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71.
We report a patient with metastatic thyroid carcinoma invading the esophagus in whom barium and MR examinations revealed an expansile intraluminal mass indistinguishable from that of a primary esophageal malignancy. Metastatic thyroid carcinoma should therefore be included in the differential diagnosis of an expansile esophageal mass. As in our patient, MR imaging may be useful for showing that the mass originates in the thyroid gland. 相似文献
72.
Fatality resulting from methylphenidate overdose 总被引:1,自引:0,他引:1
A case involving an accidental overdose fatality resulting from an intravenous injection of crushed Ritalin (methylphenidate) tablets is presented. The drug was quantified by gas chromatography/nitrogen-phosphorus detection and confirmed by gas chromatography/mass spectrometry. Concentrations of drug were as follows: blood, 2.8 mg/L; bile, 5.7 mg/L; kidney, 3.0 mg/kg; liver, 2.1 mg/kg; and stomach contents, 1.6 mg total. Other drugs and volatile substances were not detected. 相似文献
73.
Joseph Levine Mirtha Gonsalves Izak Babur Shaul Stier Avner Elizur Ora Kofman R. H. Belmaker 《Human psychopharmacology》1993,8(1):49-53
Inositol is an important precursor for second messenger synthesis and has been reported to be reduced by lithium treatment in rat brain and in human CSF in depression. An open trial of 6 g/day in 11 depressed patients resistant to previous treatment led to major improvement in nine patients. The enzyme synthesizing inositol has been reported to be elevated in schizophrenia, suggesting an attempted compensation for possible inositol deficiency. A controlled double-blind crossover trial in 10 chronic schizophrenic patients of 6 g/day of inositol for 30 days did not reveal any benefit. 相似文献
74.
Safety and immunogenicity of Salmonella typhi Ty21a vaccine in young Thai children. 总被引:5,自引:3,他引:2
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S J Cryz Jr N Vanprapar U Thisyakorn T Olanratmanee G Losonsky M M Levine S Chearskul 《Infection and immunity》1993,61(3):1149-1151
Salmonella typhi Ty21a vaccine in a liquid formulation was evaluated in 634 Thai children 2 to 6 years of age. The seroconversion rate was 69% for those who received vaccine versus 14% for those who received placebo (P < 0.005). The immune responses among vaccine recipients ranged from 60% in 3-year-olds to 81% for 6-year-olds. 相似文献
75.
76.
77.
Spindle-cell adenomyoepithelioma of the breast. A microscopic, ultrastructural, and immunocytochemical study 总被引:1,自引:0,他引:1
Two patients developed nodular, well-circumscribed tumors of the breast, discovered by mammography. They were fibroadenoma-like by gross examination and biphasic by light microscopy, containing both tubular glands and spindled myoid cells. Immunocytochemical studies revealed cytokeratin and S-100 immunoreactivity in both the spindled myoid cells and in the tubuloglandular cells (S-100 was focal in the latter). In addition, the spindled myoid cells were immunoreactive for vimentin but negative for desmin. Ultrastructural studies showed the tubular glands to be composed of luminal epithelial cells focally surrounded by myoepithelial cells, but the stroma contained spindled myoepithelial cells admixed with occasional fibroblasts. The diagnostic term, "adenomyoepithelioma," is appropriate for biphasic tumors having both glandular and myoepitheliomatous differentiation. Although additional experience is necessary to be conclusive regarding the biologic behavior of these unusual lesions, the authors believe the adenomyoepitheliomas described here are benign. They were well circumscribed without invasion of adjacent breast, contained neither mitotic figures nor cytologic atypia, and have not recurred or metastasized (6 and 10 months after removal). 相似文献
78.
Pressure recovery distal to a stenosis: potential cause of gradient "overestimation" by Doppler echocardiography 总被引:1,自引:0,他引:1
R A Levine A Jimoh E G Cape S McMillan A P Yoganathan A E Weyman 《Journal of the American College of Cardiology》1989,13(3):706-715
Doppler ultrasound is currently being widely applied to measure intracardiac pressure gradients noninvasively. In comparative invasive studies, it is generally assumed that pressure is effectively uniform distal to the stenosis. As the poststenotic jet expands, however, its velocity decreases, and pressure is recovered to the extent permitted by turbulence, so that the measured gradient will be lower if the distal catheter is positioned downstream from the vena contracta. This can lead to apparent Doppler "overestimation" of the pressure gradient because of this phenomenon of pressure recovery. This study demonstrates that pressure recovery can be important in a variety of clinical settings studied by in vitro models. Although most prominent in streamlined tunnels modeled after the obstruction in patients with hypertrophic cardiomyopathy, these effects are important even for central stenoses at physiologic flow rates. Because precise catheter position is not always known or controlled, these findings suggest an important advantage for Doppler gradient estimation, because it provides the maximal gradient at the vena contracta, which determines the load on the proximal chamber. 相似文献
79.
Safety and immune responses to attenuated Salmonella enterica serovar typhi oral live vector vaccines expressing tetanus toxin fragment C 总被引:1,自引:0,他引:1
Tacket CO Galen J Sztein MB Losonsky G Wyant TL Nataro J Wasserman SS Edelman R Chatfield S Dougan G Levine MM 《Clinical immunology (Orlando, Fla.)》2000,97(2):146-153
Attenuated Salmonella enterica serovar Typhi vaccine strain CVD 908-htrA was used as a vector to deliver fragment C of tetanus toxin as a single-dose oral tetanus vaccine candidate to elicit protective levels of serum tetanus antitoxin. Twenty-one healthy adult volunteers received doses of 1.6 x 10(7) to 8.2 x 10(9) CFU of one of two strains, CVD 908-htrA(pTETnir15) or CVD 908-htrA(pTETlpp), which contained plasmid-encoded fragment C, with sodium bicarbonate, and the safety and immune responses to serovar Typhi antigens and tetanus toxin were assessed. No volunteer had fever or positive blood cultures after vaccination, although diarrhea occurred in 3 volunteers and vomiting in 2 volunteers within 3 weeks after vaccination. Most volunteers excreted the vaccine strain in the first 72 h after vaccination. Three of nine volunteers who received 10(8) CFU or higher doses of the CVD 908-htrA(pTETlpp) construct developed rises in serum antitoxin antibodies. The serum and cellular immune responses to serovar Typhi antigens were less frequent than those previously observed in volunteers who ingested the parent strain CVD 908-htrA. This study demonstrates that fragment C of tetanus toxin delivered orally to volunteers in an S. Typhi vector can elicit protective levels of serum antitoxin. 相似文献
80.
An ideal vaccine has certain biological and physical characteristics. Technological advances have provided new strategies that may help the design of such a vaccine. 相似文献