Exercise-induced hormone responses in girls at different stages of sexual maturation

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     

Photoprotection of phytochrome

High-fluence-rate white light is shown to retard the degradation of phytochrome in etiolated seedlings of four different species: Amaranthus caudatus, Phaseolus radiatus (mung bean), Pisum sativum (garden pea), and Avena sativa (oat). In Amaranthus, a high photon fluence rate (approx. 1000 mol · m^-2 · s^-1) preserved nearly 50% of the total phytochrome over a period of 5 h; at 3 mol · m^-2 · s^-1, less than 8% remained over the same period. Kinetics of the loss of total phytochrome could be interpreted in terms of two populations, one with rapid, and one with slow, turnover rates. A log-linear relationship between fluence rate and proportion of slowly degrading phytochrome was observed; a similar relationship between fluence rate and the amount of phytochrome remaining after a 5-h light treatment was seen. In mung bean, although two populations of differing degradation rates were not resolvable, a similar log-linear relationship between fluence rate and amount remaining after a standard light treatment was evident. Detailed kinetic analyses were not performed with peas and oats, but comparisons of low and high fluence rates demonstrated that photoprotection was similarly effective in these species. In Amaranthus, transfer from high to low fluence rate was accompanied by a rapid increase in degradation rate, indicating that the retarding effect of high-fluence-rate light is not a consequence of the disablement of the degradative machinery.Immunochemical analyses confirmed the existence of photoprotection in all four species, and allowed the extension of the observations to periods of light treatment during which substantial chlorophyll production occurred. Considerable photoprotection was observed in oat seedlings exposed to summer sunlight. These results are interpreted in terms of the accumulation under high fluence rates of photoconversion intermediates not available to the degradative machinery which is specific for the far-red-absorbing form of phytochrome.Abbreviations Pfr far-red absorbing form of phytochrome - Po amount of phytochrome measured at time zero - Pt amount of phytochrome measured at time t - Ptot total phytochrome - WL white light     

论＂医德＂的基本范畴

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。     

Regulation of cellular immune responses by selenium

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.     

Responses of soil bacterial and fungal communities to reciprocal transfers of soil between adjacent coniferous forest and meadow vegetation in the Cascade Mountains of Oregon

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.     

食用菌产业发展需要科学研究的强力支撑

我国是世界食用菌产业大国,产量占全球总产80%,拥有全球最多的食用菌基础科学和应用技术研究者,近年来在这两个领域都取得了显著成绩,但仍远远不能满足产业发展的科学需求。我国食用菌产业的发展需要科学研究的强力支持。本专刊集结了食用菌的资源与利用、遗传育种、组学分析、生理栽培、加工技术、活性成分、保健功效评价等方面的论文共计32篇。本刊论文还涉及了食用菌与病原菌的互作研究、野生菌的种类产地鉴定等方面的研究。     

Comparative study of major lipid constituents in human and monkey aorta

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.     

关于苏北地区某三甲医院进口与国产医疗设备和耗材使用情况及反馈的研究．

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。     

Electroporative deformation of salt filled lipid vesicles

Membrane electroporation, vesicle shape deformation and aggregation of small, NaCl-filled lipid vesicles (of radius a = 50 nm) in DC electric fields was characterized using conductometric and turbidimetrical data. At pulse durations t_E≤ 55 ± 5 ms the increase in the conductivity of the vesicle suspension is due to the field-induced efflux of electrolyte through membrane electropores. Membrane electroporation and Maxwell stress on the vesicle membrane lead to vesicle elongation concomitant with small volume reduction (up to 0.6% in an electric field of E = 1 MV m^–1). At t_E > 55 ± 5 ms, further increases in the conductivity and the optical density suggest electroaggregation and electrofusion of vesicles. The conductivity changes after the electric pulse termination reflect salt ion efflux through slowly resealing electropores. The analysis of the volume reduction kinetics yields the bending rigidity κ = (4.1 ± 0.3) ⋅ 10^–20 J of the vesicle membrane. If the flow of Na⁺ and Cl^– ions from the vesicle interior is treated in terms of Hagen-Poiseuille's equation, the number of permeable electropores is N = 39 per vesicle with mean pore radius r_p = 0.85 ± 0.05 nm at E = 1 MVm^–1 and t_E≤ 55 ± 5 ms. The turbidimetric and conductometric data suggest that small lipid vesicles (a ≤ 50 nm) are not associated with extensive membrane thermal undulations or superstructures. In particular with respect to membrane curvature, the vesicle results are suggestive for the design and optimization of electroporative delivery of drugs and genes to cell tissue at small field strengths (≤1 MVm^–1) and large pulse durations (≤100 ms). Received: 8 July 1997 / Accepted: 15 September 1997     

Classification of types of ontogenetic reproduction

The object of this paper is to present an original classification of ontogenetic reproduction. The main general criterion used is the degree and type of phylogenetic differentiation. In relation to this criterion, criteria are given for the classification of the fundamental types of ontogenetic reproduction and for the classification of the types of ontogenetic generation cycles. Between the fundamental types of ontogenetic reproduction and the types of ontogenetic generation cycles there is a hierarchical relationship which shows that the former are components of the latter. Between the well-defined types of ontogenetic reproduction there exist many intermediate types.     

Effects of Simulated Acid Rain on Anatomy of Primary Leaves of Phaseolus Vulgaris

Ten-days-old bean plants (Phaseolus vulgaris L., cv. Cheren Starozagorski) were treated with simulated acid rain (pH 2.4, 2.2, 2.0 and 1.8). Anatomical changes in the primary leaves were studied 3, 48 and 168 h after a single treatment. This treatment induced: 1) change in the shape of palisade cells, contraction of their contact surfaces and expansion of spongy cells (pH 1.8, 3 h after treatment); 2) reduction of symplast connections among palisade cells and of apoplast in the spongy mesophyll (pH 1.8, 48 h after treatment); 3) destruction of adaxial epidermis and portions of palisade mesophyll, plasmolysis of spongy cells (pH 1.8, 168 h after treatment); 4) full destruction of mesophyll (pH 2.4, 2.2, 2.0 and 1.8, 168 h after treatment). The structure of abaxial epidermis was more stable than that of the adaxial one. With respect to anatomical parameters the studied species could be considered as comparatively resistant to acid rain.     

脱氮除硫菌株的分离鉴定和功能确认

从长期稳定运行的脱氮除硫反应器污泥中,分离获得两株具有脱氮除硫功能的芽孢杆菌。经形态观察、生理试验和16SrDNA序列比对,将两菌株归入芽孢杆菌属,菌株CB归类于Bacillus pseudofirmus,菌株CS则与Bacillus hemicellulosilytus和Bacillus halodurans最为接近。以Biolog板检测,菌株CB的基质多样性不明显,菌株CS则可利用Biolog板中多种碳源。菌株CB和菌株CS都能以硝酸盐氧化硫化物,其中菌株CB对硝酸盐、硫化物的转化能力大于CS,菌株CB对硝酸盐的亲和力也大于菌株CS。     

The Biology of Arctic Charr, Salvelinus Alpinus, of Gander Lake, A Large, Deep, Oligotrophic Lake in Newfoundland, Canada

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.     

Effects of potassium on the anion and cation contents of primary cultures of mouse astrocytes and neurons

Inastrocytes, as [K⁺]_o was increased from 1.2 to 10 mM, [K⁺]_i and [Cl^–]_i were increased, whereas [Na⁺]_i was decreased. As [K⁺]_o was increased from 10 to 60 mM, intracellular concentration of these three ions showed no significant change. When [K⁺]_o was increased from 60 to 122 mM, an increase in [K⁺]_i and [Cl^–]_i and a decrease in [Na⁺]_i were observed.Inneurons, as [K⁺]_o was increased from 1.2 to 2.8 mM, [Na⁺]_i and [Cl^–]_i were decreased, whereas [K⁺]_i was increased. As [K⁺]_o was increased from 2.8 to 30 mM, [K⁺]_i, [Na⁺]_i and [Cl^–]_i showed no significant change. When [K⁺]_o was increased from 30 to 122 mM, [K⁺]_i and [Cl^–]_i were increased, whereas [Na⁺]_i was decreased. Inastrocytes, pH_i increased when [K⁺]_o was increased. Inneurons, there was a biphasic change in pH_i. In lower [K⁺]_o (1.2–2.8 mM) pH_i decreased as [K⁺]_o increased, whereas in higher [K⁺]_o (2.8–122 mM) pH_i was directly related to [K⁺]_o. In bothastrocytes andneurons, changes in [K⁺]_o did not affect the extracellular water content, whereas the intracellular water content increased as the [K⁺]_o increased. Transmembrane potential (E_m) as measured with Tl-204 was inversely related to [K⁺]_o between 1.2 and 90 mM, a ten-fold increase in [K⁺]_o depolarized the astrocytes by about 56 mV and the neurons about 52 mV. The E_m values measured with Tl-204 were close to the potassium equilibrium potential (E_k) except those in neurons at lower [K⁺]_o. However, they were not equal to the chloride equilibrium potential (E_Cl) at [K⁺]_o lower than 30 mM in both astrocytes and neurons. Results of this study demonstrate that alteration of [K⁺]_o produced different changes in [K⁺]_i, [Na⁺]_i, [Cl^–]_i, and pH_i in astrocytes and neurons. The data show that astrocytes can adapt to alterations in [K⁺]_o, in such a way to maintain a more suitable environment for neurons.     

Hiatal surfaces from the Miocene Globigerina Limestone Formation of Malta: Biostratigraphy, sedimentology, trace fossils and early diagenesis

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.     

重庆市近郊大气无机氮、硫沉降特征及其来源分析

以重庆市近郊中梁山槽谷为研究区,利用气象站和沉降仪获取2017年5月-2018年4月的大气无机氮、硫沉降数据和降水δ¹⁵N-NO₃^-、δ¹⁸O-NO₃^-和δ³⁴S-SO₄^2-、δ¹⁸O-SO₄^2-数据,通过离子浓度比值、同位素值和气团后向轨迹探讨了研究区大气中氮、硫沉降变化特征及其来源。结果表明：（1）大气DIN总沉降量为19.99 kg/hm²,干、湿沉降量分别占11%和89%;大气S总沉降量为32.62 kg/hm²,干、湿沉降量分别占13%和87%。大气氮、硫湿沉降量与降水量均呈正相关（n=12,P < 0.01）,氮、硫干湿沉降量具有明显的季节差异。（2）降水NH₄⁺-N/NO₃^--N比值介于0.45-2.2之间,雨季（5-10月）NH₄⁺-N/NO₃^--N>1,旱季（11-次年4月）NH₄⁺-N/NO₃^--N<1,表明雨季氮主要来源于农业源,旱季来源于工业和交通源;降水NO₃^-/SO₄^2-比值介于0.1-1.25之间,平均值为0.63,表明硫来源以固定污染源（燃煤）为主。（3）大气降水δ¹⁵N-NO₃^-、δ¹⁸O-NO₃^-值分别为-3.8‰-3.9‰（平均值为0.4‰±2.6‰）和58.7‰-98.7‰（平均值为76.1‰±14.3‰）,夏季偏负,冬季偏正;降水δ³⁴S-SO₄^2-和δ¹⁸O-SO₄^2-变化范围分别为1.3‰-3.2‰（平均值为2.3‰±1‰）和5.3‰-8.5‰（平均值为7.1‰±1.6‰）,大气降水中NO₃^-和SO₄^2-主要来源于当地的化石燃料燃烧,同时受到周边污染物的远距离传输影响。（4）气团后向轨迹表明影响研究区氮、硫干湿沉降来源的主要因素是东亚季风,北东-南西走向的川东平行岭谷大地貌格局加剧了季风的影响。     

关于苏北地区某三甲医院进口与国产医疗设备和耗材使用情况

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。