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31.
A P Hemingway 《Blood reviews》1989,3(3):147-151
Angiodysplasia, a condition of unknown aetiology, is thought to represent the commonest cause of obscure gastrointestinal bleeding, particularly in the elderly population. The lesions of angiodysplasia, which are small (less than 5 mm) and usually multiple, consist of microvascular abnormalities in the mucosa and submucosa of the bowel wall. They are most commonly found in the caecum and right side of the colon, but have been observed in the stomach, ileum and elsewhere in the colon. The diagnosis is made by either selective visceral angiography and/or colonoscopy, but the lesions cannot be detected on barium studies or with the naked eye at laparotomy. Localisation of the abnormalities by the histopathologist is greatly facilitated by special injection techniques demonstrating the blood vessels of resected colonic specimens prior to fixation and section. Treatment may be conservative (iron replacement) if the anaemia is not severe, by endoscopic fulguration or by colonic resection. Other common causes of gastrointestinal blood loss should always be excluded before the final diagnosis of angiodysplasia is accepted. Although the condition is well recognised as a significant cause of gastrointestinal blood loss a number of questions remain to be answered. The true incidence of angiodysplasia in the population is not known, the aetiology of the condition remains a mystery, although many theories abound. 相似文献
32.
Enayati AA Lengeler C Erlanger T Hemingway J 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2005,99(5):369-378
A recombinant glutathione S-transferase (GST)-based pyrethroid quantification assay was field-tested in Ifakara, Tanzania. Initial laboratory tests suggested that all reagents used in the assay should be sufficiently stable for field use, provided that domestic refrigeration facilities were available. Insecticide-impregnated bednets were collected from a region where a social marketing programme was in progress. A total of 100 bednets were collected and the assay plus standard HPLC analysis was performed on the residues extracted from four replicate areas of each net. Insecticide residue estimations for assays performed on white and pale green bednet samples were accurate when compared with residue analysis by HPLC. However, for dark green or blue bednets, there was no correlation between the GST-based assay and HPLC pyrethroid quantification results. The assay failure with the dark coloured nets was caused by the extraction of the dyes along with the insecticide, which subsequently interfered with the GST assay. When the same samples were analysed by HPLC, the dyes were separated from the insecticide by reverse phase column chromatography and hence did not affect the results. 相似文献
33.
Computed tomography of hilar cholangiocarcinoma: a new sign 总被引:18,自引:0,他引:18
D H Carr N S Hadjis L M Banks A P Hemingway L H Blumgart 《AJR. American journal of roentgenology》1985,145(1):53-56
Thirty-seven patients with histologic proof of cholangiocarcinoma at the confluence were examined by computed tomography (CT) to determine whether this examination is of value in the assessment of these patients for surgery and whether there are any features specific to this type of tumor. Thirty-two patients showed intrahepatic duct dilatation; six of these showed dilatation of ducts in one lobe only. Eighteen patients had intrahepatic low-attenuation areas, while eight had a mass lesion in the porta hepatis. Two of the lesions in the porta hepatis and four of the low-attenuation lesions enhanced. Atrophy of a lobe was noted in seven patients. This feature is not commonly recognized and is suggestive of cholangiocarcinoma rather than other hepatic tumors. The results of this study show that CT provides useful anatomic information preoperatively but that the appearances are nonspecific. Lobar atrophy is highly suggestive of hilar cholangiocarcinoma, either of long-standing or with unilateral portal venous involvement. 相似文献
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37.
Fitzpatrick NK Shah S Walker N Nourmand S Tyrer PJ Barnes TR Higgitt A Hemingway H 《Social psychiatry and psychiatric epidemiology》2004,39(2):154-163
OBJECTIVE: The aim of this study was to determine the factors associated with receipt of different levels of shared care, and the effect of shared care on patient outcomes. METHOD: A total of 349 patients with severe mental illness were selected from general practice lists. Patient functioning was assessed using standardised questionnaires, and GPs completed a questionnaire about patients' shared care arrangements at baseline (response-rate 79%). Patients were followed up at 12 months. RESULTS: Receipt of high shared care was associated with greater patient satisfaction with services and social functioning at baseline (p < 0.005). Patients receiving high shared care showed greater improvements in SF-12 mental health scores at follow-up compared to low shared care groups (p = 0.02). This effect was abolished after adjustment for age, sex and psychiatric diagnosis. CONCLUSION: Receipt of high shared care was not associated with demographic or clinical characteristics. High shared care had limited value for patients in terms of improved clinical, social or general health functioning over one year. 相似文献
38.
Successful treatment of oesophageal candidiasis by micafungin: a novel systemic antifungal agent 总被引:5,自引:0,他引:5
Pettengell K Mynhardt J Kluyts T Lau W Facklam D Buell D;FK South African Study Group 《Alimentary pharmacology & therapeutics》2004,20(4):475-481
AIM: To determine the minimum effective dose and safety of micafungin in the treatment of HIV-related oesophageal candidiasis. METHOD: A total of 120 patients were enrolled in this open label study of the effects of daily 1 h infusions of micafungin on endoscopically proven fungal oesophagitis. Patients were randomly assigned to receive 12.5, 25, 50, 75 and 100 mg of micafungin daily. Response was evaluated clinically and endoscopically. RESULTS: The protocol defined minimum effective dose of micafungin was 12.5 mg. The percentage of patients experiencing clearing of physical signs and symptoms showed a dose-response relationship and reached 94.7% in the 100 mg dose group. All patients in the 50, 75 and 100 mg dose groups achieved an endoscopically verified improvement in oesophagitis. Adverse effects of micafungin were generally mild and not dose-related. No serious renal, hepatic or drug-related infusion reactions were encountered. CONCLUSION: Micafungin was found to be effective, well-tolerated and safe. The minimum effective dose was found to be 12.5 mg and a significant linear trend in the successful treatment of oesophageal candidiasis was observed across the doses used with 75 and 100 mg dose levels achieving high rates of clinical and endoscopic cure. 相似文献
39.
Resistance-associated point mutations of organophosphate insensitive acetylcholinesterase,in the olive fruit fly Bactrocera oleae 总被引:5,自引:0,他引:5
Vontas JG Hejazi MJ Hawkes NJ Cosmidis N Loukas M Janes RW Hemingway J 《Insect molecular biology》2002,11(4):329-336
A 2.2-kb full length cDNA containing an ORF encoding a putative acetylcholinesterase (AChE) precursor of 673 amino acid residues was obtained by a combined degenerate PCR and RACE strategy from an organophosphate-susceptible Bactrocera oleae strain. A comparison of cDNA sequences of individual insects from susceptible and resistant strains, coupled with an enzyme inhibition assay with omethoate, indicated a novel glycine-serine substitution (G488S), at an amino acid residue which is highly conserved across species (G396 of Torpedocalifornica AChE), as a likely cause of AChE insensitivity. This mutation was also associated with a 35-40% reduction in AChE catalytic efficiency. The I199V substitution, which confers low levels of resistance in Drosophila, was also present in B. oleae (I214V) and in combination with G488S produced up to a 16-fold decrease in insecticide sensitivity. This is the first agricultural pest where resistance has been associated with an alteration in AChE, which arises from point mutations located within the active site gorge of the enzyme. 相似文献
40.
Diabate A Baldet T Brengues C Kengne P Dabire KR Simard F Chandre F Hougard JM Hemingway J Ouedraogo JB Fontenille D 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2003,97(6):713-716
In Anopheles gambiae, as in most species of mosquitoes, mating is initiated in flight. The males aggregate in aerial swarms and conspecific females individually fly to these swarms where they mate with males. In this study, we investigated the swarming behaviour of A. gambiae and conducted 2 surveys in the rice field area of the Vallée du Kou in Burkina Faso in 1999 and 2002. A high number of anopheline mosquitoes were observed in this area and both molecular M and S forms of A. gambiae were found in sympatry. Swarms formed a few minutes after sunset in different places and no obvious markers were associated with their occurrence. However, swarms occurred close to cow herds generally in open flat areas, 2-3 m above the ground. Overall, 2829 anopheline mosquitoes were collected from 21 swarms composed primarily of males. A few specimens of Culex quinquefasciatus were collected from 3 swarms. Although both molecular M and S forms were found in sympatry in the village, swarms were composed almost exclusively of the molecular M form. This suggests that there are alternative swarming habits for both molecular M and S forms of A. gambiae in nature. 相似文献