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1.
Summary NPY is a putative neurotransmitter mainly co-localized with noradrenaline in sympathetic fibers which innervate the cerebral vasculature. The origin of most of the perivascular NPY fibers seems to be in the superior cervical ganglion. To investigate involvement of Neuropeptide Y (NPY) mechanisms in subarachnoid haemorrhage (SAH), twenty patients with SAH were investigated. NPY-LI (-like immunoreactivity) levels in the external jugular vein were assessed using radioimmunoassay in blood samples collected postoperatively (or after SAH in non-surgical patients) on days 1, 2, 3, 5, 7 and 9. These levels were compared with the clinical course and blood flow velocity changes monitored with ultrasonic Doppler equipment from both middle cerebral arteries (MCA) and both internal carotid arteries (ICA).Compared to NPY-LI levels in 14 controls (mean 116±3 pmol/ l), increased levels (up to 253 pmol/l) and a close relationship between velocities and NPY-LI levels were found in a subpopulation of the SAH patients. When comparing the mean haemodynamic index (V MCA/ipsilateral V ICA) and mean NPY-LI levels in each of the 20 patients, a correlation of r=0.75, p=0.0001 was found. Increased NPY-LI were found (131±8 pmol/l) when simultaneous Doppler velocity recordings showed vasoconstriction (Haemodynamic index >5) compared with samples taken when the haemodynamic index was <5, p<0.05. When MCA velocity exceeded 120 cm/sec, increased levels were found (129±9 pmol/l) compared with the conditions when MCA velocity was less than 120 cm/sec (113±5 pmol/ l), p=0.06. The results indicate a possible NPY involvement in cerebral vasoconstriction after SAH.  相似文献   
2.
6186例脑卒中患者发病时间的季节性分析   总被引:3,自引:0,他引:3  
目的探讨青岛市区脑出血(CH)、脑梗死(CI)、蛛网膜下腔出血(SAH)发病时间的季节规律。方法收集青岛市1998年~2002年脑卒中患者6186例,其中CH1179人,CI4821人,SAH186人。圆分布分析探讨脑卒中患者发病时间的季节规律。结果CH冬季高发,平均角在1月份(P<0.05),男性患者的平均角在2月份(P<0.05),女性患者的平均角在1月份(P<0.05);CI秋季高发,男、女间无差别,平均角在10月份(P<0.05);SAH秋季高发,平均角在10月份(P<0.05),男性患者的平均角在9月份(P<0.05),女性患者的平均角在10月份(P<0.05)。结论青岛市的脑卒中发病具有季节性,在脑卒中预防工作中要充分考虑其发病的季节特点,并采取相应的措施。  相似文献   
3.
目的 探索地塞米松鞘内注射治疗蛛网膜下腔出血(SAH)头痛的适宜剂量。方法 所选病例分为4组,分别用0,5,10,20mg地塞米松鞘内注射观察止痛效果。结果 根据疗效判定标准,4组总有效率分别为25.00%,50.00%,92.31%,100.00%;头痛缓解时间随地塞米松(DXM)用量增加而延长。结论 DXM 10mg疗效比小剂量疗效高,与大剂量疗效;相同剂量越大缓解头痛时间越长。  相似文献   
4.
Summary The adenine nucleotide metabolites hypoxanthine, xanthine and uric acid were determined by high performance liquid chromatography in cerebrospinal fluid (CSF) from 25 patients with subarachnoid haemorrhage (SAH) and from 26 control subjects. In addition, the haemoglobin and protein levels in the CSF of the patients were determined.In 13 subjects, from which lumbar CSF was collected three, six and nine days after SAH, there was a gradual increase in 8 patients for hypoxanthine and in 3 of the 13 patients for xanthine and uric acid. The mean concentrations were not significantly higher than the controls. In 12 SAH patients, consecutive CSF fractions of 10 ml were collected peroperatively during surgical clipping of aneurysms. The hypoxanthine concentrations increased continously from lumbar to central CSF samples. Hypoxanthine levels were 6.5±1.0 M in lumbar CSF compared to 11.8±2.3 M in central CSF (p<0.001), while xanthine, uric acid, haemoglobin and protein levels were equally distributed. Furthermore, the SAH patients showed about 3 times higher concentrations of central CSF hypoxanthine (p<0.01) and xanthine (p<0.05) while that for uric acid was similar compared to all control subjects. Also, an in vitro study showed that the increased concentrations of the adenine nucleotide metabolites could not be caused by degradation of blood components in the subarachnoid space.It is presumed that the increased central CSF concentrations of hypoxanthine that were demonstrated in patients after SAH could be a sensitive marker for brain tissue ischaemia. However, since there was no correlation between the hypoxanthine levels, clinical condition or cerebral vascular diameter, other factors have to be excluded before ischaemia alone could explain the elevated central hypoxanthine levels in patients without major clinical dysfunction after SAH.This study was supported by grants from Karolinska Institutet, the Swedish National Society against Heart and Chest disease, The Swedish Society of Medical Sciences, Wibergs Foundation, Boehringer Ingelheim and the Swedish Medical Research Council (proj. no. 7485).  相似文献   
5.
目的探讨尼莫地平联合亚低温疗法治疗蛛网膜下腔出血(SAH)后脑血管痉挛的疗效。方法 93例SAH后脑血管痉挛患者随机分为两组。在常规治疗基础上,对照组采用亚低温疗法治疗,观察组采用尼莫地平联合亚低温疗法治疗。比较两组的治疗效果。结果观察组的总有效率为95.74%,高于对照组的80.43%(P <0.05)。治疗后,观察组的IL-6、 TNF-α、 hs-CRP水平均低于对照组,动脉平均血流速度高于对照组(P <0.05)。结论尼莫地平联合亚低温疗法治疗SAH后脑血管痉挛的效果显著,可有效抑制机体炎性反应,提升动脉平均血流速度。  相似文献   
6.
This paper investigates the role of biased health perceptions as a potential driving force of risky health behaviors. We define absolute and relative health perception biases, illustrate their measurement in surveys and provide evidence on their relevance. Next, we decompose the theoretical effect into its extensive and intensive margin: When the extensive margin dominates, people (wrongly) believe they are healthy enough to “afford” unhealthy behavior. Finally, using three population surveys, we provide robust empirical evidence that respondents who overestimate their health are less likely to exercise and sleep enough, but more likely to eat unhealthily and drink alcohol daily.  相似文献   
7.
Summary Clinical characteristics and the outcomes of 50 patients with confirmed subarachnoid haemorrhage (SAH) of unknown aetiology were evaluated. Twenty-nine of these patients were interviewed with a mean follow-up of 7.7 years. Seven patients experienced early rebleeding during hospitalization, and one patient experienced late rebleeding during the follow-up period.On admission to the hospital the consciousness level was clear in 43 of the patients, drowsy in 6, and semicomatose in only 1. Of 10 patients who underwent computerized tomography (CT) within 3 days after SAH, 6 showed no abnormal CT findings and 3 had mild subarachnoid blood. Another patient showed severe SAH. Neurological deficit due to symptomatic vasospasm persisted in only 1 case.Two patients died after re-bleeding during hospitalization, and two others died during the follow-up, thereby representing an overall mortality rate of 8%. Of the latter cases, one died of an unrelated disease, and the other died suddenly from an unknown cause. The remaining forty-six patients (92%) had a good outcome. These results confirm previously reported clinical characteristics, namely that the symptoms of the majority of such cases are mild, the incidence of symptomatic vasospasm is rare, the risk of late re-bleeding is very low (less than 1% per year), and the prognosis is good. The CT findings suggest that some of these features resulted from only mild SAH. Thus, SAH of unknown aetiology seems to be a disease entity with a good prognosis.  相似文献   
8.
Summary The effects of centrally administered atrial natriuretic peptide (ANP) on the brain water and electrolyte contents were investigated in a rodent subarachnoid haemorrhage (SAH) model. SAH caused statistically significant increases in the brain sodium and water contents, while the potassium content did not change significantly, indicating that the brain oedema could be classified as having a primarily vasogenic component. Two g or 5 g of rat ANP administered into the lateral ventricle at the time of SAH induction statistically significantly decreased the water and sodium accumulation measured 90 minutes following SAH. The same treatment did not inhibit development of brain oedema measured 3 hours following SAH. However, when 5 g of ANP was administered intraventricularly at the time of SAH induction and also 90 minutes later, the brain oedema 3 hours following SAH was again reduced statistically significantly. These effects of ANP were found not to be mediated by primary changes in serum osmolality and electrolyte concentrations.The present results confirm that centrally administered ANP may act directly on the central nervous system to inhibit brain water and sodium accumulation in SAH-induced brain oedema. The potentials of influencing the central neuro-endocrine system as a novel way of the treatment of brain oedema are discussed.Supported by Grant OTKA I/3 2728 and ETT T110/ 1990.  相似文献   
9.
Contrast media induced encephalopathy is a rare complication of contrast administration characterized by non-specific neurological signs and symptoms that may present both clinically and radiolographically as subarachnoid hemorrhage. While there are few reported presentations in the neurology literature after inpatient contrast administration, similar emergency department presentations have not been documented. We describe a patient who presented with encephalopathy and expressive aphasia after outpatient evaluation of an intrathecal analgesia pump who had radiographic imaging consistent with acute subarachnoid hemorrhage. The hyperdensities seen on computed tomography scanning were subsequently identified as residual gadolinium contrast media resulting in allergic encephalopathy in this patient.  相似文献   
10.
Parturition increases the risk of strokes of various types, including postpartum cerebral angiopathy (PCA), which is characterized by reversible multifocal vasoconstriction of the cerebral arteries. We describe an unusual presentation of PCA associated with postpartum non-aneurysmal subarachnoid hemorrhage (SAH). A 31-year-old multiparous woman complained of sudden headache 3 hours after an uncomplicated vaginal delivery. She had no history of pregnancy-induced hypertension. SAH was found over the bilateral frontoparietal convexities with multifocal vasculopathy. Her symptoms resolved completely within 1 week. The findings of a follow-up neurological examination, cerebral angiography, and brain MRI were normal after 2 months. PCA syndrome may be associated with postpartum non-aneurysmal SAH.  相似文献   
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