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991.
视觉电生理联合应用对眼外伤视觉功能的评价   总被引:11,自引:1,他引:10  
联合使用视觉电生理检查法评估外伤眼的视功能。方法单纯眼外伤30例按受伤程度分3组,健康对侧眼为对照组,比较各组VEPP100波潜伏值,30Hz红闪炮光ERG的振幅和暗适应ERGa、b波振幅的平均值。结论联合应用视觉电生理检测法是评价眼外伤视功能的可靠依据。  相似文献   
992.
本文回顾分析26 例 (26 眼) 5~14 岁儿童角膜穿通伤合并外伤性白内障植入后房型人工晶体的临床结果。对麻醉、人工晶体植入、后囊纤维膜样混浊进行了分析讨论。提示 8 周岁以上儿童常能在眼局部麻醉下顺利地完成手术。认为对儿童角膜穿通伤合并外伤性白内障植入人工晶体, 应视眼部伤情及术中情况, 权衡利弊, 区别选择Ⅰ期或Ⅱ期植入。作者观察到, 这类联合手术的后囊纤维膜样改变, 在术后一至二周即在不同程度上有所表现。  相似文献   
993.
In this study the effect of nitric oxide (NO) synthesis inhibition on ethanol-induced gastric damage was evaluated in bile duct-ligated, sham-operated and unoperated rats. The animals were injected intraperitoneally with saline, -arginine (200 mg/kg) or NG-nitro- -arginine methylester ( -NAME) in doses of 5, 15 and 30 mg/kg, 30 min before ethanol administration. The animals were killed 1 h after ethanol administration and their stomachs were removed for measurement of gastric mucosal damage. The results showed that -NAME significantly enhanced the development of gastric mucosal lesions in sham-operated and unoperated rats, while in bile duct-ligated animals, -NAME decreased and -arginine enhanced the potentiation of ethanol-induced gastric mucosal damage. The plasma level of nitrite and nitrate was also measured and was significantly higher in bile duct-ligated rats than in control groups. The results suggest that inhibition of NO synthase with -NAME has different effects on ethanol-induced gastric damage in cholestatic groups and in normal rats and that these effects can be explained by overproduction of NO in bile duct-ligated animals.  相似文献   
994.
Neuroleptic malignant syndrome is an idiosyncratic reaction associated with the use of neuroleptic drugs. We report a case of this rare syndrome in a head injury patient associated with some unusual features: rhabdomyolysis with a high level of creatine kinase, the development of acute renal failure, the early use of continuous venovenous haemofiltration in treatment and rigidity that was refractory to conventional treatment with dantrolene and bromocriptine. The diagnosis in patients with multiple injuries must be based on a high index of suspicion.  相似文献   
995.
Acid inhibition increases gastric mucosal susceptibility to damage by luminal acid. This might be due to reduced metabolic CO2 and bicarbonate whereas, during normal acid, secretion cytoprotective CO2/HCO3- production parallels acid production. Metabolic activity and mucosal damage caused by luminal acid perfusion was determined in anin vitro mouse stomach, with and without acid inhibition, and at 0%, 1%, or 5% serosal CO2 supply. Without acid inhibition there was no mucosal damage at any level of serosal CO2/HCO3- supply. Acid inhibition reduced metabolic CO2 production by 29% (P<0.004) and resulted in microscopic damage to 55% of the mucosal area and perforation in four of five stomachs (P<0.05). Although, 1% CO2 supply completely replaced the reduction in metabolic CO2, it did not protect against mucosal damage. Overreplacement by 5% serosal CO2/HCO3- was required to prevent damage. There was no correlation between luminal CO2/HCO3- output and mucosal damage. The protection by endogenous or exogenous CO2/HCO3- appears to act intracellularly rather than by intragastric or intercellular neutralization.This study was supported by Swiss National Foundation grants 32-26369.89 and 32-33626.92. The morphometry equipment was supported by a grant from the Osterreichische Nationalbank.  相似文献   
996.
Summary The purpose of this study was to compare the effect of hyper-ventilation and indomethacin on cerebral circulation, metabolism and pressures in patients with acute severe head injury in order to see if indomethacin may act supplementary to hyperventilation. Fourteen severely head injured patients entered the study. Intracranial pressure (ICP), mean arterial blood pressure (MABP) and cerebral perfusion pressure (CPP) were monitored continuously. Within the first four days after the trauma the CO2 and indomethacin vasoreactivities were studied by measurements of cerebral blood flow (CBF) (Cerebrograph 10a, intravenous133Xe technique) and arterio-venous difference of oxygen (AVdO2). Ischaemia was evaluated from changes in CBF, saturation of oxygen in the jugular bulb (SvjO2), lactate and lactate/oxygen index (LOI). Data are presented as medians and ranges, results are significant unless otherwise indicated. Before intervention ICP was well controlled (14.8 (9–24) mmHg) and basic CBF level was 39.1 (21.6–75.0) ml/100 g/min). The arterio-venous oxygen differences were generally decreased (AVdO2 = 4.3 (1.8–8.1) ml/100 ml) indicating moderate luxury perfusion. Levels of CMRO2 were decreased (1.54 (0.7–3.2) ml/100 g/min) as well.Duringhyperventilation (APaCO2 = 0.88 (0.62–1.55) kPa) CBF decreased with 11.8 (–33.4–29.7) %/kPa and ICP decreased with 3.8 (0–10) mmHg. AVdO2 increased 34.0 (4.0–139.2) %/kPa, MABP was unchanged, CMRO2 and CPP increased (CPP = 3.9 (–10–20) mmHg). AVD (lactate) and LOI were unchanged. No correlations between CBF responses to hypocapnia and outcomes were observed.An i.v. bolus dose ofindomethacin (30 mg) decreased CBF 14.7 (–16.7–57.4) % and ICP decreased 4.3 (–1–17) mmHg. AVdO2 increased 27.8 (–40.0–66.7)%, MABP (MABP = 4.9 (–2–21) mmHg) and CPP (CPP = 8.7 (3–29) mmHg) increased while CMRO2 was unchanged. No changes in AVd (lactate) and LOI indicating cerebral ischaemia were found.Compared to hyperventilation (changes per 1 kPa, at PaCO2 level = 4.05 kPa) the changes in MABP, CPP and CBF were significantly greater after indomethacin, while the changes in AVdO2, ICP, SvjO2, and LOI were of the same order of magnitude.Nocorrelation between relative reactivities to indomethacin and CO2, evaluated from changes in CBF and AVdO2, or between the decrease in ICP after the two procedures were found. Thus, some patients reacted to indomethacin but not to hyperventilation, and vice versa.These results suggest that indomethacin and hyperventilation might act independently, or in a complementary fashion in the treatment of patients with severe head injury.  相似文献   
997.
Summary The choice of the surgical approach and operative technique for the management of cerebrospinal fluid (CSF) fistulas of the anterior cranial fossa are still a controversially discussed topic. Although extracranial approaches through the paranasal sinuses are becoming increasingly more popular among otolaryngologists and maxillo-facial surgeons, most neurosurgeons traditionally prefer the intracranial repair of CSF fistulas by a craniotomy.We present an approach through the frontal sinus for the repair of dural defects behind the posterior wall of the frontal sinus and at the floor of the anterior cranial fossa. The operative procedure comprises the following main steps: 1) exposure of the anterior wall of the frontal sinus by a bicoronal incision; 2) excision of the anterior wall without frontal burr holes; 3) bilateral removal of the posterior wall of the fronal sinus; 4) extradural inspection of the dura behind the frontal sinus and above the cribriform plate, ethmoidal roof, and orbital roof bilaterally; 5) closure of dural tears by direct suture and a periosteal graft; 6) reinsertion of the anterior wall of the frontal sinus and fixation with titanium micro plates.Twenty-five patients operated upon using this technique are described. The aetiology of the frontobasal lesion was traumatic in 23, and an ethmoid carcinoma in two. In all patients, the dural fistulas were successfully repaired during the initial procedure. One patient died from sudden circulatory arrest after an uneventful postoperative course of nine days. Otherwise, there were no postoperative complications.This technique affords atraumatic extradural inspection and repair of dural fistulas bilaterally behind the frontal sinus, and above the cribriform plate and the ethmoidal and orbital roofs with none or minimal brain retraction. It therefore allows early repair of CSF fistulas also in patients with severe brain injury. Although we consider the extradural closure of fistulas the method of choice, this approach also allows for a combined extradural-intradural procedure, thus enabling the surgeon to treat associated intradural pathologies, such as traumatic lesions or tumours of the frontal cranial base.  相似文献   
998.
Summary Ketamine was supposed to be contra-indicated in head injured patients although it possesses numerous advantages over other commonly used analgosedative drugs. Referring to these potential advantages and the lack of definitive data about its effect upon ICP, CPP or neurological development, we conducted a prospective study in which moderate or severely head injured patients (n=35) were prospectively allocated to receive treatment either with a combination of ketamine and midazolam or fentanyl and midazolam. The initial dose was 6.5 mg/kg/day midazolam, 65 mg/kg/day ketamine or 65 g/kg/day fentanyl and was later adjusted due to clinical requirements for a period of 3 to 14 days. Comparably high dosages of detamine have been found necessary (104 mg/kg/day).Four patients from the ketamine group (n=17) and 5 from the control group (n=18) were withdrawn during treatment due to persistent ICP above 25 mm Hg, countermeasured by barbiturate coma. Two more patients were withdrawn due to development of cardiovascular arrest (ketamine group) and multi organ failure. A comparison of the remaining patients revealed a lower requirement of catecholamines (significant on first day, p<0.05), an on average 8 mm Hg higher cerebral perfusion pressure and a 2 mm Hg higher intracranial pressure in the fentanyl group. Enterai food intake was better in the study group. The outcome was comparable in both groups with or without inclusion of withdrawn patients.  相似文献   
999.
The case of a young patient with left accessory nerve paralysis is reported. He had slight tilting of the head to the right side, developed over a period of about 6 months. On neurological examination hypotrophy of the left sternocleidomastoid and trapezius muscles was observed. MRI and MR-angiography imaged the presence of a neurovascular compression between the medulla oblungata, at the level of the nerve entry zone, and a vessel loop of an elongated left vertebral artery. In spite of the absence of a surgical demonstration it is our opinion that the neurovascular conflict is the cause of the accessory nerve palsy.  相似文献   
1000.
Radiographic studies of the ventricles in syringomyelia   总被引:3,自引:0,他引:3  
Summary Radiographic investigations of 171 patients with communicating syringomyelia have been reviewed. Hydrocephalus was found in onethird of the cases and has occasionally progressed after operation on the posterior fossa, sometimes with accompanying clinical deterioration. The outlets of the fourth ventricle were usually abnormal; tonsillar descent, arachnoiditis and both together were seen. Arachnoiditis correlated strongly with a history of difficult birth. The foramen of Magendie was sometimes patent and sometimes blocked. There was no consistent level of occlusion corresponding to a persistent roof of the fourth ventricle. The cisterna magna was usually small or obliterated but some examples of large cisterns or subarachnoid pouches were found. Radiological demonstration of a communication from the fourth ventricle to the syrinx occurred in only seven patients by positive contrast material and not by air. It is suggested that a sizable communication is rare at the time when patients seek treatment.  相似文献   
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