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41.
JE Barberie DG Connell PL Munk DL Janzen 《Journal of Medical Imaging and Radiation Oncology》1999,43(3):355-357
Muscle and nerve injuries in the hand may be difficult to detect and diagnose clinically. Two cases are reported in which magnetic resonance imaging showed ulnar nerve injury and intrinsic hand muscle denervation. The clinical, anatomical and radiological features of injury to the deep motor branch of the ulnar nerve and associated muscle denervation are discussed and illustrated. 相似文献
42.
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy. 相似文献
43.
Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs. 相似文献
44.
Tongue and oropharynx: findings on MR imaging 总被引:6,自引:0,他引:6
Lufkin RB; Wortham DG; Dietrich RB; Hoover LA; Larsson SG; Kangarloo H; Hanafee WN 《Radiology》1986,161(1):69-75
Ten healthy subjects and 44 patients with diseases of the tongue or oropharynx were studied with magnetic resonance (MR) imaging. Axial, coronal, and sagittal images with a thickness of 4 mm were obtained with a pixel size of 0.75 X 0.75 mm on a 256 matrix. Nineteen of the patients underwent computed tomography (CT). Nine of those patients later had surgery, and the specimens were obtained for organ sectioning. These three studies as well as clinical history and physical examination findings were correlated. MR imaging was equal to or better than CT in those patients having both examinations. However, neither CT nor MR allowed recognition of histologic features or detection of microscopic spread of disease. Direct coronal and sagittal imaging planes on MR imaging allowed visualization of intrinsic tongue musculature, not possible with CT; this was important in recognizing subtle tumor extension. For these reasons, MR is the imaging method of choice for studying diseases of the tongue and oropharynx. 相似文献
45.
We reviewed data from the Vessel Sanitation Program (VSP), established by the US Public Health Service in 1975, to describe the epidemiology of shipboard diarrhoeal outbreaks, determine the risk of outbreak-related illness among cruise ship passengers, and evaluate changes in rates and patterns of shipboard diarrhoeal illness since the VSP was implemented. When the programme began, none of the cruise ships passed periodic VSP sanitation inspections; since 1978, more than 50% of ships have met the standard each year. On cruises lasting 3-15 days and having at least 100 passengers, diarrhoeal disease outbreaks investigated by the Centers for Disease Control decreased from 8.1 to 3.0 per 10 million passenger days between 1975-79 and 1980-85. The proportion of outbreaks due to bacterial pathogens (36%) did not change. Seafood cocktail was implicated in 8 of 13 documented food-borne outbreaks. The risk of diarrhoeal disease outbreaks on cruise ships appears to have decreased since implementation of the VSP but has not been eliminated. 相似文献
46.
47.
A human monocyte-like cell line, U937, when grown in continuous culture, does not secrete lysosomal enzymes or migrate towards chemotactic factors. When the cells are stimulated by lymphokines, however, they develop the ability both to migrate directionally and to secrete enzymes in response to several types of chemoattractants. The development, by stimulated cells, of chemotactic and secretory responses to one class of chemoattractants, the N- formylated peptides, is accompanied by the appearance on the cells of specific binding sites for these substances. Using tritiated N-formyl- methionyl-leueyl-phenylalanine (fMet-Leu-[(3)H]Phe) as a ligand, it was determined that unstimulated U937 cells possess no detectable binding sites. However, after stimulation with lymphocyte culture supernates for 24, 48, and 72 h, they developed 4,505 (+/-) 1,138, 22,150(+/-) 4,030, and 37,200 (+/-) 8,000 sites/cell, respectively. The dissociation constants for the interaction of fMet-Leu-[SH]Phe with the binding sites were approximately the same regardless of stimulation time and ranged between 15 and 30 nM. The binding of fMet-Leu-[(3)H]Phe by stimulated U937 cells was rapid and readily reversed by the addition of a large excess of unlabeled peptide. The affinity of a series of N-formylated peptides for binding to U937 cells exactly reflected the potency of the peptides in inducing lysosomal enzyme secretion and chemotaxis. The availability of a continuous human monocytic cell line that can be induced to express receptors for N-formylated peptides will provide a useful tool not only for the characterization of such receptors but also for the delineation of regulatory mechanisms involved in cellular differentiation and the chemotactic response. 相似文献
48.
Plasma homocysteine, a risk factor for cardiovascular disease, is lowered by physiological doses of folic acid 总被引:9,自引:0,他引:9
Ward M; McNulty H; McPartlin J; Strain JJ; Weir DG; Scott JM 《QJM : monthly journal of the Association of Physicians》1997,90(8):519-524
Elevated plasma homocysteine, an independent risk factor for cardiovascular
disease (CVD) can be lowered by administration of pharmacological doses of
folic acid. The effect of lower doses in apparently normal subjects is
currently unknown but is highly relevant to the question of food
fortification. Healthy male volunteers (n = 30) participated in a chronic
intervention study (26 weeks). Folic acid supplements were administered
daily at doses increasing from 100 micrograms (6 weeks), to 200 micrograms
(6 weeks), to 400 micrograms (14 weeks). Fasting blood samples collected
before, during and 10 weeks post intervention were analysed for plasma
homocysteine, serum and red- cell folate levels. Results, expressed as
tertiles of baseline plasma homocysteine concentration, showed significant
(p < or = 0.001) homocysteine lowering in the top (10.90 +/- 0.83
mumol/l) and middle (9.11 +/- 0.49 mumol/l) tertiles only. In the low
tertile, where the mean baseline homocysteine level was 7.07 +/- 0.84
mumol/l, no significant response was observed. Of the three folic acid
doses, 200 micrograms appeared to be as effective as 400 micrograms, while
100 micrograms was clearly not optimal. There is thus a minimal level of
plasma homocysteine below which folic acid has no further lowering effect,
probably because an optimal folate status has been reached. A dose as low
as 200 micrograms/day of folic acid is effective in lowering plasma
homocysteine concentrations in apparently normal subjects. Any public
health programme for lowering homocysteine levels, with the goal of
diminishing CVD risk, should not be based on unnecessarily high doses of
folic acid.
相似文献
49.
50.
We report a patient with a clinical and molecular diagnosis of LEOPARD syndrome (LS) associated with multiple granular cell tumors (MGCT). Bidirectional sequencing of exons 7, 12, and 13 of the PTPN11 gene revealed the T468M missense mutation in exon 12. This mutation has been previously reported in patients with LS. To our knowledge, this is the first report of MGCT associated with molecularly characterized LS and provides the first molecular evidence linking granular cell tumors (GCT) to the Ras/mitogen-activated protein (MAP) kinase pathway. We propose that MGCT can be associated with LS. Analysis of GCT from this case tested negatively for loss of heterozygosity (LOH) at the PTPN11 and NF1 loci and did not show deletions of the PTEN gene. The absence of LOH of PTPN11 supports published functional data that T468M is a dominant-negative mutation. 相似文献