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101.
Several investigators have estimated the intracranial volume (ICV) in the past which indirectly reflects the brain volume. Most of these studies have been made on the dry skulls using linear dimensions, packing methods or occasionally radiological methods. It is also reported that the etiology of cerebellar tonsillar herniation is closely related to the size of the foramen magnum (FM). In the present study the ICVs have been estimated in 28 dry skulls using filling water method and the surface area of FMs were measured planimetry method. The estimated mean ICV was 1,311 +/- 133 cm. Surface area of FM was 760 +/- 144 mm. Antero-posterior and lateral direct roentgenograms of the skulls were also taken and the width, height and length (WHL) of the skull were measured by means of the cephalometry on radiograms. The relationship between the ICV, WHL and surface area of FM were analyzed statistically. The ICV, WHL and surface area of FM was correlated well (r = 0.271, P < 0.005; r = 0.265, P < 0.005, respectively) and a regression formula was proposed. Our results showed that skulls with larger ICV and WHL have larger FM surface area. We also suggested a regression formula that could be used to predict the surface area of FM regarding to the ICV and WHL values. In the next step, we took roentgenograms of skulls and obtain ICV measuring the width, length and height of skulls by means of cephalometry and investigate the relation between the findings of cephalometry and surface area of FM. The cephalometry could apply on living subjects and, thereby, our findings could provide some data to evaluate the etiology of Arnold Chiari malformation and achondroplasia for living subjects.  相似文献   
102.
OBJECTIVE: To describe a case of hepatotoxicity associated with phenyramidol use that resolved after discontinuation of the drug. BACKGROUND: Phenyramidol is a moderately potent and relatively nontoxic analgesic with concomitant muscle-relaxant activity. A MEDLINE search in June 2003 revealed no reports associating hepatotoxicity with this agent. CASE SUMMARY: A 70-year-old man was investigated because of elevated liver function test values on routine biochemical screening. He had no clinical symptoms. Other etiologies of hepatitis were appropriately ruled out, and elevated enzymes were ascribed to phenyramidol treatment. DISCUSSION: This is the first case published in the English language literature describing probable hepatotoxicity, according to the Naranjo probability scale, resulting from use of phenyramidol. The mechanism of phenyramidol-induced liver damage is unknown. Several features, such as the absence of predictable dose-dependent toxicity of phenyramidol in previous studies and the absence of hypersensitivity manifestations in our patient, are suggestive of a metabolic type of idiosyncratic toxicity. CONCLUSIONS: Phenyramidol should be considered as a drug that possibly causes hepatotoxicity.  相似文献   
103.
Macroautophagy (autophagy) is a regulated catabolic pathway to degrade cellular organelles and macromolecules. The role of autophagy in cancer is complex and may differ depending on tumor type or context. Here we show that pancreatic cancers have a distinct dependence on autophagy. Pancreatic cancer primary tumors and cell lines show elevated autophagy under basal conditions. Genetic or pharmacologic inhibition of autophagy leads to increased reactive oxygen species, elevated DNA damage, and a metabolic defect leading to decreased mitochondrial oxidative phosphorylation. Together, these ultimately result in significant growth suppression of pancreatic cancer cells in vitro. Most importantly, inhibition of autophagy by genetic means or chloroquine treatment leads to robust tumor regression and prolonged survival in pancreatic cancer xenografts and genetic mouse models. These results suggest that, unlike in other cancers where autophagy inhibition may synergize with chemotherapy or targeted agents by preventing the up-regulation of autophagy as a reactive survival mechanism, autophagy is actually required for tumorigenic growth of pancreatic cancers de novo, and drugs that inactivate this process may have a unique clinical utility in treating pancreatic cancers and other malignancies with a similar dependence on autophagy. As chloroquine and its derivatives are potent inhibitors of autophagy and have been used safely in human patients for decades for a variety of purposes, these results are immediately translatable to the treatment of pancreatic cancer patients, and provide a much needed, novel vantage point of attack.  相似文献   
104.
Multiple spinal intramedullary cavernous angioma: case report   总被引:1,自引:0,他引:1  
Spinal cavernous angiomas frequently accompany to cranial cavernous angiomas. Multiple spinal cord cavernous angiomas are very rare and to authors knowledge, only one case has been described having multiple intramedullary cavernous angiomas without cranial involvement until now. In this report, we present a case with acute paraplegia who had thoracic and cervical intramedullary cavernous angiomas and normal cranial magnetic resonance imaging.  相似文献   
105.

Background

Cavernous malformations (CMs) of the central nervous system (CNS) are angiographically occult vascular lesions that affect approximately 0.5 % of the general population, and one quarter of all CMs occurs in children.

Methods

We retrospectively analyzed demographic, clinical, radiological, management, and follow-up data of 36 pediatric patients with CMs from a single institution.

Results

The mean age of the children at first presentation and at operation was 8.7 and 9.6 years, respectively. However, a bimodal age distribution was found with peak under 4 years and above 12 years. Seizure was the most common single presenting symptom (38.9 %), and 61.1 % of patients had at least one seizure before the admission. Focal neurological deficits (410.7 %), intracranial hypertension (27.8 %), and headache (2.8 %) were the other manifestations. Acute/subacute hemorrhage was evident at presentation in 63.9 %. The patients under 6 years of age were found to have significantly more giant cavernomas (69 vs 20 %; p?=?0.011), and more overt hemorrhages (81 vs 47 %; p?=?0.065) at diagnosis than those patients above 12 years. Surgery was performed in 31 patients (32 CMs), with 26 total and 6 incomplete resections. Mean follow-up duration was 6.9?±?4.1 years. Of all patients, 63.8 % had excellent and 30.5 % had good clinical outcomes, and also 90.9 % of the epileptic patients were seizure-free (Engel Class I) at the last follow-up.

Conclusions

Younger children tend to harbor larger CMs and present with hemorrhage more frequently than older ones. Microsurgical resection should be the treatment of choice in symptomatic and accessible CMs.  相似文献   
106.
We investigated the effects of the antioxidant alphae-tocopherol on early- and late-phase fracture healing in a rat model. Sixty male Sprague-Dawley rats were randomized into two groups. The right tibia of each rat was fractured manually under anaesthesia, and fracture sites fixed with intramedullary Kirschner wires. The alpha-tocopherol group received 20 mg/kg alpha-tocopherol intraperitoneally; the control group received intraperitoneal saline injections. Ten rats from each group were sacrificed on day 15, day 45 and day 60. In the alpha-tocopherol group, malondialdehyde concentrations, a measure of lipid peroxidation associated with oxygen free radicals, were significantly decreased on day 15 and day 45 compared with the control group, but had regained the 15-day value on day 60. On histopathological and radiological assessment, fracture healing on day 60 was significantly more advanced in the alpha-tocopherol group. We conclude that alpha-tocopherol has a positive effect on both early and late-phase fracture healing, and may be beneficial in clinical fracture  相似文献   
107.
108.
The aim of this prospective study was to evaluate the results and the complications at a tertiary referral center which frequently uses precutting techniques for biliary cannulation. Four hundred seventy patients with naive papilla for whom biliary intervention was planned were included in the study. If the selective cannulation was not achieved after a few trials, precutting sphincterotomy was performed. The results were evaluated for the frequency, success, and complication rates of precutting. Precutting was performed on 238 (50.6%; 117 male, 121 female; mean age, 58.5±16.2 years) of 470 patients. Total success rate of endoscopic retrograde cholangiopancreatography (ERCP) was 99.2% (236/238). The rate of complications in patients with versus without precutting was 7 (2.9%) versus 3 (1.3%) for pancreatitis, 2 (0.8%) versus 1 (0.4%) for perforation, and 7 (2.9%) versus 3 (1.3%) for bleeding. The differences between the rates were not significant. Early precutting can be preferable in prolonged cannulation trials of therapeutic ERCP.  相似文献   
109.
OBJECTIVE: Stroke is an acute neurologic dysfunction of vascular origin, characterized by loss of voluntary movement, sensory disturbances, and neurologic findings in the contralateral half of the body. Acute and long-term complications because of immobilization are seen in all organ systems. The aim of this study was to determine any differences between the affected and unaffected sides' bone mineral densities of acute and chronic stroke patients. DESIGN: In this study, we determined the bone mineral densities (BMD) of 30 male patients with acute (0-20 days) and 30 male patients with chronic (6 months or longer) stroke and compared the densities with the normal side. Upper and lower limb BMDs were measured by dual-energy x-ray absorptiometry. Additionally, patients were evaluated for the degree of spasticity, the phases of motor improvement, and the activities of daily living. RESULTS: In acute-phase stroke patients, BMD of the affected side was not significantly different from BMD of the normal side. BMD of both upper limbs of acute stroke patients was not different from normal side upper limb BMD of chronic stroke patients. In both acute and chronic stroke patients, affected and unaffected side lower limb BMDs (femur total BMD scores) were not significantly different. However, in chronic stroke patients, affected side BMD of Ward's region was significantly higher compared with the normal side. There is no correlation between BMD and Brunnstrom phases, Ashworth scales, and the degree of activities of daily living. CONCLUSIONS: Higher BMD of the affected side Ward's region in chronic cerebrovascular accident patients may be related to spasticity and changes in walking pattern, which increase the mechanical stress loading of the Ward's region.  相似文献   
110.
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