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91.
92.
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV) in communicating hydrocephalus. Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve after ETV. Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the CSF sufficiently.  相似文献   
93.
Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.  相似文献   
94.
The regional distribution of the phenylalanine-sensitive ATP-sulphurylase in fetal calf brain coincides with demyelinated lesions observed in the central nervous systems of untreated PKU patients. This would be expected if this species of ATP-sulphurylase played a role in the pathogenesis of brain dysfunction in the untreated or poorly controlled phenylketonuria patient.  相似文献   
95.

Background  

Reports on childhood cancer survivors estimated cumulative probability of developing secondary neoplasms vary from 3,3% to 25% at 25 years from diagnosis, and the risk of developing another cancer to several times greater than in the general population.  相似文献   
96.
Abstract Background and study aims: The advent of endoscopic techniques in the last decades has produced a change in the approach of the oesophageal leiomyoma. The aim of the study is to explain our experience in the laparoscopic surgery of the oesophageal leiomyoma. Materials and methods: We realised a retrospective study of the oesophageal leiomyoma operated on in our centre by the endoscopic approach between 2001 and 2004. There were two females and two males. All were symptomatic and pyrosis was the most frequent symptom. The preoperative study was an oral endoscopy and barium swallow. In all the cases enucleation was performed, two by thoracoscopy and two by laparoscopy approach. Results: The mean operating time was 230 min. No deaths or intraoperative complications occurred and there were no cases of conversion to open surgery either. The mean postoperative hospital stay was 3.25 days (range 2–4 days). There was no case of recurrence. Conclusions: The enucleation is an easier procedure and constitutes the therapy of choice of the oesophageal leiomyoma. We think that muscle borders should be closed after enucleation and that biopsy is not indicated preoperatively.  相似文献   
97.
Rapid voltammetric procedures for the determination of water-soluble vitamins C, B1, and B2, fat-soluble vitamin E (α-tocopherol acetate), and quercetin in bioactive food additives have been developed. The systematic error (i.e., correctness) of the proposed procedures was evaluated using certified reference materials and the additive recovery tests, which gave the following limiting metrological characteristics: relative error, 25 %; reproducibility, 28 %; convergence, 22 %. The full analysis time (with sample preparation) did not exceed 2 hours. Voltammetric determinations under optimum conditions can be performed in the automated regime controlled by a computer according to the specially developed software.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 3, pp. 54 – 56, March, 2005.  相似文献   
98.
The influence of chronic administration of a dry cleared extract of Glycyrrhiza glabra (DCEG) containing flavonoids on the behavioral status and learning of intact and ovariectomized adult female rats has been studied. The DCEG preparation was administered in low (0.5 mg/kg, i.p.) and high (5.0 mg/kg, i.p.) daily doses over a period of 14 days and the results were evaluated on the passive avoidance situation model and in the open field test. It was established that the chronic administration of DCEG in both low and high doses produced correction of the passive avoidance performance in ovariectomized female rats. The administration of DCEG in a low dose also positively influenced the structure of purposeful behavior of females with deficiency of estrogens. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 27 – 29, August, 2005.  相似文献   
99.
The kinetics of alkaline hydrolysis of N-(5-nitro-2-thiazolyl)-2-thiophenylcarboxamide (tenonitrozole or atrican) has been studied by photometric and polarographic techniques, and the thermodynamic parameters in the intermediate state of this process were determined. A mechanism explaining the nitric oxide (NO) production during the hydrolytic decomposition of tenonitrozole is proposed. It is suggested that the antiprotozoal and antimicrobial activity of this drug under anaerobic conditions is related to the formation of nitro radical anions and NO. Under aerobic and microaerophilic conditions, the hydrolysis of tenonitrozole may lead to the formation of a peroxynitrite anion, which is a strong cytotoxic agent. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 6, pp. 15 – 18, June, 2005.  相似文献   
100.
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