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991.
992.
C. Whitham D. D Mellor S. Goodwin M. Reid S. L. Atkin 《Journal of human nutrition and dietetics》2014,27(4):384-390
993.
目的探讨出生体重大于2000g的新生儿眼底疾病的发生情况及开展早产儿视网膜病筛查的必要性。方法用双目间接眼底镜和(或)RetCamⅢ对2012年出生的636例新生儿进行眼底筛查,按胎龄分为两组(胎龄≥37周组和胎龄〈37周组),分析比较各种眼底疾病的发生及救治情况。结果总患病概率为12.89%。其中最常见的眼底病变为视网膜出血(占8.65%)、早产儿视网膜病(占2.20%)和玻璃体混浊(占0.94%)。结论这类新生儿最常见眼底疾病为视网膜出血,顺产新生儿发生率高于剖宫产新生儿。积极地开展眼底筛查,进行随访很有必要。 相似文献
994.
目的:观察LED白光治疗低出生体重儿病理性黄疸的临床治疗效果。方法53例低体重新生儿病理性黄疸患儿随机分2组:治疗组28例予LED白光治疗,对照组25例给予普通蓝光治疗,对两组疗效及副作用进行对比分析。结果胆红素下降值,黄疸消退速度,治疗组均优于对照组(P<0.05),不良反应发生率治疗组低于对照组(P<0.05)。结论LED白光治疗低体重新生儿病理性黄疸安全、有效,能减少不良反应的发生率,缩短治疗时间。 相似文献
995.
以新冬18号为材料,利用双管分根管栽法,模拟田间试验研究了拔节期后不同滴灌次数W1(6次)、W2(7次)、W3(9次)、W4(11次)(每次内、外管分别滴30 mm)对0~100 cm土层含水量,0~100 cm土层初、次生根干重和长度、根系活性分布及产量的影响。结果表明,随滴灌次数及总滴灌量的增加,0~40 cm土层的含水量增加,并延缓该土层的初生根干重和根长的衰减、促进次生根干重和根长增长,增加孕穗期至花后20 d初、次生根干重密度、根长密度及根系活性,而对40~100 cm土层根系的生长影响较小。小麦产量和水分利用效率均以W4最高,分别为25.5 g·管-1和1.36 kg·m-3
。当滴灌量少、湿润土层浅时,小麦深层初、次生根生长易受严重抑制,且根系分布浅,初生根提前衰老,导致千粒重降低而减产。 相似文献
996.
《Pathology, research and practice》2020,216(8):153021
Acute allograft rejection is the most common complication in organ transplantation leading to organ loss. Treg cells play an important role in preventing acute rejection, but they are unstable and easily lose function. Poly(ADP-ribose) polymerase 1(PARP-1) is involved in the differentiation stabilization of Treg cells, it has been suggested that PARP-1 inhibition could prevent acute rejection and prolong allograft survival. This study investigated AG14361 effects on acute allograft rejection. We used a fully MHC-mismatched murine heart transplantation model to compare the effect of PARP-1 inhibitor-AG14361 on alloimmunity to the control. Mice treated with PARP-1 inhibitors showed a longer median survival time of allografts (MS14 compared with the control group, MST was 8 days, and AG14361 was 6 days, P = 0.019). The combination of sirolimus and AG14361 significantly delayed allograft MST (AG14361 + sirolimus for 30 days, sirolimus for 16 days, P = 0.002). AG14361 markedly augmented the number of the CD25+FoxP3+ Treg cells in the graft and periphery. In addition, it could enhance the suppressive function of Treg cells by upregulating the level of CTLA-4, PD-1 and ICOS. In vivo, the Treg/Th17 ratio increased significantly in the AG14351 group compared to the control. In the combination with sirolimus treatment, AG14361 promoted the long-term allograft survival. Our results highlight novel effects of a PARP-1 inhibitor. PARP-1 inhibitor AG14361 may be a promising agent to attenuate acute allograft rejection as it can maintain the number and function of Treg cells in allografts. 相似文献
997.
《Human immunology》2020,81(7):337-341
Short-term allograft survival has improved among solid organ transplant (SOT) patients. An increasing number of SOT patients are prepared for re-transplantation because of chronic allograft failure. Lack of HLA typing or incomplete HLA typing of previous donors complicates pretransplant risk assessment, as repeated HLA mismatches may be missed. In addition, a complete HLA type of the donor is essential in the diagnosis of antibody-mediated rejection. We aimed to determine donor HLA types from allograft biopsies from kidney, heart and liver grafts.Graft biopsies were obtained from 13 kidney, heart and liver transplanted patients. HLA typing was performed using q-PCR. Alleles of both donor and recipient origin were detected, and donor HLA type was concluded by deducting known HLA types of the recipient. For all 13 patients, we were able to determine mismatched donor HLA alleles from graft material. These results are promising, because they enable better individualized risk assessment. 相似文献
998.
Kai Wang Yulong Jin Boping Liu Rui Zhang He Ren Ning Zhao Xuelian He 《Macromolecular chemistry and physics.》2020,221(7)
Polyethylene (PE) with bimodal molecular weight distribution (MWD) has drawn attention from both academia and industry. Bimodal PE combines great processability with outstanding mechanical properties. The single‐reactor technology process through a dual site catalyst system is an optimal strategy considering the economic effect and the manufacturing technique. To satisfy the demand of the dual site catalyst system for producing bimodal PE, novel SiO2‐supported chromium oxide/chromocene dual site catalysts for ethylene polymerization are successfully synthesized and systematically investigated. The novel catalysts are prepared by using the residual hydroxyl groups on the surface of SiO2‐supported chromium oxide (CrOx) Phillips catalyst to introduce chromocene. It is found that the novel dual site catalysts combine the advantages of chromocene catalyst (S‐9 catalyst) and Phillips CrOx/SiO2 catalyst. The activities of the dual site catalysts are doubled at least compared to the S‐9 catalyst due to the high activity of the CrOx active center. The products of the dual site catalysts show significantly high molecular weight (MW) with bimodal MWD through ultrahigh molecular weight polyethylene/high‐density polyethylene in reactor alloys. The dual site catalysts show great hydrogen response according to the hydrogen experiment results, which lead to the easy control of MW. 相似文献
999.
1000.
Michael D. Hughson Wendy E. Hoy John F. Bertram 《Anatomical record (Hoboken, N.J. : 2007)》2020,303(10):2526-2536
Two major studies of structural changes associated with aging in human kidneys are reviewed and new information presented. The studies are the Monash University stereologically analyzed series of 319 autopsy kidneys from the United States in which 44% were white and the Mayo Clinic CT angiogram/biopsy analysis of 1,388 US kidney donors in which 97% were white. Hypertension rates in the Monash series were 48% and included moderate and severe hypertension. In the Mayo Clinic study, 12% had mild hypertension. The studies showed no relationship between glomerular number and hypertension except for a weak relationship with older white women in the Monash series. An inverse relationship was present between glomerular number and glomerular volume, a reciprocity that tended to enhance glomerular mass and by inference filtration capacity with lower nephron numbers. This relationship seemed to be present whether low nephron numbers were intrinsic or acquired. In the Mayo Clinic studies, pretransplant iothalamate clearances demonstrated that single nephron (SN) glomerular filtration rates (GFR) were similar throughout the range of glomerular number in subjects younger than 70 years, but that increased SNGFR correlated with nephron hypertrophy and increased nephrosclerosis particularly at 70 years of age and over. Hypertension at least through middle age cannot be related to a deficiency of glomeruli, but glomeruli are lost with later aging in association with adaptive nephron hypertrophy that can maintain GFR near normal. These studies help define an age-related nephropathy that overlaps with hypertension as a potential cause of end-stage renal disease when glomerulosclerosis is advanced. 相似文献