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41.
42.
Bilirubin interferes with the measurement of plasma creatinine by the kinetic colorimetric Jaffe reaction, the method currently used by many hospital laboratories. The purpose of the present study was to evaluate the influence of unconjugated bilirubin on the measurement of plasma creatinine by the AutoAnalyzer Jaffe end point method. This colorimetric method is slower but more precise and accurate in the range of 0.25 to 0.5 mg/dl. We found that bilirubin from jaundiced neonates and from stock solutions did not affect the determination of creatinine chromogen in plasma or in saline, even at concentrations as high as 25 mg/dl. We conclude that the use of the Jaffe end point AutoAnalyzer method with a blank run before each sample will provide an accurate measurement of creatinine in the plasma of the neonate with unconjugated hyperbilirubinemia.  相似文献   
43.
An estimate of glomerular filtration rate has been derived for children from body length (L, in centimeters) and plasma creatinine (Pcr, in milligrams per deciliter): GFR = 0.55 L/Pcr. The near universality of this estimate in children led us to seek a similar formula for estimating GFR in full-term infants during the first year of life. We measured Pcr in 137 healthy infants and performed creatinine clearance (Ccr) studies in 63 of them aged greater than or equal to 5 days. Beyond the first week, Pcr averaged 0.39 +/- 0.01 (0.10 SD) mg/dl. The estimate of GFR from 0.55 L/Pcr overestimated Ccr by 24% (P less than 0.001). Based on the calculation of a new constant from Ccr X Pcr/L, GFR was more accurately estimated from 0.45 L/Pcr (mean difference of Ccr - 0.45 L/Pcr = -0.4 +/- 3.7 (SE) ml/min X 1.73 m2) in full-term infants between 1 and 52 weeks of age. Because the constant 0.45 and Pcr do not change significantly during this period, GFR can be approximated at the bedside from body length of the healthy full-term infant (GFR = 0.45 L/0.39 = 1.1 L).  相似文献   
44.
Most patients with colorectal cancer (CRC) who have failed initial 5-fluorouracil (5-FU) chemotherapy have worsening of disease-related symptoms (DRS) and quality of life (QOL). Irinotecan has a reported response rate of 10%-20% in such patients. The aim of this phase II trial was to prospectively determine the palliative benefit of irinotecan utilizing DRS as primary endpoints of response. Patients had advanced CRC refractory to 5-FU with at least 1 DRS defined as (1) Karnofsky performance status (KPS) 60%-80%, (2) baseline analgesic use > or = 10 mg morphine/day (or equivalent), or (3) disease-related pain score > 1 cm on a 10-cm linear analogue self-assessment (LASA) scale. Patients received irinotecan 125 mg/m2 weekly for 4 weeks on an every-6-weeks schedule. The primary endpoint was palliative response defined as > or = 50% decrease in pain score or analgesic usage, or 10% increase in KPS, from baseline for 4 weeks. QOL was assessed by the European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire Core 30 (EORTC QLQ-C30) version 2 instrument. A total of 65 patients were entered onto the study. Median baseline parameters were KPS 70%, analgesic score 11 mg/day, and pain score 2.4 cm. A palliative response was achieved in 27 patients (42%), improvement in pain score predominated. LASA and EORTC QLQ-C30 instruments showed parallel changes in DRS. The radiological response rate was 11% (complete responses and partial responses, n = 46); 23 patients achieved stable disease. Median overall survival was 7.2 months. Irinotecan provides a rate of palliative benefit higher than the radiological response rate. Patients-oriented palliative endpoints can be useful in assessing the benefit of agents in early-phase clinical trials.  相似文献   
45.
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.  相似文献   
46.
Although fine-needle aspiration biopsy of salivary gland masses has been reported in the otolaryngology literature, the use of sonography to guide the biopsy of nonpalpable masses and masses seen on other cross-sectional imaging studies has not been described. Our goal was to evaluate sonographically guided biopsy of masses and lymph nodes related to the salivary glands. We analyzed the records of 18 patients who had undergone fine-needle aspiration biopsy of a salivary gland mass or lymph node with a 25-, 22-, or 20-gauge needle. A definitive cytologic diagnosis was made for 13 of the 18 patients (72%); cytology was suggestive but not definitive in three patients (17%) and insufficient in two (11%). Definitive diagnoses were made in three cases of reactive lymph node, in two cases each of lymph node metastasis and Warthin's tumor, and in one case each of pleomorphic adenoma, adenoid-cystic carcinoma, schwannoma-neurofibroma, parotid metastasis, parotid lymphoma, and Sj?gren's-related lymphoid-epithelial lesion. Sonographically guided biopsy allows for confident needle placement in masses seen on computed tomography and magnetic resonance imaging. Sonography can usually distinguish a perisalivary lymph node from true intrasalivary masses, and it can help the surgeon avoid the pitfall of a nondiagnostic aspiration of the cystic component of masses. We conclude that sonographically guided biopsy of salivary gland masses can provide a tissue diagnosis that can have a direct impact on clinical decision making.  相似文献   
47.
Markowitz  RI 《Radiology》1988,167(3):717-719
The anterior junction line is a normal anatomic landmark on chest radiographs of healthy adults and older children caused by the visceral and parietal pleurae of the two lungs meeting anteriorly at the midline. It is not seen on chest radiographs of healthy infants. When this sign is identified on the supine frontal view of a neonate, it signifies bilateral pneumothorax. In this situation the line is formed by the meeting of the medial parietal pleurae on each side as they herniate anteriorly in front of the thymus and heart. The sign is best seen when the patient is rotated slightly to the left. It is not seen when there is unilateral pneumothorax or a concomitant pneumomediastinum. Although the anterior junction line is not a highly sensitive indicator of bilateral pneumothorax, it is highly specific and its recognition can promote faster diagnosis.  相似文献   
48.
An 18-year-old renal transplant patient presented with sudden onset of seizures almost 2 years after she received the graft. Diagnostic work-up was unrevealing except for magnetic resonance imaging abnormalities of the brain that resolved spontaneously 4 weeks later. In this brief report, we discuss the etiology of the seizures and neurological abnormalities in renal transplant patients in light of the findings of our patient. Received September 15, 1995; received in revised form and accepted March 20, 1996  相似文献   
49.
50.
The frequency of lung cancer, common in both men and women, seems to be increasing rapidly, particularly in women. The main causative factor appears to be cigarette smoking. Diagnosis and staging have not changed notably in the last few years, although the advent of computerized tomography and gallium scanning have been of some help in identifying mediastinal tumours, which are unresectable. Further refinements in these techniques may allow us to avoid mediastinoscopy but, at present, this is still usually necessary before operation for lung cancer. Operation is the major form of therapy for non-small cell cancer when this is medically and technically possible. Adjuvant therapy in the treatment of this type of lung cancer has so far been of little help. Radiotherapy as primary treatment, although occasionally curative, should be used only if patients refuse operation or clearly have medical contraindications for thoracotomy. Radiotherapy is very useful for palliation. Chemotherapy is of little value in treating advanced, non-small cell lung cancer, although responses can be seen in up to 40% of patients. This does not translate into important, long-term survival, but responders do survive longer than non-responders. Patients with small cell lung cancer should be treated with combination chemotherapy, with or without thoracic irradiation and with or without cranial irradiation. The latter two modalities have not yet been proved to prolong survival, but may reduce the morbidity. Immunotherapy has not been shown to benefit those with non-small cell lung cancer. Thymosin was beneficial in one controlled trial in patients with small cell lung cancer, but this must be confirmed. In the future, many new approaches will be necessary to control or eradicate this steadily increasing cause of cancer death.  相似文献   
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