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1.
A case of synovial sarcoma in the abdominal wall of a 50-year-old Iraqi woman is reported. The ultrastructure of the tumor has been studied. Eight other cases of synovial sarcoma in the abdominal wall reported in the English literature up to 1978 have been reviewed. Synovial sarcomas in the abdominal wall tend to occur with a much greater frequency in women, whereas such tumors occurring in the extremities or the neck are more common in men than woman. No ultrastructural studies of abdominal wall synovial sarcomas could be found in the English literature. The ultrastructural characters of this tumor are similar to those of such tumors arising in the usual sites and the neck. However, the present study has indicated that the light and dark cells reported by earlier workers are not limited solely to the epitheloid areas but are also present in the spindle cell zones.  相似文献   
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The fully developed laminar flow of a viscous non-Newtonian fluid in a rough-walled pipe is considered. The fluid rheology is described by the power–law model (covering shear thinning, Newtonian, and shear thickening fluids). The rough surface of the pipe is considered to be fractal, and the surface roughness is measured using surface fractal dimensions. The main focus of this study lies in the theoretical investigation of the influence of the pipe surface roughness on the velocity profile and the Darcy friction factor of an incompressible non-Newtonian fluid. The plotted results demonstrate that shear thinning fluids are the most sensitive to the surface roughness compared with Newtonian and shear thickening fluids. For a particular value of the surface fractal dimension, there exists an intersection point where shear thinning, Newtonian, and shear thickening fluids behave the same way regarding the amplitude of the velocity profile and the friction factor. This approach has a variety of potential applications, for instance fluid dynamics in hydrology, blood flow in the cardiovascular system, and many industrial applications.  相似文献   
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AIM: To compare the success, clinical outcomes, and maternal and neonatal complications between the Kiwi Omnicup and the Malmstrom metal cup in vacuum assisted delivery. METHODS: This was a prospective randomized comparative trial. Women who required vacuum assisted vaginal delivery were randomized into the Kiwi Omnicup (KO) group and the Malmstrom metal cup (MM) group. The vacuum assisted deliveries were conducted according to hospital protocol. Details of the procedure and delivery outcomes including success and complications were analyzed. RESULTS: One hundred and sixty-four women were recruited - 85 were assigned to vacuum assisted delivery using the KO and 79 the MM. One hundred percent delivery success was achieved with no significant differences between the two instruments in terms of maternal morbidity (P = 0.66). Six women in the MM group sustained post delivery complications in comparison to five in the KO group. Three babies were diagnosed with birth asphyxia in each group. More babies in the MM group were admitted to the Neonatal Intensive Care Unit (NICU) (10 babies versus 5 babies) and suffered complications (14 versus 12 babies), compared to the KO group, although the difference was not statistically significant. There were no intrapartum or neonatal deaths and of those admitted to the NICU, all were discharged within a week without any serious consequences. CONCLUSION: Kiwi Omnicup is an effective alternative to the currently available Malmstrom metal cup for vacuum assisted delivery with no increase in maternal or neonatal morbidity or mortality.  相似文献   
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The aim of this observation was to report a rare case of symptomatic and non-functional cystic parathyroid adenoma in a 52-year-old female, diagnosed with imaging and treated by surgical resection of the gland.  相似文献   
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Post-kala-azar dermal leishmaniasis (PKDL) is a complication of visceral leishmaniasis (VL) and serves as a potential reservoir for Leishmania parasite. The study was aimed to evaluate the spectrum of skin lesions of PKDL in kala-azar endemic areas in Bangladesh. This cross sectional study was carried out to observe the characteristics of skin lesions among 250 PKDL cases. The suspected PKDL patients in highly endemic villages of Fulbaria Upazilla of Mymensingh district.were subjected to a dipstick test (rK39) for kala azar. The median time interval between diagnosing kala-azar and PKDL was 23 month (m-21, r- 0-60 months). The most common skin lesions were multiple symmetrical hypopigmented macules with irregular margins in 179(71.6%) cases followed by erythematous facial induration in 74(29.6%), papular in 33(13.2%), nodular in 28(11.2%) cases, combination of macules, papules, nodules and plaques in 88(35.2%) cases, annular in 7(2.8%) cases and Papillomatous mucosal growth in 2(0.8%) cases. Sites of involvement were mostly in face (92.4%), Trunk (84.8%), extremities (33.2%), oral mucosa and tongue (0.8%) and Genitalia (1.2%). Suspicion of PKDL on the basis of skin lesions will lead to early diagnosis and prompt treatment will impart an important role in prevention and eradication of Leishmaniasis in Bangladesh.  相似文献   
7.
The entraining and distribution of air voids in the concrete matrix is a complex process that makes the mechanical properties of lightweight foamed concrete (LFC) highly unpredictable. To study the complex nature of aerated concrete, a reliable and robust prediction model is required, employing different machine learning (ML) techniques. This study aims to predict the compressive strength of LFC by using a support vector machine (SVM) as an individual learner along with bagging, boosting, and random forest (RF) as a modified ensemble learner. For that purpose, a database of 191 data points was collected from published literature, where the mix design ingredients, i.e., cement content, sand content, water to cement ratio, and foam volume, were chosen to predict the compressive strength of LFC. The 10-K fold cross-validation method and different statistical error and regression tools, i.e., mean absolute error (MAE), root means square error (RMSE), and coefficient of determinant (R2), were used to evaluate the performance of the developed ML models. The modified ensemble learner (RF) outperforms all models by yielding a strong correlation of R2 = 0.96 along with the lowest statistical error values of MAE = 1.84 MPa and RMSE = 2.52 MPa. Overall, the result suggests that the ensemble learners would significantly enhance the performance and robustness of ML models.  相似文献   
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The cyanobacterium Synechocystis aquatilis was observed growing as a monospecies in enriched phytoplankton samples in the laboratory, indicating its allelopathic activity on coexisting phytoplankton species. Therefore, the present study screened the culture medium of an axenic strain of this cyanobacterium for the presence of allelechemicals with algicidal properties by thin-layer chromatography (TLC). The allelopathic effect of S. aquatilis was evaluated by co-cultivation of target species of toxic cyanobacteria and green algae with this cyanobacterium, as well as by evaluation of norharmane (β-carboline 9H-pyrido(3,4-b) indole) crude extract prepared from the culture medium of Synechocystis. The growth of target algal species was measured as a cell density after 6 days incubation. The results showed that S. aquatilis produced the indole alkaloid norharmane with large quantities in the culture medium (86 μg l?1). In co-cultivation experiments, S. aquatilis inhibited the growth of all tested cyanobacteria and green algae. Norharmane crude extract exhibited stronger inhibition of cyanobacteria (EC50 = 4.6–4.8 μg ml?1) than green algae (EC50= 6.3–6.4 μg ml?1) in a concentration-dependent manner, indicating its apparent role in the allelopathic activity of S. aquatilis. The possible applicability of the allelochemical, norharmane, as an algicide to prevent the formation of harmful algal bloom was discussed.  相似文献   
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