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2型糖尿病及骨质疏松已成为我国最主要的慢性代谢性疾病。2型糖尿病常伴有血脂紊乱,常表现为低密度脂蛋白升高,而越来越多的研究表明血脂通过不同的方式影响骨代谢,其机制可能是通过抑制骨髓间充质干细胞成骨分化,通过RANK/RNAKL/OPG信号通路及炎症反应调节破骨细胞等方式调节骨代谢。 相似文献
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Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
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目的:分析比较"F"形空心钉与传统倒三角3枚平行螺钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折的临床疗效。方法:2017年1月至2020年1月收治Pauwels Ⅲ型股骨颈骨折患者38例,根据置入钉方式的不同将其分为两组,其中A组18例,采用"F"形空心钉固定,男12例,女6例,年龄37~55岁,受伤至手术时间1~3 d。B组20例,采用传统倒三角3枚平行拉力螺钉固定,男12例,女8例,年龄35~55岁,受伤至手术时间为1~3 d。比较两组患者骨折不愈合,股骨头坏死,股骨颈短缩,空心螺钉退出情况,髋关节功能Harris评分,疼痛视觉模拟评分(visual analogue scale,VAS)。结果:所有患者获得随访,时间为15~31个月。两组患者在骨折不愈合,股骨颈短缩,股骨头坏死方面差异无统计学意义(P>0.05);两组患者在螺钉退出方面差异有统计学意义(P<0.05)。两组患者术后12个月时髋关节Harris评分及VAS评分差异均无统计学差异(P>0.05)。结论:"F"形与传统倒三角3枚平行空心钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折中短期疗效相似,但"F"形空心钉退钉率较低。 相似文献
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《Journal of Medical Imaging and Radiation Sciences》2015,46(4):442-449
The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency. 相似文献
17.
《Biomaterials》2015
In normal tissue repair, macrophages exhibit a pro-inflammatory phenotype (M1) at early stages and a pro-healing phenotype (M2) at later stages. We have previously shown that M1 macrophages initiate angiogenesis while M2 macrophages promote vessel maturation. Therefore, we reasoned that scaffolds that promote sequential M1 and M2 polarization of infiltrating macrophages should result in enhanced angiogenesis and healing. To this end, we first analyzed the in vitro kinetics of macrophage phenotype switch using flow cytometry, gene expression, and cytokine secretion analysis. Then, we designed scaffolds for bone regeneration based on modifications of decellularized bone for a short release of interferon-gamma (IFNg) to promote the M1 phenotype, followed by a more sustained release of interleukin-4 (IL4) to promote the M2 phenotype. To achieve this sequential release profile, IFNg was physically adsorbed onto the scaffolds, while IL4 was attached via biotin-streptavidin binding. Interestingly, despite the strong interactions between biotin and streptavidin, release studies showed that biotinylated IL4 was released over 6 days. These scaffolds promoted sequential M1 and M2 polarization of primary human macrophages as measured by gene expression of ten M1 and M2 markers and secretion of four cytokines, although the overlapping phases of IFNg and IL4 release tempered polarization to some extent. Murine subcutaneous implantation model showed increased vascularization in scaffolds releasing IFNg compared to controls. This study demonstrates that scaffolds for tissue engineering can be designed to harness the angiogenic behavior of host macrophages towards scaffold vascularization. 相似文献
18.
《Clinical Lymphoma, Myeloma & Leukemia》2020,20(7):415-421
Myelofibrosis (MF) is a BCR-ABL1− myeloproliferative neoplasm that arises from hematopoietic stem and progenitor cells frequently harboring a somatic driver mutation in 1 of 3 genes: JAK2, CALR, or MPL. The pathologic features of this hematologic malignancy include myeloproliferation, diffuse bone marrow fibrosis, and overactivation of the JAK-STAT pathway, resulting in enhanced inflammatory cytokine release. The common clinical manifestations of MF include systemic symptoms, abnormal peripheral blood count levels, and splenomegaly. However, it has become increasingly appreciated that significant clinical heterogeneity exists among patients with MF. Two distinct MF clinical phenotypes include the myeloproliferative and myelodepletive phenotype, with peripheral blood counts being the main discerning feature. Patients with the myeloproliferative phenotype will present with elevated peripheral blood counts and often experience significant constitutional symptoms and progressive splenomegaly. In contrast, patients with the myelodepletive phenotype will have low peripheral blood counts and will frequently require transfusion support. Current frontline therapies for MF, include ruxolitinib and fedratinib, which can exacerbate cytopenias and thereby pose an impediment to effective treatment of the myelodepletive patient. The present review discusses the clinical and prognostic implications of the myelodepletive phenotype and the therapeutic options and limitations for this subset of patients, representing an unmet clinical need. 相似文献
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《The Journal of arthroplasty》2022,37(7):1338-1347
BackgroundMultimodal pain therapy combining analgesics, local infiltration analgesia (LIA) and peripheral nerve blocks, such as fascia iliaca compartment block (FICB), can improve postoperative pain, nausea and vomiting (PONV) and ambulation in patients undergoing total hip arthroplasty (THA). We hypothesized that addition of FICB would decrease opioid requirements and length of stay (LOS) but could create a motor block.MethodsThis is a single center, prospective, blinded randomized controlled study of 152 patients undergoing elective THA via direct anterior approach from October 2019 till August 2021. Three patient groups were defined: patients receiving only spinal anesthesia (control group, n = 53); spinal anesthesia with LIA perioperatively (n = 50); and spinal anesthesia with FICB on the recovery unit (n = 49). Outcome measures consisted of postoperative pain scores, PONV, length of hospital stay, opioid requirements and mobility.ResultsOverall pain scores were low for all patient groups, with a lower pain score for LIA in comparison to the control group until 4 hours postoperatively (P < .05). Length of hospital stay, postoperative pain, nausea and vomiting (PONV) scores and quadriceps muscle strength did not differ significantly between groups. The control group showed higher scores at 12 hours postoperatively in comparison to FICB regarding rehabilitation potential, use of walking aids and activities of daily living (P < .05), but all groups reached the same endpoint 48 hours postoperatively. The LIA and FICB groups required less opioids until 24 hours postoperatively.ConclusionLIA is a beneficial adjuvant therapy to spinal anesthesia in THA patients as it may decrease pain scores and the need for opioid consumption. Adjuvant FICB only provided lower opioid requirements. 相似文献