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41.
The expression of epidermal growth factor receptor (EGF-R) in 34 formalin fixed paraffin embedded specimens of malignant mesothelioma was examined using the F4 antibody. Eight samples of reactive pleura showed homogenous cytoplasmic staining with the antibody. EGF-R positive cells (greater than or equal to 5%) were found in 68% of the mesotheliomas examined. EGF-R positivity was more commonly seen in the epithelial histological subtype than in the sarcomatous or mixed subtypes. Patients with less than 5% of mesothelioma cells staining positive for EGF-R had a significantly shorter survival (median 299 days) compared with patients whose tumours had a greater number of cells positive for EGF-R (median 446 days) (P = 0.04). However, when the histological subgroup was also taken into consideration (epithelial type had a significantly longer survival than the sarcomatous or mixed) the survival difference in relation to EGF-R positivity was no longer significant (P = 0.08). EGF-R could not be used to distinguish between malignant and benign mesothelial tissue and was not an independent prognostic factor for survival.  相似文献   
42.
The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (VMCA) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P  = 0.042) and in the postinfusion period (30–90 min) ( P  = 0.027). Carbachol infusion caused a drop in VMCA ( P  = 0.003) and an increase in STA diameter ( P  = 0.006), but no increase in the RA diameter ( P  = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects.  相似文献   
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44.
Genetic predisposition to human lung cancer   总被引:9,自引:0,他引:9  
The influence of polymorphic variants of the human c-Ha-ras gene on predisposition to lung cancer has been investigated. The human c-Ha-ras gene has been shown to reside on a polymorphic BamH1 restriction fragment. This restriction fragment length polymorphism (RFLP) results from variation in the size of a region of repetitive DNA 3' to the gene. An attempt has been made to characterise and compare the c-Ha-ras RFLP's in a normal population and in a group of cancer patients. DNA was extracted from the white blood cells of 101 normal donors and four common Ha-ras alleles identified, with occasional rare alleles of various sizes. The allele frequencies were examined in 132 lung cancer patients, comprising 66 individuals with small cell carcinoma of the lung (SCCL) and 66 with non-small cell carcinoma of the lung (non-SCCL). An abnormal allele distribution was found in individuals with non-SCCL compared to both control and SCCL values suggesting a degree of genetic pre-position to non-SCCL. In addition, analysis of the Ha-ras RFLP's in solid samples inferred a deletion of material from the short arm of chromosome 11 in two of 16 informative samples.  相似文献   
45.
Increased oxidative stress is a mechanism that probably plays a major role in the development of diabetic complications, including peripheral neuropathy. This review summarises recent data from in vitro and in vivo studies that have been performed both to understand this aspect of the pathophysiology of diabetic neuropathy and to develop therapeutic modalities for its prevention or treatment. Extensive animal studies have demonstrated that oxidative stress may be a final common pathway in the development of diabetic neuropathy, and that antioxidants can prevent or reverse hyperglycaemia-induced nerve dysfunction. Most probably, the effects of antioxidants are mediated by correction of nutritive blood flow, although direct effects on endoneurial oxidative state are not excluded. In a limited number of clinical studies, antioxidant drugs including alpha-lipoic acid and vitamin E were found to reduce neuropathic symptoms or to correct nerve conduction velocity. These data are promising, and additional larger studies with alpha-lipoic acid are currently being performed.  相似文献   
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47.
Eight patients with cutaneous T cell lymphomas (CTCL) and five with various other T cell malignancies were treated with mouse monoclonal antibody (MoAb) T101. Doses of 1 to 500 mg were administered weekly over a two-hour period and resulted in one complete remission (convoluted T cell lymphoma) and one partial remission (CTCL). Remission duration was 6 weeks and 3 months, respectively. Frequent toxicities were pruritus, hives, flushing, and shortness of breath. Supraventricular arrhythmias and blood pressure instability were also observed. Complete targeting of peripheral blood T cells was achieved with 1 mg of MoAb in the nonleukemic patients (WBC less than 10,000/microL), and free, bioavailable antibody was present at the next (10-mg) dose level. Even higher doses resulted in substantial antibody excess that persisted for as long as 6 weeks. Serum concentrations of MoAb decreased with increasing number of peripheral blood T cells, and 25 to 35 mg of T101 were required for induction of antibody excess in leukemic patients. Excess antibody induced antigenic modulation, which was of consequence only if MoAb excess persisted to the next treatment. In the original treatment, the rapidly administered MoAb was able to target and remove peripheral blood T cells before the development of antigenic modulation. Antimouse antibodies developed in three patients. Their presence rendered further therapy ineffective and was associated with an anaphylactic reaction in one patient. Development of these antibodies could not be predicted by lymphoproliferative assays. In these assays, however, the T101 protein strongly stimulated the mononuclear cells of the patient who reached the only complete remission of this trial. Immunologic stimulation by the MoAb thus might have played a role in this patient's antitumor response. In summary, therapy with MoAb T101 was specific but only modestly efficacious. Rapid infusion of nonmodulating doses of antibody provided excellent targeting and removal of peripheral blood T cells and might be a valid approach in future trials with immunoconjugated T101.  相似文献   
48.
Thirteen patients with malignant mesothelioma of the pleura have been treated with 24-hour cyclophosphamide infusion (2.5 g/m2) therapy. There were no complete responders. Three patients (23%) had a partial response, and a further three patients who did not fulfil the criteria for objective response, had subjective benefit from therapy with increase in performance status. The overall median survival from the onset of therapy was 6 months (range 2-19 months). High dose cyclophosphamide offers no advantage over standard dose therapy.  相似文献   
49.
细粒棘球蚴重组抗原B的表达提取及其血清学检测初探   总被引:4,自引:0,他引:4  
用基因工程技术制备出的细粒棘球绦虫重组抗原B(rAgB)表达载体,经诱导表达、亲和层析纯化获得具生物活性的重组蛋白质rAgB,用Western-Blot法检测病人血清。结果显示rAgB敏感性为91.6%(44/48),特异性为93.8%(30/32),其中10例泡球蚴(AE)病人及10例肿瘤病人血清均无交叉反应。说明rAgB具有较高的敏感性及特异性,可用于包虫病的常规血清学诊断,rAgB在宿主菌JM109内稳定表达,因此可在实验室内大量制备用于血清学诊断的rAgB。  相似文献   
50.
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