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1.
Failure of patient-triggered ventilation in very immature infants may be due to the use of inappropriate triggering systems. Two types of airflow trigger were therefore compared consecutively to an airway pressure (SLE) triggering system. Each comparison was made in 10 infants, ≤28 weeks of gestation. Comparison was made of the delivered volume, trigger performance and blood gases using each system for 1 h. Both comparisons showed that the airflow triggering systems performed better: one (Draeger Babylog 8000) had a higher sensitivity ( p < 0:01) and the other (Bird VIP airflow trigger), in which inflation was terminated by sensing a reduction in inspiratory flow, had a lower degree of asynchrony ( p < 0:01) and a tendency to deliver higher volumes. These results suggest that triggering systems sensing airflow changes may be superior to those sensing airway pressure changes in very immature infants. The use of a mechanism to synchronize the termination of inflation to the end of the patient's inspiration may offer further advantages.  相似文献   
2.
Sjogren's syndrome (SS) is an exocrinopathy characterized by T cell infiltrates, salivary gland epithelial cell (SGEC) apoptosis and high Fas and FasL expression. To address the participation of T cell-derived cytokines and of Fas apoptotic pathway in SS glandular lesions, we utilized non-neoplastic SGEC lines established from SS patients and controls. Possibly attesting to their intrinsic activation, cell lines derived from SS patients displayed significantly higher constitutive Fas and FasL than controls. Surface co-expression of Fas and FasL was not associated with spontaneous fratricide apoptosis. SGEC were resistant to anti-Fas-mediated apoptosis (possibly owing to the constitutive expression of anti-apoptotic proteins cFLIP and Bcl-2), but became sensitive after protein or RNA synthesis inhibition. IFN-gamma and TNF-alpha were able to upregulate surface Fas and FasL, whereas IL-1beta downregulated surface FasL. IFN-gamma (but not several other cytokines) reduced the survival of SGEC in a dose- and time-dependent manner and induced Fas/FasL-mediated apoptosis, directly and via anoikia. Dexamethasone inhibited the upregulation of Fas and FasL by IFN-gamma and the induction of SGEC apoptosis and detachment by anti-Fas mAb or IFN-gamma. Our findings indicate the injurious role of IFN-gamma for the salivary epithelia of SS patients through the induction of Fas-mediated apoptosis and anoikia.  相似文献   
3.
The aim of this study was the immunolocalization of transitional cell carcinoma of the bladder with a radiolabelled murine tumour-associated monoclonal antibody and the measurement of the absolute uptake of the antibody by the tumour. Fourteen patients with transitional cell carcinoma of the bladder received 3–6 mCi (111–222 MBq) of technetium-99m labelled HMFG1 monoclonal antibody intravesically and one patient, 2 mCi (74 MBq) of iodine-131 labelled 11.4.1, which is a non-tumour-specific monoclonal antibody. Four of the 15 patients were evaluated with singlephoton emission tomography (SPET) 1 1/2 to 2 h post administration. All patients underwent transurethral resection of the bladder tumour within 12–20 h following intravesical administration of the radiolabelled antibody. The radioactivity of biopsy specimens from normal urothelium and tumour areas were counted in a gamma counter. The mean uptake of the radiolabelled antibodies from normal and tumour sites was expressed as a percentage of the administered dose per kilogram of tissue. Conventional histology and immunohistochemistry using HMFGI monoclonal antibody were performed on paraffin sections of the biopsy specimens. Although our results are preliminary, it can be concluded that: (a) bladder tumours are well imaged by SPET when using99mTc-HMFG1; (b) intravesically administered radiolabelled antibody remains on the bladder tissue and does not escape into the systemic circulation; (c) the wide range of tumour uptake values (0%–9.3% administered dose/kg) observed probably can be attributed to heterogeneity of the antigenic expression of the tumour; (d) values of99mTc-HMFGI monoclonal antibody uptake by the tumour do not justify future attempts at radioimmunotherapy.  相似文献   
4.
Infants born prematurely who develop chronic lung disease (CLD) have airways obstruction and hence may have low lung volume. The aim of this study was to test that hypothesis and ascertain whether the nature of the comparison control group influenced the results. Sixteen infants who were oxygen dependent for more than 28 days (CLD) and eight infants without CLD had measurements of functional residual capacity (FRC) at 14 and 28 days. The 16 CLD infants consisted of eight less than 27 weeks gestational age (group A) and eight greater than 26 weeks gestational age (group B). The eight infants without CLD (group C) were each matched for gestational age and gender to infants in group B. Group A compared to group C had lower FRCs both at 14 days (median 18 ml/kg vs 27 ml/kg, P<0.01) and 28 days (median 20 ml/kg vs 26 ml/kg, P<0.05), but group A differed from group C with respect to both gestational age (P<0.01) and birth weight (P<0.01). The FRC results of group B were lower than those of their matched controls (group C) only at 28 days (median 22 vs 26 ml/kg, P<0.05). Overall, the FRC results at 14 and 28 days correlated significantly with the duration of oxygen and ventilator dependence and weakly with gestational age. Conclusion These results support the hypothesis that FRC results are lower in infants with CLD compared to those without CLD when measured in the neonatal period and emphasize the importance of an appropriate control group. Measurement of lung volume may facilitate assessment of the response to therapies for CLD. Received: 5 May 1997 / Accepted in revised form: 29 September 1997  相似文献   
5.
6.
The objective of this article is to report 7 previously unpublished uterine rupture cases in pregnancy after laparoscopic myomectomy and to update the medical literature. All cases were reported to the Board of Endoscopic Gynecologic Surgery (Athens, Greece) from 1998 to 2011. Myomas were single in 85.7% of patients, subserosal or pedunculated in 85.7%, and ≤5 cm in 71.4%. Bipolar diathermy was the sole method used for hemostasis in 28.6%, and could be characterized as excessive in 85.7%. A 2-layer closure with stitches of the myometrium was performed in just 14.3% of cases. Mean (SD) time between surgery and pregnancy was 1.4 (0.5) years. Uterine rupture occurred at 34 weeks of gestation or later in 85.7%, and during labor in 14.3% of cases. All women survived. Fetal demise was reported in 1 twin pregnancy (both fetuses) with rupture at 24 weeks of gestation. Laparoscopic myomectomy should be performed by adequately trained and experienced surgeons. Excessive use of diathermy for hemostasis should be avoided, and multiple-layer suturing should always be used for repairing the myometrial defect in cases of intramural and subserosal myomas with deep intrusion.  相似文献   
7.
Comparative study is performed between echocardiographic measurements (TM), exercise test blood pressure profile (ETP) and ambulatory blood pressure load (BPL) in 26 borderline hypertensive subjects (19 males, 7 females). An abnormal ETP is found for 15 subjects (57 p. 100), an abnormal BPL for 10 subjects (38 p. 100). The diastolic interventricular septum thickness (IVS) and the diastolic posterior wall thickness (PWT) are abnormal (greater than 11 mm) for 6 and 3 subjects. Patient with pathologic ETP or/and BPL have greater IVS and PWT than other subjects (p less than 0,001). A good correlation is found between individual activity systolic blood pressure or 24 hours systolic blood pressure means values and PWT, IVS or left ventricular mass. These 3 examinations lead to a better assessment of cardiovascular strain and allow a better diagnosis and therapeutic approach in borderline hypertensive patients.  相似文献   
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9.
This study investigated the development of novel metaphor and metonymy comprehension in both typically developing (TD) children and individuals with Williams syndrome (WS). Thirty-one TD children between the ages of 3;09 and 17;01 and thirty-four individuals with WS between the ages of 7;01 and 44 years old were administered a newly developed task examining novel metaphor and metonymy comprehension, as well as a range of standardised tests that assess semantic knowledge. This age range and the background measures allowed construction of developmental trajectories to investigate whether chronological age or mental age, represented by word knowledge, relate to novel metaphor and metonymy comprehension. The results showed that comprehension of figurative language did not increase with chronological age in WS, in contrast to TD. Although there was no difference for the different types of metaphors, certain metonymy expressions were found to be easier than others in the TD group. In addition, semantic knowledge was a reliable predictor for novel metaphor and metonymy comprehension in the TD but only for metonymy in the WS group. In sum, development of novel metonymy in the WS group is only delayed while comprehension of novel metaphor is both delayed and atypical. However, future research should further investigate differences between sub-types, as well as what cognitive factors relate to novel metaphor comprehension in individuals with Williams syndrome.  相似文献   
10.
Neurological Sciences - Acute encephalopathy is a widely used term, implying a rapidly progressive multifocal or diffuse brain dysfunction, caused by acute structural disturbance or a myriad of...  相似文献   
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