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41.
Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy.  相似文献   
42.
43.
Digital imaging of the chest   总被引:4,自引:0,他引:4  
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.  相似文献   
44.
WNUK-WOJNAR, A.M., ET AL.: Predictors of Ventricular Tachycardia Inducibility in Programmed Electrical Stimulation and Effectiveness of Serial Drug Testing: Polish Multicenter Study. In 100 patients with IHD and complex ventricular arrhythmias, programmed electrical stimulation was performed using up to three extrastimuli at sinus rhythm, and paced 100, 120, and 140 beats/min delivered from the RV apex, outflow tract or the LV with ventricular mapping to evaluate late potentials (LP) in 41 patients. Sustained monomorphic VT (SMVT) was provoked in 91% of 42 patients with a history of VT/VF, p < 0.001, all five patients had SMVT in 24-hour ECG, p < 0.005, and 91% of 21 patients with LV dyskinesis, p < 0.01. After depolarizations were found in 62% of 21 patients with a history of VT, in 58% of 31 patients with inducible VT, p < 0.01 and in five of six patients with LV dyskinesis. In patients with inducible VT, LP had a higher amplitude (105 ± 35 vs 60 ± 47 µV) and were more delayed (202 ± 96 vs 133 ± 75 msec) than in noninducible patients. In 17 patients, serial drug testing was performed after oral administration using mexilitene, disopyramide, chinidine, propafenone, sotalol, and amiodarone. If one drug was tested, the therapy efficacy was 25% if two drugs-60%, and if three drugs-75%. In eight patients, VT was inducible in all tests, but in only one of these patients chronic antiarrhythmic therapy was not effective. We conclude that the most important predictors of VT inducibility are a history of VT or 24-hour ECG, and LV dyskinesis. Serial drug testing is efficient only when many drugs are tested, but even if VT is inducible, it does not exclude the possibility of a good clinical outcome in chronic therapy.  相似文献   
45.
Naratriptan: biological profile in animal models relevant to migraine   总被引:2,自引:0,他引:2  
The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT1B and 5HT1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 193 g kg−1) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 g kg−1). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug.  相似文献   
46.
Overweight has reached alarming proportions among America's youth. Although the cause of the rise in overweight rates in children and adolescents is certainly the result of the interaction of a variety of factors, the presence of vending machines in schools is one issue that has recently come to the forefront. Many states have passed or proposed legislation that limits student access to vending machines in schools or require that vending machines in schools offer healthier choices. The purposes of this study were (a) to assess the food and beverage vending machine offerings in the public school districts in the state of Delaware and (b) to determine whether there are any district vending policies in place other than the current U.S. Department of Agriculture regulations. The results of this study indicate the most commonly sold food and drink items in school vending machines are of minimal nutritional value. School administrators are most frequently in charge of the vending contract, as well as setting and enforcing vending machine policies. Suggestions are offered to assist school nurses, often the only health professional in the school, in becoming advocates for changes in school vending practices and policies that promote the health and well-being of children and adolescents.  相似文献   
47.

Background

Rates of help-seeking for Postnatal Depression (PND) are generally low and population screening has the potential to increase diagnosis rates. Of central importance is the screening instrument's Positive Predictive Value (PPV), which is itself influenced by the prevalence of the condition. When PPV exceeds prevalence, screening defines a screen-positive group with a higher prevalence to which diagnostic-stage procedures can be targeted, a necessary component of a screening program's potential for cost-effectiveness.

Methods

Employing the best available estimates of the prevalence of PND we applied Bayes’ Theorem to map the parameter space for the Positive Predictive Value of the Edinburgh Postnatal Depression Scale (EPDS) across a realistic range of values. Only seven methodologically comparable validation studies are available for major depression and/or minor depression.

Results

Screening with the EPDS always facilitated an increase in identification rates, over the key range of prevalence values. The EPDS defined a sub-group with prevalence between 5-fold and 17-fold greater than the general population. A central estimate of PPV (at a prevalence of 6.8%) was 62%.

Limitations

Few high-quality data are available for analysis and therefore better estimates, of both PND prevalence and of screening accuracy, in the populations where screening takes place are needed.

Conclusions

Our estimates of PPV indicate that population screening with an instrument at least as accurate as the EPDS could successfully increase the number of cases identified and, therefore, treatment rates. Comparisons with the performance of physical health-screening programs appear favourable. Appropriate training for health professionals is essential to minimize potential harms, and following all positive screening results with a formal diagnostic procedure is likely to be useful both clinically and in terms of health system costs.  相似文献   
48.
美国宾夕法尼亚州立大学的2位科学家在性染色体进化变异机制的研究上取得进展。研究发现,Y染色体比X染色体的演化速率快得多,这将导致Y染色体上的基因急剧丢失,如此,Y染色体将会完全消失,人类的传宗接代将受威胁。  相似文献   
49.

Background  

We hypothesize that the prevalence of unknown heart failure in diabetic patients aged 60 years and over is relatively high (15% or more) and that a cost-effective strategy can be developed to detect heart failure in these patients. The strategy is expected to include some signs and symptoms (such as dyspnoea, orthopnoea, pulmonary crepitations and laterally displaced apical beat), natriuretic peptide measurements (Amino-terminal B-type natriuretic peptide) and possibly electrocardiography. In a subset of patients straightforward echocardiography may show to be cost-effective. With information from our study the detection of previously unknown heart failure in diabetic patients could be improved and enable the physician to initiate beneficial morbidity and mortality reducing heart failure treatment more timely.  相似文献   
50.
A 60-year-old man without comorbidity underwent a totally extraperitoneal repair of bilateral inguinal hernias under general anesthesia. Forty minutes after the procedure he developed a slow, shallow respiratory pattern with a respiratory rate of 5/min and a self-limiting grand mal seizure lasting 30 seconds. Arterial blood gas analysis indicated significant hypercarbia and acidosis. The total dose of morphine administered was 20 mg intravenously. Naloxone was administered and the respiratory rate improved. The patient was discharged after 24 hours after making a good recovery and has had no further seizures a year after surgery. Although hypercarbia is a well-known complication of laparoscopic surgery when CO2 is used for insufflation, this, to the best of our knowledge, is the first reported case of a patient sustaining a grand mal seizure resulting from CO2 narcosis after laparoscopic surgery. The possible mechanisms are discussed.  相似文献   
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