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991.
The monomer isosorbide diacrylate (iSDA) and commercially available dithiols allowed access to a range of biosourced, degradable polymers. Altering the dithiol identity significantly affected the glass transition Tgs of the polymer products; however, polymers did not exhibit Tgs above room temperature. Incorporating the comonomer N,N′‐methylene bisacrylamide provided mechanical reinforcement through hydrogen bonding, resulting in soft, pliable materials. Differential scannin calorimetry (DSC) and variable‐temperature fourier‐transform infrared (FTIR) spectroscopy indicated that increases in mechanical integrity resulted from hydrogen bonding. Dynamic mechanical analysis (DMA) revealed materials that exhibited suitable moduli and service windows at body temperature. Biological evaluation demonstrated favorable cytotoxicity and cell attachment, rendering these materials potential candidates as novel scaffold materials for tissue growth.  相似文献   
992.

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   
993.
Therapy for symptoms in the carcinoid syndrome   总被引:1,自引:0,他引:1  
The clinical course and results of drug treatment for manifestations of the carcinoid syndrome are reviewed in 63 patients. The five-year actuarial survival in this group of patients was 48 per cent. The only markers of a poor prognosis that could be identified at diagnosis were marked weight loss and a high (over 1000 mumol/day) 5-hydroxyindole acetic acid excretion. The relative effectiveness of well-established drugs that either block 5-hydroxytryptamine synthesis or block 5-hydroxytryptamine receptors is reported, with respect to the different manifestations of the syndrome, and compared with a small group of patients treated with long-acting somatostatin analogue. In over one-third of patients, primary tumours were not detected on initial investigation, and in none of these did symptoms referrable to the primary site become apparent later.  相似文献   
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Exposure of skin chamber granulation tissue vessels in nondiabetic rats to 11 or 15 mM D-glucose (but not L-glucose or 3-O-methylglucose) twice daily for 10 d induces vascular functional changes (increased albumin permeation and blood flow) identical to those in animals with mild or severe streptozotocin diabetes, respectively. These vascular changes are strongly linked to increased metabolism of glucose via the sorbitol pathway and are independent of nonenzymatic glycosylation as well as systemic metabolic and hormonal imbalances associated with the diabetic milieu. (J. Clin. Invest. 1990. 85:1167-1172.)  相似文献   
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