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1.
The rat lumbar spinal cord contains a sexually dimorphic motor nucleus, the spinal nucleus of the bulbocavernosus (SNB), whose motoneurons innnervate perineal muscles involved in copulatory reflexes. Dendritic development of SNB motoneurons is biphasic and androgen dependent. During the first 4 postnatal weeks, SNB dendrites grow exuberantly, and subsequently retract to mature lengths by 7 weeks of age. After early postnatal castration, SNB dendrites fail to grow, and testosterone replacement restores this growth. In other systems, testosterone and its metabolites, dihydrotestosterone and estrogen, are important for somatic and neural sexual differentiation. The purpose of the present study was to examine the effects of castration and dihydrotestosterone or estrogen replacement on the growth of SNB motoneuron somata and dendritic arbors. Male rat pups were castrated on postnatal (P) day 7 and treated daily with either dihydrotestosterone propionate (DHTP; 2 mg) or estradiol benzoate (EB; 100 μg) until P28 or P49. By using cholera toxin horseradish peroxidase (BHRP) histochemistry, the soma size, dendritic length, dendritic extent, and arbor area of BHRP-labeled SNB motoneurons were measured and analyzed. Both DHTP and EB treatment supported the initial exuberant growth of SNB dendrites through P28, but EB treatment was ineffective in maintaining mature, adult lengths at P49. The possible sites of hormone action and functional implications of these hormonal treatments are discussed. 1994 John Wiley & Sons, Inc. 相似文献
2.
François Boutignon Hélène Touchet Sandrine David Patrick Wüthrich Romano Deghenghi Huy Ong Mélanie Dubuc Marina Cesana Tony Maggi 《Letters in Peptide Science》1997,4(4-6):423-427
Avorelin is a new superagonist of naturalluteinizing-hormone-releasing-hormone. Avorelin hasbeen formulated in high molecular weight polylactic glycolic acid to afford protracted andcontinuous release of the peptide from subcutaneousimplants. Two different formulations (10 and 15 mg)were tested first in dogs and then in men during aclinical phase II trial. Chemical castration wasmaintained for at least 6 months in dogs withboth formulations. A similar duration of activity(approximately 6 months) was observed in men. 相似文献
3.
Pedro Manuel Sánchez JuradoLuis Romero Rizos María Luisa García-Mauriño GuelbenzuPedro Abizanda Soler 《Revista espa?ola de geriatría y gerontología》2011,46(1):43
A case of primary pulmonary non-Hodgkin's lymphoma is presented. On this occasion, the lymphoma invaded the myocardium, an event which has not previously been reported in the literature. These neoplasms spread by proximity, and invasion of the pericardium, thoracic wall and oesophagus have been described. Our patient died from heart failure. Tumour myocardial infiltration may well have been the determinant cause through various mechanisms, including a decrease in myocardial contractility. Spread into the myocardium may be facilitated by bulky tumour infiltrates in the pleural space. 相似文献
4.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss
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Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
5.
Keqing Hu Xiaoqi Wang Hongyan Hu Zhongyang Xu Jiaxing Zhang Guipeng An Guohai Su 《Journal of cellular and molecular medicine》2020,24(8):4863-4870
Intracoronary application of nicorandil can effectively reduce the myocardial no‐reflow (MNR) after percutaneous coronary intervention (PCI). We sought to investigate the mechanisms of nicorandil in preventing MNR, besides that of dilating the coronary microvasculature. A total of 60 patients undergoing PCI were enrolled and randomly divided into a nicorandil group and a control group. Before PCI, 2 mg of nicorandil or an equal volume of normal saline was injected into the coronary artery. Blood samples were collected before, 24 hours and 1 week after PCI and inflammatory cytokines were tested. In the control group, the expression of pro‐inflammatory cytokines was significantly increased, while the anti‐inflammatory cytokines were decreased 24 hours after PCI. In contrast, these changes were reversed in the nicorandil group, indicating that nicorandil regulated the inflammatory response induced by PCI. Then, proteomic analysis was performed to further elucidate the potential mechanisms. A total of 53 differentially expressed proteins (DEPs) were found 24 hours after PCI in the control group, and the changes of these relevant genes were reversed in the nicorandil group. These DEPs were significantly enriched in the inflammatory pathways. In conclusion, the intracoronary application of nicorandil before PCI can regulate the inflammatory responses induced by PCI, which might be an important mechanism of nicorandil in preventing MNR. 相似文献
6.
Sarah Cusser Christie Bahlai Scott M. Swinton G. Philip Robertson Nick M. Haddad 《Global Change Biology》2020,26(6):3715-3725
Agricultural management recommendations based on short‐term studies can produce findings inconsistent with long‐term reality. Here, we test the long‐term environmental sustainability and profitability of continuous no‐till agriculture on yield, soil water availability, and N2O fluxes. Using a moving window approach, we investigate the development and stability of several attributes of continuous no‐till as compared to conventional till agriculture over a 29‐year period at a site in the upper Midwest, US. Over a decade is needed to detect the consistent effects of no‐till. Both crop yield and soil water availability required 15 years or longer to generate patterns consistent with 29‐year trends. Only marginal trends for N2O fluxes appeared in this period. Relative profitability analysis suggests that after initial implementation, 86% of periods between 10 and 29 years recuperated the initial expense of no‐till implementation, with the probability of higher relative profit increasing with longevity. Importantly, statistically significant but misleading short‐term trends appeared in more than 20% of the periods examined. Results underscore the importance of decadal and longer studies for revealing consistent dynamics and emergent outcomes of no‐till agriculture, shown to be beneficial in the long term. 相似文献
7.
Nomi Kreif Oleg Sofrygin Julie A. Schmittdiel Alyce S. Adams Richard W. Grant Zheng Zhu Mark J. van der Laan Romain Neugebauer 《Biometrics》2021,77(1):329-342
In studies based on electronic health records (EHR), the frequency of covariate monitoring can vary by covariate type, across patients, and over time, which can limit the generalizability of inferences about the effects of adaptive treatment strategies. In addition, monitoring is a health intervention in itself with costs and benefits, and stakeholders may be interested in the effect of monitoring when adopting adaptive treatment strategies. This paper demonstrates how to exploit nonsystematic covariate monitoring in EHR‐based studies to both improve the generalizability of causal inferences and to evaluate the health impact of monitoring when evaluating adaptive treatment strategies. Using a real world, EHR‐based, comparative effectiveness research (CER) study of patients with type II diabetes mellitus, we illustrate how the evaluation of joint dynamic treatment and static monitoring interventions can improve CER evidence and describe two alternate estimation approaches based on inverse probability weighting (IPW). First, we demonstrate the poor performance of the standard estimator of the effects of joint treatment‐monitoring interventions, due to a large decrease in data support and concerns over finite‐sample bias from near‐violations of the positivity assumption (PA) for the monitoring process. Second, we detail an alternate IPW estimator using a no direct effect assumption. We demonstrate that this estimator can improve efficiency but at the potential cost of increase in bias from violations of the PA for the treatment process. 相似文献
8.
目的:研究雄激素去势治疗联合多西他赛对晚期前列腺癌患者血清人激肽释放酶(hk2)、微核糖核酸-221(miR-221)及核转录因子-κB(NF-κB)水平的影响。方法:选择我院2014年9月~2016年1月收治的80例晚期前列腺癌患者为研究对象,依据随机数字表法分为对照组和实验组,各40例。对照组采用单纯雄激素去势治疗,实验组采用雄激素去势治疗联合多西他赛,对比两组临床疗效,治疗前后血清前列腺抗原(PSA),hk2、miR-221及NF-κB水平,生活质量,不良反应和生存情况。结果:治疗后,实验组总有效率显著高于对照组,差异有统计学意义(P<0.05)。治疗后,两组血清PSA、hk2、miR-221及NF-κB水平水平均显著低于治疗前,实验组以上指标明显低于对照组(P<0.05)。治疗后,实验组机体状况及生活状况较对照组高(P<0.05);两组家庭状况、情感状况、与医师关系及前列腺癌特异性生活质量评分比较差异无统计学意义(P>0.05)。治疗后,实验组机体状况及生活状况较对照组高(P<0.05);两组家庭状况、情感状况、与医师关系及前列腺癌特异性生活质量评分比较无统计学差异(P>0.05)。两组1年生存情况比较差异无统计学意义(P>0.05);实验组2年生存例数多于对照组(P<0.05)。结论:雄激素去势治疗联合多西他赛能够降低血清hk2、miR-221、NF-κB水平,改善患者生活质量及生存情况。 相似文献
9.
Human land-use changes are particularly extensive in tropical regions, representing one of the greatest threats to terrestrial biodiversity and a key research topic in conservation. However, studies considering the effects of different types of anthropogenic disturbance on the functional dimension of biodiversity in human-modified landscapes are rare. Here, we obtained data through an extensive review of peer-reviewed articles and compared 30 Neotropical bat assemblages in well-preserved primary forest and four different human-disturbed habitats in terms of their functional and taxonomic diversity. We found that disturbed habitats that are structurally less similar to primary forest (pasture, cropland, and early-stage secondary forest) were characterized by a lower functional and taxonomic diversity, as well as community-level functional uniqueness. These habitats generally retained fewer species that perform different ecological functions compared to higher-quality landscape matrices, such as agroforestry. According to functional trait composition, different bat ensembles respond differently to landscape change, negatively affecting mainly gleaning insectivorous bats in pasture, narrow-range species in cropland, and heavier animalivorous bats in secondary forest. Although our results highlight the importance of higher-quality matrix habitats to support elevated functional and taxonomic bat diversity, the conservation of bat species that perform different ecological functions in the mosaic of human-modified habitats also depends on the irreplaceable conservation value of well-preserved primary forests. Our study based on a pooled analysis of individual studies provides novel insights into the effects of different human-modified habitats on Neotropical bat assemblages. 相似文献
10.