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1.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
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A sensitive assay for human plasma BzAO, involving the conversion of 14C-benzylamine to 14C-benzaldehyde, was developed. MPTP and several of its analogues were found to be competitive inhibitors of the enzyme. Ki values for the MPTP analogues in the presence of human plasma BzAO were determined. The analogues had a different rank order of inhibition of human plasma BzAO compared with the rank order of inhibition of bovine plasma BzAO found previously. MPTP and 1-methyl-4-(2-methylphenyl)-1,2,3,6-tetrahydropyridine (2'-CH3-MPTP), which are potent nigrostriatal toxins, were weak inhibitors of human plasma BzAO.  相似文献   
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Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.  相似文献   
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Suppression of canine antral gastrin secretion by urine   总被引:1,自引:0,他引:1  
Distention of the gastric antrum with an alkaline fluid normally results in the secretion of gastrin. Following gastrocystoplasty in humans, however, hypergastrinemia has not been observed. We explored the possibility that a component of urine may suppress antral gastrin activity in the dog. Partial cystectomy and antral transposition to the bladder (ATB) was performed in five animals and antral transposition to the colon (ATC) was performed in five other dogs to serve as a hypergastrinemic controls. At four and eight weeks after surgery the mean serum gastrin levels in the ATC dogs were significantly greater than the mean preoperative levels (p less than 0.05). In contrast, at four and eight weeks after surgery the mean serum gastrin levels in the ATB animals were significantly less than the mean preoperative levels (p less than 0.05). The antral G-cell density as determined by immunohistochemical study at eight weeks after surgery was greater than normal in the ATC dogs but less than normal in the ATB dogs; but the differences did not achieve statistical significance. In another series of experiments using four other dogs a 4% aqueous peptone solution and a 4% peptone solution in concentrated dog urine were instilled into exteriorized antral pouches. The mean serum gastrin levels at 60 and 90 minutes after instillation of the former were significantly increased (p less than 0.05), but there was little or no change after instillation of the latter. Urine, or a component of urine, appears to suppress canine antral gastrin secretion and may explain the absence of hypergastrinemia following gastrocystoplasty in humans.  相似文献   
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The plating efficiency for fungal yeast cells is usually less than that expected from microscopic counts, and a number of explanations for this phenomenon have been proposed. The present study was undertaken to explore possible reasons for reduced plating efficiency of Candida albicans. Explanations that we evaluated and found unlikely included: ineffectiveness of different culture media and/or incubation temperatures for growing colonies, insufficient area of the plate available for expression of individual colonies, production of microcolonies, and inaccurate counting of the organisms in the inoculum. An assay for delivery of the inoculum into tissue culture plate wells indicated that reduced delivery of the organisms accounted for lower than expected plating efficiency. C. albicans yeast cells grown under low glucose conditions and expected to have reduced adhesiveness were found to have higher values for both delivery and plating efficiency in our assays. In summary, our results indicate that reduced plating efficiency for C. albicans under the conditions used for these experiments is best explained by the loss of some yeast cells during preparation of the inocula or delivery of the yeast cells onto the plates.  相似文献   
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Fasciolopsiasis is endemic in the far east. In India, there have been a few reports of the infection, prior to the 1990's. We report two cases from Azamgarh district of Uttar Pradesh. Both the cases were from nearby villages where water chestnuts are cultivated. These may be a source of infection. Pigs are commonly observed in these areas and and may be the source of ova. The only missing link is the finding of infected snails. Presence of at least three cases (one reported earlier) in the area indicates the potential for the infection to re-emerge. Further epidemiological studies are needed to analyse the various ecological factors of transmission. Fasciolopsiasis is endemic in China, Taiwan, Vietnam and Thailand. In India, (Fascilopsis buski) infections in man have been reported earlier from Assam, Maharashtra, Tamil Nadu and parts of Uttar Pradesh. However, to the best of our knowledge, no such reports have been made since 1990's. We herewith report two recent cases from district Azamgarh, Uttar Pradesh (U.P.), India. Factors, such as cultivation of water chestnuts, presence of snails as intermediate hosts and pigs as definitive host in this geographical area seem to be suggestive of an endemic focus and thus needs further epidemiological survey for preventive and control measures, at the earliest.  相似文献   
10.
Diarrhoeal diseases remain a major cause of mortality and morbidity in developing countries. However, due to lack of funds, supply problems and some inexperience, some laboratories have difficulty identifying a causative agent in stool samples. In the year following the opening of the Shaukat Khanum Memorial Cancer Hospital and Research Centre in Lahore, Pakistan, the microbiology department had not isolated a single enteric pathogen. From January 1996, new culture techniques were introduced, with a resulting increase (10%) in identification of these pathogens. In addition, the introduction of formol-ether concentration made a significant contribution to the number of intestinal parasites seen. This report demonstrates how simple microbiology methods made a difference to the running of the department and, ultimately, to the patients.  相似文献   
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