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121.
Laryngeal paraganglioma, carcinoid tumor, and small-cell carcinoma are rare. Histologically they are similar to analogous tumors in other locations but may be difficult to identify in small biopsy specimens. We compared the light microscopic, histochemical, immunohistochemical, and electron microscopic features of two laryngeal paragangliomas, one carcinoid tumor, and six small-cell carcinomas. The paraganglioma chief cells stained with Grimelius stain and for chromogranin and neuron-specific enolase. The carcinoid tumor cells stained with Grimelius stain and for chromogranin, serotonin, neuron-specific enolase, and keratin. The small-cell carcinoma cells stained for keratin and neuron-specific enolase. The patients with paragangliomas and carcinoid tumor remain healthy through 20 months of follow-up. Four of the patients with small-cell carcinomas have died. Distinction between these tumors is warranted by differing histologic appearances, staining characteristics, and biologic behavior.  相似文献   
122.
The metabolism of two new 3-methyl-branched iodovinyl fatty acids in rat hearts was evaluated by determining the subcellular and lipid pool distribution of these radiolabeled analogues after intravenous injection. Methyl branching had been introduced into the straight chain analogue, 19-iodo-18-nonadecenoic acid (IVN), to produce the monomethyl analogue, 19-iodo-3-(R,S)-methyl-18-nonadecenoic acid (BMIVN) and the dimethyl derivative, 19-iodo-3,3-dimethyl-18-nonadecenoic acid (DMIVN) in the hope of inhibiting oxidation. Since the presence of 3-methyl branching results in delayed myocardial clearance in rats, differences were sought in the lipid and subcellular distribution of these branched analogues that might correlate with the prolonged retention and reflect differences in metabolism. Hearts of rats injected intravenously with the radiolabeled fatty acids were removed and homogenized and the homogenates partitioned between the chloroform-methanol (organic) fraction and the aqueous fraction. Comparison of the distribution of radioactivity between the organic and aqueous fractions showed that most of the DMIVN and BMIVN activity was in the organic fraction with IVN activity initially divided equally between the two fractions. Identification of the lipid components of these organic fractions showed that there was slow incorporation of DMIVN into the triglyceride and polar lipid fractions with a slow loss from the free fatty acid fraction. With the straight chain IVN analogue which shows rapid washout from rat hearts, there was loss of activity from all 3 lipid components during the 60 min. The monomethyl branched BMIVN analogue demonstrated predominant storage in the polar lipid fraction with some incorporation into triglycerides. Subcellular distribution studies of the three analogues also showed differences that correlated with the observed differences in heart retention properties. With the unbranched IVN analogue, radioactivity was found primarily in the cytoplasmic fraction 30 min after injection, whereas the branched analogues demonstrated a much higher association with the microsomal and mitochondrial fractions of the heart. In rats fed prior to injection, these differences in the subcellular distribution profiles were minimized. The lipid and subcellular distribution patterns reported here for the methyl branched analogues as compared to those of the straight chain iodovinyl fatty acid may provide some understanding as to the mechanisms of retention in rat myocardium.Research supported by the Office of Health and Environmental Research, U.S. Department of Energy, under contract DE-AC0 5-840 R21400 with Martin Marietta Energy Systems, Inc.  相似文献   
123.
High doses of calcitriol were used prospectively for 11 to 29 months to raise serum calcium levels in an effort to control renal osteodystrophy in 16 children undergoing CAPD. Serum Ca, P, iPTH and alkaline phosphatase were measured monthly; hand radiographs were obtained every six months, and a semiquantitative score of bone abnormalities was evaluated by two independent observers. During the study, serum Ca increased from 9.9 +/- 0.9 to 11.0 +/- 0.6 mg/dl (P less than 0.001); serum iPTH decreased by 113 +/- 131 microliter Eq/ml (P less than 0.005); serum P was unchanged; and serum alkaline phosphatase fell by 33 +/- 46% (P less than 0.02), 530 +/- 397 to 204 +/- 551 IU/liter. The radiographic score fell from 4.8 +/- 4.6 to 0.9 +/- 1.2 (P less than 0.005). The average and maximal doses of calcitriol were 0.61 +/- 0.37 and 0.95 +/- 0.56 microgram/day or 28 +/- 18 and 46 +/- 28 ng/kg body wt/day, respectively. Transient and asymptomatic hypercalcemia occurred in nine patients and two patients had reversible conjunctivitis in association with the hypercalcemia. Thus, "high dose" calcitriol prevented or controlled progression of hyperparathyroid bone disease in most pediatric CAPD patients. The failure to suppress PTH or reverse secondary hyperparathyroidism until the serum Ca rose to 10.5 to 11.0 mg/dl could reflect an increase in the "set point" for PTH suppression by serum calcium in many uremic children.  相似文献   
124.
Hemoglobin Setif produces pseudosickling of red cells in vitro; the nature of the process and the conditions that "trigger" it are unknown. Studies of red cells, hemolysates, purified hemoglobin solutions, and artificial mixtures of Hb A and Setif suggest that pseudosickling is produced by intracellular crystallization of insoluble hemoglobin. Increased tonicity of the suspending medium accentuates the process, probably by causing a rise in intracellular hemoglobin concentration. If precipitates from A/Setif mixtures are analyzed, they always contain Hb A, suggesting an unusual mechanism for the process. Despite the fact that osmolality in the renal medulla is similar to that which produces pseudosickling in vitro, carriers do not have renal dysfunction of the type found in patients with sickle cell disease.  相似文献   
125.

Recently 15-p-iodophenyl-β-methyl-pentadecanoic acid (BMPPA) was proposed for use in myocardial scintigraphy, as a possible probe of metabolic processes other than β-oxidation. In 19 patients (CAD/15, St.p. Mi/7; control 4) myocardial scintigraphy was carried out after i.v. I-123-BMPPA (2–4 mCi). Data were collected (LAO 45°/14; anterior/5) for 100 min in the fasted patients. Organ to background (BG) ratios were calculated for the heart (H) and liver (L), and the elimination (E) behaviour was analyzed from BG (vena cava region) corrected time activity curves. In 10 patients plasma and urine were examined. By CHCl3/MeOH extraction of plasma samples (90 min after injection), both in water and in organic medium soluble catabolites were found. TLC fractionation showed that those were co-migrating, compared to standards, with bencoic acid, BMPPA and trigylcerides. In the urine (0–2 h after injection, 4.1% dose) hippuric acid was found. The mean t-max of BMPPA occurred at 15 min in the heart and at 9 min in the liver (P<0.01), with H/BG and L/BG ratios of 1.8 and 2.1, respectively. The elimination of BMPPA was slower from the heart than from the liver (P<0.01). It was biexponential from the liver in all cases (\(\bar x\): t/2 I, 11.4 min; t/2 II, 92 min; t/2 I uncor., 38 min) with the size of phase I smaller than that of phase II (\(\bar x\): I/II, 0.57). From the heart BMPPA turnover was biexponential in 11 patients (\(\bar x\): t/2 I, 13.8 min; t/2 II, 187 min; t/2 I uncor., 65 min; I/II, 0.34), but monoexponential in 8 (\(\bar x\): t/2, 218 min).

In 13 diseased regions (MI/7) BMPPA uptake was reduced, and the E behaviour was mostly abnormal as compared to the respective undiseased region. We conclude that BMPPA is a useful agent for myocardial scintigraphy. Its longer retention time in the heart compared to unbranched radioiodinated fatty acids may facilitate SPECT studies. E behaviour and plasma analysis indicate that BMPPA is metabolically broken down. Yet, the complexity of the supposed mechanism may impede curve interpretation in terms of specific metabolic pathways.

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126.
The differential diagnosis and treatment of pseudodementia, dementia, and depressive illness are receiving increased attention. The literature on this subject is reviewed, and four "ideal types" of patients spanning the spectrum of these illnesses are proposed for use when their distinction or association is at issue. Attempts by investigators to distinguish those groups are summarized, ad the importance of diagnostic clarity and patient selection for future research is emphasized.  相似文献   
127.
Quality of Life Research - Quality of life can be negatively impacted by the formation of a stoma and is influenced by a number of factors. Research to date treats people with a stoma as a...  相似文献   
128.
129.
Background/purposeThough evidence-based clinical pathways for the diagnosis and treatment of pediatric appendicitis have been established, protocols guiding management of percutaneous abscess drains are lacking. We hypothesized a drain management protocol utilizing drain output and clinical factors instead of fluoroscopic drain studies would reduce interventional radiologic procedures without adversely impacting clinical outcomes.MethodsA standardized protocol was uniformly adopted at a tertiary-care children's hospital in April 2016. A retrospective chart review included all cases of appendicitis requiring abscess drainage by interventional radiology three years pre- and postprotocol implementation.ResultsFifty-eight patients (preprotocol = 39, postprotocol = 19) underwent percutaneous abscess drainage, of whom 52 (preprotocol = 34, postprotocol = 18) required a drain. Baseline demographics and clinical presentation were similar across groups. Following protocol implementation, total number of IR procedures decreased from 2.4 to 1.3 per patient (p = 0.004). There was no significant difference in the number of postprocedure diagnostic imaging studies, readmissions, or inpatient days, and there was a trend towards a decrease in number of drain days (10.7 to 5.7, p = 0.067).ConclusionA standardized protocol for management of abscess drains for complicated appendicitis reduced the number of IR procedures without a negative impact on clinical outcomes or increase in alternative imaging studies. This approach may decrease radiation exposure, anesthetic administration, and resource utilization.Type of studyTreatment study (retrospective comparative study).Level of evidenceLevel III.  相似文献   
130.
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