JE Lee SS Legha C Plager NE Papadopoulos AY Bedikian RS Benjamin CM Balch 《Canadian Metallurgical Quarterly》1998,4(3):619-627
Advances in transdermal therapeutic systems (TTS) and the technology involved have been rapid because of the sophistications of physiology and biology on skin, enhancing methodology for the skin penetration of drugs, and material and polymer sciences on the pharmaceutical additives. In this review paper, such progress was introduced and the future on the TTS was augured. 相似文献
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A fetal lamb model was developed to investigate the capacity of fetal articular cartilage for repair after the creation of a superficial defect. Superficial defects, 100 micrometers deep, were made in the articular cartilage of the trochlear groove in the distal aspect of the femur in eighteen fetal lambs that were halfway through the 145-day gestational period; the contralateral limb was used as a sham control. The wounds were allowed to heal in utero for three, seven, fourteen, twenty-one, or twenty-eight days. Seven days after the injury, the defects were filled with a hypocellular matrix, which stained lightly with safranin O. At twenty-eight days, the staining of the matrix was similar to that of the sham controls and the chondrocyte density and the architectural arrangement of the cell layers had been restored. An inflammatory response was not elicited, and no fibrous scar tissue was observed. 相似文献
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OBJECTIVE: To determine the duration of time to the recurrence of pain attributable to endometriosis after the discontinuation of treatment with danazol or a GnRH agonist (GnRH-a) in patients who have had a satisfactory response to the treatment. DESIGN: Retrospective study. SETTING: Nine academic medical centers in three countries. PATIENT(S): Three hundred twenty-seven women with diagnosed and staged endometriosis who were treated with at least 6 months of danazol or a GnRH-a and who experienced significant pain relief with therapy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Duration of pain relief after completion of treatment as determined by a patient-initiated report of pain recurrence or increase in pain severity requiring intervention. RESULT(S): The median time to the recurrence of pain was 6.1 months for patients treated with danazol and 5.2 months for patients treated with a GnRH-a. CONCLUSION(S): Although there was a lack of uniformity in treatment effects across sites, the analyses have taken into account major covariant effects. The time to the recurrence of endometriosis-associated pain after danazol treatment was slightly longer than that after GnRH-a treatment. 相似文献
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A national sample of 148 directors of hospice social service departments (or persons most familiar with the delivery of social services in the hospice) participated in an exploratory study investigating the effects of the acquired immune deficiency syndrome (AIDS) epidemic on the delivery of hospice social services. Findings suggest, as does the literature, that the psychosocial needs of persons dying from AIDS present different challenges than those of traditional hospice patients. Furthermore, the results indicate the need for greater collaborative efforts among community agencies as well as specific and ongoing training for staff and volunteers who work with persons with AIDS (PWAs). Implications for the delivery of hospice social services to this population are discussed. 相似文献