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1.
The effects of nonprotein energy source (ie, glucose only vs glucose and lipid) on nitrogen retention and total-body protein turnover were studied in 20 parenterally fed newborn infants. All infants received approximately 3 g amino acids and 80-90 kcal.kg body wt.d. Total-body protein synthesis was estimated by using three constant-infusion, end-product methods: enrichment of urinary urea and ammonia in response to a [15N]glycine label and exhaled carbon dioxide enrichment in response to a [1-13C]leucine label. No differences were seen in nitrogen retention between the two energy sources. The estimate of total-body protein turnover obtained from the 13C label was similar to that obtained with the [15N]urea label. No differences in turnover rates were observed between the two diet groups. Use of the glucose-plus-lipid fuel system enhanced energy storage and the reutilization of amino acid for protein synthesis.  相似文献   
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Eleven patients with refractory rheumatoid arthritis were submitted to a total lymphoid irradiation up to a dose of 20 Gy. A constant improvement of clinical symptoms was observed in four out of the eleven patients already during the treatment and in the other patients not later than two months after. The frequency of attacks decreased and the number of joints involved in the attack was reduced. Morning rigidity and joint swellings decreased. One patient developed joint empyemas 4 and 26 months after the treatment. Four patients died in the meantime. In two patients the cause of death were renal insufficiency and a postoperative cardiogenic shock associated with generalized amyloidosis. The third patient died because of a toxically induced left cardiac decompensation with sepsis that could not be controlled by antibiotic drugs and multiple joint empyemas. The fourth patient developed an abscess after surgical treatment of a Kaposi syndrome. She died three months later from acute left cardiac decompensation. The therapy induced a lymphocytopenia with decrease of T helper lymphocytes and unchanged number of T suppressor lymphocytes. The constant therapy results of total lymphoid irradiation in primary chronic polyarthritis is probably due to this modification in the immune regulation.  相似文献   
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The treatment results obtained in patients with both small and non small cell lung cancer have remained stagnant for years. Therefore, in order to select patients who will have a profit from radiotherapy the indication has to take into account prognostic factors such as tumor stage, extent of resection, patient's age, lymph node status, weight loss and the patient's performance status. Non small cell lung cancer: Postoperative radiotherapy seems to benefit only in patients with hilar or mediastinal lymph node involvement, where a five-year survival rate of up to 30% of cases can be achieved. Postoperative irradiation should not be applied following curative resection and negative lymph node status (R0 N0). In inoperable cases conventional fractionated radiotherapy may definitively have a favourable effect on the patient's survival time, even when the treatment was originally intended to be merely palliative. Only those patients will live five years, who received more than 50 Gy to the hilar and mediastinal nodes and at least 60 Gy to the primary lesion. The volume to be irradiated must include the primary tumor, the ipsilateral and contralateral hilum, the mediastinum, and both supraclavicular regions. If a Pancoast tumor is present, radiotherapy alone obtains a similar result as preoperative irradiation followed by resection. Small cell lung cancer: Radiation treatment of the primary tumor region and the lymph drainage area increases the remission rate by roughly 20% compared with chemotherapy alone, considerably reduces the incidence of local recurrences and exerts a beneficial effect on the survival of the patients. Recently, this has been confirmed by prospectively randomised protocols. Prophylactic brain irradiation has been found to decrease the risk of cerebral metastases to 4-6% in patients affected by limited disease and complete tumor remission under chemotherapy, and to improve the quality of life without, however, showing the benefit on survival time. Future efforts in radiotherapy should be aimed not only at increasing dose intensities but also at developing less toxic treatment modalities to the benefit of the quality of life.  相似文献   
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The present study was conducted on 33 children (median age at initial cardiac catheterization 0.4 years [0.1 to 11.8]) with anomalous origin of the left coronary artery from the pulmonary artery, without associated hemodynamically significant cardiovascular anomalies, who were treated throughout a period of 18 years in our hospital. A two coronary artery circulation was reestablished in 31 of 33 children. One child died before the intended operation, and in one child the left coronary artery was ligated. There were six operative deaths, five intraoperative and one 12 hours after operation. The purpose of the study was to assess which preoperative clinical and angiographic features were associated with a higher perioperative mortality. The following preoperative factors were associated with a statistically significant higher perioperative mortality: young age at operation (p less than 0.03), left and balanced type of coronary circulation (p less than 0.01), and electrocardiographic signs of extensive acute myocardial infarction, namely, marked ST elevation (greater than or equal to 0.2 mV in at least two leads) (p less than 0.03). Left axis deviation on the electrocardiogram was associated with an extreme right dominant type of coronary circulation (p less than 0.005). The latter was also linked with adequate perfusion of the posterolateral left ventricular wall (p less than 0.005). At autopsy, severe increase of heart weight to two or three times the normal heart weight was established in six of seven children. Thus the perioperative mortality was determined primarily by the extent of myocardial ischemia. This in turn is decisively influenced by the dominant type of coronary circulation and the extent of inter-arterial collateralization. Young age, in addition, proved to be a risk factor for mortality at corrective surgery.  相似文献   
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STUDY OBJECTIVE: To assess the clinical utility of measuring urinary pregnanediol glucuronide in random samples in an infertility practice. DESIGN: Samples of urine were collected from patients approximately 3 weeks from their last menstrual period to ascertain if ovulation had occurred. Each sample was tested for specific gravity before analyzing for pregnanediol glucuronide. Simultaneous venipuncture was performed to compare results from the urinary assay to quantitative measures of serum progesterone (P). SETTING: All patients were randomly sampled. PATIENTS: Three hundred ninety women undergoing pituitary down regulation with leuprolide acetate were chosen for study because they routinely initiate medication after documentation of ovulation. OUTCOME MEASURES: The performance of the urinary pregnanediol glucuronide was evaluated as to its sensitivity, specificity, predictive value, and test efficiency compared with a serum measurement of 2.5 ng/mL and 10.0 ng/mL. RESULTS: The performance characteristics of the pregnanediol glucuronide assay were directly related to the hydration status of the patient at the time of sample collection. Regardless of urine specific gravity, if pregnanediol glucuronide was qualitatively detected (greater than 3 micrograms/mL), serum P was greater than 2.5 ng/mL. However, in cases in which pregnanediol glucuronide was undetected (less than 3 micrograms/mL), results were only accurate when the specific gravity was greater than or equal to 1.020. When comparing urinary pregnanediol glucuronide values to serum greater than 10 ng/mL, both specificity and predictive value of a positive test decreased because of increased numbers of false-positive results. CONCLUSIONS: The enzyme immunoassay measurement for pregnanediol glucuronide may replace the use of serum P in documenting the ovulatory status of many patients. However, all specimens must be checked for specific gravity and if less than 1.020, a serum P should be used to ensure accuracy.  相似文献   
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Chronic low back pain: comparison of bone SPECT with radiography and CT   总被引:1,自引:0,他引:1  
Ryan  PJ; Evans  PA; Gibson  T; Fogelman  I 《Radiology》1992,182(3):849
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Excitotoxic neurodegeneration in the rat striatum was induced by direct injection of quinolinic acid. The degree of damage was evaluated in vivo 1 day later by quantitative magnetic resonance imaging (MRI) and 7 days later in the same animals by measuring the activities of the neuronal marker enzymes choline acetyltransferase and glutamic acid decarboxylase. Striatal damage assessed using the two approaches was highly correlated. Moreover the cerebroprotective efficacy of the N-methyl-D-aspartate receptor antagonist CGP 40116 was indistinguishable based on all analytical parameters. MRI, however, was more reproducible than the enzymatic methods and was faster and simpler for routine analyses of excitotoxic damage and cerebroprotection in vivo.  相似文献   
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