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51.
Murine side population (SP) cells may have an increased ability to engraft lethally irradiated mice and lack CD34 expression. Strategies using CD34 as a primary marker of haemopoietic stem cells may therefore result in the exclusion of a primitive stem cell population. The molecular basis for the murine SP phenotype has been attributed to the multidrug-resistance transporter ABCG2. This study aimed to investigate ABCG2 expression from a variety of human sources and investigate the relationship between ABCG2 expression, the SP phenotype, and expression of markers such as CD34 and CD133. SP cells were observed in different haemopoietic sources, but a significant increase in the number of SP cells was observed in PB following granulocyte colony-stimulating factor mobilisation. No direct correlation between the frequency of SP cells and the expression of ABCG2 was observed. SP cells were identified in both lineage-positive and lineage-negative population and ABCG2 expression was enriched in lineage-negative SP cells. Lineage-negative SP cells were devoid of CD34 expression but enriched for CD133. Subsequent analysis revealed that ABCG2 and CD133 are coexpressed. Together, these data suggest that the ABCG2 transporter is neither required nor responsible for the SP phenotpye in many human blood cells. 相似文献
52.
S K Bansal U K Dhand N Khandelwal J S Chopra 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1990,58(4):717-719
Leprous mononeuropathy may present without demonstrable maculoanesthetical patches. A case is described in whom wasting of the right hand was initially attributed to C8 T1 entrapment radiculopathy caused by cervical perineurial cysts. On the basis of the benign nature of the perineurial cysts and questionable right ulnar nerve thickening, the patient was given a trial of anti-leprosy drugs. A follow-up clinico-electrophysiological evaluation favored the diagnosis of leprotic ulnar mononeuropathy. 相似文献
53.
Jean-François Timsit Mark Rupp Emilio Bouza Vineet Chopra Tarja Kärpänen Kevin Laupland Thiago Lisboa Leonard Mermel Olivier Mimoz Jean-Jacques Parienti Garyphalia Poulakou Bertrand Souweine Walter Zingg 《Intensive care medicine》2018,44(6):742-759
Intravascular catheters are inserted into almost all critically ill patients. This review provides up-to-date insight into available knowledge on epidemiology and diagnosis of complications of central vein and arterial catheters in ICU. It discusses the optimal therapy of catheter-related infections and thrombosis. Prevention of complications is a multidisciplinary task that combines both improvement of the process of care and introduction of new technologies. We emphasize the main component of the prevention strategies that should be used in critical care and propose areas of future investigation in this field. 相似文献
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56.
Arora Shiyana Dharavath Ravinder Naik Bansal Yashika Bishnoi Mahendra Kondepudi Kanthi Kiran Chopra Kanwaljit 《Metabolic brain disease》2021,36(6):1315-1330
Metabolic Brain Disease - The night shift paradigm induces a state of chronic partial sleep deprivation (CPSD) and enhances the vulnerability to neuronal dysfunction. However, the specific neuronal... 相似文献
57.
Primary gallbladder cancer: recognition of risk factors and the role of prophylactic cholecystectomy 总被引:8,自引:0,他引:8
The objective of this article is to review the available literature on the epidemiology, predisposing factors, and conditions associated with primary gallbladder cancer, and to discuss the role of prophylactic cholecystectomy in high-risk patient populations. Gallbladder cancer is a highly malignant tumor with a poor 5-yr-survival rate. It is a tumor of the elderly and has striking genetic, racial, and geographic characteristics, with an extremely high prevalence in Native Americans and Chileans. Cholelithiasis is a well-established risk factor for gallbladder cancer and the risk seems to correlate with stone size. Polyps that are >1 cm, single, sessile, and echopenic are associated with a higher risk of malignancy. Anomalous junction of pancreaticobiliary ducts (AJPBD), especially without choledochal cyst, and porcelain gallbladder are additional factors that predispose to gallbladder cancer. Lesser associations include chronic bacterial infections of the gallbladder, typhoid carrier state, certain occupational and environmental carcinogens, hormonal changes in women, and certain social, dietary, and familial factors. It is important to identify high-risk groups for gallbladder cancer because of the dismal nature of this tumor. In patients with porcelain gallbladder and anomalous junction of the pancreatic and biliary ducts, cholecystectomy is recommended provided that the patient is a good operative candidate. Patients with large solitary polyps or gallstones require close ultrasonic follow-up. With the advent of endoscopic ultrasound it is expected that early changes of malignancy in polyps will be reliably detected, and more patients will potentially be cured with a simple cholecystectomy. Through a MEDLINE/PAPERCHASE search we identified and reviewed articles regarding gallbladder cancer published in English-language journals between 1966 and 1999, using the key words biliary tract and gallbladder diseases, cancer, neoplasms, surgery, cholelithiasis, gallstones, cholecystitis, gallbladder polyps, risk factors, chemical industry, occupational diseases, typhoid, porcelain gallbladder, bacteremia, and precancerous conditions. We also used the bibliography of relevant articles to increase our search. A total of 122 publications were selected using the mentioned data source. 相似文献
58.
Radiofrequency ablation is the treatment of choice for patients with Wolff-Parkinson-White syndrome and symptomatic tachyarrhythmias. The technique involves localising the pathway with multiple catheters at various sites followed by radiofrequency energy application at that site. Single catheter approach has been described for ablation of manifest left-sided accessory pathways. In this article, we report the ablation of accessory pathways in different locations in patients with Wolff-Parkinson-White syndrome by using a two-catheter approach. Twenty-three consecutive patients with symptomatic Wolff-Parkinson-White syndrome were taken up for radiofrequency ablation with this approach. Pathways could be successfully ablated in 11 out of 13 patients with left free wall, 5 out of 7 with right posteroseptal, one patient of left posteroseptal and each of the 2 patients of right mid septal locations giving an overall success in 19/23 (82.6%) patients. Hence, two-catheter approach can be used safely to ablate accessory pathways in different locations with high success rate, thus minimising the procedure time associated with conventional approach. 相似文献
59.
Methotrexate (MTX) is among the best-tolerated disease-modifying antirheumatic drugs for the treatment of rheumatoid arthritis (RA); major drawbacks of MTX therapy are the large interpatient variability in clinical response and the unpredictable appearance of a large spectrum of side effects. Several studies have demonstrated gene polymorphism that may regulate intracellular methotrexate metabolic pathway enzymes linked to drug efficacy and safety, but the evidence available is not yet conclusive. We decided to run a pilot study to determine the incidence of Methylene tetrahydrofolate (MTHFR; C677T, A1298C) and Thymidylate synthase (TS; 5′ UTR repeat, 3′ UTR deletion) gene polymorphism in rheumatoid arthritis patients in our community (Indian Asian) and further explore its association with MTX response (efficacy, toxicity). Thirty-four naïve RA patients on supervised MTX therapy and 139 healthy controls were genotyped for A1298C and C677T polymorphism of the MTHFR gene and 5′ UTR repeat and 3′ UTR deletion polymorphism of the TYMS gene by polymerase chain reaction-restriction fragment length polymorphism. Association, if any, between gene polymorphism and MTX response in RA patients was analyzed. The MTHFR A1298C ‘C’ allele incidence among RA patients (46%) was significantly higher (χ 2?=?4.24, P?0.05, OR?=?1.68). None of the other allele tested showed any association. Although a small sample study, our findings do not suggest a significant association of MTHFR/TS allele/genotype with MTX response in our ethnically distinct Indian (Asian) RA patients. 相似文献
60.
BACKGROUND: An attempt was made to induce aortoarteritis in mice by using various antigens. METHODS AND RESULTS: The Swiss mice were immunized with eight different antigens and were grouped A to G. Group H served as control. The mice were then bled at 1st, 2nd, 4th, 6th and 8th month interval post-immunization for estimating antibody titer. Then the mice were sacrificed and the heart, aorta and kidney were taken out and processed for hematoxylin-eosin staining. There was gradual increase in the antibody titer from 1st month till 4th month within all the experimental groups (A-G), when compared with control group H. The titer started falling sharply from 6th month post-immunization. However, the control group H did not show much variation. When each individual group was compared separately with control group H, the significant statistical value was obtained. Histopathological examination revealed mild inflammation (+) in kidney by 2nd month, moderate inflammation (++) by 6th month, extensive inflammation (+++) by 8th month and alteration in the normal parenchyma of kidney by 8th month. CONCLUSIONS: The histopathological changes brought out through antigens were more pronounced by 8th month following injection of tunica media, tunica adventitia, tunica intima and aorta collagen as compared to that of standard collagen and mouse aorta injections. 相似文献