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81.
The purpose of this study was to examine the effects of long-term rugby participation on bone mineral content (BMC) and density (BMD) of male rugby players and to determine if the diverse stimuli elicited by the actions of forwards and backs affect their skeleton differently. Dual energy X-ray absorptiometry (DXA) scans were obtained from 20 male rugby players (10 Forwards and 10 Backs) who actively participated in rugby for the past 13 yr, and from 29 age matched non active subjects of the same ethnic origin. Both groups (rugby players and controls) had comparable age (23.6 +/- 3.7 yr vs. 25.6 +/- 3.4 yr), height (178.1 +/- 4.0 cm vs. 178.3 +/- 6.0 cm), and body fat percentage (14.2 +/- 4.4 vs. 16.5 +/- 5.1). Rugby players showed greater total body mass, and greater total lean and fat body masses than control subjects (p < 0.01). Whole spine BMC and BMD were 52 % and 15 % higher, respectively, in the rugby players than in the control subjects (p < 0.001). Furthermore, rugby players displayed higher skeletal BMC (40 %, 37 % and 58 % for legs, arms and pelvis, respectively) and BMD (16 %, 21 % and 17 %, respectively) than controls. Within the rugby group, forwards were taller, heavier and had greater body fat percentage, and greater total lean and fat body masses than backs (p < 0.05 to p < 0.001). Likewise, BMC, BMD and bone area for the whole body and at specific sites such as arms, spine and legs were also greater in the forwards (p < 0.05 to p < 0.001). Long-term rugby participation, starting at pubertal age, is associated with markedly increased BMC, BMD and bone size at all skeletal sites, except at the head. The musculo-skeletal adaptations, greater in forwards than in backs, could mimic training responses and therefore explain the bone features, localized in specific stressed regions.  相似文献   
82.
83.
PURPOSE: The aim of this study was to assess the outcome in patients with penile cancer. METHODS AND MATERIALS: A total of 60 patients with penile carcinoma were included. Of the patients, 45 (n = 27) underwent surgery, and 51 underwent definitive (n = 29) or postoperative (n = 22) radiotherapy (RT). Median follow-up was 62 months. RESULTS: Median time to locoregional relapse was 14 months. Local failure was observed in 3 of 23 patients (13%) treated with surgery with or without postoperative RT vs. in 19 of 33 patients (56%) given organ-sparing treatment (p = 0.0008). Of 22 local failures, 16 (73%) were salvaged with surgery. Of the 33 patients treated with definitive RT (n = 29) and the 4 patients refusing RT after excisional biopsy, local control was obtained with organ preservation in 13 (39%). In the remaining 20, 4 patients with local failure underwent salvage conservatively, resulting in an ultimate penis preservation rate of 17 of 33 (52%) patients treated with definitive RT. The 5-year and 10-year probability of surviving with an intact penis was 43% and 26%, respectively. There was no survival difference between the patients treated with definitive RT and primary surgery (56% vs. 53%; p = 0.16). In multivariate analysis, independent factors influencing survival were N-classification and pathologic grade. Surgery was the only independent predictor for better local control. CONCLUSION: Based on our study findings, in patients with penile cancer, local control is superior with surgery. However, there is no difference in survival between patients treated with surgery and those treated with definitive RT, with 52% organ preservation.  相似文献   
84.
The exploration of the deep lung remains very limited. Indeed, all the current examinations give only indirect information on this part of the lung. Thus, the new technique of double transfer of carbon monoxide (CO) and nitric oxide (NO) allows a more precise study of the pulmonary gas exchange by analyzing separately the characteristics of the membrane, by measurement of the membrane diffusion (Dm), and of the pulmonary capillary, by measurement of pulmonary capillary blood volume (Vc). With this technique, a more objective and non invasive study of the physiological changes, as age and the exercise, and pathological factors like systemic, cardio-vascular or pulmonary diseases on alveolo capillary membrane is possible.  相似文献   
85.
The cytotoxicity of 30 cyclopentanone derivatives was studied in vitro, in a clonogenic assay using murine leukemia L1210. Results are compared to those obtained with reference medicaments. 17 derivatives exhibit activities against L1210 cells.  相似文献   
86.
PURPOSE: To assess the outcome and prognostic factors in patients with orbital lymphoma treated by radiotherapy (RT). METHODS AND MATERIALS: Between 1980 and 1999, 90 consecutive patients with primary orbital lymphoma were treated in 13 member institutions of the Rare Cancer Network. A full staging workup was completed in 56 patients. Seventy-eight patients had low-, 6 intermediate-, and 6 high-grade lymphoma, and 75 had a single orbital localization. All patients underwent RT with a median dose of 34.2 Gy (range 4.0-50.4). Eleven patients received chemotherapy in addition to RT. RESULTS: After RT, local control was achieved in 97% of the patients. Local progression occurred in 2% and local relapse 1%. The rate of systemic relapse was 20%, and 9% of the patients developed metachronous contralateral eye involvement. The 5-year disease-free survival, overall survival, and cause-specific survival rate was 65%, 78%, and 87%, respectively. In univariate analyses, the statistically significant favorable prognostic factors were younger age, low grade, normal erythrocyte sedimentation rate, absence of muscular infiltration, complete response to treatment, conjunctival localization, and normal lactate dehydrogenase value for overall survival, disease-free survival, and freedom from treatment failure. In multivariate analysis, the favorable factors were younger age and low grade for overall and disease-free survival; a favorable response, conjunctival localization, and complete staging were highly significant for disease-free survival and freedom from treatment failure. Neither the RT technique nor the total dose influenced the outcome. Cataract and xerophthalmia were the most prominent late toxicities. CONCLUSION: Moderate- to low-dose RT alone is able to control primary orbital lymphoma with low morbidity. A full staging workup is warranted in these patients. Prognostic factors were identified that could be useful in the overall management of this uncommon site of primary lymphoma.  相似文献   
87.
The study was conducted to characterize the action of NaF, which had relaxing property in carbachol precontracted isolated bovine bronchus, on airway responsiveness challenged by acetylcholine receptor agonists in rats and asthmatic humans.Tracheal flow rate and airway resistance were measured in anaesthetized rats. NaF was delivered either before carbachol challenge or together with carbachol. Patients with mild asthma were challenged with methacholine aerosol, and NaF was delivered when FEV1 fell by more than 20%. The results indicated that: (1) in rats NaF significantly inhibited carbachol-induced bronchial constriction when inhaled prior to carbachol challenge as airway resistances in the NaF and NaF+verapamil groups were significantly lower than those in the control group; (2) NaF significantly reversed carbachol or methacholine-induced bronchial constriction in asthmatic patients. In conclusion, NaF, delivered in form of aerosol, reduced bronchial responsiveness to carbachol in rats and had a bronchodilating effect on rat and human airways precontracted by inhalation of acetylcholine analogs.  相似文献   
88.
Recently, this laboratory reported an autoreactivity of myoglobin (Mb)3 antisera with the Mb of the species in which the antisera are raised. Also, animals injected with autologous Mb mounted an autoimmune antibody and T-lymphocyte proliferative response against this protein. This posed the possibility that autoimmune recognition might be a general phenomenon not confined only to sequestered proteins such as Mb. Using RSA, we have demonstrated unambiguously that RSA cross-reacted with rabbit antisera to bovine (BSA) or to human (HSA) albumin. In exchange experiments, 125I-labelled RSA was bound by the IgG in the immune complexes isolated from rabbit antisera to BSA or HSA. Also, 125I-antibodies were bound by RSA-adsorbents. Both binding activities were inhibited specifically by RSA. RSA was isolated from three rabbits and each rabbit was immunized with its own RSA. In each rabbit autoantibodies were found by exchange between immune complexes and the rabbit's own [125I]-RSA. Also, 125I-antibodies from each rabbit were bound by adsorbents of the rabbit's own RSA. Inhibition studies, data on preimmune sera and on antisera against other proteins confirmed the specificity of the binding. The findings confirm the universality of autoimmune recognition and lend support to our previous suggestion that antigenic sites are ‘structurally-inherent’ in the protein.  相似文献   
89.
The present studies were carried out in order to investigate the cross-reaction of botulinum neurotoxins (BoNTs) with human and mouse antibodies against tetanus neurotoxin (TeNT) and determine whether injection of BoNT into a host that has been primed with TeNT would result in boosting of the response to the injected BoNT. Human antisera against TeNT obtained from 9 individuals were found to exhibit substantial cross-reaction with BoNTs A and B. We prepared antibodies (Abs) against inactivated tetanus neurotoxin (TeNT) in outbred mice and determined the binding of these Abs to active TeNT and active botulinum neurotoxins (BoNTs) A and B. Blood samples were collected before immunization (day 0) and on days 42, 82 and 125 after the first injection. The reactions of these sera with the immunizing antigen (inactivated TeNT), active TeNT, active BoNT/A and active BoNT/B were determined. At a fixed dilution (1:62.5 v/v), the sera contained high levels of Abs that reacted with TeNT and also with BoNTs A and B. Throughout the test period (up through day 125) and at different dilutions the cross-reactions of the antisera with BoNT/B were almost twice those with BoNT/A. The reactions of the antisera with the immunizing antigen (inactive TeNT) or with active TeNT were essentially equal throughout the dilution range tested (1:16-1:500 v/v). To determine whether injection of BoNT/A or B into a host that had been primed with TeNT resulted in boosting of the response to the priming antigen (TeNT) as well as BoNT/A or B, mice were primed with TeNT and boosted 21 days later with TeNT, BoNT/A or BoNT/B. Appropriate controls were also employed. Blood samples were collected prior to TeNT priming (day -1) and on days 21, 32, 46 and 67 after priming. In TeNT-primed mice, BoNTs A or B boosted the anti-TeNT Ab responses slightly but had no significant boosting effect on the Ab populations that bind to BoNTs A or B. It is concluded that while Abs against TeNT cross react with BoNTs and the cross reaction with BoNT/B is almost double that of BoNT/A, injection of BoNTs A or B in the presence of a prior active immunity against TeNT is not very likely to make the host mount an Ab response against the injected BoNT.  相似文献   
90.
An animal model of myasthenia gravis (MG), termed experimental autoimmune MG (EAMG), can be induced in C57BL/6 (B6, H-2b) mice by immunization with Torpedo californica acetylcholine receptor (tAChR). We have investigated the effect of vaccination with MHC class II peptide I-A beta(b)62-76 on clinical EAMG and on T cell and antibody (Ab) responses against tAChR. B6 mice were vaccinated with the peptide (25 microg/mouse) four times prior to two injections with tAChR. The incidence of clinical EAMG in vaccinated mice was 14% (3 out of 22 mice) compared to 48% (17 out of 35 mice) in control non-vaccinated or PBS-immunized mice. The T cells of the vaccinated group showed lower proliferative responses to tAChR and to T-cell epitope-containing tAChR alpha-chain peptides than the T cells of controls. In addition, the Ab responses in the vaccinated group was also lower against tAChR and some of the B-cell epitope-containing tAChR alpha-chain peptides.  相似文献   
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