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21.
The neonatal brain is vulnerable to oxidative stress, and the pentose phosphate pathway (PPP) may be of particular importance to limit the injury. Furthermore, in the neonatal brain, neurons depend on de novo synthesis of neurotransmitters via pyruvate carboxylase (PC) in astrocytes to increase neurotransmitter pools. In the adult brain, PPP activity increases in response to various injuries while pyruvate carboxylation is reduced after ischemia. However, little is known about the response of these pathways after neonatal hypoxia-ischemia (HI). To this end, 7-day-old rats were subjected to unilateral carotid artery ligation followed by hypoxia. Animals were injected with [1,2-13C]glucose during the recovery phase and extracts of cerebral hemispheres ipsi- and contralateral to the operation were analyzed using 1H- and 13C-NMR (nuclear magnetic resonance) spectroscopy and high-performance liquid chromatography (HPLC). After HI, glucose levels were increased and there was evidence of mitochondrial hypometabolism in both hemispheres. Moreover, metabolism via PPP was reduced bilaterally. Ipsilateral glucose metabolism via PC was reduced, but PC activity was relatively preserved compared with glucose metabolism via pyruvate dehydrogenase. The observed reduction in PPP activity after HI may contribute to the increased susceptibility of the neonatal brain to oxidative stress.  相似文献   
22.
Circulating inhibitors against von Willebrand factor (vWF) that show the properties of heterologous IgG antibodies have been described in a few patients with severe von Willebrand disease (vWD). The present study provides further characterization of inhibitors from two patients with severe vWD. Inhibitors in both, like polyclonal rabbit antibody, detected all sizes of multimers and the complex structure of each multimer from platelets and plasma of normal individuals as well as from plasma of patients with IIA, IIB, and IIC vWD. Both inhibitors and the rabbit antibody reacted mainly with the intact 225-Kd vWF subunit and the 189-H and 140-Kd fragments in contrast to monoclonal antibodies specific for vWF fragments that detected a higher relative proportion of 176-Kd fragment. Furthermore, all these antibodies recognized fragment III, although one inhibitor and rabbit polyclonal antibody reacted poorly and the other inhibitor did not react at all with reduced fragment II of vWF digested with Staphylococcus aureus V-8 protease. These data suggest that although human inhibitors from severe vWD patients may behave, to some extent, as polyclonal heterologous antibodies against native vWF, the former show striking differences in their target specificity as well as a much broader specificity than that described for human factor VIII inhibitors.  相似文献   
23.
Passive intestinal permeability in 33 newborn babies was studied using feeds containing lactulose and mannitol. Each marker is thought to pass across the gut wall by a different route; lactulose by a paracellular and mannitol by a transcellular pathway. Neither is metabolised and both are wholly and solely excreted by the kidney; urinary recovery is a measure of the intestinal uptake. Babies born before 34 weeks' gestation exhibited a higher intestinal permeability to lactulose than more mature babies, and all preterm babies showed an appreciable decline in lactulose absorption during the first week of oral feeds. Babies of 34 to 37 weeks' gestation achieved a 'mature' intestinal permeability to lactulose within four days of starting oral feeds. These findings may reflect the immaturity of the gut of the preterm baby rather than a process essential to adaptation to enteral nutrition.  相似文献   
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25.
The prevalence of dyslipidaemia in children with insulin dependent diabetes mellitus (IDDM) and its relation to glycaemic control was studied in a group of 51 diabetic children and a control population of 132 schoolchildren. The prevalence of dyslipidaemia in the fasting state was increased in the diabetic group (39%) compared with control subjects (17%). Serum cholesterol concentration alone was raised in 25% of diabetic subjects while serum cholesterol and triglycerides were raised in 14%, compared with 16% and 0.7% respectively in control subjects. Serum total cholesterol (5.1 v 4.5 mmol/l), low density lipoprotein cholesterol (3.2 v 2.6 mmol/l), non-esterified fatty acids (0.91 v 0.50 mmol/l), and triglycerides (0.94 v 0.76 mmol/l) were higher in diabetic children. Serum total cholesterol, triglycerides, and apolipoprotein (apo)B concentrations increased with worsening control, while serum high density lipoprotein cholesterol and apoA-I concentrations were unaltered. There were also positive correlations between glycated haemoglobin and total cholesterol, triglycerides, and apoB in diabetic children. Thus, abnormalities in circulating lipids are common in young subjects with IDDM but largely disappear if blood glucose concentrations are reasonably controlled.  相似文献   
26.
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option of surgery. Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml. Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed. Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106). Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2). Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative lymph node frozen section.  相似文献   
27.
Somatostatinomas are rare neuroendocrine tumors; they are essentially located in the pancreas and in the duodenum. The association with a neurofibromatosis type I is especially observed when the tumor is located in the ampulla of Vater. These tumors are not associated with a "somatostatin syndrome", but often present with gastrointestinal bleeding, abdominal pain and obstructive jaundice. The diagnosis is confirmed by immunohistochemical studies. The aim of this study is to report 2 cases of metastazing duodenal periampullary somatostatinomas associated with von Recklinghausen's disease and to discuss the prognosis of these tumors. Future genetic research are necessary as point out the familial feature of this association in one of our cases.  相似文献   
28.
高效液相色谱法测定寒痹停片中士的宁含量   总被引:6,自引:0,他引:6  
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。  相似文献   
29.
A third case of chondrodysplasia punctata after exposure to warfarin alone in early pregnancy is described. The clinical course of the child during the first 18 months is outlined. The use of warfarin in early pregnancy must be avoided because of its established teratogenic effects in causing this syndrome, in addition to an overall increase in perinatal mortality.  相似文献   
30.
Introduction and ObjectivesThe emergence of SARS-CoV-2, which causes the coronavirus disease (COVID-19) has caused a great impact on healthcare systems worldwide, including hepatitis B and C viruses screening and elimination programs. The high number of COVID-19 hospitalizations represent a great opportunity to screen patients for hepatitis B virus (HBV) and hepatitis C virus (HCV), which was the aim of this study.Material and MethodsCross-sectional, retrospective study performed between April 2020 and 20201 at a referral center in Mexico dedicated to the care of adults with severe/critical COVID-19. We retrieved clinical, demographic, and laboratory results from each patient´s medical records, including antibodies against HCV (anti-HCV), HBV surface antigen (HBsAg), antibodies against the HBV core antigen (anti-HBcAg), and antibodies against HBsAg (anti-HBsAg).ResultsOut of 3620 patients that were admitted to the hospital, 24 (0.66%), 4 (0.11%), and 72 (1.99%) tested positive for anti-HCV, HBsAg, and anti-HBcAg, respectively. Of all seronegative patients, 954 (27%) had undetectable anti-HBsAg and 401 (12%) had anti-HBsAg at protective levels. Blood transfusion was the most relevant risk factor. Only 9.7% of the anti-HBc positive, 25% of the HBsAg positive, and 52% of the anti-HCV positive were aware of their serological status.ConclusionsIn this study we found a prevalence of anti-HCV of 0.66%, HBsAg in 0.11%, and isolated anti-HBcAg in 1.99%. We also found that HBV vaccination coverage has been suboptimal and needs to be reinforced. This study gave us a trustworthy insight of the actual seroprevalence in Mexico, which can help provide feedback to the Hepatitis National Elimination Plan.  相似文献   
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