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排序方式: 共有374条查询结果,搜索用时 15 毫秒
1.
Vascular Endothelial Growth Factor Expression and Cyclosporine Toxicity in Renal Allograft Rejection 总被引:3,自引:0,他引:3
B. Handan Özdemir F. Nurhan Özdemir Nihan Haberal Remzi Emiroglu Beyhan Demirhan Mehmet Haberal 《American journal of transplantation》2005,5(4):766-774
The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term. 相似文献
2.
Dr. Bektaş Açikgöz Mehmet Turgut Osman Ekin Özcan Tunçalp Özgen Beyhan Demirhan Şevket Ruacan 《Lasers in medical science》1992,7(1-4):49-53
In this study we have investigated the negative influence of CO2 and Nd-YAG laser irradiation on rapid cranial regeneration and whether it has any use in certain types of craniosynostosis.
Twenty-two newborn rats were used in the study. Both CO2 and Nd-YAG laser irradiation, which was applied to free bony edges after, suturectomies, resulted in a significant decrease
in skull regeneration. Histopathological examinations revealed severe degeneration caused by both types of laser energies. 相似文献
3.
Jordan C. Best BS Taylor Kohn MD Premal Patel MD Ruben Blachman-Braun MD Elaine de Quadros PhD Zeki Beyhan PhD Michael Jacobs MD Ranjith Ramasamy MD 《Andrologia》2021,53(7):e14094
In this study, we sought to determine whether sperm DNA fragmentation (DFI%) and high DNA stainability (HDS%) evaluated by sperm chromatin structure assay (SCSA) predict recurrent implantation failure (RIF) or pregnancy rate. A retrospective study was performed of consecutive cycles of ICSI treatment from 2009 to 2018. A total of 386 couples that underwent 1,216 frozen embryo transfer (FET) cycles were analysed. Mean female and male age was 34 ± 3.6 years and 37.3 ± 6.6 years, respectively, and a median total motile sperm count (TMSC) was 43.5 [9.9–105.5] million. Overall median DFI% and HDS% was 12 [7.1–18.9] and 9.6 [6.5–14.4] respectively. On multivariable analysis, DFI% and HDS% were not associated with RIF (DFI%: OR = 1.01, 95% CI: 0.98–1.04, p = .414; HDS%: OR = 0.97, 95% CI: 0.94–1.01, p = .107) or IVF success, defined as clinical pregnancy (DFI%: OR = 1.00, 95% CI: 0.99–1.01, p = .641; HDS%: OR = 1.01, 95% CI: 0.99–1.02, p = .565). We found that neither DFI% or HDS%, as assessed by SCSA, were predictive of RIF or pregnancy rate. This finding suggests that sperm DNA fragmentation does not predict RIF or pregnancy rate. 相似文献
4.
5.
Mufide Oncel Seval Akbulut Turkan Toka Ozer Aysel Kiyici Mustafa Keles Beyhan Baltaci 《Renal failure》2016,38(7):1071-1075
Background: Cytokines are essential mediators of immune response. Chronic renal failure patients suffer from chronic inflammation that results from factors such as impaired renal function, accumulation of uremic toxins and bio incompatibility of dialyzer membranes. These patients are also at increased risk of cardiovascular diseases. We have evaluated cytokines, adipocytokines and inflammatory markers in patients with chronic renal failure undergoing hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD).Material and methods: We have determined serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP), leptin and ghrelin levels of chronic renal failure patients treated with either HD (n?=?20) or CAPD (n?=?20). TNF-α, IL-6, ghrelin and leptin measurements were performed by commercially available kits based on enzyme-linked immunosorbent assay (ELISA) method. hsCRP levels were determined by turbidimetric methods.Results: Serum TNF-α and IL-6 levels of patients on HD were significantly higher than those of the ones on CAPD (p?<?0.05). Ghrelin, leptin and hsCRP concentrations were similar in both groups.Conclusions: We can conclude that cytokine production is more obvious in HD process. 相似文献
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7.
Salivary gland tumors (SGTs) make up a small portion (approximately 5%) of all head and neck tumors. Most of them are located in the parotid glands, while they are less frequently located in the submandibular glands, minor salivary glands or sublingual gland. The incidence of malignant or benign tumors (BTs) in the salivary glands varies according to the salivary gland from which they originate. While most of those detected in the parotid gland tend to be benign, the incidence of malignancy increases in other glands. The use of magnetic resonance imaging (MRI) in the diagnosis of SGTs is increasing every day. While conventional sequences provide sufficient data on the presence, localization, extent and number of the tumor, they are insufficient for tumor specification. With the widespread use of advanced techniques such as diffusion-weighted imaging, semi-quantitative and quantitative perfusion MRI, studies and data have been published on the differentiation of malignant or BTs and the specificity of their subtypes. With diffusion MRI, differentiation can be made by utilizing the cellularity and microstructural properties of tumors. For example, SGTs such as high cellular Warthin’s tumor (WT) or lymphoma on diffusion MRI have been reported to have significantly lower apparent diffusion values than other tumors. Contrast agent uptake and wash-out levels of tumors can be detected with semi-quantitative perfusion MRI. For example, it is reported that almost all of the pleomorphic adenomas show an increasing enhancement time intensity curve and do not wash-out. On quantitative perfusion MRI studies using perfusion parameters such as Ktrans, Kep, and Ve, it is reported that WTs can show higher Kep and lower Ve values than other tumors. In this study, the contribution of advanced MRI to the diagnosis and differential diagnosis of SGTs will be reviewed. 相似文献
8.
Fran?oise Fichaux Jocelyne Marchand Beyhan Yaylali Viviane Heelercq-Meyer Jacqueline Catala Willy J. Malaisse 《Journal of gastrointestinal cancer》1991,8(2):151-167
Ligation of the pancreatic duct in rabbits provokes a decrease in the insulin and glucagon content of the pancreas, and may
lead to chronic hyperglycemia. The insulin secretory behavior of the perfused pancreas is perturbed in duct-ligated animals,
and this is illustrated in several respects:
The perturbation of the anomeric specificity in secretory response is most obvious in diabetic duct-ligated rabbits, in which
case β-D-glucose stimulates insulin release more efficiently than α-D-glucose. In both control and duct-ligated rabbits, however,
the α-anomer is more potent than the β-anomer in suppressing leucine-stimulated glucagon secretion. These findings are compatible
with the view that chronic hyperglycemia leads to alteration in the anomeric preference of the pancreatic B-cell for α-D-glucose,
possibly as a result of the nonenzymatic glycation of glycolytic enzymes in insulin-producing, but not glucagon-producing,
islet cells. 相似文献
1. | The steady-state insulin output evoked by L-leucine (10mM) is higher in duct-ligated than control rabbits; |
2. | In the presence of the amino acid, the response to D-glucose is characterized by a delayed onset, the absence of an early secretory peak, and a sluggish return towards basal value upon removal of the hexose from the perfusate; and |
3. | Whereas control rabbits display a higher secretory response to α - than β-D-glucose, such is no more the case in duct-ligated rabbits. |
9.
10.
Bülent Tutluoglu Cigdem Bayram Gurel Sule Beyhan Ozdas Benan Musellim Serdar Erturan A Nihat Anakkaya Günseli Kilinc Turgut Ulutin 《Clinical and applied thrombosis/hemostasis》2005,11(1):77-81
Platelets have the capacity to release mediators with potent inflammatory or anaphylactic properties. Platelet factor-4 (PF4) and beta-thromboglobulin (BTG) are two of these mediators. On the other hand, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) are two important mediators of fibrinolysis. Both mediators are secreted mainly by vascular endothelium. Plasma levels of PF4, BTG, PAI-1, and tPA may show changes in chronic inflammatory diseases such as asthma. This study examined the role of thrombocytes and the function of the endothelium in asthmatic patients during an attack and during a stable phase. Eighteen patients with known allergic asthma who came to our emergency department with an asthma attack and 14 control subjects were included in the study. Blood samples were taken after starting therapy with salbutamol inhalation. Lung function tests were performed after receiving the first emergency therapy for asthma. Plasma levels of PF4, BTG, PAI-1, tPA were determined before starting steroid therapy and after receiving 1 week of steroid therapy. Plasma levels of PF4 among patients with an asthma attack were significantly higher than those of controls (150.5+/-8.92 IU/mL vs. 92.5+/-7.63 IU/mL, p<0.001). A further increase in plasma PF4 levels was detected after steroid therapy (163.5+/-9.16 IU/mL). Plasma BTG levels of patients on admission were not statistically different from those in the control group (140.4+/-6.34 IU/mL vs. 152.2+/-8.71 IU/mL). An increase was detected after therapy (171.6+/-7.27 IU/mL) and post-treatment plasma levels were statistically meaningful versus the controls. Plasma levels of tPA and PAI were statistically higher than those in controls in asthmatic patients on admission (6.01+/-2.72 vs. 5.4+/-2.3 ng/mL for tPA and 75.2+/-27.2 ng/mL vs. 32.7+/-14.3 ng/mL for PAI-1). Further increases were detected in two parameters after 1 week of therapy with steroids (tPA levels were 6.85+/-2.96 ng/mL and PAI-1 levels were 83.5+/-29.6 ng/mL). There seems to be an increased activity of platelets during an asthma attack. Elevated PAI-1 and tPA levels may also indicate the activated endothelium in asthma. Increases of plasma levels of PAI-1 and tPA after steroid therapy need further investigation because elevated PAI-1 levels enhance airway remodeling. 相似文献