用生物素化重组质粒探针检测产蛋下降综合症病毒核酸

用ＥＤＳ－７６标准毒株感染鸭胚后,提取病毒核酸,经ＰｓｔＩ酶切后,与质粒ｐＴ７／Ｔ３α－１９重组,并转化到大肠杆菌ＤＨ５α中,筛选出一个插入片段为３１８ｂｐ的重组质粒,并命名为ｐＴＥＺＰ３。用生物素标记该重组质粒后,分别对正常鸭胚尿囊液、各地分离的ＥＤＳ毒株和禽类易感的几种病毒进行核酸杂交试验,结果该探针对实验中收到的几种ＥＤＳ分离毒均产生阳性反应,而不与正常鸭胚尿囊液和其它几种禽类病毒交;该探针     

肾综合征出血热人体组织中病毒包涵体的性质及意义的进一步研究

应用免疫组化、原位分子杂交、电镜及免疫电镜等方法进一步对肾综合征出血热人体尸检组织中病毒包涵体（ＩＢ）的抗原、核酸性质和超微结构特点作了进一步观察。结果,在３９例中的２０例尸检病例组织中显示出病毒核蛋白抗原和血凝素抗抗原阳性的ＩＢ,其中包括１６例陕西尸检病例组织中的６例休克期和１例多尿期病例,１７例上海病例中的３例休克期和９例少尿期病例及３例江西病例中的１例休克期病例。ＩＢ主要分布在呼吸道和肺泡、肾远曲小管和集合管、胃肠道、腺垂体、扁桃体、胰腺、前列腺等组织的粘膜上皮和腺上皮细胞及肝细胞和睾丸生精上皮细胞胞浆中,阳性细胞形态基本正常。应用原位分子杂交,可在该组细胞小同时检测到病毒ＲＮＡ,多为胞浆内弥漫阳性,仅少数组织中显示出病毒ＲＮＡ阳性ＩＢ结构。电镜观察阳性组织细胞中出现由大量微丝微管及颗粒样结构组成的ＩＢ结构,其小的病毒颗粒状结构、内质网及纤维丝状结构呈病毒抗原阳性,上述结构位于高尔基体区。结果说明该病毒有感染上皮细胞的特性,对其宿主细胞的致细胞病变作用是极其温和的,且多表现在亚细胞水平。ＩＢ可能是病毒过量表达抗原的堆积或病毒复制部位,而微丝微管结构可能参与病毒的感染过程。     

Pregnancy induced hypertension: a role for peroxidation in microvillus plasma membranes

It has been recently hypothesized that in PIH a placental oxidant-antioxidant imbalance might cause the release of lipoperoxidation products into the circulation, with subsequent damage of endothelial cell membranes. In this hypothesis the endothelial cell and further increase in circulating lipoperoxide levels, which are by themselves able to induce smooth muscle constriction and increased pressor responsiveness to angiotensin II. In order to investigate this issue, we studied the basal content of lipid peroxides in terms of malondialdehyde (MDA) in the syncytiotrophoblast plasma membranes (SPM) from PIH women. Moreover, we investigated the susceptibility to peroxidation of SPM using anin vitro oxidative stress as a tool to verify the predisposition to thein vivo development of peroxidation products. The fatty acid composition of the membranes was also analyzed. Microvillus membrane lipoperoxide concentrations were significantly increased in PIH women (62.8±7.6 ng MDA/mg prot) compared with healthy pregnant subjects (37.6±4.8 ng MDA/mg prot; p<0.01).The formation of TBARS under the action of phenylhydrazine was significantly greater in PIH women (90.3±7.4 mmol MDA/mol cholesterol) than in normal pregnant subjects (68.6±6.4 mmol MDA/mol cholesterol; p<0.01). In PIH microvillus membrane we also observed a significant increase of the content of polyunsaturated arachidonic acid.The increased susceptibility to oxidative stress of SPMs from PIH women might be due either to reduced antioxidant systems or to an abnormality of the lipid composition of the membrane. The present work also demonstrated in PIH a reduction in the SPM content of saturated fatty acids with an increase in polyunsaturated fatty acids, which are the major substrate for peroxidation. On the other hand, the higher lipoperoxidation may be due to the observed increased susceptibility to peroxidative stress, to a primary reduction in placental perfusion with tissue hypoxia or to both factors, which can potentiate each other.     

Comparisons between the inorganic content of healthy and hypertensive rat tissues by inductively coupled plasma-mass spectrometry

The inorganic contents of bone, brain, erythrocyte, heart, kidney cortex, kidney medulla, liver, lung, muscle and plasma from spontaneously hypertensive rats were compared with those of the same tissues from healthy Sprague-Dawley rats. A general inductively coupled plasma-mass spectrometry method developed for multi-element determinations of most of the elements present in biological tissues was used. Variations were found not only for major elements, as expected, but also for many trace elements in several tissues.     

DOCA—Salt高血压大鼠模型的一种简易制备方法：DOCA硅胶管皮下埋入法

用外径４ｍｍ,内径２．５０ｍｍ的硅胶管制成长２５ｍｍ,管内填入ＤＯＣＡ１００ｍｇ,管壁钻有１０一１４个直径约３００μｍ微孔的药管,埋入雄性ＳＤ大鼠（１４０±９ｇ）右下腹皮下,摘除一侧肾脏,术后喂１％盐水。埋管后３周即可形成高血压,埋管后８周大鼠的收缩压达２３．３±０．３７ｋＰａ。而ＤＯＣＡ皮下注射组大鼠（１０ｍｇ／周）术后５周形成高血压,术后１３周大鼠的收缩压达２３．３±０．６６ｋＰａ。两组升压曲线回归系数（１．２９５和０．６９２）之间的差异有极显著性意义（Ｐ＜０．００１）。对照鼠的收缩压一直保持在正常水平（１６±０．１６ｋＰａ）。与ＤＯＣＡ皮下注射法相比,皮下埋管法具有两个显著优点：（１）升压速率较快,升压幅度较大;（２）方法简便可靠,重复性好。     

Prevalence of Human Herpesvirus 6 Variants A and B in Patients with Chronic Fatigue Syndrome

Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome.     

Wing dimorphism and the migratory syndrome: Correlated traits for migratory tendency in wing dimorphic insects

The hypothesis that the morphological, physiological, and behavioral traits comprising the migratory syndrome in insects are genetically correlated through pleiotropic effects of genes controlling the titre of a common hormonal determinant is explored. Evidence that juvenile hormone (JH) influences the component traits of the migratory syndrome is presented, and thus JH is assumed to be the underlying, common determinant. However, readers are cautioned that this does not imply that JH is solely responsible for these traits, nor is this necessary for the arguments presented. For wing dimorphic taxa, the “correlated traits hypothesis” predicts covariance within wing morphs between JH titre and the proportion winged. Four simple genetic models for wing-morph determination are considered: single-locus with short-winged (SW) dominant; single-locus with long-winged (LW) dominant; polygenic, fixed threshold, shifting distribution; and polygenic, shifting threshold, fixed distribution. In each case, wing morphology is assumed to be a threshold trait with the liability being JH titre at some critical stage of development. All models predict covariation between %LW and the mean JH titre of at least one of the wing morphs, but the form and direction of the relationship depends critically on the genetic model used. The results suggest that we should expect the traits associated with the migratory syndrome, and hence the trade-offs associated with the evolution of wing dimorphism, to be correlated with proportion winged and, in this sense, to be frequency-dependent.     

慢性缺氧对大鼠左右心室功能、心肌肌原纤维Ca~（2＋），Mg~（2＋）－ATP

模拟５０００ｍ中度缺氧时,大鼠右室功能显著加强,而左室功能加强不显著;左右心室肌原纤维Ｃａ２＋,Ｍｇ２＋－ＡＴＰ酶活性下降,肌球蛋白同功酶Ｖ２和Ｖ３百分含量增加,Ｖ１百分含量减少。８０００ｍ重度缺氧时,右室功能减弱,但无统计学意义,左室功能减弱有显著性;ＡＴＰ酶活性和同功酶的变化超过５０００ｍ组。此外,右室ＡＴＰ酶活性与ＰＡＰ呈反比且有显著性,左室ＡＴＰ酶活性与ＣＡＳＰ虽也呈反比但无显著性;右室同功酶Ｖ３百分含量与ＰＡＰ呈正比,左室同功酶Ｖ３百分含量与ＣＡＳＰ不呈比例。上述结果表明,因短期突发严重缺氧引起的心肌供氧不足对左心室心肌的直接损伤作用大于右心室心肌。     

Induction of apoptosis and c-myc in L1210 lymphocytic leukemia cells by adenosine

High concentrations of adenosine (Ado), when added to L1210 lymphocytic leukemia cells, resulted in apoptosis or programmed cell death. The apoptotic process was accompanied by distinct morphological changes including chromatin condensation and blebbing of plasma membranes. Extensive DNA fragmentation was correlated with Ado concentrations. Furthermore, apoptosis in these cells was preceded by an early but transient expression of c-myc proto-oncogene, and was not influenced by homocysteine thiolactone added to the cells. Since severe combined immunodeficiency (SCID) is associated with a deficiency of adenosine deaminase, leading to defects in both cellular and humoral immunity, Ado-induced apoptosis may thus be a contributing factor in the pathology of SCID.     

The evolution and ecology of multiple antipredator defences

Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such “defence portfolios” that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of specific sensory systems (e.g., visual) or specific types of defences (especially aposematism). In this review, we aim to build a comprehensive framework for conceptualizing the evolution of multiple prey defences, beginning with hypotheses for the evolution of multiple defences in general, and defence portfolios in particular. We then examine idealized models of resource trade-offs and functional interactions between traits, along with evidence supporting them. We find that defence portfolios are constrained by resource allocation to other aspects of life history, as well as functional incompatibilities between different defences. We also find that selection is likely to favour combinations of defences that have synergistic effects on predator behaviour and prey survival. Next, we examine specific aspects of prey ecology, genetics and development, and predator cognition that modify the predictions of current hypotheses or introduce competing hypotheses. We outline schema for gathering data on the distribution of prey defences across species and geography, determining how multiple defences are produced, and testing the proximate mechanisms by which multiple prey defences impact predator behaviour. Adopting these approaches will strengthen our understanding of multiple defensive strategies.