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71.
72.
In order to draw attention to this rather rare condition affecting all age groups, 4 cases of fibroepithelial polyps of the ureter are reported. Conservative surgery is mandatory after adequate preoperative work-up. The pathological findings, incidence and diagnostic and therapeutic modalities are discussed and some etiological factors proposed. 相似文献
73.
Dr. Robert L. Geggel David R. Fulton Harvey L. Chernoff Richard Cleveland Thomas J. Hougen 《Pediatric cardiology》1987,8(4):279-283
Summary An infant girl is described who had cor triatriatum and partial anomalous pulmonary venous connection of the left pulmonary
veins to the coronary sinus, the first report of this combination of lesions. The infant also had a Dandy-Walker malformation
and multiple facial and intrathoracic hemangiomas. The cardiac diagnosis was made by two-dimensional echocardiography. Cardiac
catheterization and angiography confirmed the findings and also demonstrated a persistent left superior vena cava draining
to the coronary sinus. The infant underwent successful surgical repair. Partial anomalous pulmonary venous connection and
left superior vena cava not infrequently are associated with cor triatriatum. Although two-dimensional echocardiography is
sensitive for the detection of cor triatriatum, preoperative cardiac catheterization is necessary to identify unequivocally
systemic and pulmonary venous connections. 相似文献
74.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
75.
76.
P Pencharz J Beesley P Sauer J Van Aerde U Canagarayar J Renner M McVey D Wesson P Swyer 《The American journal of clinical nutrition》1989,50(6):1395-1400
The effects of nonprotein energy source (ie, glucose only vs glucose and lipid) on nitrogen retention and total-body protein turnover were studied in 20 parenterally fed newborn infants. All infants received approximately 3 g amino acids and 80-90 kcal.kg body wt.d. Total-body protein synthesis was estimated by using three constant-infusion, end-product methods: enrichment of urinary urea and ammonia in response to a [15N]glycine label and exhaled carbon dioxide enrichment in response to a [1-13C]leucine label. No differences were seen in nitrogen retention between the two energy sources. The estimate of total-body protein turnover obtained from the 13C label was similar to that obtained with the [15N]urea label. No differences in turnover rates were observed between the two diet groups. Use of the glucose-plus-lipid fuel system enhanced energy storage and the reutilization of amino acid for protein synthesis. 相似文献
77.
G Harry Van Lenthe Marieke M. M. Willems Nico Verdonschot Maarten C De Waal Malefijt Rik Huiskes 《Acta orthopaedica》2002,73(6):630-637
Although the revision rates for modern knee prostheses have decreased drastically, the total number of revisions a year is increasing because many more primary knee replacements are being done. At the time of revision, bone loss is common, which compromises prosthetic stability. To improve stability, intramedullary stems are often used. The aim of this study was to estimate the effects of a stem, its diameter and the interface bonding conditions on patterns of the bone remodeling in the distal femur.
We created finite element models of the distal half of a femur in which 4 types of knee prostheses were placed. The bone remodeling process was simulated using a strain-adaptive bone remodeling theory. The amount of such remodeling was determined by calculating the changes in bone mineral density in 9 regions of interest from simulated DEXA scans.
The computer simulation model showed that revision prostheses tend to cause more bone resorption than primary ones, especially in the most distal regions. Predicted long-term bone loss due to a revision prosthesis with a thin stem equalled that around a prosthesis with an intercondylar box. However, strong regional differences were found- the stemmed prostheses having more bone loss in the most distal areas and some bone gain in the more proximal ones. A prosthesis with a thick stem led to an increase in bone loss. When the prosthesis-cement interface was bonded, more bone loss was predicted than with an unbonded interface. These results suggest that a stem which increases stability initially may reduce stability in the long term. This is due to an increase in stress shielding and bone resorption. 相似文献
We created finite element models of the distal half of a femur in which 4 types of knee prostheses were placed. The bone remodeling process was simulated using a strain-adaptive bone remodeling theory. The amount of such remodeling was determined by calculating the changes in bone mineral density in 9 regions of interest from simulated DEXA scans.
The computer simulation model showed that revision prostheses tend to cause more bone resorption than primary ones, especially in the most distal regions. Predicted long-term bone loss due to a revision prosthesis with a thin stem equalled that around a prosthesis with an intercondylar box. However, strong regional differences were found- the stemmed prostheses having more bone loss in the most distal areas and some bone gain in the more proximal ones. A prosthesis with a thick stem led to an increase in bone loss. When the prosthesis-cement interface was bonded, more bone loss was predicted than with an unbonded interface. These results suggest that a stem which increases stability initially may reduce stability in the long term. This is due to an increase in stress shielding and bone resorption. 相似文献
78.
Patients at Boston's Children's Hospital diagnosed as having cerebral palsy were filmed walking. These films were digitized and translated into measurements associated with leg motion. In this paper we use the gait measurements of 128 such patients to illustrate that the kth nearest neighbour clustering procedure results in a gait typology for patients with cerebral palsy. The procedure identifies four subpopulations from the sample data; the membership of a patient within this typology is mostly determined by the patient's motor control. The developed typology differs from the present diagnostic system which classifies a cerebral palsy patient as either quadriplegic, diaplegic or hemiplegic. 相似文献
79.
M H Eijgelshoven E R De Kloet D T Van den Berg P L Van Giersbergen 《European journal of pharmacology》1991,205(2):183-189
Evidence indicates that endogenous opioid peptides and glucocorticoids participate in the control of cardiovascular regulation during hemorrhagic shock. In the present study, we investigated a possible interaction between brain opioid peptides and adrenal corticosteroids regarding the control of arterial pressure during hemorrhage. The bleeding volumes required to lower arterial pressure to 80, 60 and 40 mmHg were studied in anesthetized sham-operated (SHAM) and adrenalectomized (ADX) rats. I.c.v. administration of 10 micrograms of naloxone resulted in a significant increase in the bleeding volume required to lower arterial pressure from 60 to 40 mmHg in SHAM animals, whereas no effect of naloxone was observed in ADX animals. Replacement therapy with a 100% corticosterone pellet (100 mg, s.c.), but not with a 12.5% corticosterone pellet (12.5 mg corticosterone and 87.5 mg cholesterol, s.c.), resulted in an effect of naloxone on the bleeding volume in ADX animals. The effect of replacement therapy could be inhibited by i.c.v. pretreatment with the synthetic glucocorticoid receptor antagonist, RU38486 (100 ng). These data suggest that (1) opioid mechanisms are involved in the regulation of blood pressure during hemorrhage, and (2) occupancy of glucocorticoid receptors is required for naloxone to exert its hemodynamic effect during hemorrhagic hypotension in ADX rats. 相似文献
80.
C Peabody J Van Norman L Hollister D Warner 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(1):63-70
1. Twenty-two patients hospitalized for treatment of depression were treated under conditions simulating those of home treatment. 2. Full doses of nortriptyline, from 100 to 150 mg/day, were started after baseline observations were made. 3. Two patients were dropped from the study, one for orthostatic hypotension, one for an aberrant response to nortriptyline. Two additional patients developed orthostasis which was easily managed. Otherwise no unusual side effects were noted. 4. After six days of treatment, 9 of 20 patients showed significant improvement with an overall reduction in scores on the Hamilton Depression Scale of 49% for the entire group. 5. Using the weight-adjusted dosage schedule, 18 of the 21 patients attained plasma concentrations of nortriptyline within the presumed therapeutic range; however, no clear relationship could be established between plasma concentrations and clinical response. 6. With proper selection of patients, it should be possible to treat at home some patients who currently are considered to require hospitalization. 相似文献