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71.
72.
Background: This study examines the notion that gastrointestinal endoscopy performed by supervised surgical residents is safe. Methods: We reviewed all gastrointestinal endoscopic procedures performed by surgical residents with faculty supervision for complications and deaths occurring up to 30 days following the procedures. Results: The overall complication rate for 9,201 upper and lower endoscopy procedures was 1.4% and 0.42%, respectively. Overall mortality rate was 0.76% for upper endoscopy and 0.6% for lower endoscopy. No mortality was a direct result of a procedure-related complication. Intestinal perforation, drug overdose, bleeding, and aspiration were the most common procedure-related complications. Each resident completed an average of 75 upper endoscopies and 79 lower endoscopies during their training period. Conclusions: Gastrointestinal endoscopy can be performed safely by surgical residents with appropriate supervision. The higher morbidity and mortality of upper endoscopy are most likely related to the underlying disease rather than the procedure. Awareness of common complications and application of appropriate precautions and instruction are critical for minimizing complications. Received 25 March 1996/Accepted: 24 April 1996  相似文献   
73.
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   
74.
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   
75.
Specific humoral substances produced and secreted by human tumors that cause hypercalcemia have not been identified. Certain growth factors (such as epidermal growth factor, platelet-derived growth factor, and transforming growth factors-alpha and -beta) have been shown to stimulate the resorption of bone in organ culture by both prostaglandin-dependent and prostaglandin-independent pathways. In this report we demonstrate that epidermal growth factor and recombinant human transforming growth factor-alpha induce a significant rise in plasma calcium concentration when administered repeatedly to intact mice for periods ranging from 24 h to 16 d. The elevation of plasma calcium is not dependent on dietary calcium and is not invariably accompanied by an increase in systemic levels of the prostaglandin E2 metabolite 13,14-dihydro-15-keto-prostaglandin E2. The in vivo calcium-mobilizing activity of epidermal growth factor and transforming growth factor-alpha indicate that these or related growth factors need be considered as potential mediators of tumor-induced hypercalcemia.  相似文献   
76.
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   
77.
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   
78.
79.
N Weidner  J D Levine 《Cancer》1988,62(8):1561-1567
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   
80.
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   
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