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41.
The organization of the neonatal rat's brainstem trigeminal complex and its role in the formation of central trigeminal patterns 总被引:4,自引:0,他引:4
The present study delimits the relationship of primary trigeminal afferents to their targets, the brainstem trigeminal nuclei of the neonatal rat. Previously, the brainstem trigeminal complex of the rat has been subdivided on the basis of either cytoarchitectonics or patterns of succinic dehydrogenase activity into the principal sensory nucleus and the three subnuclei of the spinal trigeminal nucleus, oralis, interpolaris, and caudalis. In this paper, we demonstrate that each of these subdivisions can also be identified by its pattern of primary trigeminal afferents. In addition, we demonstrate that the terminations of these afferents are distributed in a punctate fashion which correlates with vibrissae-related patterns of histochemical staining. Further, vibrissae removal in the neonatal rat at any age studied results in a corresponding deafferentation of both the principal sensory nucleus and all subnuclei of the spinal trigeminal nucleus. This same procedure has a graded, age-dependent effect on the vibrissae-related pattern of cytochrome oxidase staining in somatosensory cortex. On this basis, we conclude that vibrissae-related pattern formation in the central trigeminal system can be best understood in terms of a single "sensitive" period for the entire system. We hypothesize that this is the period during which an interaction normally occurs between primary trigeminal afferents and target neurons of the principal sensory nucleus. 相似文献
42.
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
43.
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
44.
PSYCHOLOGICAL factors have a role in Irritable Bowel Syndrome symptomatology. The locus of control test determines an individual’s degree of internality or externality. The degree of internality or externality does not influence the site of major Irritable Bowel Syndrome symptomatology. Externalizers have a worse prognosis than internalizers. This effect on prognosis should be borne in mind when testing for diet and or drug efficacy. 相似文献
45.
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
46.
47.
Tumour necrosis factor beta (lymphotoxin) inhibits locomotion and stimulates the respiratory burst and degranulation of neutrophils. 总被引:9,自引:0,他引:9
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The data presented here demonstrate that recombinant human tumour necrosis factor beta (rHuTNF beta; lymphotoxin) is a neutrophil modulator. The lymphokine inhibited the locomotion of neutrophils and augmented the neutrophil oxygen-dependent respiratory burst in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) and phorbol myristate acetate (PMA), as measured by their capacity to produce chemiluminescence, H2O2 and superoxide. The effects on the respiratory burst occurred at a tenth of the concentration of TNF beta required to inhibit locomotion. After incubation with TNF beta, the neutrophils could be washed without any reduction in their capacity to show augmented responses. The TNF beta enhanced granule enzyme (lysozyme and beta-glucuronidase) release of neutrophils stimulated with cytochalasin B-FMLP. 相似文献
48.
A new long shelf life formulation of modified Ham's F-10 medium: Biochemical and clinical evaluation 总被引:1,自引:0,他引:1
Paul S. Weathersbee Mary M. Francis Thelma M. Macaso Mark V. Sauer Richard J. Paulson 《Journal of assisted reproduction and genetics》1995,12(3):175-179
Purpose To evaluate biochemically and clinically a new formulation of modified Ham's F-10 medium made without the inclusion of hypoxanthine. The medium was formulated for long-term storage and use by separately preparing a stable liquid (basal) portion and a freeze-dried supplement containing the labile medium components.Results Following 18 months of storage the basal medium was biochemically analyzed for its amino acid (aa's) and vitamin content. Cysteine and tryptophan were decreased to less than 30% of their starting theoretical concentrations (STCs). Asparagine, serine, tyrosine, histidine and lysine were present at 50% to 70% of their STC. The remaining aa's were all within 90% of their STCs except arginine which was at 77%. All of the vitamins were present at 90% or more of their STCs except inositol, riboflavin and'thiamine which were present at 70% of their STCs. IVF with the new formulation resulted in 13 deliveries from 51 aspirations (25%) as compared with 10/39 (26%) in 1991, when standard medium preparation was used. Oocyte donation resulted in 30 deliveries from 84 cycles (36%) with the new formulation as compared with 21/65 (32%) in 1991.Conclusions (1) The new basal with lyophilized supplement formulation produces similar clinical results in the IVF laboratory as medium prepared in the standard fashion, (2) certain amino acids and vitamins are not stable in the liquid basal medium, and (3) the separate formulation of a liquid basal medium with lyophilized supplement is convenient, viable alternative to modified Ham's F-10 medium prepared in the standard manner (i.e., from powder) and may decrease the need for frequent medium preparation.Modified Ham's F-10 Medium, Irvine Scientific, Santa Ana, California.Presented at the 42nd Annual Meeting of the Pacific Coast Fertility Society, Indian Wells, California, April 20–24, 1994. 相似文献
49.
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
50.