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101.
The pattern of 72-kDa heat shock protein-like immunoreactivity in the rat brain following flurothyl-induced status epilepticus 总被引:8,自引:0,他引:8
The inducible 72-kDa heat shock protein (HSP72) is a highly conserved stress protein that is expressed in CNS cells and may play a role in protection from neural injury. We used a monoclonal antibody to HSP72 and immunocytochemistry to localize HSP72 in the rat brain 24 h following either 30 or 60 min of flurothyl-induced status epilepticus. Sprague-Dawley rats were anesthetized with halothane, paralyzed, and ventilated, and remained normotensive and well oxygenated for the duration of the seizures. Seizure activity was quantified via analysis of the scalp EEG pattern. HSP72-like immunoreactivity (HSP72-LI) was induced in specific brain regions in a graded fashion that correlated, in part, with the duration and degree of seizure activity. Milder seizures produced HSP72-LI limited to layers 2 and 3 of frontoparietal cortex, dentate hilus cells, and CA3 pyramidal neurons. More extensive seizures led to HSP72-LI in layers 2, 3 and 5 of frontoparietal and visual cortex, dentate hilus cells, CA1 and CA3 pyramidal neurons, and certain thalamic and amygdaloid nuclei. These are similar to many, but not all, of the brain regions known to be injured with this model. No HSP72-LI was observed in sham-treated controls or flurothyl-treated animals whose seizures were controlled with pentobarbital. HSP72-LI thus localizes to certain regions of seizure-induced injury, and may provide a sensitive method of detecting neuronal 'stress' or injury relatively soon after status epilepticus. Whether or not HSP72 synthesis plays a protective role in the pathogenesis of seizures, or is only a marker for cell injury, remains to be determined. 相似文献
102.
103.
Is anesthesia beneficial for the ischemic heart? III 总被引:1,自引:0,他引:1
104.
A. Lowenstein 《Zeitschrift für Gerontologie und Geriatrie》1999,6(2):398-406
A parallel process to the aging of societies in the Western world occurs in changing family structures and network compositions. The shape of families is shifting from horizontal to vertical, where the size of generations is becoming smaller but the number of living generations is increasing. Recently there is an increased emphasis in the study of intergenerational relations on the independence of generations. The “aging of the aged”, though, means the need for more care and support. It is well documented that there is continued high involvement of families in care giving. However, as the age structure of the society and the family change so does the availability and ability for care of its networks. The presentation will, thus, discuss and analyze the following three issues: First, a theoretical perspective on family intergenerational relationships will be presented, based on social exchange theory and the intergenerational solidarity model. Empirical findings will focus on grandparent-grandchild relations and on immigrant families, stressing the importance of ethnicity. Second, care giving and support to frail elderly family members, in different types of living arrangements, will be described and analyzed, as a major topic in research and policy. Third, the relations and impact of family solidarity, support and care on the quality of life of the older people will be discussed. 相似文献
105.
J E Naschitz L Gaitini L Lowenstein D Keren A Tamir D Yeshurun 《Journal of human hypertension》1999,13(7):443-447
We propose a rapid method for the evaluation of automatic blood pressure measurement devices (READ) in response to the claim to simplify the validation of those devices. The READ is based on numerous blood pressure (BP) measurements at rest and during a standardised postural challenge in a small number of subjects who exhibit a wide range of BPs. Automatic (AU) and mercury sphygmomanometric (MS) brachial BP were measured simultaneously in a blinded manner. An average of 30 measurements per patient were done in 10-min while in a supine position, followed by 30 min in head-up tilt and again supine for 10 min. Two Collin-8800 automated oscillometric devices were tested with the aid of the READ in 15 adults. The consistency of the MS standard was demonstrated by duplicate MS measurements showing minimal inter-observer differences consistent with class A of the British Hypertension Society (BHS) grading system. AU-to-MS differences of 447 measurements were mean systolic deltaBP = 1.1 +/- 11.4 mm Hg and mean diastolic deltaBP = -13.36 +/- 8.9 mm Hg, classifying into category D of the BHS. Both tested instruments, each subject, each phase of the tilt test (supine I, tilt, supine II) and each mode of measurement (at 5-min intervals or continuously) equally qualified as 'D'. We conclude that the READ permitted us to identify quickly and at low expense a grossly inaccurate automatic BP measuring device. Further studies will show whether the READ can be efficient as a pre-validation test, post-validation test, and for assessment of ambulatory BP measuring devices. 相似文献
106.
BACKGROUND: Determinants of myocardial blood flow distribution include metabolic, myogenic, endothelial, and neurohumoral control mechanisms. The authors studied the effect of sevoflurane and desflurane on the myogenic and endothelial mechanisms. METHODS: Wistar rat subepicardial microvessels, approximately 100 microm in diameter, were monitored for diameter changes in vitro using a video detection system. Myogenic vasomotion was studied by varying the intraluminal pressure from 10 mmHg to 120 mmHg. Flow-induced, endothelium-dependent dilation was evaluated in U46619-preconstricted vessels by varying the pressure gradient across the isolated vessel from 10 mmHg to 80 mmHg, while maintaining the midpoint luminal pressure constant at 40 mmHg to avoid myogenic effects. Myogenic and flow-induced vasomotion both were studied in the presence of sevoflurane, 1 or 2 minimum alveolar concentration (MAC) (MAC is a unit of inhalational anesthetic potency), desflurane, 1 or 2 MAC, or no anesthetic (control). RESULTS: Myogenic constriction was shown above intraluminal pressures of 70 mmHg. Myogenic constriction was unchanged by sevoflurane, 1 MAC (P = 0.24), but was mildly enhanced by sevoflurane, 2 MAC (P < 0.05), or desflurane, 1 (P < 0.05) or 2 MAC (P < 0.01). Flow-induced dilation was shown over the pressure gradient range of 10-80 mmHg. Flow-induced dilation was not altered significantly by sevoflurane, 1 or 2 MAC (P > 0.3 each), but was significantly attenuated by desflurane, 1 or 2 MAC (P < 0.001 each). CONCLUSIONS: Sevoflurane maintains myogenic and endothelial determinants of myocardial blood flow distribution. Conversely, desflurane attenuates endothelium-dependent flow-induced dilation while mildly enhancing myogenic constriction. 相似文献
107.
108.
The relationships between personal resources of elderly parents and intergenerational interactions were studied. On the basis of a fourfold typology of intergenerational exchange, it was hypothesized that the amount of parents' resources, including familial, economic, physical and cognitive resources, would be differentially related to three exchange types: instrumental aid, shared leisure, and affective relations. Data were collected from 145 Jewish elderly persons residing in the community, through structured personal interviews, and analyzed by a stepwise multiple regression procedure. The findings show the multidimensionality of intergenerational bonds, and support the hypothesis that the amount of personal resources is positively related to expressive interactions and inversely to instrumental aid. 相似文献
109.
目的探讨医源性脾脏损伤脾切除对结直肠癌切除患者术后长期生存的影响。方法对1990年1月1日至1999年12月31日10年间行结直肠癌手术切除并附带脾切除患者进行病例配对回顾研究。分析患者年龄、性别、依据美国麻醉学医师协会(ASA)标准评估的身体状况、疾病分期、手术类型及预后等资料。配对病例来自同一医疗中心,性别、年龄、疾病分期及手术类型完全相同。手术附带脾切除患者为试验组,未切脾者为对照组。结果55例患者行医源性脾切除术,对照组在年龄、性别、身体状况、疾病分期及手术类型上与之匹配。随访时间(从手术开始到患者死亡或者最后一次随访1为2~205个月(中位随访时间为43个月)。Cox比例危险度模型进行Kaplan-Meier法生存分析发现两组间差异有显著性意义,不切除脾脏对患者生存有利(危险度1.8,95%可信区间为1-3.3,P=0.0399),未切脾组与切脾组5年生存率分别为70%和47%,10年生存率分别为55%和38%。结论结直肠癌患者在行结肠或直肠切除时,因医源性脾脏损伤而切除脾脏者,预后较差。 相似文献
110.
Superparamagnetic iron oxide-enhanced MR imaging: pulse sequence optimization for detection of liver cancer 总被引:3,自引:0,他引:3
Fretz CJ; Elizondo G; Weissleder R; Hahn PF; Stark DD; Ferrucci JT Jr 《Radiology》1989,172(2):393-397
The effects of magnetic resonance (MR) pulse sequences and timing parameters on tumor-liver contrast were studied in an animal model of metastatic liver cancer. Six spin-echo (SE), three inversion-recovery (IR), and four gradient-echo (GRE) sequences were evaluated at 0.6 T before and after injection of super-paramagnetic iron oxide. GRE techniques, irrespective of echo time and flip angle, showed the greatest change in signal intensity (enhancement) of the liver after administration of iron oxide. Single-acquisition GRE sequences (16 seconds) matched the contrast-to-noise ratio (C/N) performance of the most effective 6.4-minute SE sequences. Multiexcitation GRE sequences showed tumor-liver C/Ns per unit time that were significantly (P less than .05) higher than those achieved with SE and IR sequences. GRE sequences, which recruit intravoxel dephasing as an additional source of transverse relaxation enhancement (T2*), show a higher C/N per unit time and in this respect seem superior to SE and IR sequences for MR imaging with superparamagnetic iron oxide. 相似文献