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91.
Changes of the arterial plasma osmolality and of the glucose concentration were followed during a 30 min period of graded hemorrhagic hypotension (80, 50, and 30 mmHg) in the cat. Bleeding evoked a significant plasma hyperosmolality at all three hypotension levels and the responses were quantitatively related to the degree of hypotension. An approximate steady state increase in the arterial plasma osmolality was reached about 20 min after the start of the bleeding and it then averaged 8, 20, and 25 mOsm/kg H2O at 80, 50, and 30 mmHg, respectively. Bleeding also evoked an increase in the plasma glucose concentration, which almost entirely accounted for the observed hyperosmolality, especially at 80 and 50 mmHg. In late stages of hypotension at 30 mmHg, elevated plasma lactate and potassium concentrations contributed to the overall hyperosmolality. — Previous hemorrhagic hypotension experiments at 50 mmHg (Järhult 1975 b) have shown that hyperosmolality serves as an important regulator of the plasma and extracellular fluid volumes during bleeding. The present results indicate that such an osmolar compensatory mechanism is operating over wide ranges of hemorrhagic hypotension.  相似文献   
92.
Ovariectomized female rats were tested for sexual receptivity following SC priming with threshold doses of estradiol benzoate and intracerebral 27 ga implants of either progesterone or cholesterol. All females were repeatedly tested under both intracerebral hormone implant conditions. Cholesterol implants failed to activate receptivity, while progesterone implants in the interpeduncular-ventral tegmental area produced near maximal levels of receptivity within 30 min after implantation. Progesterone implants in the medial hypothalamus, anterior hypothalamus, preoptic area, pons, mesencephalic reticular formation and lateral mesencephalon failed to activate sexual receptivity.  相似文献   
93.
This investigation was designed to test (a) whether stimuli presented in the form of repeated blocks of habituation trials, as opposed to.1 single continuous series of stimuli, would produce a progressive decline. in amount of spontaneous recovery and trials to rehabituation of the skin conductance component of the orienting response; and (b) whether 30 or 50 post-habituation trials would produce a return of the orienting response which could be related In sensitization effects. Results showed that repeated habituations strengthened habituation as reflected in progressively decreasing spontaneous recovery across blocks, but not in speed of habituations. Further, neither 30 nor 50 post-habituation trials produced a return of the orienting response, although 30 such trials did result in increased skin conductance level. Discussion centers on whether habituation beyond asymptotic levels (‘below-zero’) within sessions was unambiguously obtained; relationships among stimulus intensity, frequency, and the return of the orienting response; and factors affecting measures of retention of habituation within sessions.  相似文献   
94.
The assumption that drugs used as unconditioned stimuli in conditioned taste aversion (CTA) studies act centrally was tested by comparing the effects of systemic and intracerebral injections of harmaline hydrochloride (H) in 340 rats. Intraperitoneal injection of 5–20 mg/kg but not of 2.5 mg/kg H administered 5 min after 15-min saccharin (0.1%) drinking decreased saccharin-water preference in a two-choice retention test, performed 48 h later, from 55% to 20%. Since CTA was not diminished when H (10 mg/kg) was injected into rats anesthetised immediately after saccharin drinking by pentobarbital (40 mg/kg), H (1.7–50 g) was administered intracerebrally to anesthetised rats fixed in the stereotaxic apparatus. Injection of 3–6 g H into the inferior olive elicited CTA comparable to that of systemic injection of 10 mg/kg H. Injections of 6 and 50 g H into cerebellum and bulbar reticular formation elicited weaker CTA while neocortical, hypothalamic and mesencephalic applications were ineffective. CTA could also be elicited when 50 g but not 6 g H was injected into the inferior olive 1 or 2 h after saccharin drinking. This delay-dependent effect and failure of non-contingent H administration to change saccharin preference indicates that the H-induced CTA is not contaminated by a non-specific increase in neophobia. It is concluded that H probably elicits CTA by activation of caudal bulbar structures, including the nucleus of the solitary tract, area postrema and lateral reticular formation.  相似文献   
95.
目的分析甘露醇联合吡拉西坦治疗脑出血致脑水肿患者的疗效及其安全性。方法选择2019年9月-2020年5月在沈阳市第五人民医院接受治疗的脑出血致脑水肿患者118例,按随机数字表法分为观察组和对照组各59例,两组入院后均实施常规治疗,在此基础上对照组予以甘露醇治疗、观察组给予甘露醇联合吡拉西坦治疗,比较两组的疗效、药物安全性,以及治疗前和治疗20d后神经功能和神经肽Y水平。结果观察组总有效率为98.31%,高于对照组的86.44%,差异有统计学意义(P<0.05)。治疗后两组美国国立卫生研究院卒中量表评分及神经肽Y水平均较治疗前下降,且观察组较对照组更低,差异有统计学意义(P<0.05)。观察组不良反应总发生率为8.47%,高于对照组的5.08%,但差异无统计学意义(P>0.05)。结论甘露醇联合吡拉西坦治疗脑出血致脑水肿的疗效较单独应用甘露醇更好,而且能够改善患者神经功能,安全性较高,值得推广。  相似文献   
96.
目的|探讨前列地尔联合尼莫地平治疗动脉瘤性蛛网膜下腔出血脑血管痉挛的效果。方法选取2017年6月--2019年12月沈阳市第五人民医院收治的76例动脉瘤性蛛网膜下腔出血脑血管痉李患者,依据治疗方式的不同将患者分为对照组和观察组各38例。对照组在常规治疗方案基础上加用尼莫地平治疗,观察组在对照组治疗方案基础上联合应用前列地尔。比较两组的治疗效果和用药期间不良反应发生情况,以及治疗前后脑中动脉血流速度和神经功能评分。结果观察组治疗效果及治疗后脑中动脉血流速度改善情况、神经功能评分均优于对照组,差异有统计学意义(P<0.05)。两组用药不良反应发生率差异无统计学意义(P>0.05)。结论前列地尔联合尼莫地平治疗动脉瘤性蛛网膜下腔出血脑血管痉李疗效确切,且不会增加药物不良反应,具有较好的临床应用价值。  相似文献   
97.
王林  李玉明  李皆 《河北医学》2001,7(8):675-678
目的:研究左旋精氨酸、牛磺酸、卡托普利单用及合用对自发性高血压大鼠的血压以及血神经肽Y、血脂水平的影响。方法:①用MRB-ⅢA型血压记录仪(上海第二医科大学高血压研究所),在大鼠清醒状态下,测鼠尾的尾动脉收缩压。②用酶法测定血清胆固醇(TC)、甘油三酯(TG)。③用^125I标记法和放射免疫法测血浆神经肽Y。结果:①经过四周药物治疗,左旋精氨酸且(L-arg)、牛磺酸组(Tau)血压均无变化(P>0.05)。卡托普利组(Cap )、三药合用组(L-arg Tau Cap)血压均下降(P<0.0005),L-arg Tau Cap组,血压下降比卡托普利组明显(P<0.01)。②经过四周药物治疗,牛磺酸组TC降低,TG无变化。L-arg Tau Cap组TC和TG均降低,左旋精氨酸组、卡托普利组TC和TG均无变化(P>0.05)。③经过四周药物治疗,左旋精氨酸组、牛磺酸组NPY无变化(P>0.05)。卡托普利组、L-arg Tau Cap 组NPY下降。用药前后,四组SHR大鼠血压高低与血浆神经肽Y的浓度均呈正相关(P<0.05)。结论:①四组大鼠治疗后,左旋精氨酸、牛磺酸组血压换变化;卡托普利组和合用组均出现血压降低,合用组降压效果经弹卡托普利明显。②牛磺酸治疗组血清胆固醇降低;三种药物合用组血清胆固醇和甘油三酯的降低。左旋精氨酸组、卡托普利组血脂无变化。③自发 性高血压大鼠的血压变化与血浆神经肽Y浓度的变化呈正相关,神经肽Y可能参与了高血压的发生发展。  相似文献   
98.
《Neuro-Chirurgie》2021,67(2):132-139
BackgroundMicro-arteriovenous malformations (micro-AVMs) are defined as AVMs just visible on angiography with a nidus size between 0.5 and 1 cm. Their principal manifestation is intracranial hemorrhage and their diagnosis and therapeutic management are still unclear.MethodsThe aim of our work was to show the clinical presentation, treatment and outcome of ruptured cerebral micro-AVMs in a retrospective cohort study of 19 patients and a systematic review of the literature.ResultsWe obtained a total of 20 micro-AVMs in 19 patients. The mean age was 47.3 years. Clinical presentation was acute bleeding. The mean volume of hematoma was 12.9 mm3 (0 - 60.4), with topographic distribution as follows: 64% cortical with supratentorial bleeding, 26% deep, and 10% in the posterior fossa. Among the 20 micro-AVMs of the series, 11 (55%) had endovascular management, 6 (30%) had surgical treatment and 3 (15%) had GK radiosurgery alone. All of our patients have been cured at the end of the follow up without re-permeabilization. In our series, clinical outcome showed good recovery with a mean score of 4.6 on Glasgow Outcome Scale (GOS). In the literature, 88% of patients had a GOS of 4 or 5.DiscussionIntracerebral hematoma (ICH) was the main clinical manifestation. In the case of negative initial angiographic assessment, patients must have supraselective angiographic exploration. In the case of conservative treatment of hematoma, endovascular obliteration and microsurgical exclusion seems to be reasonable therapeutic options, according to our observations.  相似文献   
99.
出生队列是研究生命早期暴露对健康结局影响的重要工具, 但目前缺乏有力支撑孕前暴露特别是父系暴露对生殖健康和妊娠结局影响研究的大型队列平台。重庆市孕前生殖健康与出生结局队列研究是起始于孕前阶段, 同等关注男女双方的环境、心理、行为等暴露因素对生殖健康和不良妊娠结局影响的前瞻性队列研究。项目于2019年正式启动, 计划招募有生育意愿的育龄夫妇20 800人。通过随访, 调查志愿者2年内是否自然受孕。对进入妊娠期的女性志愿者, 在孕早、中、晚期进一步随访, 并对分娩的子代随访至2岁, 监测早产、低出生体重、出生缺陷、神经功能发育障碍等结局发生情况。各阶段分别采集相应的数据信息和生物样本, 包括精液、外周血、尿液、胎盘、脐带、脐带血、口腔拭子等。截至2022年1月, 已纳入志愿者8 698人, 分布于重庆市所有38个区/县。本队列建设目标是成为涵盖父母双方的前瞻性大样本孕前出生队列, 将以独特的设计和更加全面的视角阐明全生育周期特别是孕前期暴露因素对生殖健康和不良出生结局的影响及机制。  相似文献   
100.
IntroductionAtraumatic splenic rupture is a rare but life-threatening condition which may be associated with hematological malignancies.Presentation of caseWe present the case of a 63-year-old male patient with a history of chronic myelomonocytic leukemia and sarcoidosis under therapy with prednisone, who suffered an atraumatic splenic rupture with hemodynamic instability. He was managed with proximal splenic artery embolization and secondary open splenectomy. On pathology the diagnosis of peliosis lienalis was established.DiscussionPeliosis is a rare pathological entity, which presents with multiple blood-filled cavities within parenchymatous organs and is of unknown etiology and pathogenesis. In retrospect a rapid increase in splenomegaly and inhomogeneous parenchyma of the spleen on sonography was realized.ConclusionSonographic changes in size and parenchyma of the spleen in patients with hematological malignancies might help suspecting peliosis lienalis with impending splenic rupture and could alter clinical management towards a prophylactic splenectomy.  相似文献   
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