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41.
A comparison between free-weight and isokinetic bench pressing 总被引:1,自引:0,他引:1
J E Lander B T Bates J A Sawhill J Hamill 《Medicine and science in sports and exercise》1985,17(3):344-353
The purpose of the study was to evaluate selected parameters describing performance characteristics of a free-weight and isokinetic bench press. A secondary purpose was an attempt to clarify the technique requirements essential for a successful lift. Parameters describing the free-weight condition were generated from cinematographic data (150 fps) for five trials each at 90 and 75% of the subject's maximal performance (1RM). Isokinetic data were obtained from an instrumented Cybex Power Bench Press at two speeds corresponding to the average speeds for the free-weight conditions. Despite differences, accommodation appeared to occur for both methods when the lifts were performed maximally. A "sticking region" was defined as the portion of the free-weight activity when the subjects' force application was less than the weight of the bar. No significant difference (P less than 0.05) was observed between the 90% 1RM (26.02%) and 75% 1RM (26.94%) mean relative time values for these regions. For the Cybex device, the percentage of the activity which was isokinetic was longer for the slower speeds of rotation (0.47 rad X s-1 = 70%) and steadily decreased until the movement was only 50% isokinetic at 1.74 rad X s-1. The observed relationships between applied force-time data along with anatomical considerations suggest an ideal technique for the lift. 相似文献
42.
Marc E. Lippman Robert B. Dickson Susan Bates Cornelius Knabbe Karen Huff Sandra Swain Mary McManaway Diane Bronzert Attan Kasid Edward P. Gelmann 《Breast cancer research and treatment》1986,7(2):59-70
Summary We consider the hypothesis that estrogen control of hormone dependent breast cancer is mediated by autocrine and paracrine growth factors secreted by the breast cancer cells themselves. Though we show direct, unmediated effects of estrogen on specific cell functions, we also provide evidence that human breast cancer cells secrete a collection of growth factors (IGF-I, TGF, TGF, a PDGF-like competency factor, and at least one new epithelial colony stimulating factor). Some of these are estrogen-regulated in hormone dependent cells, and are constitutively increased in cells which acquire independence either spontaneously or byras transfection. Collectively, the secreted growth factors are capable of promoting tumor formation by MCF-7 cells in nude mice, though not to the same extent as estrogens. There would seem to be potential for clinical intervention in the autocrine and paracrine control of breast cancer cells, including some cells which are no longer dependent on estrogens. 相似文献
43.
Breeze Penny Gray Laura A. Thomas Chloe Bates Sarah E. Brennan Alan 《Quality of life research》2022,31(11):3283-3292
Quality of Life Research - To estimate the association between changes in BMI and changes in Health-Related Quality of Life (EQ-5D-3L). The WRAP trial was a multicentre, randomised controlled trial... 相似文献
44.
45.
L Ozzello CM De Rosa EW Blank K Cantell RL Ceriani DV Habif Sr 《Breast cancer research and treatment》1993,25(3):265-276
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy. 相似文献
46.
To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs 相似文献
47.
Bates CJ Prentice A Cole TJ van der Pols JC Doyle W Finch S Smithers G Clarke PC 《The British journal of nutrition》1999,82(1):7-15
The aims of the National Diet and Nutrition Survey series are summarized, and the new National Diet and Nutrition Survey of people aged 65 years and over is explored, with particular emphasis on micronutrient intakes and status indices. Mean nutrient intakes were generally satisfactory for most micronutrients, but intakes of vitamin D, Mg, K and Cu were low. Intakes of vitamin D were far below the reference nutrient intake for people aged 65 years and over, and there was also biochemical evidence of vitamin D deficiency, for 8% of free-living and 37% of institution participants, attributed partly to limited exposure to sunlight. A substantial proportion of people living in institutions had inadequate biochemical status indices, notably for vitamin C, Fe and folate. Relationships between intake and status were close for vitamins. Mineral intakes did not correlate well with currently used status indices. Some intakes and indices, especially those of vitamin C, carotenoids, Na and K, were strongly correlated with socio-economic status and with north-south gradients in Britain. Future research challenges should address the functional and health significance of low intakes and sub-optimal biochemical indices for certain micronutrients, especially for people living in institutions; the shortcomings of mineral status indices especially as indicators of mineral intake; the social and geographical inequalities of micronutrient intakes and status, and why micronutrient status deteriorates with increasing age. The answers to these questions will help to define the characteristics of nutritional risk for older people in Britain, and to clarify future needs for education and intervention. 相似文献
48.
Retrobulbar haemorrhage (RBH) occurs in a variety of situations. It can complicate facial fractures, orbital surgery and retrobulbar injections and can occur spontaneously. It is relatively uncommon and sight-threatening RBH is even less common. If not detected early enough it can lead to devastating loss of vision. We have collected five cases of acute RBH, following trauma, associated with a profound reduction in vision. In each case a permanent loss of vision was avoided using a lateral canthotomy and inferior cantholysis approach to obtain urgent orbital decompression. 相似文献
49.
Clinical-neuroimaging analysis of 12 thrombotic thrombocytopenic purpura (TTP) patients revealed a variety of brain lesions. These included reversible cerebral edema lesions with MRI features of reversible posterior leukoencephalopathy syndrome (RPLS). Most of the RPLS patients had hypertension and renal dysfunction, suggesting RPLS due to hypertensive encephalopathy. Prompt treatment usually led to neurologic recovery and disappearance of edematous lesions. Those with infarcts or hematomas had a poorer outcome. TTP should be added to the expanding spectrum of RPLS and hypertensive encephalopathy. 相似文献
50.
Kosinski CM Cha JH Young AB Mangiarini L Bates G Schiefer J Schwarz M 《Neuroreport》1999,10(18):3891-3896
R6/2 transgenic mice express exon 1 of an abnormal human Huntington's disease (HD) gene and develop a neurological phenotype similar to HD. These mice develop ubiquitinated neuronal intranuclear inclusions (NII) which might play a central role in the pathophysiology of HD. We studied the distribution of NII in subpopulations of striatal neurons in 12-week-old R6/2 transgenic mice using fluorescent double label immunohistochemistry. We observed that most of the Calbindin-D28K positive projection neurons (89%) and the Parvalbumin positive interneurons (86%) showed ubiquitinated NII. In interneurons, however, which contain either choline acetyltransferase, neuronal nitric oxide synthase, or Calretinin, the frequency of NII was much lower (22%, 8%, 9%, respectively). Our data suggest that subpopulations of striatal neurons differ remarkably in their capability of forming ubiquitinated NII. Interneurons which are known to resist neurodegeneration in HD show less NII. 相似文献