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Rhizoxin is a tubulin-binding anti-neoplastic agent which is active in a range of murine tumour models. The recommended schedule, of intravenous (i.v.) bolus administration at a dose of 2 mg m-2 every 3 weeks, has been assessed in three phase II trials of ovarian, renal and colorectal cancer. In general terms the drug was fairly well tolerated, but the response rate was disappointing: 0/18, colorectal cancer; 0/18, renal cancer; 1 partial response (PR)/17, ovarian cancer.  相似文献   
23.
A historical survey into the occupational hazards of mining and refining arsenic is presented together with the measures adopted for their control. The industry is placed in the social perspective of its time and it is suggested that this experience could be of value to those who may encounter similar problems where arsenic is extracted elsewhere in the world.  相似文献   
24.
Parapelvic renal cysts are uncommon in children. We report a case occurring in a 2-year-old girl, diagnosed during follow-up for blood hypertension. The cyst measured 8 cm in length. There was associated hydronephrosis, due to obstruction of the renal pelvis. Surgical resection was performed. Normotension returned within 3 months, and the obstruction disappeared. A renovascular mechanism can be evoked to explain hypertension.  相似文献   
25.
In Wales, predictive testing for Huntington's disease (HD) has not been offered proactively to families and uptake of testing is low in comparison to other centres. Little is known of those not requesting testing, particularly those not in direct contact with the genetics service. This study examined differences between a cohort of 22 test applicants and a random group of 32 'non-requesters', drawn from the South Wales HD register. Respondents were interviewed by means of a semi-structured schedule in their own homes. The study groups differed significantly on a number of variables including: knowledge of the availability of testing; perceived attitudes of family members and significant others to testing; length of knowledge and perceived stressfulness of being at risk; and perceived ability to cope with an unfavourable result. Overall, knowledge of testing procedures was poor and at-risk individuals' understanding of genetic terminology was at odds with scientific distinctions. Discussion focuses on the organisational and psychological factors associated with lack of knowledge of the availability of testing and the interpretation of reported coping capacities.  相似文献   
26.
A case of infantile agranulocytosis with survival into adolescence is presented. The polymorphonuclear leukocyte is considered an important source of lysosomal enzymes in gingival crevicular fluid, and evaluation of connective tissue-degrading enzymes in the fluid was performed. The activity of beta-glucuronidase, a ground substance-degrading enzyme that may serve as a marker for polymorphonuclear leukocytes, was markedly reduced in the fluid compared to samples from systemically healthy adults with periodontitis. The activities of the ground substance-degrading enzyme arylsulfatase, and collagenase, were in the low-normal range. The plaque microbiology, as characterized by dark-field microscopy and selective culturing, was consistent with advanced periodontitis. A review of the medical history revealed a series of bacterial infections since infancy. Improvement in the systemic health of the patient occurred at about the age of 15, and the intake of antibiotics to control infections was correspondingly reduced after this time. An exacerbation of the patient's periodontal disease, as evaluated by loss of alveolar bone on radiographs, occurred 1 to 2 years later. The progression of periodontal disease observed in this patient was apparently associated with the withdrawal of antibiotics administered for control of systemic (nonoral) infections.  相似文献   
27.
M Miros  P Kerlin  N Walker  J Harper  S Lynch    R Strong 《Gut》1991,32(11):1369-1373
Patients with primary sclerosing cholangitis are at an increased risk of developing cholangiocarcinoma, which is difficult to diagnose because the biliary tree is already distorted. Eleven patients with primary sclerosing cholangitis who underwent orthotopic liver transplantation at this hospital were evaluated. Four patients had coincidental histologically proved cholangiocarcinoma. Patients with cholangiocarcinoma in contrast to patients without tumour presented with rapid onset of persistent jaundice, pruritus, and weight loss associated with an appreciable rise in bilirubin (8x v 2x) and alkaline phosphatase (3.5x v 1.2x) over one year. Cholangiography and computed tomography showed appreciably dilated intrahepatic bile ducts (3/4 v 0/7). The diagnosis of cholangiocarcinoma could only be established before operation in one patient by fine needle aspiration cytology. Tumour was recognised at operation in one other. Histological examination of hepatectomy specimens showed that patients with cholangiocarcinoma had less advanced histological features of primary sclerosing cholangitis. Multiple areas of carcinoembryonic antigen positive epithelial atypia and carcinoma in situ were found in all patients with cholangiocarcinoma. Cholangiocarcinoma recurred in two patients at 14 and 39 months after transplantation. Superimposed cholangiocarcinoma can be predicted in most patients with cholangitis before transplantation, although a definitive diagnosis is difficult to make. Their prognosis after successful transplantation is guarded.  相似文献   
28.
Neck manipulation may uncommonly be associated with serious and even fatal vascular complications. Although well recognised, the nature of the vascular injury has only rarely been directly established by pathological examination. The case is reported of a 43-year-old man who died following neck manipulation, and in whom multiple dissecting aneurysms within both vertebral arteries were demonstrated radiologically and found at necropsy. Bilateral dissecting aneurysms were found both at the level of atlanto-axial articulation and close to the origins of the vertebral arteries. No predisposition was found, other than early atheroma consistent with the patient's age.  相似文献   
29.
30.
Summary The pharmacokinetics of single intravenous and oral doses of L-carnitine 2 g and 6 g has been investigated in 6 healthy subjects on a low carnitine diet.Carnitine was more rapidly eliminated from plasma after the higher dose. Comparing the 2-g and 6-g doses, the t1/2 of the elimination phase () was 6.5 h vs 3.9 h, the elimination constant was 0.40 vs 0.50 h–1 and the plasma carnitine clearance was 5.4 vs 6.11 × h–1 (p<0.025), thus showing dose-related elimination.Saturable kinetics was not found in the range of doses given. The apparent volumes of distribution after the two doses were not significantly different and they were of the same order as the total body water. Urinary recoveries after the 2-g and 6-g doses were 70% and 82% during the first 24 h, respectively.Following the two oral dosing, there was no significant difference in AUCs of plasma carnitine. Urinary recoveries were 8% and 4% for the 2-g and 6-g doses during the first 24 h. The oral bioavailability of the 2-g dose was 16% and of the 6 h dose 5%. The results suggest that the mucosal absorption of carnitine is already saturated at the 2-g dose.  相似文献   
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