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991.
Twenty-four mongrel dogs were anaesthetized and ventilated mechanically in the supine position. Extravascular lung water (EVLW) and central blood volume (CBV) were measured with a double indicator (dye/cold) dilution technique. Both indicators were detected intravascularly in the aortic root with a fibreoptic thermistor catheter. Seven dogs ventilated with a positive end-expiratory pressure (PEEP) of 1.0 kPa (10 cmH2O) for a short period of time (less than 20 min) displayed no significant change in EVLW as measured with the indicator dilution technique (= EVLWi), while reductions were seen in both CBV (15%, P less than 0.01) and cardiac output (CO-thermodilution technique) (10%, P less than 0.05). Another seven dogs ventilated with a PEEP of 1.0 kPa for 8 h showed a gradual increase in EVLWi. After 8 h, a mean increase of 34% (P less than 0.01) was recorded, and the increase was also verified by post-mortem gravimetric determination of EVLW (= EVLWg), displaying an increase of 61% (P less than 0.01). In five dogs ventilated with zero end-expiratory pressure (ZEEP) for 8 h, no changes in EVLWi, CO, and CBV were observed, and EVLWg was mean 4.39 g/kg body weight (BW). Five additional dogs were sacrificed after 15 min of anaesthesia without catheterization and EVLWg was found to be 4.24 g/kg BW. It is concluded that EVLWi does not change measurably during ZEEP or short periods of PEEP. However, long periods (8 h) of PEEP result in elevated EVLWi values. Gravimetry supports these conclusions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
The mortality of cerebrovascular diseases in Denmark was analysed for men and women 15-44 years of age, in a 14-year period before and after the appearance of oral contraceptives (OC) in 1966. 1,670 deaths were registered over 28 years, during which the female incidence of cerebrovascular deaths increased by 19% (P less than 0.025), while the male mortality was unchanged. Women showed a percentage increase in deaths from cerebral thromboembolic attacks (CTA) of 33%, men a fall of 14%. The increase of female CTA deaths was most pronounced in the young fertile group, the age group with a high OC use. A relative risk of CTA of 3.3-4.5 for OC users compared with non-users could explain the CTA trend difference between women and men. No other single risk factor responsible for the observed trends could be identified. Both women and men had a significant increase in the mortality of subarachnoidal hemorrhages, and a significant fall in the mortality of intracerebral hemorrhages.  相似文献   
993.
特发性身材矮小儿童成骨细胞的功能状况   总被引:2,自引:2,他引:0  
目的通过检测特发性身材矮小(ISS)儿童血清骨碱性磷酸酶(BAP)及骨钙蛋白(OC)水平,探讨其成骨细胞的功能状况。方法ISS组36例及健康对照组儿童50例。ISS组分为青春期前组及青春期组。测各组儿童身高、体质量、体质量指数,采用CHN法评定左侧手、腕部骨化指标,计算骨龄。采用ELISA法测其血清BAP及OC水平。结果青春期前,ISS儿童血清BAP及OC水平为(79.90±25.96)U/Lvs(60.96±18.46)μg/L,健康对照组为(152.17±35.36)U/Lvs(76.16±28.03)μg/L;青春期,ISS儿童血清BAP及OC水平为(108.33±35.20)U/Lvs(63.82±24.81)μg/L,健康对照组为(156.30±35.29)U/Lvs(104.92±28.26)μg/L。青春期前及青春期ISS组血清BAP及OC水平均明显低于健康对照组,存在显著性差异(Pa<0.01)。结论ISS儿童以成骨细胞为中心环节的骨塑造和再造能力均较健康生长发育少年儿童差。  相似文献   
994.
A role of insular cortex in cardiovascular function   总被引:5,自引:0,他引:5  
We sought to determine whether the insular cortex contributes to the regulation of arterial blood pressure (AP). Responses to electrical and chemical stimulation of the cortex were studied in the anesthetized, paralyzed, and artificially ventilated Sprague-Dawley rat. The insular cortex was initially defined, anatomically, by the distributions of retrogradely labeled perikarya following injections of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the nucleus tractus solitarii (NTS). Injections of WGA-HRP into the insular cortex anterogradely labeled terminals in cardiopulmonary and other divisions of the NTS and confirmed projections revealed by retrograde tracing experiments. Electrical stimulation of the insular cortex elicited elevations of AP (less than or equal to 50 mm Hg) and cardioacceleration (less than or equal to 40 bpm). The locations of the most active pressor sites corresponded closely to the locations of retrogradely labeled cells in layer V of granular and posterior agranular areas of the insular cortex (areas 14 and 13) and the extreme capsule. Maximal pressor responses were obtained at a stimulus intensity of three to five times threshold current of 20-30 microA. Responses elicited mostly with higher-threshold currents were also mapped in areas 2a and 5lb and the claustrum and within the corpus callosum. Unilateral injections into the insular pressor area of the excitatory amino acid monosodium glutamate (L-Glu; 0.05 nmol to 10 nmol) or the rigid structural analogue of L-Glu, kainic acid (KA) (0.4 nmol) (which specifically excite perikarya), caused topographically specific elevations in AP and tachycardia. During the course of the anatomical transport studies, new findings were obtained on the organization and characteristics of the cortical innervation of the NTS and the nucleus reticularis parvocellularis. Topographic relationships between the cortex and the NTS were organized in a more complex manner than previously thought. Cells projecting to caudal cardiopulmonary segments of the NTS were fewer and generally located ventrally and caudally and in a more restricted area than cells projecting rostrally or to the parvicellular reticular formation. Anterograde transport data revealed new presumptive terminal fields in dorsolateral, ventral, periventricular, and commissural regions of the NTS, including an area overlapping the terminal field of the aortic baroreceptor nerve. We conclude that neurons within an area of the insular cortex projecting to multiple brainstem autonomic nuclei, including a region of the NTS innervated by baroreceptor afferents, increase arterial blood pressure and heart rate.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
995.
Objective: 5-Aminoisoquinolinone, a water-soluble, potent inhibitor of the activity of poly (adenosine 5'-diphosphate ribose) polymerase, plays an important role in the tissue injury associated with ischaemia-reperfusion injury and inflammation by inhibiting the activity of poly (adenosine 5'-diphosphate ribose) polymerase and the expression of cell adhesion molecules such as ICAM-1, P-selectin et al. But how about it in the tumor is not clear. The aim of the present study was to study the effects of 5-Aminoisoquinolinon on the adhesion of colon carcinoma line HT-29 cells to human umbilical vein endothelial cells; and the effects of 5-Aminoisoquinolinon on the expression of ICAM-1, P-selectin and the activity of poly (adenosine 5'-diphosphate ribose) polymerase in colon carcinoma HT-29 cells. Methods: The adhesion of HT-29 cells to human umbilical vein endothelial cells was detected by adhesive experiment. Immunocytochemically Streptavidin-Peroxidase method was used to investigate the expression of ICAM-1, P-selectin and Poly (adenosine 5'-diphosphate ribose)( the product of poly (adenosine 5'-diphosphate ribose) polymerase activation). Results: the results of the adhesion assay of HT-29 cells to HUVEC showed that the OD570 value in each 5-AIQ-treated group was significant lower than that in the control group (5-AIQ-untreated) in a dose-dependent manner. The expression of ICAM-1, P-selectin and Poly (adenosine 5'-diphosphate ribose) was significant lower in 5-Aminoisoquinolinone-treated HT-29 cell group than that in 5-Aminoisoquinolinoneuntreated groups. Conclusion: The data suggest that 5-Aminoisoquinolinone can inhibit the adhesion of HT-29 cells to human umbilical vein endothelial cells. 5-Aminoisoquinolinone also can inhibit poly (adenosine 5'-diphosphate ribose) polymerase activation and the expressions of ICAM-1 and P-selectin in HT-29 cells. 5-Aminoisoquinolinone probably contributes to the prevention of tumor cell metastasis. Further study is needed.  相似文献   
996.
妇幼保健院运营的模式,服务的对象都有别于综合性医院。通过对设备使用效益的调查、分析,提出妇幼保健院医疗设备的配置,应符合本院的特点。配置应遵循:适用性、特色性、经济性、先进性,不可盲目求新、求全,避免设备使用的低效益。  相似文献   
997.
艾灸对宫颈癌放疗患者血象影响的观察   总被引:4,自引:2,他引:2  
目的 探讨艾灸减轻放疗对宫颈癌患者血液系统损伤的作用。方法 61例宫颈癌患者分为艾灸治疗组、对照组,观察艾灸对宫颈癌放疗患者血象的影响。结果 艾灸能提高宫颈癌放疗患者的红细胞(P<0.05)、血色素(P<0.01)及血小板数,减轻放疗对白细胞的损害(P<0.01)。结论 艾灸具有抗放疗对宫颈癌(肿瘤)患者血液系统损害的作用,起到抗肿瘤、增强机体免疫功能、有利机体康复的作用。  相似文献   
998.
对人胎儿前庭器超微结构的研究,国内外报道甚少。本文对18至36周人胎儿颞骨10具进行了扫描电镜和透射电镜的观察,并对应用Surface preparation法制做人胎儿前庭器标本的方法进行了探讨。本文观察所见:豚鼠平衡斑的生理状态与人胎儿很近似,体面积比人胎儿平衡斑小,感觉毛长,细胞排列更整齐。28周以后的胎儿因前庭周围骨质变硬,制做标本时可以分别取出两囊斑和壶腹嵴。  相似文献   
999.
本文报道尿道损伤46例,占同期泌尿系损伤的70%。分析尿道损伤手术术式和疗效,以尿道对端吻合最好.尿道会师牵引术亦有其优点。  相似文献   
1000.
【目的】探索妊娠期精神压力对大鼠子代早期空间学习、记忆能力的影响。【方法】实验采取产前束缚压力,建立妊娠期大鼠精神压力暴露模型。然后对子代进行Morris水迷宫测试,分析妊娠期压力对子代早期学习和记忆的影响及性别间的差异,同时检测实验前、后子鼠的血清肾上腺酮的变化。【结果】①在隐蔽平台试验中,对照组的平均潜伏期较实验组短,但差异无显著性(F=0.599,P>0.05)。②在保持力试验中,对照组在原平台所在象限逗留的时间大于实验组,差异有显著性(F=4.588,P<0.05)。③子代血清肾上腺酮的测定结果表明:水迷宫测试前,实验组和对照组相比,差异无显著性(F=0.169,P>0.05);实验后,实验组血清肾上腺酮比对照组高,差异具有显著性(F=6.098,P<0.05)。【结论】①妊娠压力可导致子代学习,记忆能力的改变;②妊娠压力造成子代在应激情况下血清肾上腺酮的过度分泌。③妊娠压力对子代的影响没有明显性别差异。  相似文献   
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