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91.
Isolated intracranial Rosai-Dorfman disease mimicking meningioma   总被引:2,自引:0,他引:2  
Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease (RDD), is an idiopathic histiocytic proliferation affecting lymph nodes. It is typically characterized by painless cervical lymphadenopathy, fever and weight loss. Although extranodal involvement has been reported in diverse sites, intracranial presentation, particularly in the absence of nodal disease is uncommon. To the best of our knowledge, 48 patients with intracranial masses have been reported previously. A 31-year-old man was admitted to our clinic with a 4-month history of progressive headache. His medical history was unremarkable except for occasional fever. There were not any neurological deficit and weight loss. No lymphadenopathy (particularly bilateral cervical) and extranodal involvement in diverse sites were revealed by physical and radiological examinations. Routine hematological and biochemical studies were normal except for mild leukocytosis and elevated erythrocyte sedimentation rate. The patient underwent magnetic resonance imaging (MRI) testing that revealed an enhancing mass in the left temporal lobe. Preoperative diagnosis was meningioma. The patient underwent a left frontotemporal craniotomy with complete resection of the mass. Histopathology was compatible with RDD. Extranodal RDD is rarely found intracranially. Prognosis is benign especially in the absence of nodal disease. It is clinically and radiologically difficult to distinguish from meningioma, and histological examination is essential for a definitive diagnosis.  相似文献   
92.
Alzheimer's disease is the major cause of dementia in humans. The affected brain shows characteristic abnormal filamentous proteins that accumulate intracellularly as neurofibrillary tangles, and extracellularly as senile plaques, as well as in cerebral blood vessels. The extracellular deposits are an amyloid protein, which is highly insoluble. In our study, we intended to show that the N-terminus of amyloid A4 protein can change in length and sequence in Alzheimer's disease, and possibly in other dementias.  相似文献   
93.
We examined the effect of subacute methidathion (MD) administration on vascular wall damage and evaluated the ameliorating effects of combination of vitamins E and C against MD toxicity. The experimental groups were: rats treated with corn oil (control group), rats treated with 5 mg/kg MD (MD), and rats treated with 5 mg/kg body weight MD plus vitamin E and vitamin C (MD+Vit). The groups were given MD by gavage on 5 days a week for 4 weeks at a daily dose 5 mg/kg (MD and MD+Vit) using corn oil as the vehicle. Vitamins E and C were injected at doses of 50 mg/kg intramuscularly and 20 mg/kg intraperitoneally, respectively, after the treatment with MD in the MD+Vit group. The levels of malondialdehyde (MDA) were determined in the aortic tissue. Histopathological examination was examined in the thoracic aortic tissue. MDA levels were higher in the MD group than the control group and lower in the MD+Vit group than MD group. MD administration led to irregulation, prominent breaks, and fragmentation of the elastic fibers but decrease in the irregulation and fragmantation of the elastic fibers with the combination of vitamins E and C in MD-treated rats. In conclusion, it is likely that subacute MD administration caused vascular wall damage, and that treatment with a combination of vitamins E and C after the administration of MD can reduce vascular wall damage caused by MD.  相似文献   
94.
There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.  相似文献   
95.
We evaluated the electrophysiological and histopathological effects of low-energy gallium arsenide (904 nm) laser irradiation on the intact skin injured rat sciatic nerve. Twenty-four male Wistar rats were divided into three groups (n=8 each). At the level of proximal third of the femur the sciatic nerve was crushed bilaterally with an aneursym clip (Aesculap FE 751, Tuttingen, Germany) for half a second. A gallium arsenide laser (wavelength 904 nm, pulse duration 220 ns, peak power per pulse 27 W, spot size 0.28 cm2, pulse repetition rate 16, 128 and 1000 Hz; total applied energy density 0.31, 2.48 and 19 J/cm2) was applied to the right sciatic nerve for 15 min daily at the same time on 7 consecutive days. The same procedure was performed on the left sciatic nerve of same animal, but without radiation emission, and this was accepted as control. Compound muscle action potentials were recorded from right and left sides in all three groups before surgery, just at the end of injury, at the 24th hour and on the 14th and 21st days of injury in all rats using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara, USA). BIOPAC Acknowledge Analysis Software (ACK 100 W) was used to measure CMAP amplitude, area, proximal and distal latency, total duration and conduction velocity. Twenty-one days after injury, the rats were sacrificed. The sciatic nerves of the operated parts were harvested from the right and left sides. Histopathological evaluation was performed by light microscopy. Statistical evaluation was done using analysis of variance for two factors (right and left sides) repeated-measures (CMAP variables within groups) and the Tukey–Kramer Honestly Significant Difference test (CMAP variables between laser groups). The significance was set at p 0.05. No statistically significant difference (p 0.05) was found regarding the amplitude, area, duration and conduction velocity of CMAP for each applied dose (0.31, 2.48 and 19 J/cm2) on the irradiated (right) side and the control (left) side, or between irradiated groups. Twenty-one days after injury there were no qualitative differences in the morphological pattern of the regenerated nerve fibres in either irradiated (0.31, 2.48 and 19 J/cm2) or control nerves when evaluated by light microscopy. This study showed that low-energy GaAs irradiation did not have any effect on the injured rat sciatic nerve.  相似文献   
96.
 The purpose of this study was to investigate the associations of tooth loss with skeletal bone mass, years since menopause, educational level, current smoking status, dietary calcium intake, and number of pregnancies in postmenopausal osteoporotic women in Turkey. The study population consisted of 1171 postmenopausal women aged 40–86 years (mean age, 61.19 ± 7.28 years). A detailed history was obtained from all women, including relevant lifestyle parameters, risk factors, and measurements of weight and height. Women were separated into three groups according to the number of teeth remaining as group 1 (edentulous, 457 women), group 2 (10 or fewer teeth, 232 women), and group 3 (more than 10 teeth remaining, 482 women). There was no significant difference among the three groups in mean age and menopausal age (P < 0.05). Body mass index of group 1 was significantly higher than that of group 2 (P < 0.01). Educational level was significantly different between three groups: groups 1 and 2 (P < 0.001), groups 1 and 3 (P < 0.0001), and groups 2 and 3 (P < 0.001). Educational level was lowest in group 1 and highest in group 3. Despite a low ratio of cigarette smoking in general, a smoking habit was most prevalent in group 3 and least in group 2. The ratio of women receiving adequate calcium was significantly lower in group 1 than in other groups (P < 0.001); mean calcium intake was similar in all groups. The number of pregnancies was significantly higher in group 1 than in other groups (P < 0.001). Lumbar bone mineral density (BMD) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001). Although no significant difference was found between groups 1 and 3, femoral neck BMD of group 2 was less than in others, and differences between groups 1 and 2 and between groups 2 and 3 (P < 0.001) were significant. Lumbar bone mineral content (BMC) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001), and lumbar BMC in group 2 was significantly higher than in group 3 (P < 0.05). Femoral neck BMC in group 1 was significantly higher than in groups 2 and 3 (P < 0.001). In conclusion, lumbar BMD and BMC in the edentulous group were significantly lower, whereas femoral neck BMD and BMC were significantly higher in edentulous group compared with the others. Our findings indicated that improvement in lifestyle factors and nutritional strategies for the treatment and prevention of osteoporosis may have additional benefit in reducing tooth loss. Received: February 18, 2002 / Accepted: June 21, 2002 Offprint requests to: A. Gur  相似文献   
97.
BACKGROUND & AIMS: Spontaneous bacterial infection and septicemia due to increased bacterial translocation (BT) in patients with obstructive jaundice result in significant morbidity and mortality. The present study evaluates the effects of enteral nutrition with immune enhancing feeds on BT and intestinal villus histopathology promoted by obstructive jaundice. METHODS: Fifty male Wistar-albino rats weighing 250-300g were assigned into five equal groups of 10. Animals in Groups I, II, and III were fed with standard chow, those in Group IV were given glutamine 1g/kg/day and the remaining 10 animals in Group V were fed with an arginine, omega-3 fatty acids, and RNA-supplemented enteral diet for (1g/kg/day amino acid and 230 kcal/kg) 7 days preoperatively. Group I underwent sham operation and the remaining animals in all other groups underwent common bile duct ligation. After operation, Group I had standard chow, Groups II and IV had glutamine, Groups III and V had an arginine omega-3 fatty acids, and RNA-supplemented enteral diet for 7 days. All animals were sacrificed on the 8th postoperative day and evaluated both biochemically and histopathologically. Samples from blood, liver, mesenteric lymph nodes and spleen were cultured under aerobic conditions. RESULTS: Significantly less BT was observed in groups fed with an arginine, omega-3 fatty acids, and RNA-supplemented enteral diet or glutamine in pre-and postoperative periods as compared to others (P<0.001). Histologic evaluation also showed significant reduction in villus atrophy in these groups. CONCLUSIONS: Enteral immunonutrition using glutamine or arginine, omega-3 fatty acids, and RNA-supplemented enteral diet during both pre-and postoperative periods seems to reduce BT and decrease atrophy of intestinal mucosal villi in rats with obstructive jaundice.  相似文献   
98.
Durmus M  Ender G  Kadir BA  Nurcin G  Erdogan O  Ersoy MO 《Anesthesia and analgesia》2003,96(5):1336-9, table of contents
Tracheal intubation may be accomplished with remifentanil and a non-opioid IV anesthetic without a muscle relaxant. In this study, we evaluated in double-blinded, prospective, randomized manner the dose requirements for remifentanil with thiopental without muscle relaxant administration to obtain clinically acceptable intubation conditions and cardiovascular responses. After premedication with midazolam 0.03 mg/kg IV, 105 patients were randomized equally to one of three study groups, each receiving the following: remifentanil 2 micro g/kg (Group I), 3 micro g/kg (Group II), and 4 micro g/kg (Group III). Remifentanil was administered over 30 s, and anesthesia was induced with thiopental 5 mg/kg. Tracheal intubation conditions were assessed by the anesthesiologist performing the intubation as: (a) excellent, (b) satisfactory, (c) fair, and (d) unsatisfactory. There were no statistically significant differences among groups regarding to demographic data. Blood pressure and heart rate did not increase in any group after accomplishing intubation. There was a significant improvement in intubation conditions between Groups I and II, I and III, and II and III (P < 0.001). We conclude that remifentanil 4 micro g/kg administered before thiopental 5 mg/kg provided excellent or satisfactory intubation conditions in 94% of patients and prevented cardiovascular responses to intubation. IMPLICATIONS: We evaluated in a double-blinded manner the dose requirements for remifentanil with thiopental without muscle relaxants for obtaining acceptable intubation condition. Our results show that remifentanil 4 micro g/kg administered before thiopental provided excellent or satisfactory intubation condition in 94% of patients.  相似文献   
99.
OBJECTIVE: To compare the technical benefits of grasper-assisted laparoscopic splenectomy (LS) with traditional LS. METHODS: The study comprised 27 consecutive patients who were admitted to our hospital from 1998 to 2002 and underwent LS: 13 patients underwent traditional LS (group 1), and 14 had grasper-assisted LS (group 2). RESULTS: In both groups, the most common indication for LS was idiopathic thrombocytopenic purpura. There was no difference between the groups in the demographic characteristics of patients. All splenectomies were performed in the right semidecubitus position, using four or five trocars. Conversion to open surgery was required in one patient (7.7%) in group 1 and in one patient (7.1%) in group 2. Both conversions occurred during the initial 16 operations and no conversion occurred during the subsequent 11 operations. The mean operating time was significantly shorter for group 2 (132 minutes) than for group 1 (154 minutes) (P <.005). Mean estimated blood loss (201 vs. 282 mL) was also lower in group 2 than in group 1 (P <.05). The mean length of hospital stay was 3.3 days in group 1 and 2.4 days in group 2 (P >.05). CONCLUSION: Grasper-assisted LS is both safe and feasible in patients with hematologic diseases. This technique can be preferred in order to grasp and position the spleen during the surgery.  相似文献   
100.
Primary multiple chest wall hydatid cysts associated with spinal canal involvement through an intervertebral foramen is an uncommon clinical entity. We present a 54-year-old man who underwent cystotomy and total resection of ribs five through seven via a left posterolateral thoracotomy followed by Th5-Th6 anterolateral partial pediculotomies for removal of cysts in the spinal canal. Although spinal reconstruction was not required, the chest wall defect was repaired with mersilene mesh-methyl methacrylate sandwich graft. Hydatid disease should be considered in the differential diagnosis of mass lesions located in the chest wall. In cases of spinal canal involvement, detailed visualization of spinal canal utilizing MRI and/or CT is essential for planning surgical approach.  相似文献   
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