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1.

Background  

Outcomes collected in randomized clinical trials are observations of random variables that should be independent and identically distributed. However, in some trials, the patients are randomized more than once thus violating both of these assumptions. The probability of an event is not always the same when a patient is re-randomized; there is probably a non-zero covariance coming from observations on the same patient. This is of particular importance to the meta-analysts.  相似文献   
2.
Epilepsy is known as one of the most frequent neurological diseases, characterized by an enduring predisposition to generate epileptic seizures. Oxidative stress is believed to directly participate in pathways leading to neurodegeneration, which serves as the most important propagating factor, leading to the epileptic condition and cognitive decline. Moreover, there is also a growing body of evidence showing the disturbance of antioxidant system balance and consequently increased production of reactive species in patients with epilepsy. A meta-analysis, conducted in the present review confirms an association between epilepsy and increased lipid peroxidation. Furthermore, it was also shown that some of the antiepileptic drugs could potentially be responsible for additionally increased lipid peroxidation. Therefore, it is reasonable to propose that during the epileptic process neuroprotective treatment with antioxidants could lead to less sever structural damages, reduced epileptogenesis and milder cognitive deterioration. To evaluate this hypothesis studies investigating the neuroprotective therapeutic potential of various antioxidants in cells, animal seizure models and patients with epilepsy have been reviewed. Numerous beneficial effects of antioxidants on oxidative stress markers and in some cases also neuroprotective effects were observed in animal seizure models. However, despite these encouraging results, till now only a few antioxidants have been further applied to patients with epilepsy as an add-on therapy. Based on the several positive findings in animal models, a strong need for more carefully planned, randomized, double-blind, cross-over, placebo-controlled clinical trials for the evaluation of antioxidants efficacy in patients with epilepsy is warranted.  相似文献   
3.
Aneurysms of the inferior vena cava (IVC) are extremely rare. To the best of our knowledge, only 29 cases of IVC aneurysms are published in literature. We present a new case of surgically treated symptomatic saccular aneurysm of the infrarenal IVC and review previously published cases. Following resection of the aneurysm and the thrombosed infrarenal IVC, the patient fully recovered. Thrombosed IVC aneurysm may mimic a retroperitoneal tumour. In some cases, CT and MRI findings may be equivocal. Surgical treatment is indicated in all symptomatic and low-risk asymptomatic cases.  相似文献   
4.
In this study the role of oxidative stress in schizophrenia was investigated by evaluating the relationship of oxidative stress markers with neurochemistry, psychopathology, and extrapyramidal symptoms. Antioxidant activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and concentrations of malondialdehyde, protein carbonyls, nitrite, nitrate, glutathione, dopamine, noradrenaline, adrenaline, and serotonin were measured in 52 outpatients with DSM-IV diagnosis of schizophrenia treated with haloperidol decanoate. Psychopathology and extrapyramidal symptoms were assessed by positive and negative syndrome scale, global assessment of functioning, abnormal involuntary movement scale, Simpson Angus scale, and Barnes akathisia rating scale. Haloperidol dose was positively correlated with plasma protein carbonyls. Longer duration of illness was associated with decreased levels of glutathione peroxidase. Increased activity of superoxide dismutase was associated with increased levels of catalase, glutathione peroxidase, glutathione reductase and reduced glutathione, and decreased concentration of malondialdehyde, indicating joint action of various antioxidative systems. Increased levels of nitrite and noradrenaline were associated with decreased level of malondialdehyde. Akathisia was greater in patients with decreased catalase activity, indicating involvement of impaired antioxidant defense in developing extrapyramidal symptoms. These results confirm the hypothesis that oxidative stress is involved in pathophysiology of schizophrenia and severity of extrapyramidal symptoms.  相似文献   
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6.
The outcome of patient care can be dramatically improved by bringing rapid rescue and medical care to the mountain rescue scene and by rapid transport to a medical facility. The use of a helicopter for these purposes is common. It is necessary when it has clear advantages for victims in comparison with ground rescue and transport. Helicopters should work within the existing emergency medical system and must be staffed by appropriate mountain rescue and medically trained personnel. Activation time should be as short as possible. Activation of a helicopter for a mountain rescue should primarily include indication and assessment of flight and safety conditions. No other mediators or delaying factors should be permitted. The main safety criteria are appropriate mountain rescue and flight training, competence of air and ground crews, radio communication between the air and ground crews, and mission briefing before the rescue. Criteria for a helicopter used for mountain rescue are proper medical and rescue equipment, load capacity, adequate space, and others. There are two main groups of indications for use of a helicopter for mountain rescue: the patient's condition and the circumstances at the site of the accident. All persons responsible for the activation of the helicopter rescue operation should be aware of specific problems in the mountains or wilderness.  相似文献   
7.
OBJECTIVE: To evaluate relationships between bone mineral density and morphometric characteristics of squamous cells in cervical smears, serum estradiol levels, body weight, and body mass index. METHOD: Dual X-ray absorptiometry measurements were performed in 107 women who had recently undergone routine screening for cervical cancer. Serum estradiol levels were determined. Mean areas for squamous cells, squamous cell nuclei, and squamous cell cytoplasm were calculated, as well as the nucleus area to cytoplasm area ratio. RESULTS: The mean cell and cytoplasmic areas were significantly lower in women with lower T scores for femoral neck and lumbar spine (P<0.001). Mean T scores were significantly lower for the women with atrophic cells than for those with mature cells (P<0.001). A correlation between estradiol levels and T scores was found for the lumbar spine (P<0.05) but not for the femoral neck. Multiple linear regression analysis showed the cytoplasmic area to be the most significant predictor of T scores for the total hip, followed by BMI and age, and to be the only significant predictor of T scores for the total spine. CONCLUSION: Relationships were found between bone mineral density and both the total cell and cytoplasmic areas of squamous cells obtained from cervical smears.  相似文献   
8.
Takac I  Gorisek B 《Tumori》1999,85(4):243-246
AIMS AND BACKGROUND: Our aim was to investigate whether loop excision is an acceptable alternative to traditional cold knife conization of the cervix. PATIENTS AND METHODS: 240 with cervical intraepithelial neoplasia (CIN) were randomly assigned to loop excision (n = 120) or cold knife conization (n = 120). Success and complication rates of both methods were analysed. RESULTS: 100% of cold knife conization and 98% of loop excision surgical specimens were positive for dysplasia. The rate of complete resection was 91% in the cold knife and 82% in the loop excision group, but histologic confirmation of residual CIN was obtained in only 2 (1.7%) women after cold knife conization and in 5 (4.2%) after loop excision. Loop excision cones were significantly shallower than those obtained by a cold knife. Secondary surgical procedures due to early hemorrhage were performed in 9 (7.5%) patients treated with cold knife conization and in 8 (6.7%) treated with loop excision. Elevated temperature postoperatively was observed in 16.4% of patients after cold knife conization and in 13.9% after loop excision. There were no other postoperative complications. CONCLUSIONS: The results suggest that cold knife conization and loop excision are comparable and equally effective diagnostic and therapeutic procedures for CIN.  相似文献   
9.
BACKGROUND: Studies have shown that 1-week triple therapy consisting of a proton pump inhibitor, amoxycillin and clarithromycin may cure Helicobacter pylori infection in the majority of patients. AIM: To establish whether pantoprazole plus amoxycillin in association with either azithromycin or clarithromycin is useful in curing H. pylori infection in patients with a duodenal ulcer. METHODS: One hundred and ten patients with active duodenal ulcers and H. pylori infection were treated with pantoprazole (days 1-7, 40 mg b.d.; days 8-28 40 mg o.d.) plus amoxycillin 1 g b.d. for the first 7 days. Patients were randomly assigned to receive either azithromycin 500 mg o.d. for the first 6 days (PAAz group; n=55) or clarithromycin 500 mg b.d. for the first 7 days of treatment (PAC group; n=55). H. pylori status was determined by urease test and histology before the treatment, and again 4 weeks after cessation of any medication. RESULTS: One hundred and three patients completed the study. H. pylori infection was eradicated in 78% (39/50) of patients in the PAAz group (ITT analysis: 71%, 95% CI: 61-83%) vs. 81% (43/53) of patients in the PAC group (ITT analysis: 78%, 95% CI: 69-90%) (N.S.). All ulcers had healed. CONCLUSION: Our study shows that 1-week triple therapy with pantoprazole, amoxycillin and either azithromycin or clarithromycin is not satisfactory (<80% ITT H. pylori eradication rate).  相似文献   
10.
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