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排序方式: 共有2511条查询结果,搜索用时 15 毫秒
31.
SP Mahadik S Mukherjee DF Horrobin K Jenkins EE Correnti RE Scheffer 《Canadian Metallurgical Quarterly》1996,63(2-3):133-142
Recent studies have found lower red cell plasma membrane contents and composition of the long chain polyunsaturated essential fatty acid derivatives, particularly arachidonic acid and docosahexaenoic acid, in a subgroup of chronic schizophrenic patients. These fatty acids are particularly enriched in the brain. Red blood cell levels of fatty acids are influenced by diet, medications, and other factors. Cell plasma membrane compositions of arachidonic and docosahexaenoic acids were therefore examined in cultured skin fibroblasts from 12 schizophrenic patients, 8 of whom were drug-naive and in a first episode of psychosis, 6 bipolar patients, and 8 normal control subjects. Docosahexaenoic acid as well as total n-3 essential fatty acid contents were significantly lower in cell lines from schizophrenic patients than in cell lines from bipolar patients and normal subjects, with no difference between the latter two groups. Arachidonic acid levels did not differ across the groups. The essential fatty acid profile observed is consistent with deficient delta-4 desaturase activity in schizophrenic patients. 相似文献
32.
Twenty mothers of preterm babies who had survived to 1 year old, were matched for age and parity of the mother and time of birth of the baby, with 20 mothers delivering fullterm. Bone mineral, body composition and anthropometric measurements were obtained for each mother and analysed using paired t-tests. The only significant difference (P < 0.01) between the groups was a lower fat-free mass in the preterm mothers calculated from skinfold thickness measurements. 相似文献
33.
34.
SJ Ander LM Blomkvist JC M?lne KJ Johansson SP Smeds 《Canadian Metallurgical Quarterly》1997,20(11):640-647
The morphology, cell proliferation and function of transplanted normal, hyperplastic and adenomatous human parathyroid tissue was studied after transplantation to athymic mice. The iPTH was evaluated in relation to morphology. Human parathyroid tissue collected during surgery for hyperparathyroidism was implanted subcutaneously into athymic mice (nu/nu-BALB/cA) and was analysed 1, 4, 7 and 12 weeks after transplantation. The transplants were examined by light and electron microscopy and by autoradiography after continuous infusion of 3H-thymidine. The relative amount of viable tissue was evaluated using a computer image analysing programme. Graft function was evaluated by measuring human iPTH in mouse serum. A transplant take ratio of 93% was observed. The proliferation rate in adenoma grafts at 12 weeks after transplantation was five and fifteen times that observed in normal and hyperplastic transplants, respectively. In normal and adenoma groups, a continuous increase in iPTH concentrations was observed, but in the hyperplastic group the iPTH remained on the same level. The secretion of iPTH in relation to the amount of transplanted tissue and the fraction of viable tissue was at the same level at 12 weeks in normal and adenomatous grafted animals. In conclusion, human parathyroid tissue was successfully transplanted and maintained its original structure. The growth potential, but not the iPTH secretion, was significantly higher in adenoma grafts compared to grafts from hyperplastic and normal glands. 相似文献
35.
Spontaneous regression of AK-5, a histiocytic tumor, is mediated by CD3-, CD8+ NK cells through ADCC. The onset of AK-5 regression is associated with the induction of humoral immune response and the augmentation of effector function. The mechanism of tumor cell death involves both necrosis and apoptosis. Interleukin-12, a 75-kDa heterodimeric cytokine, has multiple effects on T and NK cells. We have investigated the role of IL-12 in the NK cell-mediated AK-5 tumor regression process. Subcutaneous transplantation of AK-5 tumor induced the expression of IL-12 (p35 and p40) message by Day 6-8 in the splenocytes of syngenic rats. Similarly, analysis of serum samples from tumor-bearing animals showed the presence of circulating IL-12 around the same time. Interaction of immune cells with antibody-tagged AK-5 cells in vitro also triggered the expression of IL-12 message and protein by 3 hr. The circulating IL-12 in the sera of tumor-rejecting animals, as well as rIL-12, stimulated NK cell proliferation, expression of CD16 and CD25, and the activation of NK cells function. These observations suggest that the ability of the AK-5 tumor to induce the endogenous production of IL-12 may be responsible for keeping the NK cells constantly in an activated state, thus demonstrating an efficient mechanism for the complete regression of the tumor. 相似文献
36.
M Patel RF Kaltenbach DA Nugiel RJ McHugh PK Jadhav LT Bacheler BC Cordova RM Klabe S Erickson-Viitanen S Garber C Reid SP Seitz 《Canadian Metallurgical Quarterly》1998,8(9):1077-1082
Cyclic urea SD146, a potent HIV protease inhibitor bearing a flat resistance profile, possessed poor solubility and bioavailability, which precluded further development of the compound. In an effort to improve upon the pharmacokinetic profile of the compound, several analogs modified at the P1/P1' residues were prepared and evaluated. Several of those compounds displayed significant improvement of physical properties. 相似文献
37.
38.
It seems obvious in retrospect that the treatment of disorders by interocclusal devices followed two paths: stabilization splints and functional orthopedic appliances. The dividing line between them is not always clear. Both have some function related to the position of the mandible. They may not differ significantly in their control of occlusal stability (e.g., telescoping devices anchored to stabilization splints). The stabilization splint, as well as other conservative measures, will play an increasing role in accepted therapy for TMD. The use of anterior repositioning devices for TMD, including MPD syndrome, will decrease. Research may provide answers that allow them to be used more specifically and predictably. Perhaps there will be but little change in their use where there is an association of TMD and Class II malocclusion. There will be an increase in the use of interocclusal devices for the treatment of snoring and obstructive apnea. Some additional directions seem to have emerged in the late 1980s and early 1990s: In the absence of pain and significant debilitation, treatment for TMD, if any, is to be reversible. Prevention or aggravation of TMD should be practiced to the extent possible during dental procedures. One long-term, well-designed, prospective study indicated that the incidence and severity of TMD could be reduced by appropriate occlusal adjustment. There is a small, but nevertheless important minority of patients with TMD who progress to persistent pain and/or dysfunction. Initial management of the vast majority of patents with TMD should be use of noninvasive reversible therapies. Surgery is indicated in only a relatively small percentage of cases of TMD. Research on interocclusal devices should not terminate simply because they are in part dental devices (i.e., biomechanical forms of treatment). The diagnosis and treatment of TMD has been called a dilemma, especially for those patients with chronic pain for whom no treatment has been effective. However, it would be ill-advised to abandon what treatment is already known to be effective by allowing those few but psychosocially important patients with chronic pain to determine what should be done for the vast majority of patients with TMD: reversible forms of treatment, including physiotherapy, pharmacologicals, and the stabilization occlusal bite plane splint. 相似文献
39.
SP Kraft 《Canadian Metallurgical Quarterly》1998,33(4):237-239
PURPOSE: The authors describe the first case of delayed antimetabolite-related corneal epithelial toxicity after trabeculectomy and its successful treatment with limbal stem cell transplantation. METHODS: A 73-year-old woman underwent trabeculectomy with intraoperative mitomycin C. After surgery she received six 5-mg injections of subconjunctival 5-fluorouracil (5-FU) adjacent to the bleb. RESULTS: The patient had a functioning trabeculectomy and clear cornea until 30 months after surgery, at which time she developed a nonhealing superior corneal epithelial defect. After 4 months of conservative medical management, an autologous limbal stem cell transplantation was performed. The epithelial defect resolved completely within 1 week of limbal stem cell transplantation. CONCLUSIONS: Delayed corneal epithelial toxicity may be a late complication of antimetabolite-augmented trabeculectomy. 相似文献
40.
PURPOSE: To determine the apical versus basolateral polarity of the putative anion exchanger in cultured bovine corneal endothelial cells (BCECs) and to examine the influence of Cl--dependent membrane potential (Em) changes on HCO3- transport. METHODS: BCECs grown on permeable supports were used for independent perfusion of apical and basolateral surfaces. Intracellular pH (pHi) was measured using the fluorescent dye BCECF. Relative changes in Em were measured using the fluorescent dye bis-oxonol. Western blot analysis was used to detect immunoreactivity against the anion exchanger (AE1 or AE2). RESULTS: Cl- removal from apical and basolateral surfaces produced cellular alkalinization (apical side, 0.07 pH units; basolateral side, 0.06 pH units; both sides, 0.20 pH units). Application of 100 microM H2-4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid (DIDS), an anion exchange inhibitor, on the apical side produced an alkalinization (0.02 pH units) followed by acidification (-0.05 pH units), whereas basolateral H2DIDS caused a substantial acidification (-0.16 pH units). In the absence of Na+, Cl- removal from the apical side caused a transient alkalinization (0.03 pH units) followed by a return to baseline; Cl- removal from the basolateral side caused a small (-0.03) acidification. In Na+-free Ringer, apical H2DIDS produced a transient alkalinization (0.02 pH units), whereas basolateral exposure had no effect. 5-Nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), N-phenylanthranilic acid (DPC), and niflumic acid (50-200 microM), known Cl- channel blockers, produced cellular acidification in control Ringer. Niflumic acid hyperpolarized Em and inhibited depolarization after Cl- removal. Western blot analysis failed to detect AE2 expression in cultured BCECs. However, fresh BCECs produced a trace response. CONCLUSIONS: Physiological activity of an apical anion exchanger is weak in cultured BCECs. Cultured BCECs have significant Cl- conductance. Thus, cellular alkalinization after Cl- removal is caused primarily by depolarization of Em, which drives HCO3- influx through the basolateral electrogenic Na+:nHCO3- cotransporter. In contrast with cultured BCECs, AE2 may be present in fresh cells. 相似文献