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31.
Current immunosuppressive regimens for clinical transplantation are immunologically non-specific, are associated with acute and chronic toxic side-effects [1] and are unable to prevent chronic graft loss in a significant proportion of patients. Additionally, new and increasingly powerful drugs are being introduced to induce non-specific immunosuppression, and therefore this is likely to be followed by an increase in related complications such as the induction of cancers. Hence, there is a need for an alternative approach. It has been shown that long-term survival of murine cardiac grafts can be induced by the monoclonal antibody YIS 191 that depletes CD4 +T cells in vivo [2]. In this study, we have investigated the ability of a non-depleting antibody to produce better graft survival.  相似文献   
32.
A 59-year-old male presented with systemic mastocytosis with extensive skeletal involvement resulting in vertebral compression fractures and bone pain. Histomorphometric analysis of bone revealed increased mast cells, elevated static parameters of bone resorption, and low bone formation. Serum calcium, phosphorus, and alkaline phosphatase were normal; however, serum 1,25-dihydroxyvitamin D3 and osteocalcin levels were low. Histamine levels in plasma and urine were elevated. Following therapy with ketotifen, the patient had resolution of bone pain along with decreased flushing and pruritus. Elevated plasma and urine histamine levels normalized, as did 1,25-dihydroxyvitamin D3 and osteocalcin levels. Indices of low bone formation improved on therapy. Eroded surfaces improved but remained elevated. This case is the first demonstration that bone symptoms and histomorphometric change in systemic mastocytosis are reversed with inhibition of mast cell degranulation. The role of mast cells and their products in bone metabolism is poorly understood, but the therapy of bone disease in systemic mastocytosis should include inhibition of the release of mast cell products along with the use of histamine antagonist.  相似文献   
33.
This clinical-arthrographic investigation compares power spectral analysis of temporomandibular joint sounds with different arthrographic characteristics of intracapsular dysfunction. The quantitative comparison of specific parameters of the sound power-spectrum waveform may provide a sensitive and accurate noninvasive tool for diagnosis and treatment.  相似文献   
34.
G M Lawrie  G C Morris  D H Glaeser 《JAMA》1986,256(21):2967-2971
To determine the long-term influence of the severity of preoperative diabetes mellitus on the results of coronary bypass, a review was made of 212 diabetics operated on between 1968 and 1973, of whom 87 patients (41%) were receiving no drugs, 108 patients (50.9%) were receiving oral hypoglycemic agents, and 17 patients (8%) were receiving insulin. They were compared with 1,222 nondiabetic patients operated on over the same period. Perioperative mortality was similar in the diabetics and nondiabetics: 7.1% vs 4.5%. Improvement in anginal symptoms was similar in all patient groups: 85.9% to 92.7%. Overall 15-year survival probability was .53 for the nondiabetic group, .43 for the diabetics not receiving drugs, .33 for those receiving oral agents, and .19 for the insulin-treated patients. Late graft patency ranged from 78% to 90% and was comparable in all groups. The preoperative blood glucose level was an important predictor of late mortality in all diabetic patients. Thus, coronary bypass surgery was effective in all groups of diabetic patients in long-term relief of anginal symptoms. Intermediate-term survival rates were good in all groups, but the initial severity of the diabetes was an important determinant of long-term survival rates.  相似文献   
35.
The objective of this study was to determine the effects of flavonoids on the in vitro monocarboxylate transporter 1 (MCT1)-mediated transport and in vivo disposition of the drug of abuse, gamma-hydroxybutyrate (GHB). The uptake of GHB in rat MCT1 gene-transfected MDA-MB231 cells was significantly decreased in the presence of the flavonoids apigenin, biochanin A, chrysin, diosemin, fisetin, genistein, hesperitin, kaempferol, luteolin, morin, narigenin, phloretin, and quercetin, but was not affected by the flavonoid glycosides phloridzin and rutin. The IC(50) values for luteolin, morin, and phloretin were 0.41 +/- 0.14, 6.41 +/- 2.01, and 2.57 +/- 0.48 microM, with the inhibition mechanism for luteolin being competitive. [(3)H]Kaempferol and [(3)H]biochanin A did not exhibit MCT1-mediated uptake, suggesting that these flavonoids are not substrates for MCT1. The combination of luteolin and phloretin inhibited the uptake of GHB in a synergistic manner; however, the combination of luteolin and morin was antagonistic. GHB 1000 mg/kg was administered to rats by i.v. bolus, with or without the concomitant administration of luteolin 10 mg/kg i.v. After luteolin treatment, the renal and total clearances of GHB were significantly increased, probably because of inhibition of the MCT1-mediated renal reabsorption of GHB, and the sleep time significantly decreased (121 +/- 5 min versus 165 +/- 10 min) compared with control rats. Overall, the results of this study indicate that flavonoids from food or herbal products may significantly alter the pharmacokinetics and pharmacodynamics of MCT substrates.  相似文献   
36.
37.
Autologous bone marrow transplantation (BMT) is a therapeutic option for the treatment of lymphohematopoietic malignancies and solid tumors. Despite the intensive cytoreductive therapy, however, the rates of tumor recurrence after autologous BMT remain unacceptably high. Current studies suggest that the administration of cyclosporine (CsA) disrupts the reconstitution of self-tolerance following autologous BMT leading to the induction of an autoimmune graft-versus-host disease (GVHD). Studies in a rat tumor model and preliminary clinical trials suggest that this autoimmune or autologous GVHD provides a significant antitumor effect. Moreover, the antitumor effect of autologous GVHD can be enhanced by administration of gamma-interferon, which upregulates the antigen recognized by the autoreactive effector cells of autologous GVHD. These studies indicate that the induction of an autoimmune GVHD after autologous BMT may be a promising immunotherapeutic approach for treatment of certain neoplastic diseases.  相似文献   
38.
Brain tumors are increasingly prevalent. Recent advances focus attention on individual, disseminated tumor cells that cannot be imaged or eliminated. Cells of the immune system may be ideally suited to attack individual tumor cells, but more basic understanding is needed. We describe a rat model, using the lacZ reporter gene, that allows identification of individual tumor cells, and tumor-leukocyte interactions in vivo. The model demonstrates how widely tumor can disseminate, without secondary tumorigenesis or recruitment of nonneoplastic cells. It demonstrates that leukocytes have access to disseminating tumor. Among its many applications, this work lays a foundation for developing cell-mediated immunotherapy against individual brain tumor cells.  相似文献   
39.
Metabolic inactivation of bleomycin (BLM) by cysteine proteinase-like enzymes is thought to be a major mechanism of BLM tumor resistance. We now report that the human colon carcinoma COLO-205 is highly resistant to BLM and that E-64, a cysteine proteinase inhibitor, sensitizes COLO-205 to BLM. Treatment of COLO-205-bearing nude mice with either E-64 (40 mg/kg) or BLM (10 mg/kg) alone did not inhibit COLO-205 growth. However, pretreatment with E-64 prior to BLM prevented these xenografts from growing. Analysis by high performance liquid chromatography of in vivo BLM metabolism following [3H]BLM A2 treatment of COLO-205-bearing nude mice showed a different metabolic profile among the various organs and the tumor. Whereas [3H]BLM A2 was the only major radioactive peak detected in sera and tumors, several metabolites, including deamido-BLM A2, were found in kidney, liver, and lung as early as 15 min. Pretreatment of mice with E-64 inhibited tumor, kidney, and lung BLM A2 metabolism. Furthermore, pretreatment with E-64 increased BLM A2 accumulation in tumors (6.1-fold), kidney (4.0-fold), lung (2.8-fold), liver (1.8-fold), and serum (1.7-fold). E-64 pretreatment did not enhance the major toxicity of BLM, pulmonary fibrosis, as determined by both lung hydroxyproline levels and histopathology. Thus, the cysteine proteinase inhibitor E-64 affects the metabolic fate and the levels of accumulation of BLM in vivo. These results demonstrate that resistance of human COLO-205 tumors to BLM can be circumvented by E-64 without enhancement of the major side effect of BLM, suggesting a possible clinical use of this combination therapy.  相似文献   
40.
Reduction mammaplasty is rationed in NHS plastic surgery provision, despite abundant evidence that most women who undergo this operation obtain significant improvement in their physical health and quality of life. We suspected that women seeking reduction mammaplasty often wear ill-fitting bras, which may exacerbate some of their symptoms. Therefore, we studied 103 women who attended a nurse-run pre-assessment clinic, asking them what size bra they currently wore and then measuring them to see whether their bra size was correct. We also questioned bra manufacturers, designers and shop bra fitters about bra manufacture, sizing and fitting techniques, and we reviewed these findings. Of the 102 women suitable for inclusion in the study, all wore the wrong size bra. Their mean 'claimed' back measurement was 36 inches (range: 30-42 in.) and their mean cup size was F (range: C-J). We found that all but one underestimated their back measurement (by a mean of 4 in.; range: -2-10 in.) and overestimated their cup size (by a mean of three sizes; range: one size smaller to seven sizes larger) when compared with manufacturers' fitting guidelines. Multiple regression analysis used to assess the relationships of various factors to incorrect bra sizing showed a strong link (Pearson correlation=0.54; P<0.001) between obesity and inaccurate back measurement. The reasons why women with breast hypertrophy wear incorrectly fitting bras are discussed. We conclude that obesity, breast hypertrophy, fashion and bra-fitting practices combine to make those women who most need supportive bras the least likely to get accurately fitted bras, so exacerbating the symptoms for which they seek surgery.  相似文献   
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