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71.
Annals of Nuclear Medicine - This study aimed to determine the optimal β value of the relaxation control parameter and the post-smoothing filter in the list-mode dynamic row-action maximum...  相似文献   
72.
2'-Deoxycoformycin (dCF) as a single agent has been reported to be less effective against myeloid than against lymphoid malignancies in clinical trials. However, previous studies have shown that in the presence of 2'-deoxyadenosine (dAd), human monocytoid leukemia cell lines are much more sensitive to dCF with regard to the inhibition of cell proliferation. Thus, dCF might be useful for treating monocytoid leukemia with the aid of dAd analogs. The antiproliferative effects of dCF in combination with dAd or its derivatives were examined on normal and malignant blood and bone marrow cells. In the presence of 10 micromol/L dAd, the concentration of dCF required to inhibit the viability of primary monocytoid leukemia cells was much lower than that required to inhibit normal or non-monocytoid leukemic cells. Among the dAd analogs, 9-beta-D-arabinofuranosyladenine (AraA) was also effective in combination with dCF. Athymic nude mice were inoculated with human monocytoid leukemia U937 cells and treated with dCF or a dAd analog or both. Although dCF alone slightly but significantly prolonged the survival of mice inoculated with U937 cells, combined treatment with dCF and AraA markedly prolonged their survival. These data suggest that the combination of dCF and AraA may be useful for the clinical treatment of acute monocytic leukemia. (Blood. 2000;96:1512-1516)  相似文献   
73.
Udden  MM; Umeda  M; Hirano  Y; Marcus  DM 《Blood》1987,69(1):52-57
The In(Lu) phenotype is inherited as an autosomal dominant trait and is characterized by suppression of the Lutheran, P1, i, and Aua erythrocyte blood group antigens. We have developed a monoclonal antibody (L21) that strongly agglutinates all erythrocytes except In(Lu), and we have identified eight In(Lu) individuals among 42,000 blood donors tested. Studies of two families confirmed the dominant mode of inheritance and revealed several new features of this phenotype. The erythrocytes of all five affected individuals from the two families exhibited diminished hemagglutination by the lectin concanavalin A, although they reacted normally with several other lectins. The erythrocytes of two affected individuals in one family exhibited marked acanthocytosis. The erythrocytes of the proposita of the other family exhibited a mild degree of poikilocytosis, but the cells of the other two affected individuals in this family had normal morphology. The osmotic fragility of fresh In(Lu) erythrocytes was normal, but after incubation for 24 hours at 37 degrees C in plasma the In(Lu) cells exhibited a marked increase in resistance to osmotic lysis. During the incubation period the erythrocytes lost K+ and their total cation content was diminished. These data indicate that in addition to the suppression of blood group antigens noted previously, the In(Lu) phenotype includes a variety of morphological abnormalities and a defect in electrolyte metabolism. The use of L21 and similar monoclonal antibodies provides a more sensitive means of detecting In(Lu) erythrocytes than typing with human anti-Lub antisera.  相似文献   
74.
Background:   Aging is associated with a declining glucose tolerance, which is primarily caused by peripheral insulin resistance, and with a decline in physical activity. The aim of this study was to assess the effect of aerobic and resistance exercise training on insulin action in the elderly.
Methods:   Fourteen healthy male subjects (age: 65–73 years) were enrolled and divided into two exercise groups: resistance training (RT) or a combined aerobic and resistance training (CT). Subjects participated in each training program three times a week for 12 weeks. Before and after the training program, insulin action was determined using the euglycemic clamp technique at insulin infusion rates of 40 (low) or 400 (high) mU/m2 per min. Body composition was measured by dual-energy X-ray absorptiometry (DXA).
Results:   Percent fat decreased significantly in both groups. Fat-free mass (FFM) tended to increase in the RT group ( P  = 0.054), but not in the CT group. In the CT group, the glucose infusion rate (GIR) increased 16.6% ( P  < 0.05) at the low insulin infusion rate and 21.7% ( P  < 0.01) at the high rate. In the RT group, GIR tended to increase at the low insulin infusion rate, but was not statistically significant ( P  = 0.052) and increased 9.9% ( P  < 0.05) at the high rate. When calculated per FFM, the increased insulin action persisted in the CT group ( P  < 0.01), but not in the RT group.
Conclusion:   The combination of aerobic and resistance training is more effective for improving the decreased insulin action in the elderly than resistance training alone.  相似文献   
75.
76.
Background: Titanium (Ti) dental implants have been widely used for prosthetic reconstruction of dentition. Unfortunately, peri‐implantitis can result in failure of dental implant osseointegration. Lipopolysaccharide (LPS) acts as a chronic inflammatory stimulus and maintains peri‐implant inflammation, worsening the prognosis for implant osseointegration. The purpose of this study is to determine the effects of 10 M NaOH‐modified Ti surface with nanonetwork structure on the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMMSCs) in the context of Porphyromonas gingivalis LPS exposure. Methods: Titanium disks treated with 10 M NaOH solution and control were incubated with BMMSCs and exposed to P. gingivalis LPS (0, 0.1, or 1 μg/mL). The effects of the modified nanonetwork structure on osteogenic differentiation of rat BMMSCs were evaluated in the context of different concentrations of P. gingivalis LPS exposure. Results: Rat BMMSCs on the 10 M NaOH‐modified Ti surface with nanonetwork structure had higher levels of osteogenesis‐related gene expression and significantly greater cell proliferation, alkaline phosphatase activity, and extracellular matrix deposition and mineralization than cells on the untreated Ti surfaces, in all the groups with different doses of P. gingivalis LPS exposure. Conclusion: The 10 M NaOH‐modified Ti surface with nanonetwork structure has better endotoxin tolerance under P. gingivalis LPS exposure than the non‐modified surface.  相似文献   
77.
[Purpose] This study investigated the association between the weight-bearing ratio (WBR) and gait ability of a paretic lower limb while walking using a shoe-type load-measuring apparatus. [Subjects] The Subjects comprised 17 stroke patients who were classified into the following two groups: the independent walking group, and the non-independent walking group. [Methods] The 10-m walking time (inside and outside parallel bars) and the Berg Balance Scale (BBS) were measured. The WBR of the paretic lower limb was measured during static standing and while walking inside and outside parallel bars, and the coefficient of variation (CV) was calculated. WBR was evaluated using the Step Aid. [Results] The BBS and WBR were significantly decreased in the non-independent walking group, while the 10-m walking time and the CV were significantly increased in the non-independent walking group. [Conclusion] The CV and WBR of a paretic lower limb while walking appear to be important indices of achievement of independent gait in hemiplegic stroke patients, and they may be used in gait rehabilitation for diseases requiring weight-bearing training to follow the course of training using a shoe-type load-measuring apparatus.Key words: Stroke, Weight-bearing ratio, Shoe-type load-measuring apparatus  相似文献   
78.
79.
Although Helicobacter pylori is classified as a definite carcinogen, the mechanism underlying gastric carcinogenesis is not yet clear. We previously have shown that H. pylori activates an antiapoptotic gene, the cellular inhibitor of apoptosis protein 2 (c-IAP2), the underlying mechanism of which was investigated in the present study. cDNA array and real-time PCR analyses indicated that H. pylori showed a stimulatory effect on the expression of c-IAP2. Isogenic mutant strains with impaired cag pathogenicity island (cagPAI) expression showed weaker induction. Analyses that used the in situ terminal deoxynucleotide transferase-mediated dUTP nick end-labeling method indicated suppression of antiapoptosis by the antisense c-IAP2 oligonucleotide. Reporter assays with deletion and mutation constructs for the c-IAP2 promoter showed that nuclear factor-kappaB (NF-kappaB) binding sites are indispensable for transactivation. Super-repressor IkappaBalpha or NF-kappaB inhibitor reduced c-IAP2 transactivation by H. pylori, and exogenous expression of c-IAP2 inhibited apoptosis seen with H. pylori. In conclusion, H. pylori induces antiapoptosis through c-IAP2 transactivation following cagPAI-dependent NF-kappaB activation. The interaction of these stimuli may play a role in gastric carcinogenesis.  相似文献   
80.
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