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排序方式: 共有465条查询结果,搜索用时 15 毫秒
21.
Garrahy PJ Dean LS Bulle TM Anderson JC Baxley WA Nath H 《Journal of interventional cardiology》1991,4(3):181-187
This study was performed to evaluate the importance of the duration of balloon inflation during PTCA, by comparing two common inflation durations. Patients were randomized to a 30-second inflation protocol (group I, 83 procedures, 109 lesions), or a 60-second protocol (group II, 83 procedures, 115 lesions). There were no differences in baseline characteristics between the two groups, and no subsequent differences in mean inflation number (3.4 +/- 1.6 vs 3.1 +/- 1.6), residual stenosis (34% +/- 17% vs 33% +/- 16%), presence of dissection (29% vs 34%), or clinical success (89% vs 84%), group I versus group II, respectively. The 30-second inflations caused significantly less chest pain score (147 +/- 239 vs 399 +/- 516, P less than 0.001), and ST segment alteration (75 +/- 94 seconds vs 136 +/- 163, P less than 0.05). These results indicate that 60-second inflations do not produce a superior result to 30-second inflations. Furthermore, shorter inflations are much better tolerated. 相似文献
22.
Association of granulocyte-macrophage colony-stimulating factor with the crystalloid granules of human eosinophils 总被引:3,自引:1,他引:3
Levi-Schaffer F; Lacy P; Severs NJ; Newman TM; North J; Gomperts B; Kay AB; Moqbel R 《Blood》1995,85(9):2579-2586
We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils. 相似文献
23.
24.
Jelinek J; Fairbairn LJ; Dexter TM; Rafferty JA; Stocking C; Ostertag W; Margison GP 《Blood》1996,87(5):1957-1961
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas. 相似文献
25.
手术是脉管性病变治疗的一种手段,其主要作用是与放射治疗及各种药物治疗协同作用。对于血管瘤患者,手术仅限于普萘洛尔治疗无效,出现并发症及位于眼部的病变。整形手术可使血管瘤消退后遗留的面部畸形得到改善。对于一些范围较小的局灶性病变,手术往往可以取得满意的效果;对于巨大、多发的血管瘤,手术治疗往往作用有限,常常为减瘤术。手术患者一般在术前均经过栓塞硬化治疗,这样可以大大减少术中出血。手术无法治愈脉管性疾病,是一种辅助 相似文献
26.
A. Touré D. Cissé KJJO. Kadio A. Camara FA. Traoré A. Delamou S. Sididé C. Kouyaté IS. Bangoura MM. Diallo TM. Tounkara F. Traoré MS. Sow N. Khanafer M. Cissé 《Revue d'épidémiologie et de santé publique》2018,66(4):273-279
Background
Late or inadequate therapeutic management increases the risk of mortality associated with HIV/AIDS. The aim of this study was to analyze the proportion and factors associated with loss of follow-up in HIV patients who receiving antiretroviral therapy at Conakry.Methods
A retrospective cohort study was conducted in HIV patients aged over 15 years and who receiving antiretroviral therapy. Between August 1, 2008 and July 31, 2015, all patients managed by the ambulatory treatment center of the Guinean Women Association against AIDS and sexually and transmissible infection were included. Loss of follow-up was defined as no follow-up visit within 3 months. Kaplan–Meier curves and multivariate Cox regression modelResults
614 patients aged 36.3 ± 11.2 years, mainly females (68.4%) and living in Conakry (80.5%) were included. Among them, 104 were loss to follow-up, corresponding to a proportion rate of 16.9% (95% CI: 14.2–19.7%) or 5.79/100 person-years. The results of multivariate analyses showed that factors independently associated with loss of follow-up were malnutrition (AHR = 7.05; 95% CI: 2.05–24.27; P = 0.002) and CD4 cells account at the initiation of AHR (2.35; 95% CI: 1.61–6.39; P = 0.016) in patients with 201–350 CD4/μL and 5.83 (95% CI: 2.85–11.90; P < 0.001) in patients with less than 150 CD4/μL.Conclusion
Despite efforts of health care workers and free antiretroviral therapy, many patients were loss to follow-up. Multivariate analysis showed that malnutrition and low CD4 account were independently associated with loss to follow-up. 相似文献27.
Justin van Loon Dani l Hoornenborg Inger Sierevelt Kim TM Opdam Gino MMJ Kerkhoffs Dani l Haverkamp 《World journal of orthopedics》2020,11(10):442-452
BACKGROUND Polyethylene(PE) particles produced by wear of the acetabular insert are thought to cause osteolysis and thereby aseptic loosening of the implant in total hip arthroplasty(THA). As highly cross-linked polyethylene(HXLPE) is presumed to give lower wear rates, in vivo studies are needed to confirm this.AIM To compare the wear of REXPOL, a HXPLE, with conventional PE within the first five years after implantation using Roentgen stereophotogrammetric analysis(RSA).METHODS Patients were randomised to receive either a HXLPE(REXPOL) or a conventional PE insert during primary THA. RSA images were obtained directly postoperative and after 6 wk, 12 wk, 6 mo, 12 mo, 24 mo and five years. Functional outcomes were assessed using the Hip Injury and Osteoarthritis Outcome Score and Harris Hip Score at baseline and five years after surgery.RESULTS The HXLPE(REXPOL) showed less wear in the latero-medial direction. Significant wear rates of conventional PE were seen in the latero-medial and center-proximal direction and in volume and corrected volume, whereas the REXPOL did not show these outcomes over time. Improvement from baseline in functional outcome did not significantly differ.CONCLUSION Total 3 D wear is less in THAs inserted with a REXPOL inlay than a conventional PE inlay after five years. This study confirms, for the first, that the REXPOL HXLPE inlay is preferred to standard PE. 相似文献
28.
Marsh JC; Will AJ; Hows JM; Sartori P; Darbyshire PJ; Williamson PJ; Oscier DG; Dexter TM; Testa NG 《Blood》1992,79(12):3138-3144
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse. 相似文献
29.
CALLA-positive myeloma: an aggressive subtype with poor survival 总被引:5,自引:0,他引:5
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group. 相似文献
30.
Anniek KD Visser Nisha K Ramakrishnan Antoon TM Willemsen Valentina Di Gialleonardo Erik FJ de Vries Ido P Kema Rudi AJO Dierckx Aren van Waarde 《Journal of cerebral blood flow and metabolism》2014,34(1):118-125
The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents. 相似文献