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51.
Thrombopoietin (TPO) or MpI ligand is known to stimulate megakaryocyte (MK) proliferation and differentiation. To identify the earliest human hematopoietic cells on which TPO acts, we cultured single CD34+Thy- 1+Lin- adult bone marrow cells in the presence of TPO alone, with TPO and interleukin-3 (IL-3), or with TPO and c-kit ligand (KL) in the presence of a murine stromal cell line (Sys1). Two distinct growth morphologies were observed: expansion of up to 200 blast cells with subsequent differentiation to large refractile CD41b+ MKs within 3 weeks or expansion to 200-10,000 blast cells, up to 25% of which expressed CD34. The latter blast cell expansions occurred over a 3- to 6-week period without obvious MK differentiation. Morphological staining, analysis of surface marker expression, and colony formation analysis revealed that these populations consisted predominantly of cells committed to the myelomonocytic lineage. The addition of IL-3 to TPO-containing cultures increased the extent of proliferation of single cells, whereas addition of KL increased the percentage of CD34+ cells among the expanding cell populations. Production of multiple colony- forming unit-MK from single CD34+Thy-1+Lin- cells in the presence of TPO was also demonstrated. In limiting dilution assays of CD34+Lin- cells, TPO was found to increase the size and frequency of cobblestone areas at 4 weeks in stromal cultures in the presence of leukemia inhibitory factor and IL-6. In stroma-free cultures, TPO activated a quiescent CD34+Lin-Rhodamine 123lo subset of primitive hematopoietic progenitor cells into cycle, without loss of CD34 expression. These data demonstrate that TPO acts directly on and supports division of cells more primitive than those committed to the MK lineage. 相似文献
52.
Serdar Polat Fatma Cebe Alir?za Tun?demir Caner ?ztürk Asl?han ü?ümez 《The journal of advanced prosthodontics》2015,7(2):108-114
PURPOSE
The aim of this study was to evaluate effect of different surface treatment methods on the bond strength between aged composite-resin core and luting agent.MATERIALS AND METHODS
Seventy-five resin composites and also seventy-five zirconia ceramic discs were prepared. 60 composite samples were exposed to thermal aging (10,000 cycles, 5 to 55℃) and different surface treatment. All specimens were separated into 5 groups (n=15): 1) Intact specimens 2) Thermal aging-air polishing 3) Thermal aging- Er:YAG laser irradiation 4) Thermal aging- acid etching 5) Thermal-aging. All specimens were bonded to the zirconia discs with resin cement and fixed to universal testing machine and bond strength testing loaded to failure with a crosshead speed of 0.5 mm/min. The fractured surface was classified as adhesive failure, cohesive failure and adhesive-cohesive failure. The bond strength data was statistically compared by the Kruskal-Wallis method complemented by the Bonferroni correction Mann-Whitney U test. The probability level for statistical significance was set at α=.05.RESULTS
Thermal aging and different surface treatment methods have significant effect on the bond strength between composite-resin cores and luting-agent (P<.05). The mean baseline bond strength values ranged between 7.07 ± 2.11 and 26.05 ± 6.53 N. The highest bond strength of 26.05 ± 6.53 N was obtained with Group 3. Group 5 showed the lowest value of bond strength.CONCLUSION
Appropriate surface treatment method should be applied to aged composite resin cores or aged-composites restorations should be replaced for the optimal bond strength and the clinical success. 相似文献53.
目的了解O- GIcNAc转移酶(O- GlcNAc transferase,OGT)在直肠癌中的表达情况及对预后的影响。方法利用免疫组化技术,在直肠癌组织芯片上染色OGT,确定表达情况,并与患者临床资料结合,了解OGT的表达与直肠癌患者的生存是否有差异。结果 OGT在直肠癌组织中的表达情况:“-”12.22%、“+”27.78%、“++”44.44%、“+++”15.56%,癌旁组织中的表达情况:“-”18.89%、“+”42.22%、“++”37.78%、“+++”1.11%;癌组织中OGT高表达(++和+++)为60.00%,高于癌旁组织中OGT高标的量38.89%;OGT高表达直肠癌患者的3年生存率分别是82.90%和60.00%,两者比较有统计学差异(字2=7.452,P=0.006)。结论OGT在直肠癌中的表达高于周围正常组织,直肠癌中高表达的3年生存率较低,OGT可能参加了肿瘤的发生、发展过程。 相似文献
54.
Nowadays because of lots of reasons, lifespan is increasing and caregiving of aged people becomes more and more important. Today it is understood how the professional care of aged people is significant, instead of being carried out by volunteers. Because of this, in this study we aimed to understand the problems, and thoughts of aging of caregivers who are working in nursing homes. This study was made using the so-called qualitative research, which is one of the research designs. Including general aim, interviews with 13 caregivers with structured questions, supported by spontaneous ones. Interviews were taped and transcribed verbatim. After that, they were grouped with the same themes. Thoughts are grouped with three main themes, which are about "aging", "working life", "caregiving of aged people". Aged people are described like people who are dependent, need interest, and represent the wisdom period. Also caregiving is described like both good job and punishment. Besides, the reason of working as a caregiver, is the economic needs. The suggestions of caregivers are increasing payment, giving psychological and emotional support, and also improving physical conditions. Economic satisfaction of caregivers, giving psychological support, caregivers with aged people and improving physical conditions are important to increase the quality of professional caregiving. 相似文献
55.
Erhan Özcan Ali Riza Çetin İsmail Davut Çapar Ali Riza Tunçdemir Hale Ari Aydinbelge 《Odontology / the Society of the Nippon Dental University》2013,101(2):204-209
This study evaluated the influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents. Seventy-two extracted maxillary single-rooted canine teeth were randomly divided into two groups of 36 teeth. Group 1, the control group, was filled with gutta-percha only (i.e., did not receive eugenol), whereas group 2 was filled with a eugenol-containing sealer. All root canals were filled and each group was divided into three subgroups. The posts in each subgroup were cemented with the following materials: subgroup 1 with a 2-step self-etching adhesive system (Clearfil Liner Bond 2V + Panavia F); subgroup 2 with a 1-step self-etching adhesive (Panavia F); and subgroup 3 with a self-adhesive (Clearfil SA Cement). Dislodgement resistance was measured using a universal testing machine. All data were subjected to ANOVA using a factorial design and Tukey test (α = 0.05). The use of the eugenol-containing sealer significantly reduced the push-out bond strength of the fiber post (P < 0.05). The push-out bond strength of Panavia F was significantly higher than those of the other groups filled with the eugenol-containing sealer (P < 0.05). The Panavia F group was less susceptible to the inhibiting effect of eugenol than were the other evaluated groups when the fiber post was cemented in the canals filled with the eugenol-containing sealer. 相似文献
56.
The objective of this study was to determine extent of HIV conspiracy belief endorsement among men who have sex with men (MSM) in Pretoria, and assess whether endorsement of HIV conspiracy beliefs are associated with inconsistent condom use and never testing for HIV. A cross-sectional survey using respondent-driven sampling was conducted between February and August 2009. A high proportion of respondents endorsed HIV conspiracy beliefs. MSM commonly endorsed beliefs related to AIDS information being held back from the general public (51.0%), HIV being a man-made virus (25.5%), and people being used as guinea pigs in HIV research and with HIV treatments (approximately 20%). Bisexually- or heterosexually-identified MSM were significantly more likely to endorse conspiracy beliefs compared to homosexually-identified MSM (38.5% vs. 14.7%). Endorsing conspiracy beliefs was not associated with unprotected anal intercourse; however, it was significantly associated with not having been HIV tested (AOR: 2.4; 95% CI: 1.1-5.7). Endorsing beliefs in HIV conspiracies reflects a mistrust in government institutions and systems which could be an impediment to seeking HIV-related services, including HIV counseling and testing. 相似文献
57.
Yıldırım Yusuf Akbaş Yusuf Berk Tunç Uğur Kepez Yıldız Burçin Er Mehmet Onur Demirok Ahmet 《International ophthalmology》2021,41(6):2149-2156
International Ophthalmology - To evaluate long-term visual and refractive outcomes of corneal wavefront-guided transepithelial photorefractive keratectomy (t-PRK) with mitomycin C for the treatment... 相似文献
58.
Tun Hing Lui 《The Journal of foot and ankle surgery》2013,52(1):128-131
Polydactyly of the foot is a congenital anomaly characterized by the appearance of all or part of 1 or more additional rays. The patient with this condition might complain of an abnormal cosmetic appearance or difficulty with footwear. A minimally invasive technique for correction of postaxial metatarsal polydactyly of the foot is presented in this techniques report. 相似文献
59.
Tun Hing Lui 《The Journal of foot and ankle surgery》2013,52(4):529-532
A subchondral cyst of the talus frequently occurs with an osteochondral lesion of the talar dome. Debridement, curettage, and bone grafting through the articular defect was frequently the recommended treatment in reported studies for a massive cyst. We report a case of a massive cyst of the talar body with a small osteochondral lesion of the talar dome. Our patient was successfully treated by curettage and bone grafting of the cyst using posterior ankle arthroscopy, with minimal disruption of the articular surface of the talar dome. 相似文献
60.
Maggie KM Ma Desmond YH Yap Terence PS Yip Sing Leung Lui Wai Kei Lo 《Nephrology (Carlton, Vic.)》2013,18(5):365-368
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture. 相似文献