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91.
92.
The structural and thermotropic properties of alpha-hydroxy fatty acid (HFA) and non-hydroxy fatty acid (NFA) ceramides (CER) have been studied using differential scanning calorimetry (DSC) and X-ray diffraction techniques. The DSC of anhydrous HFA-CER shows a single, sharp reversible transition at 95.6 degrees C (delta H = 15.3 kcal/mol). At intermediate hydrations HFA-CER exhibited more complex behavior but at maximum hydration only a single reversible transition is observed at 80.0 degrees C (delta H = 8.5 kcal/mol). X-ray diffraction of hydrated (74% water) HFA-CER at 20 degrees C shows a lamellar structure with a bilayer periodicity d = 60.7 Angstrum; a single wide angle reflection at 4.2 Angstrum is characteristic of hexagonal chain packing. Above the main transition temperature at 91 degrees C, a hexagonal (HII) phase is observed. In contrast, DSC of anhydrous NFA-CER demonstrates two thermal transitions at 81.3 degrees C (delta H = 6.8 kcal/mol) and 85.9 degrees C (delta H = 3.5 kcal/mol). With increasing hydration, both transitions shift towards lower temperatures; at maximum hydration, on heating, the endothermic transitions occur at 72.7 degrees C (delta H = 9.8 kcal/mol) and 81.1 degrees C (delta H = 4.0 kcal/mol). On cooling, there is hysteresis of both transitions. X-ray diffraction of NFA-CER (80% water) at 20 degrees C shows a well-ordered lamellar structure with a bilayer periodicity d = 58.6 Angstrum and three wide-angle reflections at 4.6 Angstrum, 4.2 Angstrum, and 3.8 Angstrum. At 77 degrees C (between the two transitions), again a lamellar structure exists with reduced bilayer periodicity d = 53.1 Angstrum and four wide-angle reflections at 4.6 Angstrum, 4.2 Angstrum, and 3.8 Angstrum are observed. Above the second transition, only a single low angle reflection at 30.0 Angstrum is observed; a diffuse reflection at 4.6 Angstrum is indicative of a melted chain phase. Thus, HFA-CER exhibits a simple phase behavior involving the reversible conversion of a gel phase to a hexagonal phase (L beta-->HII). However, NFA-CER shows a more complex polymorphic phase behavior involving two gel phases. 相似文献
93.
94.
RC Smith JS Lyles JA Mettler AA Marshall LF Van Egeren BE Stoffelmayr GG Osborn V Shebroe 《Canadian Metallurgical Quarterly》1995,70(8):729-732
PURPOSE: To use a controlled, randomized design to assess the effect on patient satisfaction of an intensive psychosocial training program for residents. METHOD: Twenty-six first-year residents, in two internal medicine and family practice community-based programs affiliated with the Michigan State University College of Human Medicine, were randomly assigned during 1991 and 1992 to a control group or a one-month intensive training program. Experiential teaching focused on many psychosocial skills required in primary care. A 29-item questionnaire administered before and after the residents' training evaluated their patients' satisfaction regarding patient disclosure, physician empathy, confidence in physician, general satisfaction, and comparison of the physician with other physicians. Analyses of covariance with groups and gender as factors and pre-training patient satisfaction scores as the covariate evaluated the effect of the training. RESULTS: The patients of the trained residents expressed more confidence in their physicians (p = .01) and more general satisfaction (p = .02) than did the patients of controls. The effect of training on patient satisfaction with patient disclosure (p < .01) and physician empathy (p < .05) was greater for female than for male residents. CONCLUSION: The intensive psychosocial training program for residents improved their patients' satisfaction. 相似文献
95.
LTH on Yakhta-4M unit was used in benign prostatic hyperplasia (BPH). The prostate was heated transrectally by directional radiation. The course of treatment comprised 5 sessions for 60 min twice a week. The efficacy of the treatment was assessed 3 years later in 78 patients which were divided into 4 groups: 31 patients with BPH, 30 patients with BPH in combination with chronic prostatitis, 9 patients with acute urine retention and 8 patients with cystostomy fistula. 5 patients underwent surgery. LTH is safe in relation to side effects, may be used both at early stage of the disease and in risk of operative intervention. 相似文献
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A Ravasio M Pasquinelli B Currò Dossi W Neri C Guidi M Gessaroli F Rasi R Fabbri G Mazzini GG Rebucci 《Canadian Metallurgical Quarterly》1995,16(7):487-492
We report the effects of treatment with plasma-exchange (PE) and intravenous immune globulins (IVIg) in 36 out of 50 patients with Guillain-Barré syndrome (GBS) recruited by an incidence study in the Emilia-Romagna region of Italy. Comparison of the patients treated with PE and IVIg showed no significant differences in terms of effectiveness in improving the clinical course of GBS: at one month, respectively 11.1% and 25% had recovered, and 55.5% and 58.3% had improved by at least one grade. These results are in agreement with those of the Dutch GBS trial. No relapses were observed in either group. Moreover, our results showed no difference in clinical outcome at 1 and 3 months between the patients receiving only one therapy and those receiving two; a second cycle of therapy did not seem to improve the clinical course of the disease significantly. We conclude that PE and IVIg are both safe and effective therapies for GBS. 相似文献
98.
99.
LK Malendowicz C Macchi GG Nussdorfer A Markowska 《Canadian Metallurgical Quarterly》1996,11(3):641-645
The effects of a prolonged administration of bradykinin (BK) and/or D-Arg, [Hyp3, D-Phe7]-BK, a specific antagonist of BK receptors (BK-A) (daily subcutaneous injections of 4 nmol/rat for 6 days) on the function of the pituitary-adrenocortical axis were investigated. BK did not change plasma aldosterone concentration (PAC), but markedly lowered that of corticosterone (PBC) and consequently induced a compensatory hypersecretion of ACTH by the pituitary gland. BK-A did not apparently affect the function and growth of the adrenal gland, but, when administered together with BK, markedly raised both PAC and PBC, and provoked a significant atrophy of the adrenal gland, probably due to loss of parenchymal cells. Taken together, these rather puzzling findings do not appear to provide clear evidence for the involvement of BK in the physiological regulation of adrenocortical growth and steroidogenic capacity in rats. 相似文献
100.
The case of an occult abscess associated with an autologous nasal hump cartilage chin graft is presented. The graft was placed 30 years prior to secondary aesthetic surgery performed on December 22, 1992. In the course of the removal of the autologous tissue, an abscess pocket was discovered which subsequently cultured positive for Staphylococcus epidermidis. The area was thoroughly debrided and irrigated, and a preoperatively custom-fabricated silicone elastomer implant was placed. A 2-week course of appropriate antibiotic therapy was administered following receipt of the culture and sensitivity data. The patient suffered no postoperative complications. The bacteriology of implant colonization and infection in the light of host defenses would predict such a course, although, if known preoperatively, the more prudent course of abstinence from alloplastic implantation would likely be dictated in the aesthetic surgery patient. 相似文献