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31.
32.
Infants with significant congenital heart disease (CHD) typically require transport from their birth centre to a regional paediatric cardiac centre. Antenatal diagnosis of CHD allows early pre-emptive stabilisation, and is associated with improved early clinical status. However, the effect of antenatal diagnosis on the transport characteristics of infants with CHD has not been previously investigated. The aim of this study was to compare the transport characteristics of infants with antenatal and postnatal diagnosis of CHD. This study is a retrospective cohort study of all infants of ≤10 days and ≥34 weeks of gestation with CHD admitted to the Royal Children's Hospital, Melbourne (RCH) over 5 years. Demographic, diagnosis, and transport data were recorded. Cases of complex CHD were included in this study. Of 320 infants with complex CHD, 198 (62 %) had antenatal diagnosis (ANdx) and 122 (38 %) had postnatal diagnosis (PNdx). There was no significant difference in sex, birth weight, or gestation between ANdx and PNdx groups. Average age of referral was 15 vs. 53.4 h in ANdx vs. PNdx groups. Aggregate transfer distance in the ANdx group was 2216 km and in the PNdx group was 10,274 km (P?<?0.0001). Of the infants, 39 % in the PNdx group required highest-acuity “time critical” transports compared to 6 % of ANdx infants (P?=?0.0001). Conversely, only 11 % of the infants in the PNdx group had lowest acuity “non-urgent” transfers, compared to 24 % of ANdx infants (P?=?0.003). PNdx was associated with significantly higher rates of invasive ventilation (36 vs 20 %; P?=?0.01) and higher rates of inotrope use (19 vs. 9 %; P?=?0.007) during transport. Conclusions: Improved antenatal detection would allow for safer, less resource intense transfers of infants with CHD.  相似文献   
33.

Objectives

This present study was designed to investigate the effects of Angiotensin II on mitochondrial functions, ROS generation and c-jun N-terminal kinases (JNK) signalling pathway-mediated cell apoptosis in mouse calvaria osteoblasts.

Methods

Calvaria osteoblast were isolated and cultured. The cells were separated into two groups—control and treated groups—where the latter was stimulated with angiotensin II (Ang II). Mitochondrial reactive oxygen species (ROS) and superoxide production were measured. Intracellular ATP levels were also detected. The cell proliferation rate was determined for the two groups. Protein production such as Anti-Bax, Bcl-2, COX IV and activation of c-jun N-terminal kinases signal (JNK) pathway was measured by enzyme-linked immunosorbent assay (ELISA) methods and Western blotting in this study.

Results

Ang II treated cells showed significantly higher levels of superoxide production compared to the control group (p < 0.05). Conversely, Ang II induced inhibitory effects on mitochondrial respiratory enzyme complexes, cause membrane potential dissipation, ATP loss and promote ROS generation, cell apoptosis in cultured osteoblasts. In addition, JNK phosphorylations were involved in activating the mitochondria-dependent apoptotic pathway following Ang II stimulation, as pre-treatment of JNK-specific inhibitor SP600125 could rescue osteoblast cells from apoptosis by enhancing the anti-apoptotic protein Bcl-2 expressions, suppressing the translocation of Bax from cytosol into mitochondria, blocking cytochrome C release and caspase-3 activation.

Conclusions

Ang II stimulates osteoblast apoptosis via suppression of the mitochondrial respiratory enzymes, membrane potential and cellular ATP productions. Clinical application with Ang II-stimulated osteoblast could be used for modelling or bone resorption in the oral region.  相似文献   
34.
Bath-related headache   总被引:2,自引:0,他引:2  
Bath-related headache (BRH) is a rare primary headache syndrome. We present our experience over seven years and review all reported cases of BRH. Thirteen patients, including six from our group, are described. BRH occurred exclusively in middle-aged or elderly Oriental women (mean age 51 years, range 32-67. Hong Kong 6 cases, Taiwan 4 cases, Japan 3 cases). The typical presentation was a uniphasic cluster of severe headache recurrently triggered by bathing or other activities involving contact with water. Each attack lasted 30 min to 30 h. Onset was hyperacute, consistent with that of thunderclap headache. Reversible multisegmental cerebral vasoconstriction was found in two patients. No underlying secondary causes were identified. Response to acute treatment was generally unsatisfactory, but headache could be prevented by avoiding the specific trigger(s). BRH runs a self-limiting course; all patients remitted within three months after onset. Nimodipine may shorten the duration of illness.  相似文献   
35.
One hundred and sixty-nine blood and cerebrospinal fluid isolates of Haemophilus influenzae, collected in the Province of Ontario from children and adults from 1976 to 1983, were tested for susceptibility to six conventional and eight newer antibacterial drugs. Most active were ceftriaxone, ceftizoxime and cefotaxime (MIC90 less than or equal to 0.02 mg/l); latamoxef (moxalactam), acrosoxacin and ceftazidime were close behind with MIC90s in the 0.05-0.09 mg/l range. Twenty-five strains (14.8%) were beta-lactamase-producing and thus resistant to ampicillin. There were no chloramphenicol-resistant strains. The isolates showed intermediate but still clinically useful susceptibility to trimethoprim, rifampicin, cefuroxime, piperacillin and chloramphenicol and were least susceptible to gentamicin and sulphamethoxazole.  相似文献   
36.
OBJECTIVES: Prevalence of single quinolone-resistance determining region (QRDR) mutations in Streptococcus pneumoniae was studied from nine institutions over 5 years to track the incidence of single QRDR mutations. METHODS: All 1106 levofloxacin-susceptible pneumococci (MICs < or = 2.0 mg/L) identified from 1112 total isolates (99.5% susceptibility) in TRUST 3 (1999), TRUST 5 (2001) and TRUST 7 (2003) surveillance studies from the same nine hospitals in nine states were screened for QRDR mutations. Using pyrosequencing, the strains were screened for mutations corresponding to hot spots Asp-78, Ser-79 and Asp-83 in ParC; Asp-80, Ser-81 and Glu-85 in GyrA; Asp-435 in ParE and Asp-435 in GyrB. DNA sequencing of QRDRs was performed to confirm mutations. RESULTS: No QRDR mutations were found in any of the isolates with levofloxacin MICs < or = 0.5 mg/L and no gyrA or gyrB QRDR mutations were found in any of the screened isolates (MICs < or = 2 mg/L). Four single-step QRDR mutants with the following amino acid substitutions were found: ParE Asp-435 to Asn (isolated in 1999 in Colorado); ParC Asp-83 to Asn (isolated in 2001 in Kentucky); ParC Ser-79 to Phe (isolated in 2003 in Indiana) and ParC Ser-79 to Tyr (isolated in 2003 in California). These non-clonal strains had levofloxacin MICs of 1 mg/L and were non-susceptible to ciprofloxacin (MIC 2-4 mg/L). CONCLUSIONS: Overall prevalence of single QRDR mutations in levofloxacin-susceptible S. pneumoniae with MICs of < or = 2 mg/L was 0.4% (4/1106) and has remained <1% within nine institutions over 5 years (1999-2003).  相似文献   
37.
OBJECTIVE: To investigate the effect of material stiffness of flat and custom-molded insoles on plantar pressures and stress distribution in the bony and ligamentous structures during balanced standing. DESIGN: A 3-dimensional (3-D) finite element model of the human ankle-foot complex and a custom-molded insole were developed from 3-D reconstruction of magnetic resonance images and surface digitization. The distal tibia and fibula, together with 26 foot bones and 72 major ligaments and the plantar fascia, were embedded in a volume of soft tissues. SETTING: Computational laboratory in a rehabilitation engineering center. PARTICIPANT: A healthy man in his mid twenties (weight, 70 kg). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Foot-support interfacial pressure, von Mises stress in bony structures, and strain of the plantar fascia were predicted using the finite element model. RESULTS: A custom-molded, soft (Young modulus, E=0.3 MPa) insole reduced the peak plantar pressure by 40.7% and 31.6% at the metatarsal and heel region, respectively, compared with those under a flat, rigid (E=1000 MPa) insole. Meanwhile, a 59.7% increase in the contact area of the plantar foot was predicted with a corresponding peak plantar pressure increase of 22.2% in the midfoot. CONCLUSIONS: The finite element analysis implies that the custom-molded shape is more important in reducing peak plantar pressure than the stiffness of the insole material.  相似文献   
38.
To study apolipoprotein A-II, a simple, precise, and accurate immunodiffusion assay was developed and applied in a population sample of industrial employees. Apolipoprotein A-II (A-II) did not increase with age in men (r = -0.20, n = 172), but showed a slight increase with age in women (0.1 mg/dl per yr, r = 0.20, n = 188). A-II correlated significantly with apolipoprotein A-I (A-I) (r = 0.71) and high density lipoprotein (HDL) cholesterol (men, r = 0.64; women, r = 0.49). The A-I/A-II ratio was significantly related to HDL cholesterol (men, r = 0.29; women, r = 0.44). Women on no medication (n = 92) had A-II levels similar to men (34+/-5 and 33+/-5 mg/dl, mean+/-SD, respectively), whereas women on oral contraceptives or estrogens had significantly higher levels (39+/-6 mg/dl, n = 75, P < 0.01). The plasma A-I/A-II weight ratio was 3.6+/-0.4 for men and 3.8+/-0.5 for women. In the d = 1.10-1.21 subfraction, both males and females had similar A-I, A-II, and HDL cholesterol levels (men: mean, 97, 27, and 32 mg/dl, respectively; women: mean, 104, 28, and 36 mg/dl, respectively). Women had approximately twice the amount of A-I, A-II, and HDL cholesterol than men in the d = 1.063-1.10 fraction (men: mean, 10, 2, and 10 mg/dl, respectively; women: mean, 24, 4, and 19 mg/dl, respectively). The A-I/A-II weight ratio in the d = 1.063-1.10 fraction (men, 5.1+/-0.7; women, 6.1+/-1.3) was significantly greater (P < 0.01) than that in the d = 1.10-1.21 fraction (men, 3.7+/-0.2; women, 3.8+/-0.2). Furthermore, the weight ratio of cholesterol to total apoprotein A in the d = 1.063-1.10 fraction (men, 0.75+/-0.09; women, 0.67+/-0.05) was significantly higher (P < 0.01) than that found in the d = 1.10-1.21 fraction (men, 0.26+/-0.04, women, 0.28+/-0.05). Thus, the compositions of HDL hydrated density subclasses are significantly different from each other. These results suggest that the differences in HDL between men and women are due primarily to differences in the relative proportions of HDL subclasses rather than to the intrinsic differences in HDL structure.  相似文献   
39.
Kimura's disease is a rare chronic inflammatory disorder with a high rate of recurrence. The clinical and imaging features of Kimura's disease have been documented in the literature, but the relationship between these features and disease recurrence is still unclear. We conclude that disease duration of greater than 5 years, bilateral involvement, a lesion diameter of greater than 3 cm, a blood eosinophil count greater than 20%, and ill-defined lesions are predictive factors for the recurrence of Kimura's disease.  相似文献   
40.
OBJECTIVE: To evaluate the association between trauma team activation according to well-established protocols and patient survival. METHODS: Single centre, registry study of data collected prospectively from trauma patients (who were treated in a trauma resuscitation room, who died or who were admitted to ICU) of a tertiary referral trauma centre Emergency Department (ED) in Hong Kong. A 10-point protocol was used to activate rapid trauma team response to the ED. The main outcome measures were mortality, need for ICU care, or operation within 6h of injury. RESULTS: Between 1 January 2001 and 31 December 2005, 2539 consecutive trauma patients were included in our trauma registry, of which 674 patients (mean age 43 years, S.D. 22; 71% male; 94% blunt trauma) met trauma call criteria. Four hundred and eighty two (72%) correctly triggered a trauma call, and 192 (28%) were not called ('undercall'). Patients were less likely to have a trauma call despite meeting criteria if they were aged over 64 years, had sustained a fall, had a respiratory rate <10 or >29 per minute, a systolic blood pressure between 60 and 89 mm Hg, or a GCS of 9-13. In a sub-group of moderately poor probability of survival (probability of survival, P(s), 0.5-0.75), the odds ratio for mortality in the undercall group compared with the trauma call group was 7.6 (95% CI, 1.1-33.0). CONCLUSIONS: In our institution, undercalls account for 28% of patients who meet trauma call criteria and in patients with moderately poor probability of survival undercall is associated with decreased survival. Although trauma team activation does not guarantee better survival, better compliance with trauma team activation protocols optimises processes of care and may translate into improved survival.  相似文献   
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