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排序方式: 共有496条查询结果,搜索用时 15 毫秒
101.
CE Swenson WR Perkins P Roberts I Ahmad R Stevens DA Stevens AS Janoff 《Canadian Metallurgical Quarterly》1998,42(4):767-771
BACKGROUND: Second primary malignancies are common after bilateral retinoblastoma; their estimated incidence has been as high as 51% 50 years after diagnosis. Fifteen patients who developed sebaceous gland carcinoma after radiation therapy have been reported in the literature, five of whom were treated for bilateral retinoblastoma. METHODS: The authors conducted a retrospective chart review of patients treated for bilateral retinoblastoma at Duke University Medical Center who later developed sebaceous gland carcinoma. RESULTS: This article reports two patients who developed sebaceous gland carcinoma after radiation therapy for bilateral retinoblastoma. CONCLUSIONS: Delay in diagnosis is often associated with sebaceous gland carcinoma. Because high mortality is observed with metastatic disease, the recognition of this association is important for anyone who follows patients with a history of bilateral retinoblastoma or prior cranial radiation therapy. 相似文献
102.
A primary malignant pulmonary hemangiopericytoma was diagnosed in a 45-year-old woman who complained of 10 months of cough and exertional dyspnea. One year after resection of the mass, a metastatic lesion was removed from the contralateral lung. The literature on this unusual pulmonary lesion is reviewed. 相似文献
103.
A nested polymerase chain reaction (PCR)-based assay, for detection of bluetongue virus (BTV) ribonucleic acid in cell culture and tissue samples, was developed. Two pairs of oligonucleotide primers (BTV1 and BTV4 and BTV2 and BTV3), selected from non-structural protein 1 (NS1) gene of BTV-17, were used for the nested PCR in two amplification steps. First a 826-bp product was amplified using an outer primer pair BTV1 and BTV4. The second amplification, using nested or internal primer pair BTV2 and BTV3, produced a 517-bp PCR product. RNA from North American prototype serotypes 2, 10, 11, 13 and 17, propagated in cell cultures, were detected by this nested PCR-based assay. The nested primers BTV2 and BTV3 increased the sensitivity of the BTV PCR assay, and as little as 0.1 fg of BTV RNA (equivalent to 5 viral particles) could be detected. Amplification products were not detected when the PCR-based assay was applied to RNA from a closely related orbivirus, epizootic hemorrhagic disease virus (EHDV) prototype serotypes 1 and 2; total nucleic acid extracts from uninfected BHK-21 cells; or whole blood from calves and deer that were BTV-seronegative and virus isolation negative. Application of this nested BTV PCR-based assay to clinical samples resulted in detection of BTV RNA from a variety of tissues collected from calves and deer with natural and experimental BTV infections. The described BTV PCR-based assay provides a valuable tool to study the epidemiology of BTV infection in susceptible wild ruminants and domestic livestock. 相似文献
104.
105.
The human selenium status in 10 locations of Irkutsk region (n = 216) is estimated using serum and hair selenium as biological markers. Extremely low serum selenium was typical for the inhabitants of Angara area (63-84 mcg/l). Hair selenium varied from 504 mcg/kg to 718 mcg/kg, the lowest values being found in Shelehov and Angarsk, the highest--in Karam and Mama. Low selenium concentrations were found also in the main food products: cereals--49-89 mcg/kg, meat--234-489 mcg/kg of dry weight, bread--106-180 mcg/kg of dry weight. 相似文献
106.
Sufentanil is a highly lipid soluble opioid that provides potent analgesia when administered in the subarachnoid space. Unfortunately, the penetration of sufentanil into the cerebrospinal fluid (CSF) after epidural administration is poor, and limits its effectiveness for epidural analgesia. Dural puncture may enhance the movement of epidural sufentanil into the subarachnoid space and increase its effectiveness. To determine whether the administration of epidural sufentanil adjacent to a dural puncture results in significantly greater CSF concentrations, 18 adult ewes were studied. Animals in the control group had an epidural catheter placed at the superior border of the pelvis without dural puncture. Animals in the study group had an epidural catheter placed, followed by a dural puncture performed using an 18-gauge Touhy needle. The dural puncture was performed one interspace cephalad to the epidural catheter. One hour after dural puncture, each animal received a loading dose of 0.35 microg/kg of sufentanil (5 microg/mL) through the epidural catheter, followed by an infusion of epidural sufentanil 0.15 microg x kg(-1) x h(-1) for a period of 4 h. After 4 h, CSF was sampled from a site one interspace caudad to the epidural catheter as well as at the cisterna magna. The mean CSF concentration of sufentanil at the level of the pelvis for animals with a dural puncture was 12.1 +/- 3.0 ng/mL compared with 1.8 ng/mL in controls with intact dura. Sufentanil concentrations at the cisterna magna were below the level of detection (0.08 ng/mL) for all animals in both groups. We conclude that an 18-gauge dural puncture significantly increases movement of sufentanil from the epidural to the intrathecal space. This increase in sufentanil concentration at the level of the pelvis was not associated with detectable levels of sufentanil at the brainstem. Implications: This study addresses the effect of dural puncture on spinal fluid concentrations of sufentanil after epidural administration. A sheep model was used to measure drug concentrations in the spinal fluid at the levels of the pelvis and brainstem after epidural administration. Dural puncture significantly enhanced movement of sufentanil into the spinal fluid at the level of the pelvis, but brainstem concentrations were below the level of detection. Analgesic concentrations of spinal sufentanil in the clinical setting, as well as brainstem concentrations associated with respiratory depression, have yet to be defined. 相似文献
107.
A Landers IE Murdoch J Birch SN Cousens OE Babalola B Lawal A Abiose BR Jones 《Canadian Metallurgical Quarterly》1998,82(5):510-516
OBJECTIVE: To study the effect of growth hormone (GH) treatment (2-4 months) on insulin action in adipocytes isolated from children with Prader-Willi syndrome (PWS), in whom GH deficiency appears to be a primary defect. We investigated the complex effects of GH on carbohydrate metabolism, as part of a current clinical trial of GH treatment in children with PWS. METHODS: Biopsies of subcutaneous abdominal adipose tissue were obtained from 12 children with PWS before and after 2-4 months of GH treatment. Lipogenesis was determined by the incorporation of radiolabelled glucose into lipids in isolated adipocytes, and glycerol release to the incubation medium was used as an index of lipolysis. GLUT4 RNA was measured by solution hybridization. RESULTS: With low glucose concentrations, at which glucose transport is rate-limiting, maximal insulin-induced lipogenesis was increased by 120% after GH treatment (P < 0.05), but the sensitivity to insulin (half-maximum effective hormone concentration) was unchanged. This was not accompanied by a significant change in the RNA expression of GLUT4. Neither responsiveness (maximum effect) nor sensitivity of insulin-induced inhibition of lipolysis was affected by GH treatment. CONCLUSIONS: GH treatment of children with PWS results in an upregulation of insulin-induced lipogenesis in isolated adipocytes, with no effect on insulin-induced inhibition of lipolysis. The data suggest that the site of the effect of GH on lipogenesis is distal to the insulin hormone-receptor interaction, but does not involve altered GLUT4 expression. 相似文献
108.
Several studies have suggested that if a calf vein thrombosis does not propagate above the knee when followed up with serial diagnostic studies, full anticoagulation may not be necessary. These studies have not included spinal cord injured patients. Two patients with spinal cord injury were diagnosed with acute calf vein thrombosis after admission to a spinal cord injury rehabilitation unit. Both patients refused intravenous heparinization. Serial duplex Doppler studies were performed on both patients to evaluate for propagation of thrombus. Neither patient developed propagation of thrombus, pulmonary embolus, or persistent thrombophlebitis. Full anticoagulation including intravenous heparinization is costly, subject to complications, and interferes with intensive rehabilitation therapies. Observation of calf vein thrombosis with appropriate serial follow-up studies may be a viable alternative to anticoagulation in spinal cord injured patients. Further studies need to be done with this unique patient population. 相似文献
109.
110.
To evaluate the activity of benzoylphenyl urea chitin biosynthesis inhibitor chlorfluazuron (IKI-7899) against Parasarcophaga argyrostoma, seven doses were topically applied (once) onto early third (last) instar larvae, puparia, or newly formed pupa: 150, 100, 50, 10, 1.0, 0.5, and 0.25 microgram/insect. After topical treatment of last instar larvae, the highest mortality was caused by both higher doses and the lowest mortality was caused by the lowest dose. The lethal activity of IKI-7899 as pronouncedly decreased as the treatment was lately carried out (at the puparial time). IKI-7899 failed to cause cumulative mortality because no pupal or adult mortalities were observed, irrespective of the time of treatment. Treated larvae suffered the action of IKI-7899 because they had decreased weight gain. Except the lowest dose, the weight gain of larvae inversely correlated with the dose-levels. IKI-7899 prolonged not only the larval duration but also the pupal duration after topical treatment of last instar larvae with doses 50-0.25 micrograms/larva. With no exception, all doses topically applied onto puparia or newly formed pupae enhanced pupae to live longer. Topical application onto last instar larvae resulted in different degrees of reduction of pupation rate, but IKI-7899 could not affect the pupal morphogenesis after larval treatment except by its highest dose which led to 8.33% pupal deformities and 7.69% larval-pupal intermediates. The dose 100 micrograms/larva topically applied onto last instar larvae detained 7.69% of what known as "permanent larvae" which suffered the action of the compound along 16 days and eventually perished without any external feature of puparium formation. A metamorphic effect of IKI-7899 pronouncedly appeared in the adult stage. Three higher doses completely arrested the adult flies. Topical application of the compound onto prepupae did not greatly reduce the pupation rate especially at the doses 50, 10 and 1.0 micrograms/puparium. The dose 50 micrograms/puparium was only the dose halting the pupal moulting program because 7.14% of permanent prepupae remained about 12 days and then died. In respect to adult emergence, the highest dose led to zero rate and the lowest dose allowed to all pupae to emerge without malformation. 相似文献