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101.
Real time, B mode ultrasound was used from Days 18 to 64 to detect and monitor the conceptus in 30 unknown breeds of Bos indicus recipients following embryo transfer. The embryonic vesicle was first visible within the uterus between Days 18 and 20 (mean +/- SD 18.5 +/- 0.7d) d). The embryo proper was detected at Day 19.5 +/- 0.7. The heartbeats were detected at Day 22.6 +/- 0.9. The average day of first detection of the allantois, the C - shaped embryo and the amnion was 23.1 +/- 0.8, 23.8 +/- 1.4 and 25.1 +/- 1.4 d, respectively. The fore limb, the limb buds, the spinal cord and the optic area were observed on Days 32.7 +/- 1.3, 32.9 +/- 1.3, 33.0 +/- 1.5 and 33.6 +/- 1.4, respectively. Fetal movements could be detected at Day 50.7 +/- 1.0. Ribs and vertebrae were detected on Day 60.9 +/- 1.7. The mean length of the embryo proper was 4.5 +/- 0.8 mm. on Day 19. At Day 60 it was 52.5 +/- 7.0 mm. The growth of the embryo proper increased steadily until Day 39, growing rapidly thereafter. Embryonic death was detected in one recipient on Day 32. The echongenic area started increasing and recipient appeared in estrus on Day 40. Sixteen recipients exhibited estrus on Days 22 to 24. An increase in intrauterine fluid was observed on Days 18 to 24. 相似文献
102.
J. Taneja P. M. Guerin 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,181(1):21-34
1) Nymphs of the haematophagous bug Triatoma infestans (Heteroptera: Reduviidae) are attracted to volatiles from their own faeces on a servosphere. 2) Biological substrates attractive
to triatomines release NH3: wetted triatomine faecal papers release NH3 at 256 ppb NH3 from a 60-g source and stale rabbit urine at 394 ppb from 200 ml. Ammonia released from aqueous NH3 also attracts bugs at doses of 3 ppb and 17 ppb on the servosphere. 3) Bugs typically show negative anemotaxis in a stimulus-free
air-stream on the servosphere. At onset of stimulation with ammonia from either biological substrates or aqueous NH3 the bugs stop, move their antennae, turn and walk upwind, i.e. odour-mediated anemotaxis. 4) At lower NH3 doses a latency in attraction is recorded, but this latency disappears when the relative humidity of the stimulus delivery
air-stream is dropped from 90 to 35%. 5) Electrophysiological recordings from single olfactory sensilla on antennae of Triatoma nymphs reveal two different types of NH3-excited receptors, both within grooved-peg sensilla. The responses of one of these receptor cells to NH3 has been studied in detail and shows that the action potential discharge rate is dose-dependent over the range 2–200 ppb.
6) The amplitudes of electroantennograms recorded from Triatoma nymphs to NH3 are dose dependent over the range 5–550 ppb.
Accepted: 16 January 1997 相似文献
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107.
Bhushan S Kumar A Malik F Andotra SS Sethi VK Kaur IP Taneja SC Qazi GN Singh J 《Apoptosis : an international journal on programmed cell death》2007,12(10):1911-1926
A triterpenediol (TPD) comprising of isomeric mixture of 3α, 24-dihydroxyurs-12-ene and 3α, 24-dihydroxyolean-12-ene from
Boswellia serrata induces apoptosis in cancer cells. An attempt was made in this study to investigate the mechanism of cell death by TPD in
human leukemia HL-60 cells. It inhibited cell proliferation with IC50 ∼ 12 μg/ml and produced apoptosis as measured by various biological end points e.g. increased sub-G0 DNA fraction, DNA ladder
formation, enhanced AnnexinV-FITC binding of the cells. Further, initial events involved massive reactive oxygen species (ROS)
and nitric oxide (NO) formation, which were significantly inhibited by their respective inhibitors. Persistent high levels
of NO and ROS caused Bcl-2 cleavage and translocation of Bax to mitochondria, which lead to loss of mitochondrial membrane
potential (Δψm) and release of cytochrome c, AIF, Smac/DIABLO to the cytosol. These events were associated with decreased expression of
survivin and ICAD with attendant activation of caspases leading to PARP cleavage. Furthermore, TPD up regulated the expression
of cell death receptors DR4 and TNF-R1 level, leading to caspase-8 activation. These studies thus demonstrate that TPD produces
oxidative stress in cancer cells that triggers self-demise by ROS and NO regulated activation of both the intrinsic and extrinsic
signaling cascades. 相似文献
108.
Tae Hoon Kim Jung-Yoon Yoo Zhong Wang John P. Lydon Shikha Khatri Shannon M. Hawkins Richard E. Leach Asgerally T. Fazleabas Steven L. Young Bruce A. Lessey Bon Jeong Ku Jae-Wook Jeong 《PLoS genetics》2015,11(9)
AT-rich interactive domain 1A gene (ARID1A) loss is a frequent event in endometriosis-associated ovarian carcinomas. Endometriosis is a disease in which tissue that normally grows inside the uterus grows outside the uterus, and 50% of women with endometriosis are infertile. ARID1A protein levels were significantly lower in the eutopic endometrium of women with endometriosis compared to women without endometriosis. However, an understanding of the physiological effects of ARID1A loss remains quite poor, and the function of Arid1a in the female reproductive tract has remained elusive. In order to understand the role of Arid1a in the uterus, we have generated mice with conditional ablation of Arid1a in the PGR positive cells (Pgr
cre/+
Arid1a
f/f; Arid1a
d/d). Ovarian function and uterine development of Arid1a
d/d mice were normal. However, Arid1a
d/d mice were sterile due to defective embryo implantation and decidualization. The epithelial proliferation was significantly increased in Arid1a
d/d mice compared to control mice. Enhanced epithelial estrogen activity and reduced epithelial PGR expression, which impedes maturation of the receptive uterus, was observed in Arid1a
d/d mice at the peri-implantation period. The microarray analysis revealed that ARID1A represses the genes related to cell cycle and DNA replication. We showed that ARID1A positively regulates Klf15 expression with PGR to inhibit epithelial proliferation at peri-implantation. Our results suggest that Arid1a has a critical role in modulating epithelial proliferation which is a critical requisite for fertility. This finding provides a new signaling pathway for steroid hormone regulation in female reproductive biology and furthers our understanding of the molecular mechanisms that underlie dysregulation of hormonal signaling in human reproductive disorders such as endometriosis. 相似文献
109.
Administration of IκB‐kinase inhibitor PS1145 enhances apoptosis in DMBA‐induced tumor in male Wistar rats
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110.
I Saba PH Qazi SA Rather RA Dar QA Qadri N Ahmad S Johri SC Taneja S Shawl 《World journal of microbiology & biotechnology》2012,28(3):1071-1079
A Psychrotolerant alkaline protease producing bacterium IIIM-ST045 was isolated from a soil sample collected from the Thajiwas
glacier of Kashmir, India and identified as Stenotrophomonas sp. on the basis of its biochemical properties and 16S ribosomal gene sequencing. The strain could grow well within a temperature
range of 4–37°C however, showed optimum growth at 15°C. The strain was found to over-produce proteases when it was grown in
media containing lactose as carbon source (157.50 U mg−1). The maximum specific enzyme activity (398 U mg−1) was obtained using soya oil as nitrogen source, however, the inorganic nitrogen sources urea, ammonium chloride and ammonium
sulphate showed the lowest production of 38.9, 62.2 and 57.9 U mg−1. The enzyme was purified to 18.45 folds and the molecular weight of the partially purified protease was estimated to be ~55 kDa
by SDS-PAGE analysis. The protease activity increased as the increase in enzyme concentration while as the optimum enzyme
activity was found when casein (1% w/v) was used as substrate. The enzyme was highly active over a wide range of pH from 6.5
to 12.0 showing optimum activity at pH 10.0. The optimum temperature for the enzyme was 15°C. Proteolytic activity reduced
gradually with higher temperatures with a decrease of 56% at 40°C. The purified enzyme was checked for the removal of protein
containing tea stains using a silk cloth within a temperature range of 10–60°C. The best washing efficiency results obtained
at low temperatures indicate that the enzyme may be used for cold washing purposes of delicate fabrics that otherwise are
vulnerable to high temperatures. 相似文献