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11.
Summary Focal cerebral ischemia was induced by occlusion of the right middle cerebral artery in hypoglycemic, normoglycemic, as well as in acute and chronic diabetic rats. The brain damage was studied after 4 days. The volume of infarction was decreased in hypoglycemia (29±19 mm3 (mean±SD) versus 58±35 mm3,P<0.0046), unaltered in acute diabetes (61±45 mm3), and increased in chronic diabetes (91±22 mm3,P<0.0463). The cortex adjacent to the infarct showed selective neuronal injury affecting the cortical layers 2 and 3. The damage was enhanced by hypoglycemia and prevented in most of the diabetic animals. The findings indicate that different mechanisms cause infarction and selective neuronal injury outside infarcts, but that both are influenced by the plasma glucose concentration.  相似文献   
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13.
Between March 1990 and March 1993 some 822 consecutive patients underwent an attempt at laparoscopic cholecystectomy. Intravenous cholangiography (IVC), ERCP, and selective intraoperative cholangiography (IOC) were used in the evaluation of common bile duct (CBD) stones. Two hundred thirteen patients (26%) were identified preoperatively with either abnormal liver functions or a dilated common bile duct suggestive of CBD stones. IVC was performed in 143 patients (67%). Choledocholithiasis was identified in 14 patients (10%). Preoperative therapeutic ERCP was successful in all 14 patients (100%). Diagnostic ERCP was attempted in 61 patients and successful in 59 (97%). Choledocholithiasis was identified in 25 patients (41%). Successful extraction was accomplished in 23 patients (92%). Transcystic common bile duct exploration was used effectively in the patients with an unsuccessful ERCP. IOC was attempted in 50 patients and successful in 48 (96%). Choledocholithiasis was identified in three (6%). A retained CBD stone was present in eight patients (1%). There was one level I CBD injury (0.122%). The use of IVC, selective ERCP, and selective IOC is a reasonable approach in the performance of laparoscopic cholecystectomy.  相似文献   
14.
Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor. In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until recently. Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor using a quick insulin assay. Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected (n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively, underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured. Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted using a quick insulin assay. This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006, Krakow, Poland.  相似文献   
15.
目的评价选择性臂丛神经根切断治疗上肢痉挛性脑瘫的远期疗效。方法对1997年3月-2002年1月间施行选择性臂丛神经根切断术治疗上肢痉挛性脑瘫的患者,进行随访并对远期功能进行评价,采用Lazareg肌张力分级标准评定临床效果。结果16例17侧获得随访,随访时间为5.0~9.7年,平均8.6年。手术方式为选择性臂丛神经根全根切断10侧,部分切断2侧,高选择性分束切断5侧;其中切断神经根为颈63次,颈816次。术后远期疗效优3例,有效5例,无效8例9侧。结论选择性臂丛神经根切断治疗上肢痉挛性脑瘫远期大多数疗效下降和无效,但术前严格选择痉挛较局限的病例、术中进行高选择性臂丛神经根分束切断、术后坚持长期康复训练仍然能获得较好的疗效。  相似文献   
16.
目的为提高手术安全性,在L2~S2选择性脊神经后根切断(SPR)手术时,对肛门括约肌进行肌电图(EMG)监测,并评价其作用。方法在SPR手术监测中,当对S2后根小束进行电刺激时,采用针状电极记录双侧肛门括约肌的反应情况,有明显反应的后根小束予以保留。手术后随访患者踝痉挛改善情况和括约肌功能变化情况。结果所有患者手术后踝痉挛均有明显改善,无大小便功能障碍发生。结论SPR手术包括S2后根时,术中括约肌EMG监测对保证疗效,保护括约肌功能,提高手术安全,具有重要意义。  相似文献   
17.
曹卫东 《基层医学论坛》2007,11(10):865-866
我院现有后勤职工72名,占全院总人数的7%,其中党员12名。党员占后勤职工16%。笔者自担任后勤分管领导以来,一直重视狠抓后勤党员队伍建设,充分发挥其先锋模范作用,增强带头示范效应。提升后勤队伍凝聚力,使得后勤队伍的工作积极性得到较大提高,后勤部门的服务效率、保障功能和职工满意度都取得新的突破。[第一段]  相似文献   
18.
Latent inhibition (LI) of a conditioned emotional response (CER) has been proposed as a quantitative measure of selective attention. We have assessed the parallels of the pharmacology of LI in rats with the clinical pharmacology of schizophrenia. Drug and vehicle treated rats were divided into groups and preexposed 20 times to cage illumination as a CS, or not preexposed. All groups were conditioned with 2 CS-footshock pairings. The following day CER, as measured by interruption of drinking in response to CS presentation, was recorded. LI was observed as a decreased CER in preexposed relative to non-preexposed animals. LI was enhanced by haloperidol 0.3 mg/kg after 7 or 14 daily treatments, but not after a single acute dose. Haloperidol doses of 0.3 and 0.03 mg/kg enhanced LI, while doses of 0.003 and 3.0 mg/kg had no effect. Haloperidol enhancement of LI was unaffected by the coadministration of the anticholinergic agent trihexyphenidyl. Enhancement of LI is exhibited by the antipsychotic drugs fluphenazine, chlorpromazine, thiothixene, thioridazine, mesoridazine, and metoclopramide but not clozapine. The non-antipsychotic drugs pentobarbital, imipramine, chlordiazepoxide, trihexyphenidyl, and promethazine failed to enhance LI. LI exhibits striking parallels to the clinical pharmacology of schizophrenia.Preliminary data were presented in part at the Society for Neuroscience Annual Meeting, Phoenix, AZ, 1989  相似文献   
19.
The behavioural effects of selective -, - and -opioid agonists in 5-, 10- and 20-day-old rats were investigated by observational analysis. The predominant response to -agonists was behavioural depression. High doses (10 mg/kg IP) of morphine and DAGO (d-Ala2, NMe-Phe4, Glyol5-enkephalin) produced overt sedation in all the age groups and also induced catalepsy which was particularly apparent in the 5- and 10-day-old animals. These compounds did not produce any signs of behavioural activation in the neonatal rats. In contrast, rat pups treated with the -agonists U50,488H and PD 117,302 (1,10 mg/kg IP) exhibited marked hyperactivity with increases in wall-climbing and locomotion. Sedative effects of the highest dose of the -agonists began to emerge, however, as the animals grew older, resulting in significant decreases in behaviours such as gnawing and grooming at 20 days of age. The -agonist (+)-tifluadom (0.1–10 mg/kg), but not its corresponding (-)-isomer, produced an increase in activity in 5-day-old rats, thus extending the observations made with U50,488H and PD 117,302 and establishing the stereoselective nature of the response. The involvement of -receptors in opioid-induced hyperactivity was further substantiated by using a variety of opioid antagonists. In this context, the increase in activity induced by U50,488H (10 mg/kg) in 5-day-old neonates was attenuated by naltrexone (1 mg/kg IP) but not by larger doses (10 mg/kg) of either M8008 (which has low affinity for -receptors) or the selective -receptor antagonist ICI 174,864. Finally, DPDPE (d-Pen2, d-Pen5-enkephalin) which acts selectively at -opioid receptors, did not exert any behavioural effects in either the 5-, 10- or 20-day-old rat pups at doses of up to 10 mg/kg. These results demonstrate behavioural effects of - and -but not -agonists in neonatal rats. There is a clear differentiation between - and -receptor effects and both - and -mediated behaviours show dissimilarities from the adult profile.  相似文献   
20.
In the first experiment, 48 subjects carried out a visual spatial attention task. Stimuli were presented at the vertical meridian, either above or below a fixation dot, and the subjects were instructed to attend to one of these stimulus positions and ignore the other position. In three different conditions, the distances between stimulus positions and fixation were 0.5°, 0.9°, and 1.3°. Subjects searched for the presence of prememorized target letters at the attended location: memory load was one or four items in different conditions. The P1/N1 enhancement typically found on the horizontal dimension was not observed on the vertical dimension. Instead, a positive shift of the attended compared with the unattended stimuli was found, which was most prominent at anterior electrodes. This positivity showed effects of the distance manipulation. The N2b-P3a effect of attention and the effect of memory load (search negativity) normally present in this kind of selective search task were also found. Reaction times were faster when attention was directed above fixation than when it was directed below fixation. The event-related potential data suggested that this difference could be attributed to a more efficient neglecting of irrelevant stimuli presented below fixation. In Experiment 2, we examined whether the absence of the P1/N1 enhancement as the result of spatial attention in Experiment 1 could be attributed to (a) the presentation of stimuli along the vertical meridian instead of along the horizontal meridian, (b) the use of midline electrodes instead of lateralized electrodes, and (c) the relatively small spatial separation between the relevant and irrelevant stimuli. Twelve subjects searched for the presence of a single target letter at an attended position in three different conditions. In two of the conditions the letters were presented to the left or right of fixation. The distance between fixation and the stimulus positions was 1.3° in one of these conditions and 3° in the other condition. In the third condition, the stimuli were presented at 3° above or below fixation. In all three conditions effects similar to those in Experiment 1 were observed. In addition, in all three conditions an enhancement of the P1 and N1 components was found at two lateral occipitotemporal electrodes.  相似文献   
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