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61.
A telecare system (Medic4All) has been developed that relies on a wireless wristwatch-like sensor to measure the pulse wave from the radial artery. From this, the heart rate and respiration rate are derived. The system's performance was examined by comparing the results obtained from the pulse wave signal with those obtained from conventional electrocardiographic and spirometer devices. A total of 144 patients participated in the study; their mean (SD) age was 43 (18) years. There were 44 cardiac patients in group 1 and 100 healthy patients, who were studied in their homes, in group 2. There was a significant correlation between the heart rates measured by the two monitoring methods. A 'difference versus average' analysis showed that the error distribution had a mean (SD) value of -0.1 (3.3) beats/min. Similarly, the respiration rates measured by the two techniques were significantly correlated. The error distribution had a mean (SD) value of 0.1 (1.9) respirations/min. The present study suggests that the wrist-worn sensor represents a promising tool for online detection and monitoring of vital signs in the home.  相似文献   
62.
OBJECTIVE: Cardiac surgery patients might have a higher incidence of difficult laryngoscopy than the general population because of older age, dental problems, and obesity. The authors estimated the incidence and predictors of difficult laryngoscopy in coronary artery bypass surgery patients. DESIGN: Prospective, controlled study. SETTING: University setting. PARTICIPANTS: Patients undergoing coronary artery bypass or general surgery. INTERVENTIONS: Two hundred consecutive patients undergoing coronary artery bypass graft and 444 general surgery patients, all aged >40 years, were compared for the incidence and predictors of difficult laryngoscopy, defined as a grade III or IV view. MEASUREMENTS AND MAIN RESULTS: Predictors of difficult laryngoscopy were considered mouth opening <4 cm, limited cervical mobility, thyromental distance <6 cm, protruding or partially missing upper teeth, and Mallampati classes 3 and 4. More cases of difficult laryngoscopy were recorded in cardiac patients (10% v 5.2%, p <0.023). The cardiac patients were older, mostly men, and belonged to ASA III-IV risk classes. Mallampati classes 3 and 4 were more frequent in the control group. With univariate analysis, difficult laryngoscopy correlated with 7 variables: older age, ASA-IV risk class, protruding or partially missing upper teeth, limited mouth opening, limited neck movement, thyromental distance <6 cm, and diabetes mellitus. Multivariate analysis adjusted for propensity score identified older age (odds ratio = 1.05/yr, 95% confidence interval = 1.005-1.09, p < 0.03) and limited neck movement (odds ratio = 9.5, 95% confidence interval = 2.2-41, p < 0.003), but not cardiac surgery per se, as independent predictors of difficult laryngoscopy. CONCLUSIONS: Difficult laryngoscopy was more frequent in cardiac surgery patients (10% v 5.2%). Older age and limited neck movement, but not cardiac surgery per se, were independent predictors of difficult laryngoscopy.  相似文献   
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Within a 2 month period 131 Ethiopian immigrants were admitted for treatment at a general hospital in Jerusalem. There were 52 patients with malaria, 13 with typhoid fever, 24 with pneumonia, seven with tuberculosis, nine with shigella and 11 with campylobacter. Over three-quarters of these patients were anaemic. In the majority of cases anaemia was normocytic and was most probably secondary to malaria and other intercurrent infections. The prevalence of diffuse non-toxic goitre was 7% in children and 19% in adults with a male to female ratio of 4:13. A positive rapid plasma reagin (RPR) test was found in 4% of sera tested and a positive HBsAg in 13%. IgG antibodies to HBc antigen were found in 75% of subjects. All patients with infectious diseases responded to therapy and, despite their poor condition at arrival, there were no fatalities and no late sequelae. The high HBsAg carrier state calls attention to the risk of vertical transmission by infected mothers and underlines the need for active immunization of infants at risk. The high prevalence of untreated tuberculosis and malaria poses a potential public health hazard, but with the current systematic screening of this population leading to identification and effective treatment of affected subjects, chances for the practical eradication of malaria and tuberculosis are excellent. Finally, the large scale transfer of a population from rural Africa to a modern and largely urban society presents a unique opportunity for a prospective study of the impact of environment on the emergence of diseases which plague modern society such as diabetes, atherosclerotic cardiovascular disease, hypertension and cancer.  相似文献   
66.
Our improved toluidine blue-DNA agar was compared with methyl green DNase test agar for the detection of DNA hydrolysis by campylobacters. The toluidine blue-DNA agar gave clear-cut positive and negative reactions with campylobacter strains belonging to several species.  相似文献   
67.
Several GTP-binding proteins (G-proteins) undergo post-translational modifications (isoprenylation and carboxyl methylation) in pancreatic beta cells. Herein, two of these were identified as CDC42 and rap 1, using Western blotting and immunoprecipitation. Confocal microscopic data indicated that CDC42 is localized only in islet endocrine cells but not in acinar cells of the pancreas. CDC42 undergoes a guanine nucleotide-specific membrane association and carboxyl methylation in normal rat islets, human islets, and pure beta (HIT or INS-1) cells. GTPgammaS-dependent carboxyl methylation of a 23-kD protein was also demonstrable in secretory granule fractions from normal islets or beta cells. AFC (a specific inhibitor of prenyl-cysteine carboxyl methyl transferases) blocked the carboxyl methylation of CDC42 in five types of insulin-secreting cells, without blocking GTPgammaS-induced translocation, implying that methylation is a consequence (not a cause) of transfer to membrane sites. High glucose (but not a depolarizing concentration of K+) induced the carboxyl methylation of CDC42 in intact cells, as assessed after specific immunoprecipitation. This effect was abrogated by GTP depletion using mycophenolic acid and was restored upon GTP repletion by coprovision of guanosine. In contrast, although rap 1 was also carboxyl methylated, it was not translocated to the particulate fraction by GTPgammaS; furthermore, its methylation was also stimulated by 40 mM K+ (suggesting a role which is not specific to nutrient stimulation). AFC also impeded nutrient-induced (but not K+-induced) insulin secretion from islets and beta cells under static or perifusion conditions, whereas an inactive structural analogue of AFC failed to inhibit insulin release. These effects were reproduced not only by S-adenosylhomocysteine (another methylation inhibitor), but also by GTP depletion. Thus, the glucose- and GTP-dependent carboxyl methylation of G-proteins such as CDC42 is an obligate step in the stimulus-secretion coupling of nutrient-induced insulin secretion, but not in the exocytotic event itself. Furthermore, AFC blocked glucose-activated phosphoinositide turnover, which may provide a partial biochemical explanation for its effect on secretion, and implies that certain G-proteins must be carboxyl methylated for their interaction with signaling effector molecules, a step which can be regulated by intracellular availability of GTP.  相似文献   
68.
Severe pulmonary barotrauma occurred following smoke and toxic gas inhalation in a 20-year-old male. He developed pneumothorax, pneumomediastinum, and extensive facial subcutaneous emphysema which intensified during treatment with positive pressure ventilation. Following the appearance of diplopia and exotropia, orbital emphysema was demonstrated radiologically. The diplopia and exotropia were manifestations of mechanical interference in extra-ocular muscle function by the intra-orbital air, an unusual expression of pulmonary barotrauma.  相似文献   
69.

Importance

Appendicitis is a common, potentially serious pediatric disease. An important factor in determining management strategy [whether/when to perform appendectomy, duration of antibiotic therapy/hospitalization, etc.] and predicting outcome is distinguishing whether perforation is present.

Objective

The objective was to determine efficacy of commonly assessed pre-operative variables in stratifying perforation risk in children with appendicitis.

Design

A retrospective analysis of consecutive cases was performed.

Setting

The setting was a large urban hospital pediatric emergency department.

Participants

Four hundred forty-eight consecutive cases of CT [computerized tomography]-confirmed pediatric appendicitis during a 6-year period in an urban pediatric ED [emergency department]: 162 with perforation and 286 non-perforated.

Main outcome(s) and measure(s)

To determine efficacy of clinical and laboratory variables with distinguishing perforation outcome in children with appendicitis.

Results

Regression analysis identified 3 independently significant variables associated with perforation outcome – and determined their ideal threshold values: duration of symptoms > 1 day; ED-measured fever [body temperature > 38.0 °C]; CBC WBC absolute neutrophil count > 13,000/mm3. The resulting multivariate ROC [receiver operating characteristic] curve after applying these threshold values gave an AUC [area under curve] of 89% for perforation outcome [p < 0.001]. Risk for perforation was additive with each additional predictive variable exceeding its threshold value, linearly increasing from 7% with no variable present to 85% when all 3 variables are present.

Conclusions

A pre-operative scoring system comprised of 3 commonly assessed clinical/laboratory variables is useful in stratifying perforation risk in children with appendicitis.Physicians can utilize these factors to gauge pre-operative risk for perforation in children with appendicitis, which can potentially aid in planning subsequent management strategy.

Level of evidence

III.  相似文献   
70.
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