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61.
半导体红外激光光凝治疗视网膜静脉阻塞   总被引:7,自引:0,他引:7  
为探讨半导体红外激光对视网膜静脉阻塞(RVO)的治疗效果,对58例RVO患者用Keeler公司“Microlase”半导体激光器(波长810nm)作区域封闭或全视网膜光凝(PRP)。结果:17例中央视网膜静脉阻塞(CRVO)患者,治疗前后平均视力分别为0.175及0.40;7例半球阻塞(Semi-CRVO)患者治疗前后平均视力为0.116及0.40;34例视网膜分枝静脉阻塞(BRVO)患者则分别为0.19及0.465。经t检验,差别均有显著性。结论:激光光凝治疗是RVO重建供氧平衡的重要手段,疗效肯定。半导体红外激光有比氩激光更易穿透浑浊介质和更少影响视网膜神经纤维层和黄斑功能等优点。早期进行区域封闭或全视网膜光凝,有利于保存有用视力。  相似文献   
62.
Summary The binding of3H-WB 4101, an 1-adrenoceptor antagonist, to membranes of the cerebral cortex, the hypothalamus, and the lower brainstem was examined in adult spontaneously hypertensive (SH) rats and in normotensive Wistar Kyoto (WK) controls. The specific binding of3H-WB 4101 (0.33 nM) was significantly higher in homogenates from the cerebral cortex of SH rats as compared to WK rats. No differences were detected between SH and WK rats in the specific binding of3H-spiroperidol (0.25 nM), a dopamine receptor antagonist, to membranes from the corpus striatum and the limbic forebrain. The locomotor activity was significantly higher in SH rats as compared to WK controls, in all probability due to a lack of habituation to environmental change. It is suggested that the high reactivity of SH rats is related to a dysfunction in the noradrenergic neurons in the central nervous system.  相似文献   
63.
64.
Medulloblastoma in children and in adults: a comparative study   总被引:1,自引:0,他引:1  
Summary We report on the clinical and pathological characters and factors influencing prognosis in a consecutive series of 20 cases of medulloblastoma presenting in childhood and of 20 cases of the tumour presenting in adulthood. The significant differences which emerged were compared with the findings of the largest published series. Medulloblastoma is more often lateral in site and desmoplastic in histology in adults than in children. On our evidence the age at tumour onset not affect survival.  相似文献   
65.
Summary It was demonstrated that the simplified ergot congener 8-hydroxy-2-(di-n-propylamino)tetralin, 8-OH-DPAT, is able to elicit pronounced biochemical and behavioural alterations indicative of central serotoninomimetic activity. Since these effects are resistant to prior monoamine depletion and/or synthesis inhibition by means of reserpine and-propyldopacetamide (H22/54), respectively, they are most likely to be attributable to direct serotonin-receptor agonism by 8-OH-DPAT. With regard to central 5-HT neurotransmission the effects of 8-OH-DPAT-increased 5-HT levels, decreased 5-HIAA levels, 5-HT-synthesis rate and 5-HT utilization and inhibited 5-HT neuronal firing-are virtually identical, and comparable in potency, to those reported to result from the administration of lisuride or LSD. In contrast, however, to lisuride and LSD (included for comparative purposes in this study) as well as to several differently N-substituted, 5,6-dihydroxy, 6,7-dihydroxy and 5-, 6- and 7-monohydroxy 2-aminotetralins, 8-OH-DPAT lacks appreciable effects on central catecholamine receptors. The compound may thus be regarded the most potent, selective centrally acting 5-HT agonist described to date. accordance with this it was shown that the full-blown 5-HT-like behaviour syndrome induced by 8-OH-DPAT cannot be antagonized by reserpin phenoxybenzamine, propranolol and haloperidol. In addition, of the truputative 5-HT-receptor blockers cyproheptadine, methergoline and methrothepin only the latter was able to counteract the 8-OH-DPAT-induce syndrome. The results are discussed in relation to the recent subclassification of central 5-HT receptor sites.A comparison between the chemical structures and biological activities for different fragments of the ergot nucleus was also made. The data suggest, in that while the role of the A ring in the ergot structure for dopaminer activity at present is unclear, this ring may be important for the 5-HT-receptor activity like in e.g. lisuride and LSD.Moreover, based on the present results and literature reports, it is speculated that a selective 5-HT-receptor agonist such as 8-OH-DPAT would be liable to induce hallucinations in man.Presented in part at the 19th ACNP meeting, San Juan, December 15–19,1980. [Psychoph. Bull.17, 180–183 (1981).]  相似文献   
66.
Summary Clonidine is able to increase the threshold for vocalisation during stimulation and the threshold for vocalisation after withdrawal of stimulus (vocalisation afterdischarge). These effects of clonidine were investigated after treatment of rats with drugs influencing central monoaminergic and cholinergic mechanisms.Chlorpromazine, atropine and p-chlorophenyl-alanine increased the activity of clonidine at both thresholds while phenoxybenzamine and reserpine pretreatment increased the activity at the threshold for vocalisation only.Yohimbine decreased clonidine activity at both thresholds while 5-HTP and -methyl-p-tyrosine decreased the effects at the threshold for vocalisation afterdischarge. Naloxone did not change the activity of clonidine at either pain response studied.It is concluded from the present findings that influence from several neuronal systems modulate the antinociceptive action of clonidine.The inhibition of the medullary nociceptive response after clonidine might be connected to a decreased activity of noradrenergic neurons. Endogenous noradrenaline seems to be of minor importance in mediating this effect. It is moreover shown that decreased cholinergic receptor activity enhances clonidine antinociceptive action on both medullary and diencephalic-rhinencephalic pain responses. The possible involvement of serotonin in these functional responses after clonidine is also discussed.Data from this investigation was presented at the International Narcotic Research Club Conference, Airlie, Va. 1975.  相似文献   
67.
颈动脉斑块与心脑血管阻塞性疾病关系的临床探讨   总被引:5,自引:1,他引:5  
目的 探讨颈动脉斑块与心脑阻塞性疾病及视网膜中央动脉阻塞(CRAO)的关系。方法 1995年10月至2002年7月采用彩色多普勒超声对我院心脑血管疾病患者149例行颈动脉检查。结果 检出颈动脉斑块者74例,未检出斑块者75例。有斑块者较无斑块者颈动脉内膜中层厚度明显增加(P<0.01)。结论 颈动脉斑块严重程度的增加,其内膜中层厚度亦呈增厚趋势。前者是造成脏器梗死的重要原因之一。颈动脉斑块的检测和治疗可作为心脑血管及CRAO疾病的重要预防措施。  相似文献   
68.
BACKGROUND: The complication rate of central venous totally implantable access ports (TIAP), used for high-dose chemotherapy with autologous stem cell transplantation support, has not been fully investigated to date, due to the almost exclusive use of externalised, tunnelled devices in this clinical setting. PATIENTS AND METHODS: During a 66-month period (from 1 January 1997 to 30 June 2002), 376 patients suffering from breast cancer, ovarian cancer, lymphoma or multiple myeloma were treated with high-dose chemotherapy and autologous stem cell transplantation at the European Institute of Oncology (Milan, Italy). A single type of port was used, constructed from titanium and silicone rubber, connected to a 7.8 F polyurethane catheter (Port-A-Cath; SIMS Deltec, Inc., St Paul, MN, USA) inserted into the subclavian vein. They were followed prospectively for device-related complications until the device was removed, the patient died or the study was closed (30 June 2002). RESULTS: No TIAP-related deaths were observed in this series. Seven pneumothoraxes (1.8%) occurred as a complication of TIAP placement, one patient only (0.2%) requiring a tube thoracostomy. Port pocket infection occurred twice in this series (0.53%, 0.01 episodes/1000 days of use), whereas three patients suffered from port-related bacteraemia (0.8%, 0.016/1000 days of use). Infections were successfully treated with antibiotics; all three cases had the ports removed at programme completion. Four cases of deep vein thrombosis were detected (1.06%, 0.022/1000 days of use); low molecular weight heparin was given, followed by oral anticoagulants. Finally, one case of extravasation occurred (0.26%, 0.005/1000 days of use), requiring port removal and local medical therapy. CONCLUSIONS: The use of TIAPs has resulted in a safe and effective option for high-dose chemotherapy deliverance and stem cell transplantation, in spite of inducing severe neutropenia and increasing the risk of sepsis in this category of oncology patient.  相似文献   
69.
Leptomeningeal carcinomatosis is an uncommon but devastating form of metastatic spread. To our knowledge, only 16 cases originating from a head and neck cancer have been reported. We describe the first case of a patient with leptomeningeal carcinomatosis arising from a laryngeal squamous cell carcinoma. Shortly after completing treatment for an advanced supraglottic laryngeal cancer, this 63‐year‐old man presented with lower limb neurological symptoms and signs. Radiological and cytological evidence of leptomeningeal carcinomatosis of the distal spinal canal was identified. He was treated with intrathecal methotrexate and palliative radiotherapy. Although his pain improved, his lower limb weakness worsened. He died 3 weeks after completing radiotherapy. Presumed mode of spread was via the haematogenous route. The natural history and management of leptomeningeal carcinomatosis are discussed. Clinicians should be aware of the uncommon possibility of leptomeningeal carcinomatosis in a patient presenting with an appropriate constellation of symptoms and signs, and a past history of cancer.  相似文献   
70.
Immunohistochemistry profiles of medulloepithelioma (from two 2 1-year-old girls who had 2 cerebral medulloepitheliomas and a 35-week postconceptional female infant with congenital posterior fossa tumor) and neural tube are compared. Microscopically, the tumors contained a medulloepitheliomatous component, manifested as tubular epithelial structures lined by pseudostratified columnar epithelium delineated by well-defined basement membranes. In all cases, glial and neuronal differentiation were noted to differing extents. The medulloepitheliomatous components did not exhibit glial fibrillary acidic protein, neuron-specific enolase, or S-100 protein reactivity. Neurofilament, cytokeratin, and epithelial membrane antigen were focally present in one case. Extensive nestin immunopositivity was confined to the basal cell layer of the epithelium, leaving the luminal surface unreactive or slightly reactive. These cells also displayed a reactivity to vimentin and to microtubuleassociated protein type 5 similar to that of cells of the primitive neural tube. The similarity between the immunohistochemical profile of medulloepithelioma and that of neural tube epithelium suggests a possible reexpression of that component of the genome responsible for neural tube growth and differentiation in medulloepithelioma.  相似文献   
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