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761.
WB de Carvalho AC Carvalho GL Gurgueira AM Ikeda JH Lee DR Almeida 《Canadian Metallurgical Quarterly》1998,116(1):1602-1605
Five patients with ages ranging from 6 months to 3 years were analyzed. All received inhaled nitric oxide (NO--20 parts per million (ppm)) and oxygen (O2--at a concentration of 90-95%) by means of an oxygen hood. Mean Pulmonary Artery Pressure (MPAP), Mean Aortic Pressure (MAoP), Pulmonary Vascular Resistance (PVR) and Systemic Vascular Resistance (SVR) were measured and the calculation of their relationship to pulmonary/systemic flow (Qp/Qs) was performed by the catheterization of the femoral artery vein. Three patients presented reduction in PVR and increase in Qp/Qs. There were no systemic alterations or any side effect from using NO. 相似文献
762.
BACKGROUND: Current clinical advice regarding peanut allergy is based on small series of patients. OBJECTIVE: To determine, in a large group of peanut allergic subjects, the patterns of clinical severity, symptom progression and availability and use of rescue medications. METHODS: Questionnaire study of 622 self-reported allergic subjects. RESULTS: A total of 406 patients (66%) reported symptoms on contact with peanut. Only 121 (19%) had been knowingly exposed to peanut before the first documented reaction, implying a high frequency of occult sensitization. Severe symptoms were more common in adults. Abdominal symptoms were significantly associated with collapse. Fifty per cent reported reactions in the previous year. Only 82 (13%) had been admitted to hospital because of a reaction. Adrenaline was carried in some form by 65% though only 78 subjects (12.5%) had ever received injected adrenaline. Only 18/43 subjects (41%) who collapsed were given adrenaline. Skin-prick test weal size correlated weakly with severity but there were large overlaps between the groups. Peanut-specific IgE peaked in the teenage group, but did not correlate with severity. CONCLUSIONS: Peanut allergy is characterized by more severe symptoms than other food allergies and by high rates of symptoms on minimal contact. Skin-prick testing and peanut-specific IgE levels do not predict clinical severity. Avoidance of peanut is difficult. Many people suffering severe relations are inadequately treated. Sufferers need education and training in the use of rescue medication. 相似文献
763.
Drowning and near-drowning are major causes of death and neurological damage, respectively, in children. The pathophysiological substrate consists of hypoxia, ischaemia, respiratory and metabolic acidosis and sometimes, hypothermia. Most cases involve aspiration of liquid; this leads to a persistent impairment of the gas exchange. Occurrence of arrhythmias and hypovolaemia is very likely. The main objective of treatment of the near-drowned is limiting cerebral damage. Treatment consists of resuscitation and stabilization, administration of oxygen with positive end-expiratory pressure, intravenous administration of liquids and central reheating. The prognosis depends in the first place on the duration of the submersion, which, however, is often difficult to establish. Submersion for over 5 minutes is prognostically unfavourable. In hypothermia due to submersion in ice cold water the prognostic factors are less clear--in these cases the treatment should always be continued until the core temperature is > or = 32 degrees C. 相似文献
764.
PJ Verschure J Van Marle CJ Van Noorden WB Van den Berg 《Canadian Metallurgical Quarterly》1997,37(4):285-298
The use of immunohistochemical detection techniques and fluorescent molecular probes in light and fluorescence microscopy allows accurate and specific analysis of a great variety of cell and tissue components. However, when staining yields only low intensity levels, serious problems may arise with discrimination of specific signals against background staining. This problem is often inherent with articular cartilage research. Application of confocal laser scanning microscopy (CLSM) can circumvent these problems. The CLSM collects images that are almost free of out-of-focus signals, which results in improved spatial resolution and discrimination as compared with conventional microscopy. Moreover, CLSM allows optical sectioning of specimens and three-dimensional reconstruction of the microscopical object. Quantitative evaluation of microscopical images is hampered by out-of-focus signals because they interfere with specific signals in the image. Interference of these nonspecific signals can be diminished by application of CLSM; in CLSM only one single point in microscopical objects is illuminated at any time and this point is then imaged into the pinhole at the entrance of the photo-detector and subsequently digitized. The present review is a discussion of the present state of the art in digital imaging with the use of CLSM in cartilage research. This discussion includes aspects such as sensitivity, specificity, spatial resolution and accuracy of quantitative analysis in microscopical immunofluorescent objects. 相似文献
765.
Effects of continuous feeding flavonoids (flavone, flavanone, and tangeretin) on drug-metabolizing enzymes in rat liver were investigated to ascertain how long feeding is required to reach maximal induction and to determine whether maximal induction is maintained for a long period of feeding. In the first experiment rats received a diet containing 10 mmol flavonoid/kg dry matter for 4, 8, 16, or 32 d. The second experiment was designed to examine the time course for induction during the first 4 d. The kinetics of induction depended on the chemical structure of the flavonoid and was different from one enzyme to another. Flavone increased P450 1A and P450 2B apoproteins and stimulated many enzyme activities. A significant increase of P450 1A1/2 proteins, ethoxyresorufin O-deethylase (EROD), and methoxyresorufin O-demethylase (MROD) activities occurred as early as 6 h after the first administration, and a gradual increase was observed up to 4 d of feeding. P450 2B1/2 proteins and pentoxyresorufin O-depentylase (PROD) activity were also increased but after a lag period when compared with P450 1A1/2 proteins. EROD and MROD activities declined after 4 d, whereas PROD activity remained steady during 32 d of flavone feeding. Glutathione transferase (GST) and p-nitrophenol UDP-glucuronosyl transferase (UGT) activities were also increased. The maximal induction was reached by 4 d of feeding for UGT and after a longer duration of feeding (16 d) for GST. Flavanone treatment induced mostly P450 2B1/2 proteins and PROD, GST, and UGT activites. After 4 d of feeding, P450 2B1/2 proteins and PROD activity declined whereas GST and UGT activities remained steady. Tangeretin treatment produced changes similar to flavone but of lesser magnitude and after a longer delay. 相似文献
766.
767.
A case of malignant chondroblastoma with metastases is reported. The patient initially presented with a lytic lesion in his left pubic ramus. He was treated with curettage, but the lesion recurred 3 years later. After repeated curettage, radiation therapy, and the late development of multiple bone and soft-tissue metastases, he succumbed to his disease 13 years after diagnosis. The surgical pathology from each of his several procedures was reviewed. Although no definite malignant transformation was apparent, a metastatic deposit curetted 3 months prior to death showed some increase in mitotic activity. Flow cytometry of specimens from the patient's first local recurrence and a late distant metastasis was performed and revealed the interval development of a minor aneuploid peak between the two samples. This fatal chondroblastoma is the only one in our series of 80 patients treated over the past 25 years. 相似文献
768.
AA van Valburg GJ van Osch PM van der Kraan WB van den Berg 《Canadian Metallurgical Quarterly》1996,15(5):181-187
For many years geneticists have relied on conditional activation to study the roles of cytolytic or cytostatic proteins in lower eukaryotes or to elucidate the epistatic relationships of proteins in a signaling pathway. Regardless of their merits, conditional mutants have only been available to mammalian geneticists within the past few years. Moreover, the approaches that exist are still limited to a subset of signaling molecules and are not reliable for in vivo studies. Now, added to the biologist's toolbox is a versatile new approach based on chemically induced dimerization that should allow for the reversible regulation of proteins at the cell surface, intracellularly, in the nucleus and in vivo. 相似文献
769.
MD Eisen DM Yousem KT Montone MJ Kotapka DC Bigelow WB Bilker LA Loevner 《Canadian Metallurgical Quarterly》1996,17(10):1937-1945
PURPOSE: To assess the accuracy of MR imaging in predicting dural, venous sinus, and perineural invasion by skull base tumors. METHODS: The preoperative MR images of 22 patients who had resection of skull base neoplasms were evaluated for the following characteristics: dural enhancement, pial enhancement, local perineural invasion by adjacent tumor, and venous sinus invasion by tumor. The greatest width of dural enhancement was measured, and the character of dural enhancement was noted. The pathologic and surgical reports were reviewed retrospectively with specific attention to dural, venous, and local perineural invasion. RESULTS: Of the 22 patients studied, dural invasion by tumor was confirmed in eight patients, vascular invasion in six patients, and perineural invasion in four patients. The sensitivity of dural enhancement in predicting invasion was 88%, the specificity 50%, and the accuracy 64%. When enhancement and focal nodularity were present, the sensitivity remained at 88%; however, specificity was 100% and accuracy 95%. If the dural enhancement was more than 5 mm thick, sensitivity, specificity, and accuracy were 75%, 100%, and 91%, respectively. Predicting tumor invasion of the dura by the presence of pial enhancement was 50% sensitive and 100% specific. Venous sinus/jugular vein invasion was predicted with 100% sensitivity, 94% specificity, and 95% accuracy. Local perineural invasion was predicted with 100% sensitivity, 50% specificity, and 59% accuracy. CONCLUSIONS: The presence of pial enhancement, focal dural nodules, or dural thickening of more than 5 mm is highly accurate in predicting the presence of neoplastic dural invasion. Linear enhancement of dura does not imply dural infiltration by tumor. Venous invasion by tumor can be predicted accurately with preoperative MR imaging. 相似文献
770.
WB Weil 《Canadian Metallurgical Quarterly》1996,97(1):129-136
The antibodies to serotonin modulate behavioural reactions of animals depending on the mode of administration (intracerebroventricular or intraperitoneal) and the testing time. Intraventricular injection induces inhibition of behavioural activity within 1--2 hours. Systemic injection produces a biphasic effect on the serotoninergic system, i. e., the activation in the early period and the steady inhibition later. Effects of the intraperitoneally injected serotonin antibodies on the CNS are probably mediated either by serotonin binding in blood or by involvement of neurotrophic factors of the immune system. Both ways of administration of the serotonin antibodies result in late hyperalgesia. 相似文献