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61.
Summary A simple technique of stereotactic craniotomy and intraoperative lesion localisation that uses the Brown-Robert-Wells (BRW) stereotactic frame is presented. The method optimises craniotomy placement and facilitates localisation of small intracerebral lesions. Using the system, 16 patients have had resection of intracranial neoplasms from deep and/or eloquent areas of the brain with no neurological morbidity. 相似文献
62.
采用异相氯磺化的方法,使聚乙烯(PE)中空纤维膜进行氯磺化反应,并将反应产物进一步水解和离子交换,可获得具有离子交换功能的磺化聚乙烯(SPE)中空纤维离子交换膜。应用渗透蒸发膜分离方法,研究磺化聚乙烯中空纤维离子交换膜对水/乙二醇混合物的分离效果。讨论了反离子的种类、渗透蒸发分离温度和水/乙二醇混合液的组成等对磺化聚乙烯中空纤维离子交换膜的分离效果的影响。 相似文献
63.
Granular cell tumours rarely involve the lower respiratory tract. We report eight cases surgically resected at our institution. There were four females and four males, aged between 18 to 56 years (mean 40). One tumour associated with a peripheral lung adenocarcinoma was asymptomatic. The other lesions presented with obstructive pneumonitis (3 cases), haemoptysis (2), dyspnea (1) or cough (1). These tumours were tracheal (1) or bronchial (6) and one case was located in the lung parenchyma. Four cases were multicentric with associated lesions located in a bronchus (2), the oesophagus (1) or a mediastinal lymph node (1). All tumours, with the largest diameter ranging from 0.5–4.5 cm, were histologically invasive. The tumours were positive for S-100 protein, neuron specific enolase, KP1 (CD68) and vimentin. No tumour expressed desmin, keratin or p53 oncoprotein. Our study demonstrates that, in spite of marked anatomical and clinical polymorphism, the rare granular cell tumours of the lower respiratory tract have a constant histological appearance. Our observations confirm that large tumours (> 8–10 mm) usually extend beyond the tracheo-bronchial cartilages and, therefore, only surgical treatment may avoid recurrence. 相似文献
64.
目的观察重组人表皮生因子(rhEGF)对眼表上皮修复的影响及羊膜移植治疗翼状肉的疗效。方法对36例患者40眼的翼状肉施行肉切除-羊膜移植术,术后随机分为(rhEF治疗组(20眼)和药物赋型剂对照组(20眼),分别观察两组角膜上皮愈合速度和结膜上皮覆盖羊膜植片的愈合速度,对全部患者随访3-12个月。结果rhEGF治疗组术后角膜上皮愈合速度[(74983±1998)μm/h]显著高于对照组[(59372±17.197)μm/hP<0.01];rhEGF治疗组结膜上皮愈合速度[(36.584±7.888)μm/h显著高于对照组[(29.181±5.450) μmh,P<0.01]。随访全部病例未见复发,结论rhEGF可有效促进眼表上皮的损伤修复,羊膜移植为治疗翼状肉的较好方法。 相似文献
65.
本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。 相似文献
66.
Effect of exercise on plasma atrial natriuretic factor and cardiac function in men and women 总被引:1,自引:0,他引:1
J. E. DONCKIER P. M. DE COSTER M. BUYSSCHAERT P. LEVECQUE F. M. CAUWE C. M. BRICHANT A. C. BERBINSCHI J.-M. KETELSLEGERS 《European journal of clinical investigation》1988,18(4):415-419
In order to provide an integrated view of the physiology of atrial natriuretic factor (ANF) during exercise, we studied changes of its plasma concentrations in 13 normal subjects (seven males, six females) during three graded exercise levels and two periods of recovery (5 and 30 min), concomitantly with an assessment of cardiac function and ventricular volumes by multigated radionuclide angiography. Mean ANF levels (+/- SEM) increased in all patients at the second (P less than 0.002) and third (P less than 0.002) exercise levels, and after 5-min recovery (P less than 0.01): in males from 16 +/- 7 to 30 +/- 11 pg ml-1 at the third level, in females from 27 +/- 12 to 61 +/- 33 pg ml-1. Normal values were observed after 30-min recovery. Even if mean ANF levels were all higher in females, this difference did not reach statistical significance (P = 0.06). Significant decreases of ventricular volumes, as well as increases of ejection fraction and rate pressure product, were noted during exercise and were similar in both sexes. The kinetics of plasma ANF concentrations, compared with the increase of rate pressure product, was characterized by a latency and a remanence in recovery. This remanence, also present in the changes of ventricular volumes, supports the hypothesis that other factor(s) like catecholamines might still exert their influence after the exercise stops. 相似文献
67.
The optimal conditions for inactivation of Bordetella pertussis organisms with glutaraldehyde for the production of a safe and potent whole cell pertussis vaccine were investigated. Two bacterial harvests from B. pertussis strain 10536 were treated with glutaraldehyde, each with 0.025, 0.05 and 0.1% concentrations of glutaraldehyde for 10, 60 and 120 min. The nine types of glutaraldehyde-inactivated pertussis vaccine (GIPV) and conventional heat-inactivated pertussis vaccine (HIPV) preparations made from two bacterial harvests were comparatively evaluated for the mouse weight gain test (MWGT), potency, and the histamine-sensitization (HS) and leucocytosis-promoting-factor (LPF) tests. The minimum period for killing the B. pertussis organisms with glutaraldehyde was>10 min for 0.025%, 10 min for 0.05% and 5 min for 0.1% concentration. The average loss in opacity varied from 5 to 10% for GIPV preparations and was 14% for HIPV preparations. The GIPV preparations except those inactivated with 0.025% glutaraldehyde for 10 min (GIPV-A) were much less toxic than the HIPV preparations in the MWGT. The GIPV-A preparations did not pass the MWGT. The GIPV preparations were also much less toxic in HS and LPF tests than the HIPV preparation. The potency of GIPV preparations inactivated with 0.05% glutaraldehyde for 10 min (GIPV-D) was similar to that of HIPV preparations. The prolonged treatments with glutaraldehyde reduced the potency. The GIPV-D preparation with good potency and less toxicity was found to be inactivated with glutaraldehyde under optimal conditions. All the preparations were innocuous in the abnormal toxicity test. 相似文献
68.
大鼠肝细胞Ⅰ,Ⅲ型前胶原基因表达及PDGF的影响 总被引:3,自引:1,他引:2
目的观察大鼠肝细胞Ⅰ,Ⅲ型前胶原基因的表达及PDGF对其表达的影响.方法应用原位杂交技术检测分离培养的SD大鼠肝细胞(n=30)内Ⅰ,Ⅲ型前胶原基因的表达.同时观察10μg/L(n=30)和30μg/L(n=30)PDGF促进前胶原基因表达的作用.测定基因表达颗粒总面积占细胞总面积的百分比,并作比较分析.结果无论正常肝细胞或是在两种浓度的PDGF存在时,肝细胞内均可见到Ⅰ,Ⅲ型前胶原基因的表达.正常肝细胞Ⅰ,Ⅲ型前胶原基因表达面积的百分比(%)为77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成. 相似文献
69.
S. L. Grant P. A. Phillips C. B. Gow 《Clinical and experimental pharmacology & physiology》1994,21(3):243-247
1. Epidermal growth factor is a potent mitogen that causes natriuresis, diuresis and inhibition of arginine vasopressin-induced water reabsorption. 2. The aim of this study was to determine any interaction between epidermal growth factor and the V1 (vascular) and/or V2 (antidiuretic) arginine vasopressin receptor subtypes. 3. Radioligand binding displacement assays demonstrated that although arginine vasopressin related peptides displaced both radioligands from renal medullary membranes at low concentrations epidermal growth factor displaced neither. 4. Arginine vasopressin V2 receptor second messenger cyclic adenosine monophosphate (CAMP) production was inhibited by epidermal growth factor (IC50 2 ± 10?7 mol/L) as was sodium fluoride cAMP production but only at much higher concentrations. 5. Therefore the diuretic effect of epidermal growth factor is not via direct antagonism of arginine vasopressin receptors but seems mediated via inhibition of the V2 second messenger system. 相似文献
70.
Mark Ellis FRACO FRACS Ross Drewe MB BS DO † Justin O'Day FRACO FRACS 《Clinical & experimental ophthalmology》1994,22(2):119-123
Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM of the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasise readily. 相似文献