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1.
The dependence of exercise-induced hormone responses on sexual maturation was tested in a 3-year longitudinal experiment on 34 girls (aged 11–12 years at the beginning). Sexual maturation was evaluated by Tanners five-stage scale. Children cycled for 20-min at 60% maximal oxygen uptake once a year. Cortisol, insulin, growth hormone, β-oestradiol, progesterone and testosterone concentrations in venous blood were determined by radioimmunoassay procedures. Basal concentrations of growth hormone increased and of cortisol decreased when breast stage III was reached. Reaching breast stage IV was associated with an increase in basal concentrations of β-oestradiol, progesterone and testosterone. The exercise induced significant increases in concentrations of cortisol, growth hormone and β-oestradiol and a decrease in insulin concentration. At breast stage III the increase in cortisol concentration was to a lower level [467 (SEM 42) vs 567 (SEM 46)nmol · l−1] and growth hormone concentration to a higher level [29.4 (SEM 0.5) vs 12.8 (SEM 0.4)ng · ml−1], while the fall in insulin concentration was less pronounced [postexercise level 10.6 (SEM 0.9) vs 7.8 (SEM 0.8)mU · l−1] than in stage II. The magnitude of the cortisol response was reduced in the last stage of breast development (+42.1% vs +55.5% at stage II, +66.2% at stage III, and +50.0% at stage IV). The magnitude of β-oestradiol response was the lowest in breast stage IV (+15.8%) and the highest at stage V (+41.1%). The progesterone response became significant at stage IV and testosterone response at stage V. In conclusion, we found that reaching breast stage III was associated with altered responses of cortisol, insulin and growth hormone concentrations while the responses of the sex hormone concentrations became pronounced in the last stages of sexual maturation. Accepted: 17 September 1997  相似文献   

2.
Abstract

I seek to understand two dimensions in the evolution and practices of medical institutions in the USA. First, I ask, how and why do medical organizations limit, suspend, or redirect profit-oriented functions to abide by principles of altruism and still survive in a competitive market economy? Reaching out to poor and immigrant populations entails non-economic factors, including the deployment of religious and humanitarian narratives. Conversely, the extent and character of legislative actions supporting philanthropic endeavours is closely related to mobilization at the grassroots level. I investigate the ways in which community organizations bring about changes to support practices that confound, at least to some extent, market expectations and underscore the significance of political action to secure health care services on behalf of low-income populations, including immigrants.  相似文献   

3.
刘彦梅  陈飞宇 《生物磁学》2011,(19):3728-3733
目的:初步了解了进口与国产医疗设备与耗材的发展状况和使用反馈情况,并对国内医疗设备与耗材行业的发展提供合理化建议。方法:通过对苏北地区某三级甲等医院设备科工作人员、医生、护士长、患者及患者家属进行调研或访谈,并以调研和访谈的统计结果为依据得出结论并提出建议。结果:技术成熟的中小型医疗设备或耗材,从质量、价格等因素综合考虑,国内产品优于进口产品,一定程度上得到了医务人员和消费者的认可。在高端大中型医疗设备与耗材方面,进口产品具有较大的技术优势。结论:国内医疗设备生产企业应当积极开展研发工作,提高产品的技术含量与质量,巩固自身在中小型医疗设备与耗材方面的优势,并努力在高端大中型医疗设备与耗材方面取得突破。  相似文献   

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目的:初步了解了进口与国产医疗设备与耗材的发展状况和使用反馈情况,并对国内医疗设备与耗材行业的发展提供合理化建议。方法:通过对苏北地区某三级甲等医院设备科工作人员、医生、护士长、患者及患者家属进行调研或访谈,并以调研和访谈的统计结果为依据得出结论并提出建议。结果:技术成熟的中小型医疗设备或耗材,从质量、价格等因素综合考虑,国内产品优于进口产品,一定程度上得到了医务人员和消费者的认可。在高端大中型医疗设备与耗材方面,进口产品具有较大的技术优势。结论:国内医疗设备生产企业应当积极开展研发工作,提高产品的技术含量与质量,巩固自身在中小型医疗设备与耗材方面的优势,并努力在高端大中型医疗设备与耗材方面取得突破。  相似文献   

6.
The Miocene Globigerina Limestone of the Maltese islands contains widespread omission surfaces with very different characteristics and origins.The terminal Lower Globigerina Limestone hardground (TLGLHg) formed during a period of falling sea level. Coccolith assemblages suggest shallowness. Sedimentary structures and trace fossil assemblages, indicate increasing frequency of storm events and erosional episodes, towards the surface. Calcite cementation which took place around Thalassinoides burrows and formed irregular nodules was followed by dissolution of aragonite. It is suggested that lithification was linked to microbial reactions involving organic matter.In contrast two later surfaces, the terminal Middle Globigerina Limestone omissionground (TMGLOg), which marks the Lower to Middle Miocene boundary, and the Fomm-ir-Rih local hardground (FiRLHg) both contain early diagenetic dolomite. Lithification took place in two phases. The dolomite is interpreted to have formed beneath the sea floor; it was subsequently exhumed and partially corroded as the precipitation of calcitic and phosphatic cements took place around burrows open to the circulation of sea water.  相似文献   

7.
The contents of total lipids, phospholipids, cholesterol, triglyceride and free fatty acid in intima and media of thoracic and abdominal segments of aorta from normal human subjects and rhesus monkeys were determined. An increase in total lipids in intima as compared to that of media was noted in both species. A comparison of lipid contents of thoracic and abdominal segments from both species revealed that abdominal segment contained significantly greater lipid. Further, human thoracic and abdominal aortic intima and media had higher content of cholesterol as compared to that of monkey aorta. The differences in lipid profile in aorta of these two species have been highlighted to provide a clue with respect to the differences in the prevalence and morphology of atherosclerosis as seen in monkey and man.  相似文献   

8.
医德是医疗卫生领域精神文明建设的重要部分,也是调整医务人员与病人、医务人员之间以及与社会之间关系的行为准则。医德范畴是指人们对现代医务人员职业道德和医患关系的总结,它不仅概括了医生所应履行的职责义务,而且反映着一段时间内医患关系的本质。本文通过对医德范畴内,医生的权利和义务、责任和良心、功力和荣誉、审慎和保密四类问题的阐述,探讨当下医生在工作中应该保持何种心态,如何与患者进行沟通,以期更好地提供医疗服务。  相似文献   

9.
植物引种驯化研究概述   总被引:38,自引:0,他引:38  
植物引种驯化是植物学的一个分支学科,该学科与植物的迁地保护和当地的经济建设紧密相关,属于应用基础研究的范畴。但有关理论和方法的研究至今仍显得比较零碎,不够系统,判断植物引种驯化成功的标准尚不够明确。本文就植物引种驯化的概念和意义、主要理论和方法、影响其成败的因子、途径和程序、判断植物引种驯化成功的标准等进行了综述和探讨,并提出了植物引种驯化的展望。  相似文献   

10.
11.
In the chromoplast fraction and in the chromoplast-free fraction, obtained from Calendula officinalis ligulate flowers, the contents of individual free and ester-bound triterpene alcohols and sterols as well as the fatty acid components of the ester form were determined. It was shown that all sterols and triterpene monols in both forms occur in the two subtractions investigated, whereas all diols are localized only in the chromoplast fraction. The compositions of the fatty acids esterifying monols and sterols were similar to those esterifying diols in the chromoplasts. However, the fatty acids esterifying extra-chromoplast monols and sterols were different. This result indicates that triterpene monol esters are substrates for the biosynthesis of 3-monoesters of diols.  相似文献   

12.
Regulation of cellular immune responses by selenium   总被引:9,自引:0,他引:9  
Selenium (Se) is an essential nutritional factor that affects the development and expression of cell-mediated immune responses directed toward malignant cells. These studies have shown that dietary (2 ppm for 8 wk) or in in vitro (1×10−7 M) supplementation with Se (as sodium selenite) results in a significant enhancement of the proliferative responses of spleen lymphocytes from C57B1/6J mice in response to stimulation with mitogen or antigen. Se deficiency (0.02 ppm for 8 wk) had the opposite effect. The alterations in the ability of the cells to proliferate, which occurred in the absence of changes in the endogenous levels of interleukin-2 (II2) or interleukin 1, were apparently related to the ability of Se to alter the kinetics of expression of high-affinity Il2 receptors on the surface of activated lymphocytes. This resulted in an enhanced or delayed clonal expansion of the cells, and in an increased or decreased frequency of cytotoxic cells within a given cell population. The changes in tumor cytotoxicity were paralleled by changes in the amounts of lymphotoxin produced by the activated cells. Dietary Se modulations had a comparable effect on macrophage-mediated tumor cytodestruction. The results also suggested that Se exerts its effect 8–24 h after stimulation, and that it most likely affects processes in the cytoplasmic and/or nuclear compartments of activated lymphocytes.  相似文献   

13.
14.
Fetal calf serum (FCS) and PMA (phorbol 12-myristate-13-acetate) specifically stimulate the synthesis of heparan sulfate proteoglycan in endothelial cells. Staurosporine and n-butanol, kinase inhibitors, abolish the PMA effect. Forskolin and 8-bromo adenosine 3′:5′-cyclic monophosphate, activators of, respectively, adenylate cyclase and protein kinase A cannot reproduce the PMA effect. The kinetics of cell entry into S phase of the endothelial cells was determined by DNA synthesis ([3H]-thymidine and Br-dU incorporation), and flow cytometry. The mitogenic effect of fetal calf serum is abolished by PMA. Also, PMA pre-treatment inhibits the enhanced synthesis of heparan sulfate proteoglycan after a second PMA exposure. Remarkably, the stimulation of heparan sulfate proteoglycan synthesis by fetal calf serum and PMA seems to be mainly restricted to G1 phase. Therefore fetal calf serum and PMA cause an enhanced synthesis of heparan sulfate proteoglycan, and PMA causes a cell cycle block at G1 phase. J. Cell. Biochem. 70:563–572, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

15.
Azadirachta indica, also known as neem, is commonly found in many semi-tropical and tropical countries including India, Pakistan, and Bangladesh. The components extracted from neem plant have been used in traditional medicine for the cure of multiple diseases including cancer for centuries. The extracts of seeds, leaves, flowers, and fruits of neem have consistently shown chemopreventive and antitumor effects in different types of cancer. Azadirachtin and nimbolide are among the few bioactive components in neem that have been studied extensively, but research on a great number of additional bioactive components is warranted. The key anticancer effects of neem components on malignant cells include inhibition of cell proliferation, induction of cell death, suppression of cancer angiogenesis, restoration of cellular reduction/oxidation (redox) balance, and enhancement of the host immune responses against tumor cells. While the underlying mechanisms of these effects are mostly unclear, the suppression of NF-κB signaling pathway is, at least partially, involved in the anticancer functions of neem components. Importantly, the anti-proliferative and apoptosis-inducing effects of neem components are tumor selective as the effects on normal cells are significantly weaker. In addition, neem extracts sensitize cancer cells to immunotherapy and radiotherapy, and enhance the efficacy of certain cancer chemotherapeutic agents. This review summarizes the current updates on the anticancer effects of neem components and their possible impact on managing cancer incidence and treatment.  相似文献   

16.
史铀  胡兴宇 《人类学学报》1996,15(3):241-249
报告4308例幼儿至青少年期口唇部11项指标活体测量的均数及性别差异。发现少年以前口部无显著性的性差,唇高等8项指标自13岁开始,红唇高等3项开始,红唇高等3项指标在18岁后开始出现明显性差。唇高等6项指标生长发育曲线随年龄增长上升平缓,无生长发育高峰。口裂宽等5项指标的曲线则随年龄增长上升较陡,有明显的发育高峰。  相似文献   

17.
In this study, the synthetic way to new N-pyridinyl(methyl)indolylpropanamides acting as non acidic NSAIDs has been described. Pharmacomodulation was carried out at N1 and C5 of the indole ring and at the level of the propanamide chain. N3-pyridinylmethyl-[1(4-chlorobenzyl-5-chloroindol-3-yl)propanamide represents one of the most potent compounds in the TPA-induced mouse ear swelling assay, with a level of activity higher than that of ibuprofen and comparable to that of dexamethasone.  相似文献   

18.
Resident Arctic charr, Salvelinus alpinus, are widespread throughout the island of Newfoundland. This study examines aspects of the biology and spatial and temporal distributions of the charr of Gander Lake, the third largest in Newfoundland (surface area = 11320ha, maximum depth = 288m, mean depth = 105.4m). The deepest part of the lake is approximately 258m below sea level. The lake is well oxygenated from the surface to the bottom during all seasons. Sampling was conducted with Lundgren multiple-mesh experimental gillnets and baited hooks. There appears to be two morphs present, based on colour (dark and pale) and certain meristic characteristics. Dark charr were caught mainly in benthic nets (at depths from 1 to 100m inclusive) with only a few pelagic captures. Pale charr were caught only in benthic nets at depths between 20 and 100m inclusive. The maximum depth sampled was 196m, but there was no catch. There was a tendency for dark charr to be found in deeper, cooler water as the upper water column and inshore areas warmed during summer. There was no apparent trend in size of charr with depth sampled. Dark and pale charr both fed on benthic macroinvertebrates; sticklebacks were consumed only by dark charr and the importance of this prey item increased with size of predator. Zooplankton and surface food were not utilised by Gander Lake charr. Results of the study are compared with findings reported for other water bodies in Newfoundland and Labrador, North America, and Europe, particularly Loch Ness which has similarities in morphometry and trophic status to Gander Lake.  相似文献   

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20.
Little information exists on the responses of soil fungal and bacterial communities in high elevation coniferous forest/open meadow ecosystems of the northwest United States of America to treatments that impact vegetation and soil conditions. An experiment was conducted in which soil cores were reciprocally transplanted between immediately adjacent forests and meadows at two high elevation (∼1,600 m) sites (Carpenter and Lookout) in the H.J. Andrews Experimental Forest located in the Cascade Mountains of Oregon. Half of the cores were placed in PVC pipe (closed) to prevent new root colonization, whereas the other cores were placed in mesh bags (open) to allow recolonization by fine roots. A duplicate set of open and closed soil cores was not transferred between sites and was incubated in place. After 2 year, soil cores were removed and changes in fungal and bacterial biomasses determined using light microscopy, and changes in microbial community composition determined by PLFA analysis, and by length heterogeneity PCR of the internal transcribed spacer region of fungal ribosomal DNA. At both sites soil microbial community structures had responded to treatments after 2 year of incubation. At Carpenter, both fungal and bacterial community structures of forest soil changed significantly in response to transfer from forest to meadow, with the shift in fungal community structure being accompanied by a significant decrease in the PLFA biomarker of fungal biomass,18:2ω6,9. At Lookout, both fungal and bacterial community structures of forest soil changed significantly in response to open versus closed core treatments, with the shift in the fungal community being accompanied by a significant decrease in the 18:2ω6,9 content of closed cores, and the shift in the bacterial community structure being accompanied by a significant increase in bacterial biomass of closed cores. At both sites, fungal community structures of meadow soils changed differently between open and closed cores in response to transfer to forest, and were accompanied by increases in the18:2ω6,9 content of open cores. Although there were no significant treatment effects on the bacterial community structure of meadow soil at either site, bacterial biomass was significantly higher in closed versus open cores regardless of transfer.  相似文献   

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