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51.
We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit.  相似文献   
52.
The baroreflex maintains blood pressure through the glossopharyngeal (IX) cranial nerve. We report a 54-year-old man who developed a left sided headache, hoarseness, dysarthria, dysphagia, and sustained hypertension from a left internal carotid artery dissection. We hypothesise that interruption of the left IX nerve caused hypertension in this patient.  相似文献   
53.
The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension.  相似文献   
54.
R Tamura  T Ono  M Fukuda  H Nishijo 《Hippocampus》1992,2(3):287-306
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons.  相似文献   
55.
56.
Comprehensive renal function tests were performed in 84 patients with analgesic nephropathy, 33 glomerulonephritis patients matched for creatinine clearance, and 30 control subjects. A system of 1-day renal function tests including urine microscopy, creatinine clearance, phenolsulphonphthalein excretion, urine concentration and acidification, and electrolyte excretion, was used. Patients with analgesic nephropathy were found to have significant sterile pyuria and haematuria, even those with mild renal insufficiency, significantly reduced concentrating ability and a distal acidifying defect, and a tendency to impaired sodium conservation. These function defects are consistent with the primary lesion of renal papillary necrosis in analgesic nephropathy; the detection of these defects have implications in patient management.  相似文献   
57.
To detect early renal involvement in young diabetic patients (IDDM), urinary protein excretion and renal function were examined in 110 patients aged 5.9-25.0 years. Clearances of inulin and PAH were determined as well as albumin (Alb), IgG, N-acetyl-beta-D-glucosaminidase (NAG) and creatinine (Cr) excretion rates (UV). The patients were grouped according to IDDM duration (2- less than 5, 5-10 and greater than 10 years) and albumin excretion rate (non-albuminuria less than 20, microalbuminuria 20-200, and albuminuria greater than 200 micrograms/min per 1.73 m2). Four patients had overt albuminuria, 17 microalbuminuria (equally distributed among the duration groups). Grouped according to albumin excretion rate, the mean GFR was increased in those without albuminuria but 'normalized' in patients with microalbuminuria/albuminuria. Grouped according to albumin excretion rate and the duration of the disease, the non-albuminuric patients with IDDM for greater than 10 years had a lower GFR than those with a shorter duration of IDDM. The patients with microalbuminuria/albuminuria and IDDM for less than 5 years had a reduced GFR. Patients with increased NAG excretion rate had lower Na excretion rate, lower fractional Na excretion and greater creatinine excretion than those with normal NAG excretion. Albumin excretion correlated with IgG excretion, but also with NAG excretion. Our results suggest that early albuminuria in IDDM is of both glomerular and tubular origin. The hyperfiltration declines with increasing albumin excretion but also with the duration of the disease.  相似文献   
58.
Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.  相似文献   
59.
心脏搭桥术对糖尿病人降糖治疗方案的影响   总被引:1,自引:0,他引:1  
目的 :通过观察 型糖尿病 (DM- )行心脏冠脉搭桥术 (CABG)术后血糖水平的升高到恢复至术前状态的过程 ,从而判断 CABG对 DM- 降糖治疗的影响。方法 :选择 36例 DM- 合并冠心病病人 ,均于体外循环 (CPB)下行心脏搭桥术 ,从术前监测血糖 ,直至术后第七天 ,于术中及术后根据血糖水平适当应用胰岛素 ,观察其对降糖治疗效果及血糖趋于稳定的过程 ,从而判断 CABG对 DM- 血糖的影响。结果 :术中及术后 1~ 3d血糖会较术前明显升高 ,需加用胰岛素助降糖 ,术后 3d血糖渐降 ,第六天趋于稳定 ,第七天恢复至接近术前水平。结论 :DM- ,病人行 CABG术 ,只要围术期有效控制血糖 ,术后血糖基本会逐渐恢复至术前状态 ,对其今后的降糖治疗不会造成严重影响  相似文献   
60.
移植肾破裂的处理   总被引:4,自引:0,他引:4  
目的 提高移植肾破裂的防治水平。方法  6例移植肾破裂 ,手术前 2例 ,手术后 4例。 2例术前供肾破裂 ,采用切开移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。 1例术后移植肾破裂早期 ,出血少 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物。 3例术后移植肾破裂出血量估计超过 10 0 0ml者 ,采用手术延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。结果  ( 1)手术前 2例手术后 4例 ,采用切开或者延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾并配合“硝普钠”降压的方法处理 ,均未再破裂出血 ,移植肾功能恢复良好。 ( 2 ) 1例术后移植肾破裂早期的患者 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物 ,非手术治疗成功。结论  ( 1)采用手术切开或延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾可以有效治疗移植肾破裂。 ( 2 )移植肾破裂出血少的情况下 ,可以在密切观察下非手术治疗  相似文献   
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