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131.
Granular cell tumor is a rare cause of hepatic dysfunction. We report here on a patient who underwent liver transplantation for this ailment. In our literature review, the common bile duct was most commonly involved (56%). A wide variety of therapies were advanced for this type of lesion, spanning three decades of care. Twenty-eight patients (49%) had no follow-up reported, and another 2 (3%) were found at autopsy. Sixteen patients (28%) were followed more than 1 year, with 72% followed less than 1 year if at all. We present the first case of a granular cell tumor being treated with liver transplantation. Although adequate early excisional surgery should obviate the need for transplantation in these cases, widely disparate therapy and poor follow-up may mask generally inadequate therapy for this lesion. The authors recommend thorough excision and long-term follow-up for patients with this entity to avoid secondary biliary cirrhosis and to eliminate the preventable need for transplantation. 相似文献
132.
Khaja Moiduddin Arshad Noor Siddiquee Mustufa Haider Abidi Syed Hammad Mian Muneer Khan Mohammed 《Materials》2021,14(22)
Applications of non-ferrous light metal alloys are especially popular in the field of aerospace. Hence it is important to investigate their properties in joining processes such as welding. Solid state joining process such as friction stir welding (FSW) is quite efficient for joining non-ferrous alloys, but with thick plates, challenges increase. In this study, Mg alloy plates of thickness 11.5 mm were successfully welded via single-pass FSW. Due to the dynamic recrystallization, grain size in the stir zone was reduced to 16 µm which is ≈15 times smaller than the parent material. The optimized rotational speed and traverse speed for optimum weld integrity were found to be 710 rpm and 100 mm/min, respectively. A sound weld with 98.96% joint efficiency, having an Ultimate Tensile Strength (UTS) of 161.8 MPa and elongation of 27.83%, was accomplished. Microhardness of the nugget was increased by 14.3%. 相似文献
133.
A.M.M. Hammad 《Journal of basic microbiology》1998,38(1):9-16
The efficiency of free and alginate-encapsulated Azotobacter chroococcum in fixing nitrogen and their susceptibility to bacteriophages were studied in pure liquid cultures (in vitro) and under cultivated soil conditions (in vivo). Bacteriophages of A. chroococcum were isolated and were found to be common in soil of the Experimental Farm of Fac. Agric., Minia Univ., Egypt. In pure liquid cultures, the immobilized cells exhibited much higher nitrogenase activity (about 57 fold) than the free ones. The encapsulation system offered high protection to A. chroococcum against their phages. No nitrogenase activity was detected for the free cells in presence of phages. Uner cultivated soil conditions, inoculation of maize plants (Zea mays, cv. GIZA 2) with immobilized A. chroococcum, markedly increased rhizosphere and rhizoplane Azotobacter population, significantly increased plant N% as well as dry weight/plant, compared to those inoculated with free cells. In free cells inoculated-plants, bacteriophages had a marked depressive effect on rhizosphere and rhizoplane Azotobacter population, significantly reduced plant N% and dry weight/plant, as compared to plants inoculated with free cells in absence of phages. In plants inoculated with immobilized cells, no significant effect for presence of phages was detected in plant N% and dry weight/plant, whereas, a slight reduction in rhizosphere and rhizoplane Azotobacter population was observed. 相似文献
134.
135.
Hammad Basma Evans Nicholas R. Rudd James H. F. Tawakol Ahmed 《Journal of nuclear cardiology》2017,24(3):938-943
Journal of Nuclear Cardiology - Atherosclerotic diseases account for nearly half of all deaths and are leading causes of adult disability. Our understanding of how atherosclerosis leads to... 相似文献
136.
This study was performed to investigate differences in the shape of the individual palatal rugae in two population samples of Arabian children from Egypt and Saudi Arabia, and develop discriminant function to identify the populations based on rugae shape. A total of 152 stone casts (80 from Egyptian and 72 from Saudi children), equally distributed between genders aged 6–8 years were examined for rugae shape (straight, wavy, curved, circular, unification and cross-link) and their incidence was recorded. Association between rugae shape and gender as well as rugae shape and population were tested using chi-square and discriminant function analyses using SPSS 13 statistical package. Curved and wavy were the most prevalent rugae shape in both groups, followed by straight rugae. Circular, converged and diverged unifications were few in number, while cross-link rugae were not observed in Saudi children. No significant gender differences were observed. Chi-square analysis for association between rugae shape and population groups showed significant differences in curved, wavy, cross-link, converged and diverged unification. Three rugae shapes; wavy, diverging unification and cross-link contributed to the discriminant function which enabled population identification. It was concluded that palatal rugae shape revealed significant differences between the two Egyptian and Saudi populations and also confirmed previous reports of lack of gender dimorphism. Discriminant function analysis allowed differentiation of the populations and it is inferred that discrete variables such as rugae shape are better suited for that purpose than continuous variables such as rugae length. 相似文献
137.
Kool M van Loo G Waelput W De Prijck S Muskens F Sze M van Praet J Branco-Madeira F Janssens S Reizis B Elewaut D Beyaert R Hammad H Lambrecht BN 《Immunity》2011,35(1):82-96
Dendritic cells (DCs) regulate both immunity and tolerance. Here we have shown that the ubiquitin editing enzyme A20 (Tnfaip3) determines the activation threshold of DCs, via control of canonical NF-κB activation. Tnfaip3(fl/fl)Cd11c-cre(+) mice lacking A20 in DCs demonstrated spontaneous proliferation of conventional and double-negative T?cells, their conversion to interferon-γ (IFN-γ)-producing effector cells, and expansion of plasma cells. They developed ds-DNA antibodies, nephritis, the antiphospholipid syndrome, and lymphosplenomegaly-features of systemic lupus erythematosus-and extramedullary hematopoiesis. A20-deficient DCs were resistant to apoptosis, caused by increased sensitivity to CD40L and RANKL prosurvival signals and upregulation of antiapoptotic proteins Bcl-2 and Bcl-x. They captured injected apoptotic cells more efficiently, resisted the inhibitory effects of apoptotic cells, and induced self-reactive effector lymphocytes. Because genetic polymorphisms in TNFAIP3 are associated with human autoimmune disorders, these findings identify A20-mediated control of DC activation as a crucial checkpoint in the development of systemic autoimmunity. 相似文献
138.
Golka K Roemer HC Weistenhöfer W Blaszkewicz M Hammad S Reckwitz T Loehlein D Hartel M Hengstler JG Geller F 《Journal of toxicology and environmental health. Part A》2012,75(8-10):572-581
Apart from genetics, nutrition, and environment, occupational factors also play an important role in colon and rectal cancer development. The aim of this study was to examine these cancer types in an area of former coal, iron, and steel industries, which was found to display an increased incidence of colon cancer mortality. N-Acetyltransferase 2 (NAT2) and glutathione S-transferase M1 (GSTM1) genotypes were investigated in 108 colon cancer cases, 80 rectum cancer cases, and 188 controls (suffering from nonmalignant diseases). Further, in a pilot study, 28 colorectal cancer patients were NAT2 phenotyped by the caffeine test. Possible occupational and nonoccupational risk factors were investigated by a personal interview. The frequency of rapid NAT2 genotype was 35% in colon cancer cases, 47% in rectal cancer cases, and 42% in controls (GSTM1 0/0 genotype: 53, 46, and 47%, respectively). In the 29 patients with cancer in the ascending colon, 10% were of the rapid NAT2 genotype. In the pilot study the frequency of the rapid NAT2 phenotype was 49%. The only major professional group with an elevated risk was painters (colon cancer OR 2.48, 95% CI 0.4-15.23; rectal cancer OR 5.65, 95% CI 1.06-30.21). In contrast to early studies, in the present study the slow NAT2 status is overrepresented. As colorectal cancer is associated with nutrition and physical activity, present findings may be due to excessive physical heavy work and the resulting nutrition in this area. 相似文献
139.
Al-Tonbary Y Al-Hasan SA Zaki M Hammad A Kandil S Fouda A 《Hematology (Amsterdam, Netherlands)》2011,16(1):14-19
This study aimed to evaluate oxidative stress and apoptosis in childhood acute lymphoblastic leukemia (ALL) at diagnosis and their impact on outcome at the end of the induction phase. Our study included 50 newly diagnosed children with ALL. Evaluation of oxidative stresses (malondialdehyde and total anti-oxidant capacity) was made at diagnosis and at the end of the induction phase. Apoptosis level was determined by fluorometric terminal deoxynucleotidyl transferase dUTP nick end labeling system for patients at diagnosis and after 1 week of treatment. Our study showed that there was increased oxidative stress at diagnosis and after treatment with chemotherapy. Apoptosis index was higher after 1 week of treatment with chemotherapy when compared to its level at diagnosis. 相似文献
140.