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941.
背景:后交叉韧带对人膝关节结构的稳定以及功能的发挥起着重要作用。与内侧副韧带相比,损伤后的后交叉韧带难以很好的自我愈合,甚至会导致半月板撕裂和软骨损伤。为了提高后交叉韧带的愈合能力,这就需要寻找新的途径来再生和修复损伤的后交叉韧带。近年来的研究表明,赖氨酰氧化酶在组织损伤修复过程中起到非常重要的作用,但其在后交叉韧带修复过程中的分子机制研究尚未涉猎。 目的:观察与滑膜细胞共培养后交叉韧带成纤维细胞中赖氨酰氧化酶基因的表达。 方法:将第4代的后交叉韧带成纤维细胞和滑膜细胞分别种植于6孔板和Tanswell中。实验分为2组,即后交叉韧带成纤维细胞与滑膜细胞共培养组和后交叉韧带成纤维细胞单层培养组。培养6 h后,提取总RNA,通过半定量PCR和实时定量PCR检测单层培养组和共培养组中后交叉韧带成纤维细胞中赖氨酰氧化酶基因表达。 结果与结论:与单层培养组相比,赖氨酰氧化酶、赖氨酰氧化酶样蛋白1、赖氨酰氧化酶样蛋白2、赖氨酰氧化酶样蛋白3和赖氨酰氧化酶样蛋白4的基因表达在共培养的后交叉韧带细胞中都明显升高,分别增加了1.1,1.4,1.1,1.3,1.1倍(P < 0.05)。单层培养组家族成员在单层培养和共培养中表达情况的差异性,说明细胞之间的相互作用会影响后交叉韧带组织的损伤修复,对后交叉韧带损伤修复的机制研究有极其重要的参考价值。  相似文献   
942.
943.
Infants requiring parenteral nutrition (n = 244) were randomized to receive either 1 (group 1, n = 121) or 0.0182 micromol/kg/d (group 2, n = 123) of manganese supplementation. The whole-blood manganese and serum direct bilirubin concentrations of the infants were monitored, as was the development of cholestasis (peak serum direct bilirubin concentration >50 micromol/L). Subgroup analysis was carried out on the data of 78 infants in group 1 and 82 in group 2 who had received manganese supplementation and more than three-quarters of their total daily fluid as parenteral nutrition for >14 d. Of all the infants randomized, the high manganese group (group 1) showed a trend towards developing higher peak whole-blood manganese concentration [group 1 versus group 2: median (interquartile range): 606.0 (421.0; 1005.0) vs 566.0 (336.0: 858.0); p=0.061] and higher peak serum direct bilirubin concentration [37.0 (10.5; 122.5) vs 19.0 (8.0; 112.5); p=0.153], but the differences between the 2 groups did not reach statistical significance. The 2 groups did not differ in terms of the occurrence of cholestasis during parenteral nutrition (63/121 vs 57/123; p=0.444). Subgroup analysis of infants who had received more than three-quarters of their total daily fluid as parenteral nutrition showed, however, that the high manganese group developed significantly higher whole-blood manganese concentration [743.5 (498.0; 1211.0) vs 587.0 (438.0; 982.0); p=0.037] and serum direct bilirubin concentration [84.0 (28.0; 170.0) vs 25.5 (9.0; 117.0): p < 0.001]. Although there was no significant difference in the occurrence of cholestasis (58/78 vs 49/82; p = 0.073), more infants in the high manganese group developed a more severe degree of direct hyperbilirubinaemia, with peak serum direct bilirubin >100 micromol/L (32/78 vs 20/82; p = 0.038). Conclusion: We conclude that the pathogenesis of parenteral nutrition-related cholestasis is probably multifactorial, and that high manganese intake is a significant contributory factor.  相似文献   
944.
Encapsulating peritoneal sclerosis (EPS) is a rare, but sometimes fatal, complication of peritoneal dialysis characterized by diffuse thickening and encapsulation of the bowel and peritoneum. In more advanced cases, the peritoneum will gradually calcify. EPS usually presents as partial small bowel obstruction and diagnosed on imaging studies. We present a case of a 19-year-old female on long-term peritoneal dialysis with EPS and diffuse peritoneal calcifications.  相似文献   
945.
946.

Background

Kidney transplant recipients are at risk for a severe course of COVID-19 with a high mortality rate. A considerable number of patients remains without a satisfactory serological response after the baseline and adjuvant SARS-CoV-2 vaccination schedule.

Methods

In this prospective, randomized study, we evaluated the efficacy and safety of one and two booster doses of mRNA vaccines (either mRNA-1273 or BNT162b2) in 125 COVID-19 naive, adult kidney transplant recipients who showed an insufficient humoral response (SARS-CoV-2 IgG <10 AU/ml) to the previous 2-dose vaccination schedule. The primary outcome was the difference in the rate of a positive antibody response (SARS-CoV-2 IgG ≥10 AU/ml) between one and two booster doses at 1 month after the final booster dose.

Results

A positive humoral response was observed in 36 (62%) patients receiving two booster doses and in 28 (44%) patients receiving one booster dose (odds ratio [OR], 2.10, 95% confidence interval [CI], 1.02–4.34, p = .043). Moreover, median SARS-CoV-2 IgG levels were higher with two booster doses (p = .009). The number of patients with positive virus neutralizing antibody (VNA) levels was numerically higher with two booster doses compared to one booster dose, but without statistical significance (66% vs. 50%, p = .084). There was no significant difference in positive seroconversions rate and antibody levels between mRNA-1273 and BNT162b2.

Conclusion

A higher number of kidney transplant recipients achieved a positive antibody response after two booster doses compared to one booster dose.

  相似文献   
947.
Zellweger Syndrome (ZS) is a rare peroxisomal disorder also referred to as cerebrohepatorenal syndrome. ZS is an autosomal recessive disease often manifesting in the neonatal period with profound dysfunction of the central nervous system, liver and kidneys. Prenatal diagnosis of this syndrome is infrequent with imaging findings on fetal MRI rarely illustrated in the literature. This case highlights the pivotal role fetal MRI can play in identifying subtle features of the disease that are difficult to visualize on prenatal ultrasound. It is important for pediatric radiologists to be familiar with the most common imaging features of ZS on fetal MRI to expedite the diagnosis and help facilitate appropriate prenatal counseling.  相似文献   
948.
Cystic dysplasia of the rete testis is a rare benign abnormality seen in the pediatric population. Diagnosed by scrotal ultrasonography, this lesion is often associated with congenital renal tract anomalies, most commonly ipsilateral renal agenesis or multicystic dysplastic kidney. Treatment traditionally involves orchiectomy or testicular sparing surgery; however, conservative treatment with surveillance has been used as an appropriate alternative. We present the case of a 5-year-old boy with cystic dysplasia of the rete testis with associated unilateral renal agenesis.  相似文献   
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