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21.
Adult Trogoderma glabrum females assume stationary postures characterized by abdominal elevation and partial exposure of the ovipositor segments. The postural activity was studied in relation to sex pheromone production and was designated calling, or sex pheromone-releasing behaviour because it was accompanied by an increase in the rate of release of sex pheromone(s). Calling was largely restricted to an 8 hr interval centered toward the middle of a 16 hr photophase. Mating frequency and female pheromone content increased during the same interval. Because females extracted during the calling period yielded at least 10 times more pheromone than extracts prepared at other times, and because pheromone activity released during one calling period was estimated to be at least 10-fold higher than that which could be extracted from whole females several hours prior to the start of calling, heightened production of active pheromone(s) was postulated to occur during calling. Functional significance of the calling posture is discussed in relation to sex pheromone gland location. 相似文献
22.
Models of learning based on the plastic properties of the "placing reaction" in cats] 总被引:1,自引:0,他引:1
B I Kotliar V I Ma?orov E I Savchenko 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1975,25(5):967-973
A possibility of functional reorganization of initial sensorimotor connections of the forepaw has been shown on seven cats. The main initial relationships between the afferent tactile input and motor output for the ulnar joint of the cat forepaw are as follows: tactile stimulation of the dorsal surface of the paw produces a flexion in the ulnar joint ("placing reaction"), and that of the ventral surface, an extension of the paw in the ulnar joint ("magnetic reflex"); simultaneous tactile stimulation of the ventral surface of the paw blocks the "placing reaction" evoked by a touch of the dorsal side. Extinction was produced of the above unconditioned connections and elaboration of a new "cross" connection consisting in that tactile stimulation of the ventral side of the paw resulted in flexion in the ulnar joint. 相似文献
23.
Shuai Ma Shuhui Sun Jiaming Li Yanling Fan Jing Qu Liang Sun Si Wang Yiyuan Zhang Shanshan Yang Zunpeng Liu Zeming Wu Sheng Zhang Qiaoran Wang Aihua Zheng Shuguang Duo Yang Yu Juan Carlos Izpisua Belmonte Piu Chan Qi Zhou Moshi Song Weiqi Zhang Guang-Hui Liu 《Cell research》2021,(4):415-432
Aging is a major risk factor for many diseases,especially in highly prevalent cardiopulmonary comorbidities and infectious diseases including Coronavirus Diseas... 相似文献
24.
25.
A PCR-Based Method for Monitoring Legionella pneumophila in Water Samples Detects Viable but Noncultivable Legionellae That Can Recover Their Cultivability 下载免费PDF全文
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27.
一氧化氮增加常氧和缺氧豚鼠心室肌细胞持续性钠电流 总被引:7,自引:1,他引:7
运用全细胞膜片钳记录缺氧条件下豚鼠心室肌持续性钠电流(INa.P)的变化及施加药物对其的影响,以探讨 INa.P 的本质及缺氧增大 INa.P 的机制。结果显示:(1)在常氧条件下,一氧化氮(NO)前体 L- 精氨酸(L-Arg)和供体硝普钠(SNP)浓度依赖性地增大INa.P; (2)INa.P 随缺氧时间延长而增大, 缺氧15 min 后施加 NO 合酶(NOS)抑制剂L- 硝基精氨酸甲酯(L-NAME), 不能使增大的INa.P 明显回复[(1.344 ±0.320) vs (1.301 ±0.317) pA/pF, P>0.05, n=5]; (3)缺氧时含L-NAME 的灌流液可使INa.P 明显减小,与单纯缺氧相比有显著差异[(0.914 ± 0.263), n=5 vs (1.344 ± 0.320) pA/pF, n=6, P<0.05], 但仍比常氧条件下增大[(0.914 ±0.263) vs (0.497 ±0.149) pA/pF, P<0.05, n=5]; (4)还原剂1,4-二硫代苏糖醇(DTT)不但可使L-Arg 及缺氧后施加SNP 增大的 INa.P 回复[(1.449 ± 0.522) vs (0.414 ± 0.067) pA/pF, P<0.01, n = 6 和(0.436 ± 0.141) vs (1.786 ± 0.636) pA/pF,P<0.01, n=5],而且使正常的 INa.P 减小[(0.396 ± 0.057) pA/pF vs (0.442 ± 0.056) pA/pF, P<0.01, n=6]。本实验结果表明缺氧可增大心室肌细胞的INa.P, 其作用机制可能是缺氧时心肌产生的NO 通过氧化细胞膜上钠通道蛋白所致,正常INa.P 的产生 相似文献
28.
Five new guaiane sesquiterpenes, 1 – 5 , were isolated from the culture broth of the endophytic fungus Xylaria sp. YM 311647, isolated from Azadirachta indica A. Juss . The structures of these compounds were elucidated on the basis of spectroscopic analyses, and their inhibitory activities against five pathogenic fungi were evaluated. All guaiane sesquiterpenes showed moderate or weak antifungal activities in a broth microdilution assay. 相似文献
29.
Zemliakova VV Strel'nikov VV Zborovskaia IB Balukova OV Maĭorova OA Vasil'ev EV Zaletaev DV Nemtsova MV 《Molekuliarnaia biologiia》2004,38(6):966-972
Multiplex methylation-sensitive PCR and methylation-specific PCR were employed in studying the methylation of CpG islands in the p16/CDKN2A and p14/ARF promoter and the first exon regions in non-small cell lung cancer (54 samples) and acute B-cell lymphoblastic leukemia (61 samples). Differences in methylation were detected between types of neoplasia as well as between CpG islands studied within the same types of tumors. High level of the p16/CDKN2A first exon CpC island methylation was revealed in non-small cell lung cancer (68%) and in acute B-cell lymphoblastic leukemia (55%) and the CpG island of p14/ARF first exon was nonmethylated in these types of tumors. The methylation of CpG-rich fragments of genes p16/CDKN2A and p14/ARF promoters was analysed. As was found out, CpG islands located in 5' areas of one and the same gene can differ in methylation frequencies. The comparison of sensitivity between methylation-specific PCR and methylation-sensitive PCR used in the methylations studies was carried out. 相似文献
30.
Functional & Integrative Genomics - DNAJ proteins function as co-chaperones of HSP70 and play key roles in cell physiology to promote protein folding and degradation, especially under... 相似文献