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61.
PURPOSE: To determine the magnetization transfer features of progressive multifocal leukoencephalopathy (PML) and human immunodeficiency virus (HIV)-associated white matter lesions (WML) (hereafter, HIV-WML) on magnetic resonance (MR) images obtained in patients with acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: Conventional MR imaging and magnetization transfer MR imaging were performed in 21 AIDS patients with 42 areas of white matter hyperintensity on MR images (13 patients had 25 PML lesions, eight patients had 17 WML). The magnetization transfer ratio was calculated for each lesion. RESULTS: Compared with normal-appearing white matter (magnetization transfer ratio = 47.9%), both PML and HIV-WML showed reduced magnetization transfer ratio. The magnetization transfer ratio was significantly lower in PML lesions (magnetization transfer ratio = 26.1%) than in HIV-WML (magnetization transfer ratio = 38.0%, P < .0001), and there was no overlap in the magnetization transfer ratio between PML lesions and HIV-WML. The separation in magnetization transfer ratio between the two lesion types was valid for lesion as small as 0.5 cm2. CONCLUSION: The larger reduction in magnetization transfer ratio for PML lesions is most likely due to demyelination, whereas the reduction in HIV-WML may be associated primarily with gliosis. PML lesions appear to cause strong reductions in magnetization transfer ratio early in the course of disease. Magnetization transfer MR imaging is a noninvasive tool that improves the differentiation between PML and HIV-WML in patients with AIDS. 相似文献
62.
4-N-Alkylamino derivatives and corresponding ammonium quaternary salts of tetrahydro-1,4-benzodiazepin-5-one were synthesized and evaluated for psychotropic activity in mice by ip via. This study was also extended to some nitro and amino derivatives of tetrahydro-1,4-benzodiazepin-5-one. Compounds were devoid of tranquilizing activity and in comparison with two classical benzodiazepines, chlordiazepoxide and diazepam, they showed high toxicity and little or no effect on motor coordination, motor activity, and maximal electroshock. On some "in vitro" tests the compounds exhibited pharmacological properties when they were used at high concentrations. 相似文献
63.
P. A. Le Witt D. B. Calne 《Journal of neural transmission (Vienna, Austria : 1996)》1981,51(1-2):175-184
Summary We have treated 102 Parkinson patients with bromocriptine for up to 6 years; most of these posed problems of management when referred to us. Forty-two continue to take bromocriptine, at a mean dose of 49 mg daily (range 10–160), in combination with some 50% of their previous optimal dose of levodopa (with or without a decarboxylase inhibitor). We consider the main indications for bromocriptine are severe dyskinesia, early morning dystonia, and wearing off reactions. Contraindications include hallucinations, delusions, substantial confusion, acute myocardial infarction, active peptic ulceration, and active pleuropulmonary disease. 相似文献
64.
65.
I Witt 《European journal of clinical chemistry and clinical biochemistry》1991,29(6):355-374
Since the early seventies, synthetic peptide substrates have been used in haemostaseology, enabling the introduction of photometry in coagulation analysis. Synthetic peptide substrates are short peptides (3-5 amino acid residues), with a chromogenic group coupled to the C-terminal end by an amide bond. The chromogenic group may be relatively specifically removed by proteases, and measured photometrically. By using the special properties of the many available substrates, test systems have been developed for procoagulant clotting factors, fibrinolytic factors, inhibitors of both systems and also for global tests of plasmatic coagulation. These tests can be performed manually or on automated analytical systems with high specificity, sensitivity and accuracy. The analytical advantages and new possibilities of the tests with chromogenic substrates have, in recent years, decisively stimulated not only haemostaseological basic research, but also clinical investigation and routine. Today, inhibitors of plasma coagulation (e.g. antithrombin III, protein C, C1-esterase inhibitor) as well as fibrinolytic parameters (e.g. tissue plasminogen activator, plasminogen activator inhibitor, alpha 2-antiplasmin) are nearly exclusively determined with chromogenic substrates. Further development will constitute the application of chromogenic substrates to "dry chemistry" methods. 相似文献
66.
67.
Zusammenfassung An Hand von 6 Fällen haben wir die Möglichkeiten der Verbundosteosynthese bei kniegelenksnahen Pseudarthrosen und Frakturen durch die intramedullären Stiele der Scharnierprothesen im Verbund mit Palacos sowie weiterem Osteosynthesematerial (Schrauben, Cerclagen) aufgezeichnet. Überzeugend ist die Möglichkeit der frühen Mobilisierung und Belastbarkeit nach derartigen Verbundosteosynthesen. Bei infizierten Kniegelenksendoprothesen halten wir den Austausch der Prothese nicht für geeignet, die Infektion zum Stillstand zu bringen. Hier sollte der Arthrodese der Vorzug gegeben werden.
Osteosynthesis with hinge joints and methylmethacrylate
Summary Six cases have been described where an osteosynthesis was performed using the stem of a hinge knee joint in combination with methylmethacrylate and other osteosynthetic devices (screws, wires). Need for an osteosynthesis existed because of pseudarthrosis after supracondylar and high tibial osteotomies, intraoperative fracture for implantation of a total knee, reimplantation after deep infection, and fatigue fracture after a total knee. The advantage of the procedure lies in early mobilisation and weight bearing. We do not believe in reimplantation after an infected prosthesis. Instead, we recommend fusion after implant removal.相似文献
68.
R Francavilla VL Miniello L Brunetti ME Lionetti L Armenio 《Acta paediatrica (Oslo, Norway : 1992)》2003,92(S441):101-104
A major complication of cholestasis is fat malabsorption related to decreased intestinal bile acids, which leads to malnutrition and fat-soluble vitamin deficiency. The impaired excretion of bile acids leads to a low intraluminal micellar concentration that causes long-chain triglyceride lipolysis and absorption to be ineffective. Medium-chain triglycerides (MCTs) are more readily absorbed when there are low concentrations of bile acids and therefore are a good source of fat calories; MCTs can be administered as MCT-containing formulas. In those children who are unable to take sufficient calories by mouth, it is important to start nocturnal enteral feeding to improve nutritional status. In infants with cholestasis, the absorption of fat-soluble vitamins (A, D, E and K) that require bile acids is also impaired, and supplementation is mandatory. Vitamin K deficiency may be responsible for hypoprothrombinaemia, which may lead to bleeding diathesis, Vitamin K (phytomenadione) should therefore be promptly administered intravenously, at a dose of 1 mg. Chronic vitamin E (α-tocopherol) deficiency is associated with a progressive neuromuscular syndrome that can cause cerebellar ataxia, areflexia and peripheral neuropathy. Supplements are given orally in doses of 3–5 times the normal requirement if cholestasis is incomplete. In complete cholestasis, supplements must be given intramuscularly at monthly intervals. In infants who fail to thrive, dietary supplements of carbohydrate polymers and MCTs are required. 相似文献
69.
中国健康志愿者单剂静滴甲磺酸加替沙星注射液的药代动力学 总被引:5,自引:0,他引:5
目的:研究中国健康成年男性志愿者单剂静滴甲磺酸加替沙星注射液的药代动力学。方法:按药物临床试验管理规范(GCP)指导原则设计试验方案。选择9名受试者分别依次单刘静滴100,200和400mg的甲磺酸加替沙星注射液后,应用HPLC测定血药浓度,采用3P97软件进行数据处理,求出药代动力学参数。结果:受试者分别给药后,药-时曲线符合二房室模型,主要药代动力学参数C_(max)分别为1.10±0.19,2.17±0.33和3.16±0.47mg·L~(-1);t_(1/2)β分别为7.42±1.99,8.41±2.72和8.46±2.83h;AUC_(0-∞)分别为4.45 ±0.71,11.10±1.81和23.03±3.83mg h·L~(-1)。原形药主要经肾排泄,48h尿药累积排泄率分别为(43.08±15.79)%,(51.33±23.69)%和(45.67±18.22)%。结论:9名静滴甲磺酸加替沙星注射液后,药-时曲线符合二房室模型。提示甲磺酸加替沙星在100~400mg剂量内药物体内过程基本呈线性动力学特征而无饱和性,主要排泄途径为肾脏。 相似文献
70.
原发性乳腺恶性淋巴瘤六例临床分析 总被引:8,自引:0,他引:8
目的 分析原发性乳腺恶性淋巴瘤的临床特点,探讨其诊断、分期和治疗方法。方法回顾分析我院自1995~2002年收治的6例原发性乳腺恶性淋巴瘤和1980~2002年国内主要文献报道的279例原发性乳腺恶性淋巴瘤的临床特征、诊断情况和治疗方法,进行对比分析。结果 285例病例均为非霍奇金淋巴瘤(NHL),免疫学检查证实有282例为B细胞源性(98.9%);女性268例,占94.0%;病灶位于右侧163例,占57.2%;Ⅰ期和Ⅱ期的原发性乳腺恶性淋巴瘤占89.8%。经手术、化疗、放疗等综合治疗后,生存期2~206个月,中位生存期最短23个月,最长56个月。结论 原发性乳腺恶性淋巴瘤绝大部分为B细胞源性非霍奇金淋巴瘤(NHL),Ⅰ期、Ⅱ期多见。对于原发性乳腺恶性淋巴瘤,诊断是关键,确诊后经手术、化疗、放疗等综合治疗,可以获得较长的生存期,疗效十分满意。 相似文献