子宫颈糜烂病毒病因的探讨

491份宫颈拭子病毒分离结果表明:糜烂宫颈单纯疱疹病毒(HSV)分离阳性率(30.8％)是正常宫颈(2.6％)的11.8倍,用人干扰素治疗一个疗程后,病毒分离率下降至疗前的1/4.36例糜烂宫颈活体组织DNA分子杂交表明,乳头瘤病毒16型(HPV-16)阳性者占52.8和,HPV-18占17.9％,HPV-6B占28.1％,HPV-11占7.7％,251例宫颈糜烂患者经人(?)D型基因工程干扰素双盲对比治疗后,总有效率达93.8％,显效率达60％,分析临床疗效与HSV分离率的变化表明,临床有效病例中有35％(49/140)在治疗后病毒阴转,有57％在疗前疗后均未分离出HSV,有5％在疗前疗后保持阳性不变,有2.9％疗前阴性,疗后阳性,上述结果表明,HSV和HPV与慢性宫颈炎有一定关系。     

Pollen as a chronometer and sediment tracer,Burrinjuck Reservoir,Australia

Pollen analysis is widely used to reconstruct vegetation and land use histories, but can also provide sedimentological information. At Burrinjuck Reservoir, in south-eastern Australia, annual grass pollen peaks are used to distinguish each year's sediment, even when there are no visible laminations. In conjunction with other dating methods, this allows the determination of year by year influxes of all sediment components. Pollen grains in the Burrinjuck sediments are shown to be predominantly waterborne so that they can be used to trace sediment to its source in particular vegetation stands. Pollen concentration and the proportion of damaged pollen might also distinguish sediment eroded from topsoils and that from subsoils. Pollen analysis can thus be used to locate specific erosion events in both time and space.     

Macroinvertebrate community loss as a result of headwater stream acidification in the Vosges Mountains (N-E France)

The relationships between water chemistry and aquatic macroinvertebrate communities of 41 headwater streams were studied in the Vosges Mountains (N-E of France) in an attempt to assess the impact of acidification on macroinvertebrate diversity. The taxa richness of macroinvertebrates decreased drastically in headwater streams which were characterized by low pH, low calcium and high aluminum content. All taxonomic groups were affected, but Molluscans, Crustaceans and Ephemeroptera disappeared totally from strongly acidified streams. Simple indices based on taxa richness such as the coefficient of community loss may provide accurate tools to quickly assess the impact of acidification on macroinvertebrate communities. Despite the reduction of atmospheric SO₂ emissions, acidification of freshwater in the Vosges Mountains continues to affect streams which were believed in the past to constitute refuge biotopes for numerous species. Consequently, acidification represents a real threat for numerous invertebrates. This study arises the question of the evolution in the future of headwater stream ecosystems. Urgent decisions and interventions are required to preserve non-acidified streams and to restore impacted ecosystems while awaiting spontaneous recovery.     

RPDS基牙牙周指数及牙菌斑细菌相对分布的检测分析

目的　观察基牙牙周指数及牙菌斑细菌相对分布的动态变化,以深入了解ＲＰＤｓ 对口腔微生态系影响的机理及特点。方法　在预先规定的７ 个观察期,按照文献检测基牙菌斑指数（ＰＬＩ） 、龈炎指数（ＧＩ） 及牙龈出血指数（ＧＢＩ） ;采用刚果红负性染色涂片检查法,检测基牙龈下菌斑细菌相对分布变化。结果　①患者戴用ＲＰＤｓ 后短期内基牙ＰＬＩ、ＧＩ、ＧＢＩ均明显升高（Ｐ＜ ０．０１） ,且在前６ 个月内逐渐升高,６ 个月之后则有所降低并趋于平稳;②戴用ＲＰＤｓ后牙菌斑细菌中球菌比例减小,而梭杆菌和螺旋体的比例升高。结论：戴用ＲＰＤｓ 会引起基牙ＰＬＩ、ＧＩ、ＧＢＩ升高及牙菌斑细菌中致病细菌如螺旋体、梭状杆菌比例增加。这对认识ＲＰＤｓ 对口腔微生态系影响的机制及临床防治ＲＰＤｓ 所致口腔病变具有有效的理论指导价值。     

可摘局部义齿基牙易发龋坏部位致龋菌的检出比较

通过对戴入可摘局部义齿后基牙易发龋坏部位的早期细菌组成的测定,探讨可摘局部义齿与基牙龋坏之间的潜在关系。观察１２个６活动桥的２４颗基牙,其中５、７各１２颗。病人平均年龄２５５岁。采取基牙靠缺隙侧邻面１／３区域的菌斑。采用细菌培养技术,持续观察了３个月,测定了菌斑细菌的组成。结果发现,变形链球菌的检出率在实验中呈逐渐上升趋势,且在牙位７上的检出率比在牙位５上的检出率高。结论戴用可摘局部义齿造成了口腔微生态环境的改变,促进了某些致龋细菌的生长,成为基牙发生龋坏的潜在因素     

Effects of erosion on ecto- and VA-mycorrhizal inoculum potential of soil following forest fire in southwest Oregon

The Longwood Complex wildfire in the Siskiyou Mountains of southern Oregon in August 1987 created an opportunity to study erosion and its effects on mycorrhizal fungus inoculum potential of a forest soil on steep slopes. As measured by the erosion-bridge method, most erosion occurred in a single, intense storm in December after the fire and amounted to an estimated 2 to 4 cm of surface soil. Captured eroded soil had a higher pH and P and Mg levels than residual soil. Seedlings ofLibocedrus decurrens andPseudotsuga menziesii were planted on eroded plots with additions of captured eroded soil (ET) or pasteurized eroded soil (PET) transferred to the planting holes. After one growing season,Libocedrus seedlings formed nearly 4 times the vesicular-arbuscular mycorrhizae in ET treatments and more than twice as much in PET treatments than in controls. Survival and basal area growth were significantly better in ET than in the other treatments, and both ET and PET produced more seedling shoot growth than did controls.Pseudotsuga seedlings did not differ in measured characteristics between treatments; ectomycorrhiza formation was slight, evidently the result of reduced inoculum potential resulting from the fire.     

一株广谱中和抗原性出血热病毒株的发现

一株分离自杭州市褐家鼠的出血热病毒Gou_3株的免疫血清对10株I型病毒的中和滴度除二株为160外均为320,而对4株Ⅱ型病毒的滴度为320—640,说明Gou_3株免疫血清对两型毒株中和效价大多数无差异或只差2倍,是一株中和抗原广谱的毒株。用I型和Ⅱ型毒株免疫血清对Gou_3株进行型别检定结果表明Gou_3株是Ⅱ型病毒。     

噬菌蛭弧菌简易保存方法的研究

本文报道了噬菌蛭弧菌在自来水宿主软琼脂中,于4℃环境(冰箱)存活的时间.发现噬菌蛭弧菌在自来水宿主软琼脂中,于4℃冰箱中保存,至少可以存活3个月以上,一般为5～8个月左右,最长时间可达18个月。但在自来水宿主双层琼脂平板上形成的噬斑数目,随着保存时间的延长,则有不同程度的减少。     

Human impact on an island ecosystem: pollen data from Sandoy, Faroe Islands

Aim To investigate the form and dynamics of ecosystems on an isolated island in the North Atlantic before human settlement in the first millennium ad , and the effects of human activities thereafter. Location The island of Sandoy, Faroes (61°50′ N, 6°45′ W). Methods Two sequences of lake sediments and one of peat were studied using pollen analysis and sedimentological techniques. Age models were constructed on the basis of radiocarbon dating and, in one case, tephrochronology. The data were analysed statistically and compared with existing data from the region. Results The pollen data indicate that early Holocene vegetation consisted of fell‐field communities probably growing on raw, skeletal soils. These communities gave way to grass‐ and sedge‐dominated communities, which in turn were largely replaced by dwarf shrub‐dominated blanket mire communities well before the first arrival of humans. There is evidence for episodic soil erosion, particularly in the uplands. Changes in the records attributable to human impact are minor in comparison with many other situations in the North Atlantic margins, and with certain published sequences from elsewhere in the Faroes. They include: (1) the appearance of cereal pollen and charcoal, (2) an expansion of ruderal taxa, (3) a decline in certain taxa, notably Juniperus communis and Filipendula ulmaria, and (4) a renewed increase in rates of upland soil erosion. The reliability of palaeoecological inferences drawn from these sites, and more generally from sites in similar unforested situations, is discussed. Main conclusions The subdued amplitude of palynological and sedimentological responses to settlement at these sites can be explained partly in terms of their location and partly in terms of the sensitivity of different parts of the ecosystem to human activities. This study is important in establishing that the imposition of people on the pristine environment of Sandoy, while far from negligible, especially in the immediate vicinity of early farms and at high altitudes, had relatively little ecological impact in many parts of the landscape.