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91.

Aim

Compare the diagnostic accuracy of surgeon performed ultrasound to radiology performed ultrasound in children presenting with suspected appendicitis to a tertiary care pediatric hospital in Australia.

Methods

Children under 16 presenting to the emergency department of The Children's Hospital at Westmead were considered for the study. Patients with obvious signs of appendicitis not requiring ultrasound and those with established ultrasound diagnosis of appendicitis were excluded. Ultrasound was performed by a Pediatric Surgeon (SPU) after obtaining consent. The treating team was blinded to the results. Patient underwent formal ultrasound in radiology (RPU) and treatment was based on the formal report. SPU result was reviewed by a radiologist blinded to results of RPU. The results were compared.

Results

65 children underwent ultrasound. 35 were male. Median age was 10 (range3–15). Median weight was 36 kg (range 12.6–76.2 kg), z-score median 0.21 (? 1.83 to 2.74). Symptom duration ranged from few hours to 2?weeks but majority (45) had symptoms for less than 48?h. Prevalence of appendicitis was 45%. Thirty two underwent surgery. Negative appendicectomy rate was 9.4%. Thirty three did not have surgery. 8 represented but only one proceeded to appendicectomy. SPU was done earlier than RPU (median 12?h vs 14.15?h) p?=?0.088. Diagnostic accuracy using ROC did not reveal significant difference.

Conclusion

SPU can be performed earlier than RPU with reliable accuracy. Training surgical trainees will enable early diagnosis and management of appendicitis.  相似文献   
92.
93.

Introduction  

The benefits of higher positive end expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) have been modest, but few studies have fully tested the "open-lung hypothesis". This hypothesis states that most of the collapsed lung tissue observed in ARDS can be reversed at an acceptable clinical cost, potentially resulting in better lung protection, but requiring more intensive maneuvers. The short-/middle-term efficacy of a maximum recruitment strategy (MRS) was recently described in a small physiological study. The present study extends those results, describing a case-series of non-selected patients with early, severe ARDS submitted to MRS and followed until hospital discharge or death.  相似文献   
94.
A cell line with immature blast cell morphology was isolated from HL-60 promyelocytic leukemia cell cultures and designated HL-T. This new cell type is biphenotypic, expressing terminal transferase (TdT) together with myelomonocytoid immunologic features. TdT enzymatic activity, undetectable in HL-60, was determined to be 140 to 180 units/10(8) HL-T cells by the dGTP-assay, approximately 20% of the activity found in lymphoblastoid cell lines. HL-T predominantly synthesize the known 58- kDa TdT-protein plus a minor 54/56-kDa doublet. The 58-kDa steady state form is nonglycosylated and is phosphorylated. Precursor antigens S3.13 and MY-10, absent on HL-60, are expressed by HL-T; however, the cells are negative for HLA-Dr. Southern blot analysis by hybridization with immunoglobulin heavy chain (JH) and T cell-receptor chain gene (T beta) probes shows JH to be in the germ-line configuration in both cell lines and the T beta gene to be in germ-line in HL-60 but to be rearranged in HL-T. Truncation of the gene encoding the granulocyte-macrophage-colony- stimulating factor (GM-CSF), as found in HL-60, is not observed in HL- T. HL-T are resistant to differentiation-induction by retinoic acid and 1,25-dihydroxyvitamin D3. Cytogenetically HL-T share with HL-60 a deletion of the short arm of chromosome 9 at breakpoint p13, an aberration frequently found in patients with T cell leukemia. In addition, HL-T display t(8;9)(p11;p24) and trisomy 20. Tetraploidy is observed in 80% of HL-T metaphases with aberrations identical to those in the diploid karyotype. Like HL-60, the new line shows some surface- antigenic-T cell characteristics. Despite an antigenic pattern most consistent with that of helper-inducer T cells (T4+, D44+/-, 4B4+, 2H4- , TQ1+/-), HL-T cells and their conditioned culture medium suppress antigen, mitogen, and mixed-leukocyte-culture-mediated lymphocyte proliferation.  相似文献   
95.

Background  

Current health policies assume that prescribing is more efficient and rational when general practitioners (GPs) work with a formulary or restricted drugs lists and thus with a limited range of drugs. Therefore we studied determinants of the range of drugs prescribed by general practitioners, distinguishing general GP-characteristics, characteristics of the practice setting, characteristics of the patient population and information sources used by GPs.  相似文献   
96.
I-compounds are endogenous bulky DNA modifications which are detected by nuclease P1-enhanced 32P-post-labeling in tissue DNA of animals not knowingly exposed to carcinogens. Their profiles and levels depend inter alia on animal age, species, strain, tissue, gender, diet and exposure to chemicals such as cytochrome P450 inducers and carcinogens. Due to lack of sufficient material obtainable from in vivo sources, chemical structures of I-compounds and their parent normal bases have not yet been identified. In this report we provide 32P-post-labeling and chromatographic evidence that two prominent I-compounds, herein called C1 and C2, which occur at relatively high levels in pig liver DNA are guanine derivatives. This result was obtained by showing that both compounds, isolated from 32P-post-labeling thin-layer maps, were chemically unstable, i.e. they could be readily hydrolyzed to 32P-post- labeled deoxyguanosine 3',5'-bisphosphate by heating in water. C1 appeared particularly labile, undergoing hydrolysis during thin-layer chromatography at pH 3.3 without heating. Several other I-compounds and adducts, as well as the four normal DNA nucleotides, were, however, highly resistant to hydrolysis under the conditions used here. The possible significance of these findings will be briefly discussed.   相似文献   
97.
The aim was to establish the prevalence of pulmonary embolism in 21 children (median age 12 months; range 5-132 months) with central venous lines in situ > 3 months (median 10 months; range 3-47). Twelve-lead electrocardiograms (ECGs) and echocardiograms were analysed in a retrospective study using ECG and echocardiographic criteria for pulmonary embolism-previously established and validated in adult patients- and standard paediatric ECG values as control data. Patients were scored as having definite (n = 7), probable (n = 5), or no pulmonary embolism (n = 9). Overall 57% of ECGs showed abnormalities compatible with pulmonary embolism. In two patients, serial ECGs obtained during an acute cardiorespiratory illness showed cumulative changes diagnostic of pulmonary embolism. Eight of 12 patients with abnormal ECGs had echocardiography; in seven of these (88%) the right ventricular end diastolic diameter was > 2SD above the mean value for age. Twelve of the patients included in this study have died; two died following an acute respiratory illness. There was postmortem evidence of pulmonary thromboembolism in both of the two children for whom necropsy information was available. The data suggest that pulmonary embolism is common in children who have central venous lines in situ for > 3 months. Serial studies are of value in some patients. Pulmonary embolism may compromise the long term survival of children with small bowel failure and preclude consideration for liver and small bowel transplantation.  相似文献   
98.
Intervention to avoid the prone sleeping position during infancy has occurred in various countries after evidence that it increases the risk of sudden infant death syndrome (SIDS). This study examined cohort data to determine if correlates of the prone position differed by period of birth, before intervention (1 May 1988 to 30 April 1991) compared with after intervention (1 May 1991 to 30 April 1992). The usual prone sleeping position was more closely associated with the following factors after intervention: teenage motherhood, low maternal education, paternal unemployment, unmarried motherhood, non-specialist antenatal care, not reading books to prepare for a baby, poor smoking hygiene, and bottle feeding. For example, the association of usual prone position with being unmarried shown by the odds ratio (95% confidence interval) was 0.54 (0.47 to 0.63) in the period before intervention and 1.92 (1.18 to 3.15) in the period after intervention. The alteration in correlates of the prone position reported here provide an example to support the theoretical concept that well known 'modifiable' risk factors for disease tend to be associated with each other in both populations and individuals. This phenomenon was not evident in the population before intervention, that is, before the prone sleeping position became a well known SIDS risk factor.  相似文献   
99.
Twin and singleton growth patterns compared using US   总被引:1,自引:0,他引:1  
Sonography has been used widely in the evaluation of singleton fetal growth. Twin gestations, however, have received less careful attention. In a statistical study of 103 twin pregnancies, the growth patterns of twin biparietal diameter (BPD), fetal femur length (FFL), and abdominal circumference (AC) were compared with those of singletons. The results of the study revealed a decrease in twin BPD growth after 31 to 32 weeks of gestation relative to singletons. Twin AC growth rate decreases after 32-33 weeks of gestation relative to singletons, but the twin FFL growth pattern does not deviate from that of singletons throughout gestation. Because of the significant difference in growth patterns of BPD and AC between twins and singletons in our population, new growth charts for twin BPD and AC are proposed.  相似文献   
100.
The aim of this study was to determine the regional control rate with concurrent chemoradiotherapy (CRT) based on pretreatment nodal size in mucosal head and neck squamous cell carcinoma (HNSCC) in patients who achieved a complete response (CR) at the primary site by 12 weeks post‐treatment. Between December 1997 and November 2003, 117 patients with node‐positive HNSCC were treated with concurrent CRT, with 108 (92%) achieving a CR at the primary site by 12 weeks. There were 93 males (86%), median age 55 (37–79) years and the most common primary site was the oropharynx (65%). Patients were divided into three subgroups: ≤3.0 cm 70 (65%), 3.1–6.0 cm 30 (28%) and ≥6.1 cm 8 (7%). All patients received concurrent platinum‐based chemotherapy and the median radiation dose was 70 Gy (60–72 Gy). The 3‐year regional control rate based on pretreatment nodal size was ≤3.0 cm 88% (95% confidence interval (CI) 78–94%), 3.1–6.0 cm 72% (95%CI 49–86%) and ≥6.1 cm 50% (95%CI 15–77%) (P = 0.001). The 3‐year regional control rate based on pre‐treatment nodal size was ≤3.0cm 88% (95%CI 78–94%), 3.1–6.0 cm 72% (95%CI 49–86%) and ≥6.1 cm 50% (95%CI 15–77%) (P = 0.001). These results provide a quantitative guide for the clinician as to the likelihood of regional control based on pretreatment nodal size following CRT in patients who achieve a CR at the primary site by 12 weeks post‐treatment.  相似文献   
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