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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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A 15-year-old girl presented de novo in diabetic ketoacidosis having been comatose for 24 h (day 1). A CT scan and lumbar puncture performed on admission were normal and her conscious level slowly improved over several days. On day 7 she had central neurological signs of bilateral knee clonus and an extensor plantar response. In addition, she had developed lower motor neurological signs of an ulnar nerve palsy of the left forearm, and ulnar, median, and radial nerve palsies of the right forearm. Magnetic resonance imaging (MRI), performed on day 12, showed multiple small cerebral haematomata with appearances at least several days of age. The scattered lesions were localized particularly to the parieto-occipital region, with sparing of the basal ganglia and without cerebral oedema, a novel feature not previously described in juvenile ketoacidosis. Four months later there was minimal residual disability of her right arm. The clinical findings together with the MRI images suggested that the peripheral nerve and central lesions were temporally related, suggesting a common aetiology. However, it is likely that MRI showed cerebral lesions which may have been missed by the conventional CT scanning performed initially.  相似文献   
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用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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The comparison of disease risk in populations stratified by certain demographic variables provides important clues as to the underlying causes of disease. There are fundamental variations in the risk of occurrence of different cancers by gender, area of residence, and time of diagnosis. Men are, for instance, at considerably higher risk of developing most of the common cancers that occur in both sexes, and there are substantial variations in the occurrence of particular cancers in different regions of the World. This paper attempts to highlight some of these remarkable variations using cancer incidence data by sex, area of residence and year of diagnosis, emphasising the strong evidence that many of the contrasts can be appropriated to a number of modifiable “environmental” factors.Rates of cancer occurrence in the developed world are double that of less developed regions, although risk patterns are of very different magnitude and direction depending on the cancer site examined. Lung cancer is the most common neoplasm in men globally, but is overshadowed by prostate cancer in certain westernised countries, notably in the U.S. Cancers of the colon and rectum are important in the developed world, whereas stomach and liver cancer are common in developing areas.Men have systematically higher rates than women for the vast majority of the tumours that develop in both sexes, with the exception of thyroid cancer. There are also huge variations in the extent of the inequality: men have notably elevated risks, relative to women, of developing tumours of the head and neck, bladder, lung, oral cavity and liver.In Europe, incidence trends of lung cancer tend to be declining in men, although there is substantial between-country variation. In women, lung cancer rates are systematically on the increase in most Western, Southern and European countries. Trends in prostate cancer are increasing, as are trends in colorectal cancer (in both sexes), although more noticeably in Southern and Eastern Europe. Stomach cancer continues to fall in most European areas. Bladder cancer is decreasing in both men and women, apart from in Eastern Europe, whereas cancers of the kidney and non-Hodgkin lymphoma are steadily increasing in both sexes.We have estimated that men have better and more readily achievable prospects of avoiding death from cancer since they have lower rates of gender specific cancers, that are probably hormonal in origin, then women. Tobacco consumption plays a dominating role in the excess risk of cancer in men but it is apparent that the male excess disease burden can be effectively reduced by various prevention measures. As well as avoiding (or quitting) smoking, these include, moderating alcohol consumption, avoiding obesity, undertaking regular physical exercise, and maintaining a diet high in fruit and vegetables. The adoption of a healthier lifestyle will be of considerable benefit to the general health of both men and women, with an expectation of a major reduction in the burden of cancer, as well as other major diseases.  相似文献   
8.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
9.
The expression of somatostatin receptors 1 and 2 in benign, pre‐malignant and malignant laryngeal lesions The role of chemotherapy in squamous cell carcinoma of the larynx has not been clearly defined. Whilst toxic chemotherapy regimes may confer a marginal improvement in survival, surgery and radiotherapy remain the mainstay of treatment. Somatostatin is a naturally occurring peptide, which exerts antiproliferative and antiangiogenic effects via five membrane‐bound receptor subtypes. The expression of somatostatin receptor subtypes (SSTRs) 1 and 2 was studied in benign, pre‐malignant and malignant laryngeal specimens. Epithelial expression of SSTR1 was detected in 4/6 (67%) Reinke's oedema, 5/6 (83%) pre‐malignant and 8/12 (67%) malignant specimens, with virtually no stromal or vascular expression. High levels of epithelial SSTR2 expression were noted in all Reinke's oedema specimens, compared with low‐to‐moderate levels in only 2/6 (33%) pre‐malignant and 3/12 (25%) malignant specimens (P < 0.01). This ‘loss’ of epithelial SSTR2 expression may provide a growth advantage in pre‐malignant and malignant laryngeal lesions. Vascular expression of SSTR2 was ubiquitous in all groups, with scant stromal expression. Overall, most (>80%) pre‐malignant and malignant laryngeal specimens expressed at least one of the two SSTR subtypes studied. Somatostatin analogues may have a therapeutic role in squamous cell carcinoma of the larynx.  相似文献   
10.
Y Niv  C Turani  E Kahan  GM Fraser 《Gastroenterology》1997,112(6):2104-2107
Polycystic kidney disease is an autosomal dominant disease that may be associated with cystic disease of the liver. In women, the cysts may develop early and be more troublesome than in men. Cystadenocarcinoma of the pancreas is uncommon, comprising 1% of primary pancreatic malignancies. This case report is the first to describe a familial association between polycystic kidney disease and cystadenocarcinoma of the pancreas and liver in the English medical literature. A patient with autosomal dominant polycystic kidney disease (ADPKD) and multiple hepatic cysts developed cystadenocarcinoma of the pancreas with multiple malignant liver cysts. The patient's mother, sister, and niece had ADPKD, and the patient's sister also died of pancreatic cystadenocarcinoma. We believe that the development of these two disease entities in which the primary pathology is cyst formation has a genetic association. (Gastroenterology 1997 Jun;112(6):2104-7)  相似文献   
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