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41.
We studied the response of 14 normal volunteers and five septic patients to a 48-hour course of exogenous biosynthetic human growth hormone (hGH) or placebo. Six normal controls (group 1) received saline, eight normal controls received hGH (group 2), and five septic patients also received biosynthetic hGH (group 3). Urinary urea excretion declined, and splanchnic amino acid uptake was maintained only in group 2 subjects. Septic patients exhibited changes in amino acid and urea dynamics comparable to those of subjects receiving placebo. Insulinlike growth factor 1 (IGF-1) production and plasma concentrations increased in group 2 in a fashion corresponding to the changes in nitrogen exchange, whereas septic patients exhibited no change in IGF-1 level. Therefore, in this septic patient group, exogenous hGH was ineffective in attenuating nitrogen losses and stimulating IGF-1 production. This supports the hypothesis that IGF-1 is a mediator of the anabolic effect of hGH. 相似文献
42.
The main purpose of this communication is to alert nuclear medicine departments to the fact that the earlier version of the water phantom grossly overestimates soft-tissue attenuation in the neck, resulting in calculated thyroid uptake values which are significantly overestimated (in hyperthyroid patients we noted uptake values approaching or exceeding 100%). We believe that the solid Lucite phantom (which is the one recommended by IAEA) better approximates the human neck soft tissue overlying the thyroid. Institutions that continue to use the water phantom should be aware that their thyroid uptakes will be relatively elevated and the normal range must be shifted accordingly. Our normal range is 10%-30% uptake of 123I at 24 hr for the Lucite phantom. For the water phantom, the estimated normal range would be 15%-45%. In addition, the phantom type should be considered when comparing uptake results with those from another institution for a particular patient. Also, treatment doses for Grave's disease could be significantly affected, if such doses are calculated by a formula that depends on uptake. 相似文献
43.
Hubert A. Shaffer Jr. M.D. Donald A. Eckard Eduard E. de Lange M. R. Ramakrishnan 《Abdominal imaging》1988,13(1):221-223
Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart. 相似文献
44.
Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
45.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
46.
Mobilization and evolutionary history of miniature inverted-repeat transposable elements (MITEs) in Beta vulgaris L. 总被引:1,自引:0,他引:1
Gerhard Menzel Daryna Dechyeva Heiko Keller Cornelia Lange Heinz Himmelbauer Thomas Schmidt 《Chromosome research》2006,14(8):831-844
We have identified three families of miniature inverted-repeat transposable elements (VulMITEs) in the genome of sugar beet
(Beta vulgaris L.), evidently derived from a member of the Vulmar family of mariner transposons. While VulMITEs I are typical stowaway-like MITEs, VulMITEs II and VulMITEs III are rearranged stowaway elements of increased size. The integration of divergent moderately and highly repetitive sequences into VulMITEs II and,
in particular in VulMITEs III, respectively, shows that amplification of repetitive DNA by MITEs contribute to the increase
of genome size with possible implications for plant genome evolution. Fluorescent in-situ hybridization (FISH), for the first time visualizing stowaway MITE distribution on plant chromosomes, revealed a dispersed localization of VulMITEs along all B. vulgaris chromosomes. Analysis of the flanking sequences identified a dispersed repeat as target site for the integration of the stowaway element VulMITE I. Recent transposition of VulMITE I, which most likely occurred during the domestication of cultivated beets, was concluded from insertional polymorphisms between
different B. vulgaris cultivars and species.
†Sequence data from this article have been deposited in the EMBL/GenBank Data Library under the accession nos. AM231630-AM231653
and AM259123-AM259125. 相似文献
47.
J. Labadie M. J. D. van Tol N. H. Dijkstra M. van der Kaaden C. M. Jol van der Zijde G. G. de Lange F. E. Zwaan J. M. Vossen 《British journal of haematology》1992,82(2):437-444
A rapid recovery of specific humoral immunity in the recipient of an allogeneic bone marrow transplantation (BMT) can be observed after immunization of the donor before graft sampling. This has been attributed to transfer of specific immunity from donor to recipient. However, to maintain the concept of transfer the origin of the antibody producing cells in the recipient after BMT must be demonstrated. To this end, donor-recipient pairs with differences in Gm-allotypes were selected and immunized before BMT with the neo-antigen Helix pomatia haemocyanin (HPH) according to three immunization protocols. Additionally, the recipients were immunized at day 42 after BMT. Serum samples were weekly obtained from the recipients in the first 100 d after BMT. The origin of HPH-specific antibody producing cells was assessed by two approaches: (1) determination of the Gm-allotypes of anti-HPH antibodies within a distinct IgG subclass, (2) analysis of anti-HPH antibody spectrotypes by isoelectric focusing combined with immunoblotting. The results obtained with these two approaches show concordance in most instances and led to the conclusion that the antibody producing cells are of donor origin. 相似文献
48.
49.
A randomized, prospective trial of postoperative somatostatin analogue in patients with neuroendocrine tumors of the pancreas. 总被引:4,自引:0,他引:4
J R Lange S M Steinberg G M Doherty H N Langstein D E White T H Shawker R C Eastman R T Jensen J A Norton 《Surgery》1992,112(6):1033-7; discussion 1037-8
BACKGROUND. Pancreatic surgery is not uncommonly complicated by prolonged pancreatic drainage and fistula. Octreotide decreases pancreatic exocrine function and has been reported to improve closure of pancreatic and intestinal fistulae. This randomized, prospective trial was designed to evaluate the efficacy of postoperative octreotide in reducing pancreatic drainage and complications after resection of neuroendocrine tumors of the pancreas. METHODS. Patients with neuroendocrine tumors of the pancreas were entered into the study and randomized after operation to receive octreotide 150 micrograms subcutaneously every 8 hours or saline solution subcutaneously every 8 hours in a double-blinded fashion. Daily pancreatic drainage, total drainage, number of days to drain removal, and complications were recorded. RESULTS. Ten patients were given octreotide; eleven patients were given saline solution. The number of days to drain removal, daily drainage, and total drainage were not significantly different. Complications related to pancreatic drainage were not significantly different. CONCLUSIONS. Octreotide is not indicated for the routine postoperative management of patients with neuroendocrine tumors of the pancreas. 相似文献
50.
Harry Pantazopoulos Nicholas Lange Ross J Baldessarini Sabina Berretta 《Neuropsychopharmacology》2007,61(5):640-652
BACKGROUND: Growing evidence indicates that the entorhinal cortex (ECx) might be affected in schizophrenia (SZ) and bipolar disorder (BD). To test whether distinct interneuronal subpopulations might be altered, numbers of parvalbumin-immunoreactive (PVB-IR) neurons were measured in the ECx of BD and SZ subjects. These neurons play a pivotal role within ECx intrinsic circuits. METHODS: Numbers, numerical density, and soma size of PVB-IR neurons were measured in the ECx of normal control (n = 16), BD (n = 10), and SZ (n = 10) subjects. The volume of the ECx was measured in Nissl-stained sections. RESULTS: In BD, decreases of total numbers (p = .02) and numerical densities (p = .01) of PVB-IR neurons were detected in the ECx. Within distinct subregions, reductions were detected in the superficial layers of the lateral (p = .02), intermediate (p = .04), and caudal (p = .01) ECx. In SZ, total numbers and numerical densities were not altered. A reduction of soma size was present in the intermediate ECx (p = .01). Volume was unaffected in either disorder. CONCLUSIONS: In BD, a decrease of PVB-IR neurons may alter intrinsic inhibitory networks within the superficial layers of the ECx. The likely consequence is a disruption of integration and transfer of information from the cerebral cortex to the hippocampus. 相似文献