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The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.  相似文献   
4.
Reactive arthritis (ReA) induced by infection with several gram-negative bacteria is strongly associated with expression of the major histocompatibility complex class I molecule HLA-B27. It is thought that due to the intracellular lifestyle of ReA-inducing bacteria, bacterial fragments can be presented by HLA-B27. Cytotoxic T cells recognizing such bacterial peptides or other induced host peptides could cross-react with self peptides presented in the joints, giving rise to disease. Studies to analyze the B27 peptide repertoire in relation to infection were severely hampered, as complex peptide profiles obtained from separate infected and noninfected cell preparations had to be compared. For this study, we applied a new approach to examine the effect of Salmonella enterica serovar Typhimurium infection on the B27 peptide repertoire presented by the HLA-B*2704 subtype associated with disease. Firstly, we showed that both host cell and S. enterica serovar Typhimurium proteins can be tagged metabolically with stable-isotope-labeled arginine. We then designed experiments so that either the tagged endogenous or tagged bacterial B*2704-presented peptide repertoires from infected cells could be analyzed by mass spectrometry from single peptide preparations that included uninfected controls. Using this new approach, we found no evidence for significant changes in endogenous B*2704 peptide presentation after infection or for any S. enterica serovar Typhimurium-derived B27-bound peptide. In conclusion, the hypothesis that S. enterica serovar Typhimurium induces changes in B27 peptide presentation could not be supported.  相似文献   
5.
The theoretical basis and instrumental requirements of an optical detection technique for monitoring antibody-antigen reactions at a quartz-liquid interface are described. The antibody is covalently immobilized on the optical surface of a planar, fused-quartz waveguide and reacted with antigen solution. A light beam is internally reflected within the waveguide and penetrates into the solution only a fraction of the wavelength of the incident light. This is the evanescent wave which interacts optically with the growing number of antigen-antibody complexes but minimally with the bulk solution. A two-site immunofluorescent assay for human IgG measurement is described using fluorescein as the label. The assay detection limit is approximately 0.8 micrograms/ml and individual fluorescence measurements are completed within 10 min. It is expected that this evanescent wave immunoassay should have wide applicability in both routine and research fields.  相似文献   
6.
Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria.  相似文献   
7.
Use of 24‐hour ambulatory blood pressure monitoring is strongly endorsed by contemporary hypertension guidelines. The objective of this study was to assess patient perceptions of ambulatory blood pressure testing, tolerability, accessibility, and expense. A convenience sample of 50, consenting patients undergoing ambulatory blood pressure monitoring at the University of Alberta Hypertension Clinic in Edmonton, Canada was studied. A 16‐item structured questionnaire was administered in person or electronically. Questions regarding the tolerability of ambulatory monitoring were evaluated using a 5‐point Likert scale and wait times, expenditures, and willingness to pay were evaluated by direct questioning. Mean age was 53.1 ± 15.4 years, 32 (64%) were female, and 23 (46%) were employed. Mean 24‐hour ambulatory BP was 134 ± 12/79 ± 8 mmHg. Ambulatory monitoring caused discomfort in 40 (80%) patients and disturbed sleep in 39 (78%). Forty‐one (82%) patients perceived that the home (vs pharmacy, primary care clinic, and speciality care clinic) would be the easiest venue to access future testing. On average, patients waited 27.3 ± 23.7 days for testing; they felt that a wait time of 21.3 ± 12.3 days was appropriate. Mean time taken off work was 8.6 ± 10.8 hours. Twelve (24%) patients indicated that they would be willing to pay out‐of‐pocket to undergo testing sooner, at a mean expenditure of $120 ± 69. Nineteen (62%) patients were willing to buy a monitor and felt that a mean purchase cost of $125 ± 89 was appropriate. These findings extend current knowledge of patient perceptions of ambulatory monitoring and may help to refine and optimize future delivery of this essential test.  相似文献   
8.

Background

Traditional periodontal open flap debridement (OFD) results in reduced pocket depth (PD), clinical attachment loss (CAL), gingival recession (GR) and postoperative pain and discomfort. The quest to overcome these shortcomings has led to research into Er,Cr:YSGG laser assisted pocket therapy (ELAPT). This study was designed to compare the clinical outcomes of ELAPT versus OFD.

Methods

Fifteen patients with a PD of ≥5 mm and ≤8 mm at two sites were selected. Test sites (Group 1) were treated by ELAPT and the control (Group 2) by OFD. Clinical parameters were recorded at baseline, 3 and 6 months and included Plaque Index (PI), Gingival Index (GI), modified Sulcular Bleeding Index (mSBI), PD, CAL and GR.

Results

Both treatments produced a reduction in PI, GI, mSBI and PD, an increase in GR, and a gain in CAL at 3 and 6 months. The mean gain of CAL in Group 1 at 3 and 6 months (1.60 ± 0.78 and 1.80 ± 0.63) was similar (p > 0.05) to the value of Group 2 (1.93 ± 0.88 and 2.00 ± 0.54). GR increased significantly (p < 0.05) only in Group 2 at 3 and 6 months (1.80 ± 0.56 and 1.87 ± 0.64) compared to Group 1 (0.50 ± 0.68 and 0.60 ± 0.74).

Conclusions

ELAPT compared with OFD results in similar CAL gains with less GR and significant reductions in PD, GI and mSBI, and may be considered as an alternative to surgical therapy.  相似文献   
9.

INTRODUCTION

Surgical stress in the presence of fasting worsens the catabolic state, causes insulin resistance and may delay recovery. Carbohydrate rich drinks given preoperatively may ameliorate these deleterious effects. A systematic review was undertaken to analyse the effect of preoperative carbohydrate loading on insulin resistance, gastric emptying, gastric acidity, patient wellbeing, immunity and nutrition following surgery.

METHODS

All studies identified through PubMed until September 2011 were included. References were cross-checked to ensure capture of cited pertinent articles.

RESULTS

Overall, 17 randomised controlled trials with a total of 1,445 patients who met the inclusion criteria were identified. Preoperative carbohydrate drinks significantly improved insulin resistance and indices of patient comfort following surgery, especially hunger, thirst, malaise, anxiety and nausea. No definite conclusions could be made regarding preservation of muscle mass. Following ingestion of carbohydrate drinks, no adverse events such as apparent or proven aspiration during or after surgery were reported.

CONCLUSIONS

Administration of oral carbohydrate drinks before surgery is probably safe and may have a positive influence on a wide range of perioperative markers of clinical outcome. Further studies are required to determine its cost effectiveness.  相似文献   
10.
目的探讨蜂胶对糖尿病伤口愈合的作用及其机制。方法采用荧光电泳法,检测不同葡萄糖浓度(5、25mmol/L)和不同蜂胶浓度(10、50、100、200μg/ml)处理的体外培养的人成纤维细胞及单核巨噬细胞系的基质金属蛋白酶MMP-9蛋白的表达。结果高浓度葡萄糖(25mmol/L)状态下,MMP-9表达增加,但与低浓度(5mmol/L)比较,差异无统计学意义。蜂胶可显著降低MMP-9的表达,并呈剂量依赖性(P〈.05)。结论高糖能增加单核巨噬细胞系及成纤维细胞MMP-9的表达,可能会影响糖尿病患者伤口的愈合。蜂胶可抑制这些细胞MMP-9的表达,有益于细胞基质的积聚,从而有益于糖尿病患者伤口的愈合。  相似文献   
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