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91.
The Hu and Islet-1 proteins are early markers of neuronal differentiation in the avian embryo. We here examine which of these markers is expressed first in avian dorsal root ganglia (DRG). Recently we showed that neural tube and DRG cells express Islet-1 after leaving the cell cycle, while sympathetic ganglion cells express Islet-1 while still dividing. Others have shown that Hu is found in cells that take up BrDU in the DRG, suggesting that it is expressed even earlier in the differentiation process than Islet-1. In this study we double-label sections for Hu and Islet-1 at several stages of embryonic development, using a simple antigen retrieval method in paraffin sections. At early stages many more cells are Islet-1(+) than Hu(+). In addition, although many cells express both markers, some Islet-1(+)/Hu(-) cells are observed but the converse is never found. At later stages, almost all DRG neurons express both markers, although a few Islet-1(+)/Hu(-) cells are still observed. Staining for Hu and Islet-1 at a later stage than previously reported shows that neither marker is expressed in DRG satellite cells. Our results suggest that Islet-1 is a useful marker for DRG neurons at earliest embryonic stages, and is likely to be expressed in DRG neurons before the Hu antigen. 相似文献
92.
目的
探讨先天性心脏病(CHD)患儿肺动脉高压(PH)形成的影响因素.方法
研究对象均为2003-06-2005-02于北京大学深圳医院收集病例,以健康者30名为对照组(A组),以肺动脉压正常和并发PH的左向右分流的CHD患儿各30例为观察组(B组、C组).以高效液相色谱法、硝酸还原法及放射免疫法测定其血清精氨酸(L-Arg)、一氧化氮(NO)、血浆内皮素(ET-1)的浓度.结果
血清L-Arg浓度对照组(A组)为(72.00±18.01)nmol/mL,肺动脉压正常的患儿(B组)为(30.74±8.97)nmol/mL,伴PH的患儿(C组)为(23.51±12.37)nmol/mL.血清NO浓度A组为(76.10±17.10)nmol/mL,B组(90.55±26.57)nmol/mL,C组(60.05±17.60)nmol/mL.血浆ET-1浓度A组(50.82±7.58)pg/mL,B组(64.90±16.28)pg/mL,C组(69.64±10.66)pg/mL.结论
血清NO浓度和血浆ET-1浓度及其之间的平衡关系共同影响PH的形成及其程度.血浆ET-1浓度的升高是肺动脉压升高的直接因素,血清NO浓度的降低是间接因素,而血清NO浓度降低是由血清L-Arg浓度的降低引起. 相似文献
93.
目的探讨血液透析(HD)及血液透析滤过(HDF)治疗急性肾衰竭患儿前后血清陉微球蛋白(β2-MG)及下降率的影响。方法对各种原因导致的急性肾衰竭需行血液净化治疗38例患儿随机分成2组。HD组20例,HDF组18例。透析前后分别测血清β2-MG水平。结果HDF与HD前后血清陉.MG变化经统计学处理。HDF组治疗前后血清β2-MG水平差异有显著性意SL(P〈0.01);HD组治疗前后血清β2-MG水平差异无显著性意义(P〉0.05);HDF和HD组治疗后比较血清β2-MG水平差异、下降率差异均有显著性意义(P均〈0.01)。结论HDF清除血β2-MG明显优于HD。 相似文献
94.
目的分析小儿脱髓鞘疾病的临床特点,以提高对该疾病的诊断与治疗。方法对51例小儿脱髓鞘疾病的发病年龄、前驱症状、临床表现及辅助检查特点等进行回顾性分析。结果51例脱髓鞘疾病患儿中学龄期38例,有前驱感染史32例,疫苗接种史3例,大多以急性起病。周围神经脱髓鞘疾病32例以双下肢或四肢瘫痪为首发;中枢神经脱髓鞘疾病以视力障碍、肢体无力、发热、抽搐、头痛等为首发。周围神经脱髓鞘疾病患儿中15例行肌电图检查,均显示为神经源性改变;18例中枢神经脱髓鞘疾病患儿中17例行CT或MRI,均发现异常信号。结论小儿脱髓鞘疾病的临床表现复杂多变,通过病史及辅助检查,进行综合分析,不难得出诊断,预后良好。 相似文献
95.
96.
双黄连与其它常用药物在输液中的配伍观察 总被引:1,自引:0,他引:1
本文详细列举了双黄连与常用药物在输液中的配伍观察,为临床合理用药提供参考。 相似文献
97.
OBJECTIVE To study the inhibition of adhesion and invasion of SGC7901cells into the ECM by integrinβ1 antisense oligodeoxynucleotide asODN.METHODS asODN and control ODN were transfected into SGC7901 cells using liposomes as vectors. The distribution of the ODN was followed by immunochemistry and changes in the expression of integrinβ1 mRNA and protein were determined by RT-PCR and FCM, respectively. The adhesion and invasion into the ECM were measured by the MTT and Boyden chamber methods, respectively.RESULTS Integrinβ1 asODN which was transfected into SGC7901 cells distributed evenly in the cytoplasm and nucleus. PCR and FCM revealed a weakened band at 489bp and a left-shift curve, respectively. Adhesion and invasion assays showed decreased activity with an inhibition rate of 54% and 76%. The extent of decrease induced by integrinβ1 asODN was larger than that caused by random control ODN (P<0.001).CONCLUSION Transfection of integrinβ1 asODN into SGC7901 cells induced a decrease in the expression of integrinβ1 mRNA and protein,resulting in a decrease in adhesion and invasion into the ECM, with a greater effect than random control ODN. 相似文献
98.
Su-rong YANG Li WEN Ying-qing LU Qin-yan GONG Rong YU Ming-hui YAODepartment of Pharmacology Shanghai Medical College Fudan University Shanghai China 《Acta pharmacologica Sinica》2004,(1)
AIM: To observe the effects of three cytokines on the apoptosis of Tf-1 cells induced by y irradiation and investigate the relationship between apoptosis and caspase-3 activity. METHODS: Different cytokines GM-CSF, IL-3 and GM-CS/IL-3 fusion protein were added into the irradiated Tf-1 cells. MTT assay, morphology, flow cytometry, and DNA fragmentation assay were used to observe the effects of cytokines on apoptosis. The caspase-3 activity was determined with a fluorocytometer. RESULTS: Irradiated Tf-1 cells showed typical morphological characteristic of apoptosis demonstrated by transmission electron microscopy and were accumulated in G0/G1 phase. In the groups treated with growth factors after irradiation, three cytokines significantly increased the viability rate, distinctly decreased the apoptosis rate and the proportion of DNA fragmentation. When Tf-1 cells were irradiated by y 相似文献
99.
ObjectiveTo analyze the use of packed red blood cells (PRBCs) for patients with pelvic fracture and evaluate factors associated with PRBC transfusion for patients with pelvic fracture.MethodsThis retrospective cohort study collected 551 patients with pelvic fractures from six hospitals between September 1, 2012, and June 31, 2019. The age span of patients varied from 10 to 95 years old, and they were classified into two groups based on high‐energy pelvic fractures (HE‐PFs) or low‐energy pelvic fractures (LE‐PFs). The study''s outcome was the use of PRBCs, fresh frozen plasma (FFP), and albumin. Demographic data, characteristics, laboratory tests, clinical treatment details, and clinical outcomes were compared between the two groups. Factors that were statistically associated with perioperative PRBCs in univariate analyses were included to conduct an optimal scale regression to determine the independent factors for perioperative PRBCs.ResultsA total of 551 patients were screened from six hospitals, and after inclusion and exclusion, 319 were finally included and finished the follow‐up from admission to discharge, while four patients died during hospitalization. Three hundred and nineteen patients were classified into two groups by their injury mechanisms. A total of 230/319 (72.1%) patients were classified into the HE‐PF group, and 89/319 (27.8%) patients were classified into the LE‐PF group. Patients in the HE‐PF group were transfused with 4.5 (3–8) units of PRBCs, 300 (0–600) ml of FFP, and 0 (0–30) g of albumin, while patients in the LE‐PF group were transfused with 3.5 (2–4.5) units of PRBCs, 0 (0–295) ml of FFP, and 0 (0–0) g of albumin (all P < 0.001). There were higher proportions of male patients and patients under 65 in the HE‐PF group (all P < 0.001). HE‐PF group patients were more severely injured and likely to take external fixation. The optimal scale regression revealed four significant factors associated with perioperative transfused PRBCs, which were patients on admission with hemorrhagic shock (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.148, P = 0.039), and methods of pelvic fixation (importance = 0.008, P = 0.026), ranked by the importance.ConclusionPatients with HE‐PFs had increased transfusions of PRBCs, FFP, and albumin, and hemorrhagic shock on admission, Tile classification, Hb levels, and stabilization methods were found to be associated with perioperative PRBCs. 相似文献
100.
Jiajia Chen Chunshuai Wu Hongxiang Hong Xiangyu Wang Jinlong Zhang Pengfei Xue Jiawei Jiang Dan Wang Zhiming Cui 《Orthopaedic Surgery》2022,14(8):1630
ObjectiveTo translate the original English version of the Spinal Instability Neoplastic Score (SINS) into simplified Chinese, adapt it cross‐culturally, validate its psychometric properties in measuring spinal instability in patients with metastatic spinal tumors in the Chinese mainland, examine the reliability and validity to demonstrate its accuracy and applicability in clinical practice.MethodsPatients diagnosed with metastatic spinal disease between January 2016 and January 2020 were recruited. The number of participants was advised to be at least 50 for appropriate analysis of reliability, construct validity, as well as ceiling or floor effects, and recruitment of 100 patients was advised for internal consistency analysis. The study was conducted in two phases: first, the SINS was translated into simplified Chinese; second, the factor structure, internal consistency, test–retest reliability, validity, and floor and ceiling effects of the SC‐SINS were assessed. The internationally recognized cross‐cultural adaptation guidelines were followed. Internal consistency was evaluated with Cronbach''s alpha. Test–retest reliability was examined among the patients with a 4‐week interval. The validity of the Chinese version of SINS (SC‐SINS) was assessed by examining its relationship with Kostuik classification. Principal component analysis was conducted to confirm the factor structure of each subscale.ResultsA total of 160 participants (88 males and 72 females) were enrolled. No major difficulties occurred in the forward and backward translations of SINS. The internal consistency of SC‐SINS was excellent (Cronbach''s α =0.857, ranging from 0.68 to 0.85). Test–retest reliability was also excellent with a value of 0.89, ranging from 0.86 to 0.95. Validity analyses indicated that the SC‐SINS was positively and significantly correlated with Kostuik classification. The correlation between “Posterolateral Involvement of Spinal Elements” and “1‐2 Partial Damage” was the highest with a correlation value of 0.792. The correlation between “Pain” and “1–2 Partial Damage” was the lowest with a value of 0.341. All items showed principal component coefficients greater than 0.4. The values of Factor 1 ranged from 0.523 to 0.681; Factor 2 ranged from 0.591 to 0.731; Factor 3 ranged from 0.613 to 0.754; Factor 4 ranged from 0.461 to 0.711; Factor 5 ranged from 0.513 to 0.701; and Factor 6 ranged from 0.501 to 0.668. In addition, neither floor nor ceiling effects were seen in the SC‐SINS.ConclusionThe SC‐SINS demonstrated high internal consistency and test–retest reliability, which has been proven valid and reliable to measure spinal stability in patients from the Chinese mainland with metastatic spinal tumor. 相似文献