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21.
王海庆欧阳军 《现代生物医学进展》2011,11(3):441-443
目的:观察不同液体复苏对失血性休克大鼠肠粘膜的影响以及肠粘膜的变化。方法:利用大鼠失血性休克模型以及不同的补液方式,在复苏后120分钟时处死大鼠,取回肠4cm,做病理切片并根据Chiu等方法评估回肠黏膜上皮损伤指数。结果:液体复苏组的肠粘膜损伤程度小于休克不补液组(p<0.05),而限制型液体复苏组的肠粘膜损伤程度小于充分液体复苏组(p<0.05)。结论:通过本实验对肠粘膜的观察可以得出,对于失血性休克,液体复苏时有效的抗休克方式,而对于复苏的方式来说,从肠黏膜的保护方面来说,限制型液体复苏是优于传统的充分液体复苏的。 相似文献
22.
《Animal : an international journal of animal bioscience》2022,16(10):100639
Hypocalcaemia prevention programmes have been widely studied in experimental settings, but their feasibility has not been assessed under field conditions. The main objective of this study was to evaluate, in the context of small dairy farms in western France, whether and how dairy farmers implement prevention programmes and manage the feeding of dry cows to prevent hypocalcaemia. Seventy-nine commercial Holstein dairy farms in Brittany (France) were enrolled in a qualitative study in 2019. We conducted in-person interviews with the farmers to 1) understand the rationale behind the type and seasonality of prevention programmes they implemented and 2) assess how closely they followed common recommendations when implementing them. Most farmers (80 %) used at least one prevention programme, especially supplying a mineral mix formulated to meet the needs of dry cows in late gestation (53 %), acidifying the diet in late gestation (37 %), and supplying calcium at calving (oral or injectable form, 37 %). The use of programmes depended on whether the diet composition varied throughout the year. Among farmers who provided an acidified diet, 25 % did not supply a specific mineral mix to dry cows to ensure an adequate amount of P, Ca, and Mg, which could decrease the effectiveness of the acidification programme. A lack of reliability in feeding practices, such as not weighing feed or not delivering feed frequently enough, was identified for 61 % of contributing farms. Management practices could result in supplying an unsuitable amount of P, Ca, or Mg immediately before calving; for example, inappropriate batching practices around calving were identified for 22 % (cows) to 32 % (heifers) of farms. In addition, nearly all contributing farmers had no processes in place to monitor the effectiveness of the programmes implemented. Reasons for this overall lack of compliance should be explored. 相似文献
23.
24.
《Cell reports》2020,30(1):153-163.e5
25.
本文用脑室灌注和Fura2测定细胞内游离钙技术观察了地塞米松(dexamethasone,DEX)对家兔乙二醇双(2氨基乙醚)四乙酸性发热效应和下丘脑细胞内游离钙浓度([Ca2+]i)的影响,借此深入探讨地塞米松解热作用的中枢机制。结果发现:脑室灌注乙二醇双(2氨基乙醚)四乙酸(06nmol)引起家兔结肠温度明显升高,静脉注射地塞米松(5mg/kg)显著抑制家兔乙二醇双(2氨基乙醚)四乙酸性发热,地塞米松(60~120μmol/L)并不影响下丘脑细胞内[Ca2+]i,而事先脑室灌注抑制基因转录的放线菌素D(3nmol)则完全取消了地塞米松对乙二醇双(2氨基乙醚)四乙酸性发热的解热作用。这些结果提示:地塞米松显著抑制家兔乙二醇双(2氨基乙醚)四乙酸性发热,其机制与地塞米松激活脑内某些基因的表达有关,而与下丘脑神经细胞跨膜钙离子流无关。 相似文献
26.
埃博拉出血热是由埃博拉病毒引起的一种急性出血性传染病,具有极高的传染性,致死率高达50%~88%,目前对埃博拉出血热的预防还极为困难,暂无有效的抗病毒药物和疫苗。构建埃博拉出血热的动物模型,对于病毒致病机理的了解和深入研究,以及治疗药物及疫苗的研发具有至关重要的作用。 相似文献
27.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
28.
Role of the nitric oxide/cyclic GMP/Ca2+ signaling pathway in the pyrogenic effect of interleukin-1β
Interleukin-1β (IL-1β) has a wide spectrum of inflammatory, metabolic, haemopoietic, and immunological properties. Because
it produces fever when injected into animals and humans, it is considered an endogenous pyrogen. There is evidence to suggest
that Ca2+ plays a critical role in the central mechanisms of thermoregulation, and in the intracellular signaling pathways controlling
fever induced by IL-1β and other pyrogens. Data from different labs indicate that Ca2+ and Na+ determine the temperature set point in the posterior hypothalamus (PH) of various mammals and that changes in Ca2+ and PGE2 concentrations in the cerebrospinal fluid (CSF) of these animals are associated with IL-1β-induced fever. Antipyretic drugs
such as acetylsalicylic acid, dexamethasone, and lipocortin 5-(204–212) peptide counteract IL-1β-induced fever and abolish
changes in Ca2+ and PGE2 concentrations in CSF. In vitro studies have established that activation of the nitric oxide (NO)/cyclic GMP (cGMP) pathway
is part of the signaling cascade transducing Ca2+ mobilization in response to IL-1β and that the ryanodine (RY)- and inositol-(1,4,5)-trisphosphate (IP3)-sensitive pools are the main source of the mobilized Ca2+. It is concluded that the NO/cGMP/Ca2+ pathway is part of the signaling cascade subserving some of the multiple functions of IL-1β. 相似文献
29.
Biological invasions can have severe and widespread impacts on ecological communities. A few species of ants have become particularly
damaging invaders but quantitative data of their impacts on many taxa is still lacking. We provide experimental evidence using
artificial nests baited with quail eggs that the invasive Argentine ant (Linepithema humile) can be a significant avian nest predator – Argentine ants recruited to more nests and in higher abundance than the native
ant species they displace. However, at a site invaded by Argentine ants, we monitored over 400 nests of a ground-nesting species,
the Dark-eyed Junco (Junco hyemalis), and found that less than 2% of nests failed as a result of Argentine ant predation/infestation. A review of the literature
also suggests that Argentine ants may not be a serious threat to bird nests relative to other predators or parasites. However,
invasive ants with the capability of overwhelming prey though stinging (specifically the red-imported fire ant, Solenopsis invicta), may have a higher impact on avian nesting success.
Received 14 January 2005; revised 28 April 2005; accepted 12 May 2005. 相似文献