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81.
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   
82.
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   
83.
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   
84.
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   
85.
Several lines of evidence suggest that the amygdala and the bed nucleus of the stria terminalis (BNST) are differentially involved in phasic and sustained fear. Even though, results from neuroimaging studies support this distinction, a specific effect of a temporal dissociation with phasic responses to onset versus sustained responses during prolonged states of threat anticipation has not been shown yet. To explore this issue, we investigated brain activation during anticipation of threat in 38 healthy participants by means of functional magnetic resonance imaging. Participants were presented different visual cues indicated the temporally unpredictable occurrence of a subsequent aversive or neutral stimulus. During the onset of aversive versus neutral anticipatory cues, results showed a differential phasic activation of amygdala, anterior cingulate cortex (ACC), and ventrolateral prefrontal cortex (PFC). In contrast, activation in the BNST and other brain regions, including insula, dorsolateral PFC, ACC, cuneus, posterior cingulate cortex, and periaqueductal grey was characterized by a sustained response during the threat versus neutral anticipation period. Analyses of functional connectivity showed phasic amygdala response as positively associated with activation, mainly in sensory cortex areas whereas sustained BNST activation was negatively associated with activation in visual cortex and positively correlated with activation in the insula and thalamus. These findings suggest that the amygdala is responsive to the onset of cues signaling the unpredictable occurrence of a potential threat while the BNST in concert with other areas is involved in sustained anxiety. Furthermore, the amygdala and BNST are characterized by distinctive connectivity patterns during threat anticipation. Hum Brain Mapp 37:1091–1102, 2016. © 2015 Wiley Periodicals, Inc .  相似文献   
86.
A questionnaire to determine patterns of neonatal red cell transfusion practice during 1985 was mailed to 2200 blood banks of American Association of Blood Banks (AABB) institutional members and children's hospitals. There were 915 responses (41.6%); 785 responses (86%) contained sufficient data for analysis. The majority (70.6%) of 785 responding hospitals were community/urban institutions. However, more highly specialized, pediatric hospitals were also represented by 92 university/tertiary-care hospitals (11.7% of respondents) and 29 children's hospitals (3.7% of respondents). Two-thirds of hospitals performed a major antiglobulin crossmatch (rather than an abbreviated one) before all neonatal red cell transfusions. The red cell preparation most frequently selected for small-volume transfusions was ABO and Rh group-specific red cell concentrates. When performing only large-volume exchange transfusions, 19.2 percent of hospitals used whole blood; all others prepared reconstituted units of red cells plus fresh-frozen plasma, a practice that frequently causes exposure to two donors per unit. Another practice likely leading to multiple donor exposure is the use of fresh-frozen plasma to adjust the hematocrit of red cell preparations to a predetermined value prior to a small-volume transfusion. Over one-half of hospitals adjusting hematocrits used plasma, presumably from one donor, to dilute packed red cells from another donor, a practice that has no apparent medical benefit. Most hospitals (63.4%) provided red cells with a reduced risk of transmitting cytomegalovirus; blood from seronegative donors was selected by 65 percent of hospitals. The majority of hospitals, including most of the community/urban hospitals, did not irradiate blood products before transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.

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   
88.
The ability to store platelets beyond 24 hours requires a functionally closed system. This study tested the ability of a cell separator bowl seal system to resist penetration of microbial contamination under normal running conditions and under extreme environmental stress. Three test organisms, Micrococcus luteus, Serratia marcescens, and Staphylococcus epidermidis, were applied directly to the bowl at the edge of the seal or aerosolized and passed through the centrifuge chamber while the cell separator was run through a simulated platelet collection. A sterile, bacteriologic nutrient medium was perfused through the tubing set, thus simulating the flow of blood fractions. Following the procedure, the medium was examined for microbial growth. The concentration of aerosolized bacteria ranged from 5.2 x 10(1) to 3.9 x 10(3) colony-forming units (CFU) per mL, and the concentration of bacteria applied to the edge of the seal ranged from 1.9 x 10(5) to 2.8 x 10(9) CFU per mL. The positive control, direct inoculation of S. marcescens into the circulating medium (50 CFU/500 mL), resulted in recovery of the identical organism after 24 hours' incubation. No contamination of the system was detected in 40 experiments with aerosolized bacteria or in 32 experiments in which bacteria were applied directly to the seal. This study demonstrates that this sealed-bowl system resists microbial contamination.  相似文献   
89.
高剂量地塞米松为多发性骨髓瘤常用治疗方案。本研究比较了高、低剂量地塞米松分别联合来那度胺治疗多发性骨髓瘤的临床疗效及毒副作用。  相似文献   
90.
Movement artifacts are still considered a problematic issue for imaging research on overt language production. This motion-sensitivity can be overcome by functional near-infrared spectroscopy (fNIRS). In the present study, 50 healthy subjects performed a combined phonemic and semantic overt verbal fluency task while frontal and temporal cortex oxygenation was recorded using multi-channel fNIRS. Results showed a partial dissociation for phonemic and semantic word generation with equally increased oxygenation in frontotemporal cortices for both types of tasks whereas anterior and superior prefrontal areas were exclusively activated during phonemic fluency. Also, a general left-lateralization was found being more pronounced during semantic processing. These findings line up with earlier imaging and lesion studies emphasizing a crucial role of the temporal lobe for semantic word production, whereas phonemic processing seems to depend on intact frontal lobe function.  相似文献   
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