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61.
Twenty-four hour urine specimens from 5,677 stone-forming patients throughout the United States were analyzed for seasonal variations in urinary risk factors for nephrolithiasis. Determinations were performed for urine volume, pH, calcium, oxalate, phosphorus, sodium, magnesium, citrate, sulfate, uric acid, and the relative supersaturation (RS) of calcium oxalate, brushite, monosodium urate, and uric acid. Criteria for significant seasonal variation included a significant difference in monthly means of risk factors, seasonal grouping of the data by the Student-Newman-Keuls multiple range test, consistent year-to-year trends and a physiologically significant range. Minimum urine volume of 1.54 +/- 0.70 SD L/day occurred in October while a maximum urine volume of 1.76 +/- 0.78 SD L/day was observed during February. Minimum urine pH of 5.94 +/- 0.64 SD was observed during July and August while a maximum pH of 6.18 +/- 0.61 SD was observed during February. Daily urinary excretion of sodium was lowest during August, 158 +/- 74 SD mEq/day and highest during February 177 +/- 70 SD mEq/day. The RS of brushite and uric acid were found to display significant pH-dependent seasonal variation with a maximum RS of uric acid 2.26 +/- 1.98 SD in June and a low of 1.48 +/- 1.30 SD in February. Maximum RS of brushite 2.75 +/- 2.58 was observed during February. Minimum RS of brushite 1.93 +/- 1.70 SD was observed in June. Phosphorus excretion displayed seasonal variation about a spring-fall axis with a maximum value 1042 +/- 373 SD mg/day in April and a minimum value of 895 +/- 289 SD mg/day. Urine volume, sodium, and pH were significantly lower during the summer (June, July, August) than in the winter (December, January, February). The RS of uric acid was higher, but that of brushite and monosodium urate was lower in the summer than in the winter. The seasonal changes observed in urine volume, pH, sodium, and the RS of brushite and uric acid are consistent with summertime sweating and increased physical activity. Seasonal variations in phosphorus excretion are probably dietary in origin. The summertime was characterized by an increased propensity for the crystallization of uric acid but not of calcium oxalate or calcium phosphate.  相似文献   
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RO Briere 《Transfusion》1988,28(4):392-393
Alanine aminotransferase (ALT) measurements in blood donors has been advocated as a surrogate test for non-A, non-B hepatitis. Use of the recommended single cutoff value for all donors resulted in disqualifying four times as many males as females in a group of 4712 donors. Separate cutoff values were calculated for male and female donors. The use of these separate cutoff values resulted in disqualifying equal numbers of males and females.  相似文献   
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Gondak R O, Alves D B, Silva L F F, Mauad T & Vargas P A
(2012) Histopathology  60, 497–503
Depletion of Langerhans cells in the tongue from patients with advanced‐stage acquired immune deficiency syndrome: relation to opportunistic infections Aims: To quantify and compare the expression of Langerhans cells (LCs) in the tongue mucosa of AIDS patients with different opportunistic infections, and from acquired immune deficiency syndrome (AIDS) and non‐AIDS patients with normal tongues, using autopsy material. Methods and results: Human leucocyte antigen D‐related (HLA‐DR), CD1a and CD83 antibodies were used to identify and quantify LCs by immunohistochemistry in tongue tissue of 40 AIDS patients (10 with lingual candidiasis, 10 with lingual herpes, 10 with oral hairy leukoplakia and 10 with no lesions) and 23 tongues from human immunodeficiency virus (HIV)‐negative control patients. Quantification was performed by means of conventional morphometry in four different regions (anterior, middle, posterior and lateral) of the tongue. The results were expressed as positive cells per area of epithelium. The AIDS patients presented a lower density of CD1a+ cells (P < 0.001), HLA‐DR (P < 0.003) and CD83 (P < 0.001) in all regions of the tongue compared to the non‐AIDS control group. However, no differences in any of the markers were found when AIDS patients with different opportunistic infections were compared with AIDS patients without tongue infection. Conclusions: Advanced stage AIDS patients showed a depletion of LCs in the tongue mucosa. HIV infection induces cytopathic changes in LCs, contributing to their depletion regardless of the presence of oral infections.  相似文献   
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Summary. Background: This study aimed to evaluate untreated, previous pulmonary thromboembolism (PE) in patients with acute fatal PE. Patients and Methods: We studied 64 patients diagnosed as having died from acute PE by medico‐legal autopsy. Previous PE was histologically confirmed on the basis of organized thrombi (OT). The distributions of OT were analyzed in five different sizes of pulmonary artery branches in each of 18 pulmonary segmental arteries (90 in total). The frequency of OT in each patient was evaluated by determining the percentage of examined sections containing OT. Results: OT were confirmed in 59 of 64 (92%) patients. The mean frequency of OT per patient was 27% of the 90 branches. Among the segmental arteries, the right posterior basal lobe showed the highest frequency of OT; among the five artery branches examined, the subsegmental branch showed the highest frequency of OT. OT were not detected in arterioles. Patients with recent trauma or surgery and inpatients showed significantly lower frequencies of OT than those without these risk factors. The 26 patients with prolonged pre‐existing symptoms lasting more than a day showed a higher frequency of OT than the 12 patients who suffered for less than a day and the 26 without pre‐existing symptoms. Conclusions: Most patients with acute fatal PE have a subclinical history of recurrent PE. The frequency of their untreated PE is suspected to correlate with specific risk factors for venous thromboembolism and their clinical course.  相似文献   
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Clinical Oral Investigations - To compare the proportion of young (up to 45&nbsp;years of age) and older (over 45&nbsp;years of age) oral squamous cell carcinoma (OSCC) patients who report...  相似文献   
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