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991.
We contrast two statistical methods: three-dimensional cluster analysis and statistical parametric mapping. We show that three-dimensional cluster analysis is based on a neurobiological theory of the regulation of blood flow and, unlike statistical parametric mapping, carries a minimum of assumptions that are tested. Statistical parametric mapping is a formal approach, which is based on a multitude of assumptions of which the majority have not been validated. We also demonstrate that in practice three-dimensional cluster analysis has a reasonable balance between sensitivity and the probability of false positives, giving high reproducibility with data on e.g. colour discrimination.  相似文献   
992.
Low-income minority patients from East St. Louis, Illinois, a depressed midwestern urban city, who had visited acute care settings with asthma symptoms, participated in a focus group. Questions were constructed around the Health Belief Model to characterize participants' experiences in receiving asthma care, their confidence in long-term asthma self-management, barriers they perceived to managing their asthma, and recommendations they would make for improving asthma care in their community. Analysis of comments suggests an appreciable understanding of asthma triggers, limited coping behaviors for asthma symptoms, very limited practice of active asthma management, perception of the health care system as frequently insensitive to their needs or their knowledge of their own care, exchange of well-articulated information regarding how to deal with the system, and an apparent lack of awareness of any potential contribution of patient education or support system.  相似文献   
993.
Multiple pregnancies resulting from ovarian stimulation areat a higher risk of carrying at least one fetus affected byMendelian or chromosomal anomalies, the incidence of which isdirectly related to the order of multiples. Genetic analysisbefore fetal reduction was offered to both high-and low-riskpregnant women carrying two or more fetuses after ovulationinduction. Chorionic villus sampling (CVS) and fetal reductionwere achieved by transabdominal needling. The use of short-termculture, the polymerase chain reaction and fresh tissue enzymaticanalyses have made it possible for genetic diagnosis to be availablein a few days. A total of 100 patients had multifetal pregnancyreduction performed by a single operator; all of them completedpregnancy and none was lost at follow-up. The total fetal lossbefore 24 weeks was 7% and no statistically significant relationshipwas found with the final number of fetuses and CVS. Perinatallosses (3.9%) were only present in the series with a final numberof two fetuses. Pregnancy duration and birthweight were significantlyhigher in singletons than in twins, but were not related toCVS. The rate of chromosomal disorders was higher (7.2%) inthe study series than in singleton pregnancies not undergoingfetal reduction. Diagnostic error due to incorrect samplingwas reported in 1.5% of cases. These data support fetal reductionas a valuable strategy to improve the outcome of multiple pregnancy.The outcome of pregnancies reduced to singletons was significantlybetter than of those reduced to twins, and was not related toCVS. Therefore, prenatal genetic diagnosis should become anintegral part of counselling on multiple pregnancy, and is stronglyrecommended when reduction to singleton pregnancy is requested.  相似文献   
994.
995.
The efficacy of local application of Nitrobid oinment in the treatment of idiopathic sudden sensorineural hearing loss has been presented Overall good to fair recovery occured in 40% of the patients, important prognostic indicators were found to be severity of initial hearing loss, time from onset to initial visit, age of the patient and hearing status of the opposite ear.  相似文献   
996.
H+, K+-ATPase inhibitors such as omeprazole are the antisecretory agents of choice for the management of gastric acid hypersecretory states, including the Zollinger-Ellison syndrome. However, long-term follow-up data on the overall efficacy and safety of these agents in large numbers of patients are lacking. In the current study we examined the long-term efficacy and safety of omeprazole in 116 patients with Zollinger-Ellison syndrome treated with oral omeprazole at a single centre for up to 114 months (mean ± S.E.M. = 38 ± 3 months). The initial omeprazole maintenance dose was established according to the acute upward dose titration method in 89/116 patients (77%). Gastric acid output was effectively controlled using 60 mg of omeprazole once daily in 41/89 patients (46%) and 22/89 patients (25 %) required twice daily omeprazole therapy. The mean ranitidine equivalent dose for patients who required 60 mg omeprazole once daily (2.5 ± 0.2 g/day) was significantly lower than the mean ranitidine equivalent dose for patients who required more than 60 mg omeprazole once daily (4.3 ± 0.3 g/day). Long-term omeprazole maintenance therapy was discontinued in 36/116 patients (31%) but in no cases was discontinuation due either to drug-induced side-effects or uncontrolled gastric acid output. Fasting serum gastrin levels were significantly elevated above pre-treatment levels at only one time point during follow-up and were likely due to tumour growth rather than a drug effect. The final long-term omeprazole maintenance doses were lower than the initial doses but correlated closely with the preomeprazole basal acid output (r= 0.41, P < 0.001) and ranitidine equivalent dose requirements (r= 0.49, P < 0.001). We conclude that omeprazole effectively and safely controls gastric acid hypersecretion in all patients with Zollinger-Ellison syndrome for up to nine years without evidence by tachyphylaxis.  相似文献   
997.
We studied penile blood flow changes with duplex ultrasound scanning in 8 potent young men during the flaccid state and during the erect state induced by visual sexual stimulation. Measured parameters obtained from the cavernous arteries were arterial diameter, peak blood flow velocity and blood flow acceleration. The mean arterial diameter change was 72% associated with average blood flow velocity and acceleration changes of approximately 200%. Actual values for blood flow velocity and acceleration were considerably higher when compared to papaverine-induced values measured in psychogenically impotent men. Visual sexually stimulated penile arterial changes are not analogous to papaverine-induced arterial changes and these differences raise questions about the appropriateness of using psychogenically impotent men as controls for measurement of penile arterial function with duplex scanning.  相似文献   
998.
Diagnostic imaging evaluation of benign prostatic hyperplasia.   总被引:1,自引:0,他引:1  
The optimal evaluation of the patient with symptomatic BPH should include the diagnostic testing necessary to supplement the clinical examination and select a suitable medical, surgical, or interventional therapeutic option. A variety of imaging modalities offer unique but often unnecessary, superfluous, or very expensive information. Rarely is therapeutic intervention for symptomatic BPH denied a patient because of lesions detected with screening imaging tests; it may be only delayed rather than withheld. Virtually all pretreatment IVUs in patients with BPH are normal. Estimates range from 73 to 93 per cent of the studies as normal or having only insignificant findings. Significant pathology, either life-threatening or sufficient to alter or delay treatment, is found between 0.5 and 10 per cent of the time. Upper tract hydronephrosis is the most common finding (3 to 13 per cent). Renal or urothelial cancer prevalence in the patient population with BPH is really no different than in the general population. If signs or symptoms are not present to alert the clinician to some risk factor other than the symptoms of BPH, there is no benefit for routine urography solely for upper tract cancer detection. Furthermore, with the growing use of nonionic contrast media for elderly patients, the cost of the preoperative routine IVU will increase even further as the added charge for contrast ($100 or more) is tacked onto the cost of the study. Azotemic patients are best served by diagnostic ultrasound or by Foley catheter drainage prior to urography when indicated. Ultrasound remains an operator-dependent and technology-limited examination that cannot measure renal function, but the sensitivity and specificity, as well as the overall diagnostic accuracy, are equal to or greater than those of urography for the detection of hydronephrosis, cystic renal masses, and bladder or prostate abnormalities. False-positive ultrasound scans do occur secondary to reflux caused by bladder diverticula, megacalicosis, or other congenital abnormalities. However, these lesions are distinctly rare. Sensitivity for urothelial malignancy is not good, but endoscopic, clinical, and laboratory evaluations should provide adequate pretherapy diagnostic screening. In spite of the preoperative comfort that a normal IVU may give the patient and the operating surgeon, routine intravenous urography for all BPH patients should no longer be considered necessary. Diagnostic ultrasound, either transabdominal or transrectal, also offers the ability to evaluate the kidneys, ureters, and bladder, effectively replacing routine intravenous urography.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
999.
The results of experiments with axial loading of human tibia preparations used for simulation of oblique (spiral) fractures and different methods of osteosynthesis by screws revealed that higher strength was ensured by the method of bone connection with the screws directed perpendicular to the segment axis (4.1 times more than in case of screws directed perpendicular to the plane of fracture). Explanation of the obtained facts necessitated development of more precise biomechanical model of deformation. Practical recommendations have been formulated.  相似文献   
1000.
We report an unusual case of primary cutaneous embryonal rhabdomyosarcoma presenting as a solitary skin lesion on the anterior chest of a 20-month-old child. The tumor was characterized by small, round to oval, poorly differentiated cells. Immunohistochemically, the tumor was negative for NSE, S-100 protein, LCA, and keratin but positive for muscle-specific actin, myoglobin, desmin, and vimentin, thus indicating the presence of myogenous differentiation. Ultrastructural analysis demonstrated thick and thin filaments. Special studies showed no evidence of a primary rhabdomyosarcoma in the patient at a more typical location, nor was there any evidence of metastases.  相似文献   
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