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81.
Andaluz N  Tew JM 《Neurosurgery》2003,53(2):432-5; discussion 435
OBJECTIVE AND IMPORTANCE: We present a rare case of an intradural aneurysm that arose from the posterior genu of the cavernous carotid artery and was diagnosed via angiography as originating from the internal carotid artery (ICA) at the level of the posterior communicating artery. Our review of the English-language literature found no other case of an intradural aneurysm that originated at the posterior genu of the cavernous ICA. CLINICAL PRESENTATION: A 65-year-old woman presented with increasingly severe left retro-orbital headaches. Her family history included aneurysmal subarachnoid hemorrhage. Angiography revealed an 11-mm aneurysm, which was interpreted as arising from the left ICA at the level of the posterior communicating artery. INTERVENTION: During a left pterional craniotomy, an aneurysm was identified underneath the oculomotor nerve; its neck seemed to arise from the posterior communicating artery segment. Despite clipping of the aneurysm attachment to the ICA and trapping of the posterior communicating segment, the aneurysm continued to fill. Further dissection revealed that the aneurysm's neck originated from the cavernous ICA. Placement of fenestrated clips around the oculomotor nerve successfully occluded the intradural portion of the aneurysm, as documented by an intraoperative angiogram. CONCLUSION: We discuss this unique case to draw attention to the importance of the interpretation and adequacy of preoperative angiography, and we review pertinent vascular anatomy.  相似文献   
82.
Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobiliary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases.  相似文献   
83.
High dose intravenous(i.v.) ascorbic acid (AA) has been used as therapy for infectious disease from bacterial and viral origin and adjuvant therapy for cancer. In this publication we describe a clinical protocol that has been developed over the past twenty years utilizing high dose i.v. AA as therapy for cancer. This includes principles of treatment, rationale, baseline workup, infusion protocol, precautions and side effects.  相似文献   
84.
The macrothrombocytopenias make up a heterogeneous group of disease involving thrombocytopenia and giant platelets; other clinical or laboratory findings, such as hereditary nephritis, sensorineural hearing loss, leukocyte inclusions, and cataracts, may also be present. The tendency to bleeding is highly variable and is due to decreased expression of the GP1b-V-IX complex on the surface of platelets, leading to altered platelet-vessel wall and platelet-platelet interactions. The 5 autosomal dominant giant-platelet disorders that are associated with macrothrombocytopenia are May-Hegglin anormaly, Epstein, Fechtner, and Sebastian syndromes, and Alport-like syndrome with macrothrombocytopenia. The mutation responsible is in gene 9 (MYH9) coding for the nonmuscle myosin heavy chain IIA that has been identified in the long arm of chromosome 22 (22q12.3-q13.2). The most recently described macrothrombocytopenia is Sebastian syndrome, consisting of thrombocytopenia with giant platelets and leukocyte inclusions. We report the case of a woman with Sebastian syndrome scheduled for abdominoperineal resection for rectal carcinoma. Preoperative studies revealed isolated thrombocytopenia (35,000 platelets/microL) and a mean platelet volumen of 13 fL. Preoperative prophylactic platelet transfusion was carried out with no adverse events. After a postoperative transfusion of packed red cells, needed because of abundant bleeding, clinical course continued to be satisfactory. The anesthetic implications of this syndrome are not well known because few cases have been reported in the literature, and none was found that describes anesthetic management. Nevertheless, thrombocytopenia and the tendency to bleeding present challenges to the anesthesiologist.  相似文献   
85.
OBJECTIVE: This study analyzed the frequency of CYP2C9 variant alleles and evaluated the impact of CYP2C9 genotype on diclofenac metabolism in a Spanish population. METHODS: Diclofenac hydroxylation capacity was studied in a population of 102 healthy volunteers. After a single oral dose of 50 mg diclofenac the 0- to 8-h urinary concentrations of diclofenac and its main metabolites, 4'-hydroxy (OH), 3'-OH and 5-OH diclofenac were analyzed by high-performance liquid chromatography. CYP2C9 genotyping for the variant alleles CYP2C9*2 and *3 was carried out with PCR-RFLP. RESULTS: The frequencies of CYP2C9*1, *2, and *3 alleles were 0.74 (95%CI: 0.68-0.80), 0.16 (95%CI: 0.11-0.21) and 0.10 (95%CI: 0.06-0.15), respectively, among the 102 Spaniards studied. The diclofenac/4'-OH diclofenac urinary ratio, but not the diclofenac/3'-OH diclofenac and diclofenac/5-OH diclofenac ratios, was related to CYP2C9 genotype. The diclofenac/4'-OH ratio was significantly higher among subjects with CYP2C9*1/*3 (0.83+/-0.4, n=14, 95% CI for the difference: 0.02-0.4) and CYP2C9*2/*3 (1.10+/-0.5, n=4, 95% CI for the difference: 0.16-0.8) genotypes compared to CYP2C9*1/*1 (0.62+/-0.3, n=59) and approximately threefold higher (1.8) in the only subject homozygous for CYP2C9*3 variant. CONCLUSIONS: The frequencies of CYP2C9*1, *2, and *3 alleles in the Spanish population reported here were similar to those found in the previously studied white European populations, and different of the previously reported in another Spanish population. CYP2C9*3 allele seems to influence the 4'-hydroxylation of diclofenac, although there is a large overlapping in the urinary metabolic ratio between the genotype groups studied  相似文献   
86.
87.
Herpesviruses, in particular Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpesvirus 6 (HHV-6), have, for the past two decades, come under considerable scrutiny as aetiological agents of chronic fatigue syndrome (CFS). However, virological findings of herpesviruses in CFS have not been consistent between different studies, and the unusual patterns of serological responses to EBV, CMV and HHV-6 have not been specific for CFS, being observed also in asymptomatic individuals. In addition, patients with symptomatology suggestive of CFS do not appear to have an increased frequency of these herpesviruses, as detected by culture or polymerase chain reaction, compared with controls, which argues against an ongoing active herpetic infection. Studies have also shown that the presumable elevation of antibody titres to EBV, CMV or HHV-6 in CFS are not observed only with these viruses, but also with other organisms such as herpes simplex virus and measles.  相似文献   
88.

Background  

Iatrogenic perforation due to colonoscopy is the most serious complication of this procedure. Usually, resolution of this event requires segmental resection. The laparoscopic approach could be an option to minimize the outcome of this complication. The aim of the present study was to assess the effectiveness of the laparoscopic approach in treating colonic perforations due to colonoscopy.  相似文献   
89.
Root end cavity preparation techniques aim to create a clean and properly shaped cavity in a short time. Although the use of ultrasonics has been widely recommended, a laser can also be used. This study evaluated the time required and quality of retrograde cavity preparations using ultrasonics or ErCr:YSGG laser. Thirty single-rooted teeth were instrumented, root filled, submitted to apicectomies, and grouped. Root end cavities were prepared by using the following: group 1 (G1): CVD (6.1107-6) ultrasonic retrotips (CVD-Vale, São José dos Campos, Brazil); group 2 (G2): EMS (DT-060/Berutti) ultrasonic retrotips (EMS, LeSentier, Switzerland); and group 3 (G3): ErCr:YSGG (G6/Waterlase; Biolase Technology, San Clemente, CA) laser tips. The time taken to complete the preparation was recorded. Epoxy resin replicas of the root apices were examined under a scanning electron microscope. The parameters for evaluation were the presence of fractures, and the quality of the preparations. The Waterlase showed the highest mean time for preparation of the root end cavities (p < 0.05), and there was no significant difference between the CVD and EMS groups (p > 0.05). Fractures in the cavosurface angle occurred only in G2. G1 and G2 showed better scores for quality of preparation than G3 (p < 0.05). These results suggest that root end cavities should be prepared by ultrasonic tips.  相似文献   
90.
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