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791.
Furosemide inhibits regenerative cortical spreading depression in anaesthetized cats 总被引:2,自引:0,他引:2
SJ Read MI Smith CD Benham AJ Hunter AA Parsons 《Cephalalgia : an international journal of headache》1997,17(8):826-832
Ionic perturbations occur during cortical spreading depression (SD), a phenomenon implicated in migraine pathophysiology. We studied the effect of 0.2,2 and 20 mg kg−1 iv ( n =4) furosemide on cortical direct current (d.c.) potential, cerebrovascular laser Doppler flux (rCBFLDF ), artery diameter and NO concentration in the parietal cortex of the anaesthetized cat during repetitive SD. In vehicle treated animals ( n =4), SD activity was sustained for 50 1.8 min. However, duration of SD activity was significantly reduced when compared to vehicle to 39 6.6 ( n =4), 3.1 8.3 ( n =4) and 27.3 11.3 min ( n =4), at 0.2, 2 and 20 mg kg−1 iv furosemide respectively. It is hypothesized that the mechanism of inhibition of SD d.c. activity by furosemide may be through alterations in cortica ion buffering capacity or inhibition of cell swelling in neurones or glia. These mechanisms may represent potential novel drug targets in future migraine therapy. 相似文献
792.
Recombinant immunoblot assay reaction patterns and hepatitis C virus RNA in blood donors and non-A, non-B hepatitis patients 总被引:5,自引:0,他引:5
D Bresters ; HL Zaaijer ; HT Cuypers ; HW Reesink ; IN Winkel ; PJ van Exel-Oehlers; AA van Drimmelen; PL Jansen ; CL van der Poel; PN Lelie 《Transfusion》1993,33(8):634-638
To establish the value of the second-generation recombinant immunoblot assay (RIBA-2) and cDNA polymerase chain reaction (cDNA PCR) for confirmation of hepatitis C virus (HCV) infection, anti-HCV reaction patterns and the presence of HCV RNA were examined in 610 blood donors and 255 non-A, non-B hepatitis patients who were positive or indeterminate in RIBA-2. Of RIBA-2-positive donors (n = 191) and patients (n = 224), 75.4 and 89.7 percent, respectively, were HCV RNA positive. The most frequently observed anti-HCV recognition patterns in HCV RNA-positive donors and patients were c22, c33c, and c100 and/or 5- 1-1 (67.3%, 57.7%) and c22, c33c (24.8%, 29.3%). Among subjects with a RIBA-2-indeterminate result, HCV RNA was detected more often in patients (n = 31) than in donors (n = 419): 67.7 and 2.1 percent, respectively. In viremic persons with single-band reactivity in RIBA-2, this reactivity was always directed against either c22 or c33c. HCV RNA was detected by cDNA PCR in none of 162 persons with only anti-c100 and/or anti-5-1-1 reactivity. Therefore, RIBA-2 reactivity against c100 in combination with 5-1-1 should not be considered positive but indeterminate. In RIBA-2-indeterminate persons, HCV RNA detection is necessary for reliable confirmation of HCV infection. 相似文献
793.
A Zhang SY Chaw AA Talacko WJ Besly NW Savage PA Monsour 《Australian dental journal》2016,61(3):381-385
The calcifying epithelial odontogenic tumour (CEOT), or Pindborg tumour, is a rare, benign odontogenic tumour. CEOT is usually asymptomatic and an incidental radiological finding, often presenting as a mandibular radiolucency with flecks of calcific material. We report an unusual case of CEOT in the left posterior maxilla of a 46‐year‐old male that was associated with an unerupted tooth. The tumour in this case caused non‐specific sinus symptoms and appeared radiographically similar to an odontoma or ossifying fibroma due to its dense calcific contents. Diagnosis was confirmed histologically following surgical removal of the lesion, which showed classic CEOT histomorphology. We report this case to highlight the unusual clinico‐radiologic presentation and illustrate the diagnostic difficulties that can occur with radiolucent and/or radiopaque lesions in the jaws. 相似文献
794.
AA Polydorou EV Pantiora A Vezakis P-T Arkoumanis CJ Psichogios EA Kontis Georgios P Fragulidis G Polymeneas 《Hellēnikē cheirourgikē. Acta chirurgica Hellenica》2018,90(1):9-15
Aim-Background
Infected pancreatic necrosis (IPN) develops in approximately one third of patients with necrotizing pancreatitis (NP). In the past, open necrosectomy (ON) was the standard treatment for this condition, but it carried significant morbidity and mortality. Currently, minimally invasive procedures (MIPs) have been established for the management of IPN, decreasing the risk of complications compared with ON.Methods
A prospective study was made of patients with IPN treated by a MIP for necrosectomy via a percutaneous drainage catheter, followed by video-assisted retroperitoneal debridement (VARD).Results
Between 2013 and 2016, 3 consecutive patients, with a mean age of 58 years, underwent a MIP for the management of IPN. All 3 patients had left lateral retroperitoneal pockets of necrosis, and the first-line procedure consisted of placement of a pigtail catheter. The drain tract was subsequently used to carry out VARD. None of the patients presented major postoperative complications or required re-intervention.Conclusion
The management of IPN has shifted away from ON, which was associated with high morbidity, towards less invasive techniques. MIPs should be used initially as the surgical treatment of choice in most cases. When this is not feasible, or when the MIP is not successful, ON should be implemented.795.
Sandip Pravin Patel MD Edward Mayerson MS Young Kwang Chae MD MPH MBA Jonathan Strosberg MD Jue Wang MD Bhavana Konda MD MPH Jourdain Hayward BS Christine M. McLeod AA Helen X. Chen MD Elad Sharon MD MPH Megan Othus PhD Christopher W. Ryan MD Melissa Plets MS Charles D. Blanke MD Razelle Kurzrock MD 《Cancer》2021,127(17):3194-3201
796.
The incidence of hepatocellular carcinoma is increasing worldwide as well as the associated risk factors, some of which include exposure to aflatoxin B1, Hepatitis B (HBV) virus and hepatitis C (HCV) virus. Mutation of tumour suppressor gene p53 at codon 249ser at exon 7 has been found to contribute significantly to replication of damaged DNA and subsequent tumour progression. The x gene of HBV (HBx) is the most common open reading frame integrated into the host genome in hepatocellular carcinoma and the integrated HBx is frequently mutated in hepatocellular carcinoma. Mutant HBx proteins still retain their ability to bind to p53 thereby attenuating DNA repair and p53-mediated apoptosis. 相似文献
797.
798.
799.
This paper describes the surgical method and instruments for placing and anchoring the Apex polyester fibre anterior cruciate ligament (ACL) reconstruction. It then reviews the early clinical findings and describes recent developments. At the time of review, 172 Apex replacements had been implanted in the UK in arthroscopically proven chronic ACL-deficient knees. These had been inserted at eight centres since 1987, and follow up was by a single observer assessing patients by questionnaire, clinical examination, stress X-ray and KT 1000 arthrometer. Patients less than 12 months from surgery were excluded, leaving 95 with a mean follow up of 27 months (range 13 to 66 months) on whom results are based. Assessment showed improved stability after operation and the Apex implant appears to provide a reliable method of stabilizing the ACL deficient knee within the confines of this short-term review. The authors feel that further trials are justified. 相似文献
800.
HZ Abdel‐Hafez E‐EM Mohamed AA Abd‐Elghany 《Journal of the European Academy of Dermatology and Venereology》2010,24(6):704-708
Background Oxidative stress (OS) results from an imbalance between free radical generating and scavenging systems. The end product of lipid peroxidation, malondialdehyde (MDA) serves as a marker of cellular damage. Superoxide dismutase (SOD) traps free radicals and acts as a free radical scavenging system. Objective To study OS indices in paucibacillary (PB) and multibacillary (MB) leprosy in tissues and blood. Materials and methods The study group comprised untreated PB patients (n = 14), untreated MB patients (n = 18) and normal human volunteers (n = 20). SOD activity, MDA level and MDA/SOD ratio were estimated in both blood and tissue. Results Compared with controls, SOD activity in tissues decreased significantly in both PB and MB patients, while SOD activity in erythrocytes decreased significantly only in MB. In addition, MDA levels increased significantly in tissues of both PB and MB patients. Moreover, the mean level of MDA in plasma of MB patients was significantly higher, whereas there was no significant difference in that of PB patients. This study showed significant increase in OS index (MDA/SOD ratio) in tissue of PB and MB patients and in blood of MB patients only, whereas there was no significant difference in OS index in blood of PB patients compared with that in the controls. Conclusion Oxidative stress was observed in both tissues and blood of MB patients and in tissues of PB patients, denoting its crucial involvement in the pathogenesis of leprosy. This can constitute an important tool in prognosis, treatment and control of leprosy. 相似文献