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1.
A duct system was arranged through which flowed air of controlled ion concentration. In series was a chamber with a flexible dielectric floor which made possible electrical detection of activity.Exposure to various ion concentrations of either polarity produced pronounced effects.In addition to gross motor activity six other behavioural parameters were recorded. The lowest ion concentration were most effective. In addition to presenting a controlled ambient ion concertration the ion current drawn by the animal was measured. This varied markedly from rat to rat.
This work was supported by Public Health Service Research Grant #AP00305-02 from the Division of Air Pollution, Bureau of State Services and also by a grant from the Atmospheric Science Research Center of the State University of New York. 相似文献
Zusammenfassung Ein Kanalsystem zum Durchfluss von Luft bekannter Ionenkonzentration wurde eingerichtet. Angeschlossen war eine Kammer mit einem beweglichen dielektrischen Boden, der die Registrierung der Aktivität von Ratten ermöglichte. Neben der motorischen Aktivität wurden 6 andere Verhaltensformen der Tiere registriert.Die niedrigste Ionenkonzentration war am wirksamsten zur Anregung der Aktivität. Neben der Ionenkonzentration in der Kammer wurde der von den Tieren eingeatmete Ionenstrom gemessen; er variierte stark von Tier zu Tier.
Resume On a construit un canal dans lequel il est possible de faire circuler de l'air dont la concentration en ions est contrôlable. On y a adjoint une cellule dont le sol est constitué par un diélectrique flexible permettant de déceler électriquement l'activité de petits animaux.En exposant des rats à des concentrations ioniques variables et de polarité différente, on peut constater des effets prononcés sur le comportement des animaux. En effet, en plus de l'activité motrice, on a enregistré six autres formes de ce comportement. Ce sont les plus faibles concentrations qui produisent le plus d'effets. A part la concentration en ions à l'intérieur de la cellule, on a également mesuré la quantité d'ions absorbés par les bêtes par voie respiratoire. Cette quantité varie fortement d'un individu à l'autre.
This work was supported by Public Health Service Research Grant #AP00305-02 from the Division of Air Pollution, Bureau of State Services and also by a grant from the Atmospheric Science Research Center of the State University of New York. 相似文献
2.
对我国52种微茎类吸虫的18项成虫形态学特征进行主成分分析,结果表明:卵巢位置、子宫延伸位置等7项性状对第一主成分贡献较大,提示描述器官位置的指标是重要的分类依据。52个虫种在前三个主成分上的排序图显示应将其划分成4个亚科。 相似文献
3.
本文就萤叶甲亚科中柱萤叶甲属鞘翅具黑色刻点的种类进行研究,共记述4种,我国已记录3种,其中1种为新种。 相似文献
4.
5.
Chathurika Henpita Rajesh Vyas Chastity L. Healy Tra L. Kieu Aditi U. Gurkar Matthew J. Yousefzadeh Yuxiang Cui Aiping Lu Luise A. Angelini Ryan D. O'Kelly Sara J. McGowan Sanjay Chandrasekhar Rebecca R. Vanderpool Danielle Hennessy-Wack Mark A. Ross Timothy N. Bachman Charles McTiernan Smitha P. S. Pillai Warren Ladiges Mitra Lavasani Johnny Huard Donna Beer-Stolz Claudette M. St. Croix Simon C. Watkins Paul D. Robbins Ana L. Mora Eric E. Kelley Yinsheng Wang Timothy D. O'Connell Laura J. Niedernhofer 《Aging cell》2023,22(4):e13782
Cardiomyopathy is a progressive disease of the myocardium leading to impaired contractility. Genotoxic cancer therapies are known to be potent drivers of cardiomyopathy, whereas causes of spontaneous disease remain unclear. To test the hypothesis that endogenous genotoxic stress contributes to cardiomyopathy, we deleted the DNA repair gene Ercc1 specifically in striated muscle using a floxed allele of Ercc1 and mice expressing Cre under control of the muscle-specific creatinine kinase (Ckmm) promoter or depleted systemically (Ercc1−/D mice). Ckmm-Cre+/−;Ercc1−/fl mice expired suddenly of heart disease by 7 months of age. As young adults, the hearts of Ckmm-Cre+/−;Ercc1−/fl mice were structurally and functionally normal, but by 6-months-of-age, there was significant ventricular dilation, wall thinning, interstitial fibrosis, and systolic dysfunction indicative of dilated cardiomyopathy. Cardiac tissue from the tissue-specific or systemic model showed increased apoptosis and cardiac myocytes from Ckmm-Cre+/-;Ercc1−/fl mice were hypersensitive to genotoxins, resulting in apoptosis. p53 levels and target gene expression, including several antioxidants, were increased in cardiac tissue from Ckmm-Cre+/−;Ercc1−/fl and Ercc1−/D mice. Despite this, cardiac tissue from older mutant mice showed evidence of increased oxidative stress. Genetic or pharmacologic inhibition of p53 attenuated apoptosis and improved disease markers. Similarly, overexpression of mitochondrial-targeted catalase improved disease markers. Together, these data support the conclusion that DNA damage produced endogenously can drive cardiac disease and does so mechanistically via chronic activation of p53 and increased oxidative stress, driving cardiac myocyte apoptosis, dilated cardiomyopathy, and sudden death. 相似文献
6.
本文报道在湛江市附近海域海鸟体内获得的两种吸虫,经鉴定为新种,命名为巨口类茎吸虫,新种Microphalloides macrostonrs sp.nov.,珊瑚多黄吸虫,新种Multivitellus coralius sp.nov. 相似文献
7.
Summary A girl with partial trisomy for the short arm of chromosome 10(p12pter) due to mal chromosome segregation in the father 46,XY,t(7;10)(p22;p12) is described. The major abnormalities in this case are: mottled skin, mid-facial hypoplasia, low percentiles for weight, length, and head circumference, and club feet.To whom offprint requests should be sent 相似文献
8.
David S. Bachman Paul D. MacLean Annton M. Allen 《Primates; journal of primatology》1977,18(2):465-469
This report describes a case of premature ventricular contractions and electrocardiographic signs of myocardial infarction
which developed following stimulation of the left vagus nerve in an awake squirrel monkey. Post mortem examination revealed
myocardial myocytolysis. 相似文献
9.
以化学纯饲料饲养北京的桃蚜 总被引:4,自引:0,他引:4
应用修改后的Dadd和Mitter(1966)全纯饲料配方配制成人工饲料饲养定居在北京温室烟草上的桃蚜 Myzus persicae可完成生活史井连续饲养3代。本文描述饲料配制、饲养和取食量测定的方法。这3代初羽化无翅孤雌胎生雌蚜的平均体重分别为:440±90.7μg,264±104.9μg和312±127.9μg。用放射性同位素稀释法测定取食量的结果得悉若虫期的总取食量每蚜约为1.74μg,相当于1.16μl。 相似文献
10.
The action of prostaglandins and indomethacin on gastric mucosal cyclic nucleotide concentrations was evaluated in 18 anesthetized mongrel dogs. Prostaglandins E1 (PGE1) and E2 (PGE2) (25 microgram/kg bolus, then 2 micrograms/kg/min) were administered both intravenously (4 experiments; femoral vein) and directly into the gastric mucosal circulation (10 experiments; superior mesenteric artery). The possible synergistic effect of pre-treatment and continuous arterial infusion of indomethacin (5 mg/kg bolus for 5 min, then 5 mg/min), a prostaglandin synthetase inhibitor, with PGE2 was studied in 4 experiments. Antral and fundic mucosa were biopsied and measured by radioimmunoassay for cyclic nucleotides. Doses of PGE1 and PGE2 which inhibited histamine-stimulated canine gastric acid secretion did not significantly alter antral or fundic mucosal cyclic nucleotide concentrations. Concomitant infusion of PGE2 with indomethacin did not potentiate the mucosal nucleotide response compared to PGE2 alone. These studies fail to implicate cyclic nucleotides as mediators of the inhibitory acid response response induced by PGE1 or PGE2 in intact dog stomach. 相似文献