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91.
The purpose of this study was to describe the role played by the ability to estimate caries depth in successfully deciding to treat dentin caries when making use of bitewing radiographs as a diagnostic test. A 10% random sample (n = 444) of Dutch dental practitioners was sent a two-wave questionnaire concerning radiographic caries diagnosis and restorative treatment decision making. The second wave consisted of simulated bitewing radiographs of 105 tooth surfaces with and without dentin caries according to two measuring standards: (a) a micro-radiographic "gold" standard and (b) a norm of expert observers. The dentists were asked to diagnose caries at 4 depths of penetration using a 5-point certainty scoring system to measure diagnostic ability; and to make a treatment decision for each surface. The overall response was 61% (273). A regression analysis was carried out using the chance per dentist of correctly deciding to treat dentin caries as the dependent variable. The degree of agreement with the experts' diagnosis of radiographic caries depth was used to create variables measuring diagnostic ability. Five significant (P less than 0.05) variables explained 60% (R2 = 0.60) of the variation in decision making. The best diagnostic ability variable explained 47% of the variation while the treatment criterion reportedly used explained 3%. We conclude that the ability of practitioners to interpret radiographs plays a major role in treatment decision making and that their reported treatment decision making criteria should not be taken at face value.  相似文献   
92.
The authors examined reports addressing the question of whether electroconvulsive therapy (ECT) is more effective in psychotic or nonpsychotic depressive disorders. Most ECT studies did not consider the issue directly, and those that did had varying methodologies and results. The authors then analyzed the data of 33 depressed patients to clarify the differential response to ECT in 13 psychotic and 20 nonpsychotic patients. The subjects were also examined as to type of electrode placement. ECT produced a greater reduction in Hamilton Depression Rating Scale scores in the psychotic depressives as compared to the nonpsychotics after an average of 9.2 treatments. The two patients who were nonresponders to ECT were both nonpsychotic.  相似文献   
93.
While it is often assumed that objects can be recognized irrespective of where they fall on the retina, little is known about the mechanisms underlying this ability. By exposing human subjects to an altered world where some objects systematically changed identity during the transient blindness that accompanies eye movements, we induced predictable object confusions across retinal positions, effectively 'breaking' position invariance. Thus, position invariance is not a rigid property of vision but is constantly adapting to the statistics of the environment.  相似文献   
94.
Rats with lesions of the area postrema (APX) are known to exhibit an enhanced intake of highly palatable foods such as sweetened condensed milk and cookies. These observations suggest the possibility that APX rats find these foods more rewarding and will work harder to obtain these foods. Sham and APX rats were tested on fixed ratio (FR) and progressive ratio (PR) schedules. APX rats consistently pressed more times to receive sucrose solution and attained both FR 3 and FR 5 criteria significantly faster than sham-lesioned control rats. Furthermore, rats with APX had significantly higher break points than sham-lesioned control rats on a progressive ratio schedule. These results support the hypothesis that rats with lesions of the area postrema will consistently work harder to obtain a highly palatable food reward.  相似文献   
95.
This review considers the pathologic features of endometrioid carcinoma of the uterine corpus, which accounts for approximately 80% of endometrial adenocarcinomas, with an emphasis on its histologic features, recent advances, and problematic aspects. In addition to typical endometrioid carcinoma, the variants of endometrioid carcinoma covered include secretory carcinoma, villoglandular endometrioid carcinoma, endometrioid carcinoma with small nonvillous papillae, endometrioid carcinomas with microglandular and sertoliform patterns, and endometrioid carcinomas with metaplastic changes. These changes include a variety of different appearances of squamous epithelia (ranging from mature and keratinizing to immature with only subtle evidence of a squamous nature), clear cells, surface changes resembling syncytial metaplasia or microglandular hyperplasia, ciliated cells, oxyphilic cells, and spindled epithelial cells (sarcomatoid carcinoma). The last is one of several variants that may cause a biphasic appearance, all of which should be distinguished from the malignant müllerian mixed tumor. Rare findings in endometrioid carcinomas include hyalinization, psammoma bodies, and foci of stromal metaplasia such as osteoid. Unusual growth patterns of endometrioid carcinomas include involvement of adenomyosis, the "diffusely" infiltrating pattern of myoinvasion, and a previously unemphasized pattern of myoinvasion with "pinched off" glands that may be cystic or have a pseudovascular appearance, often with a myxoid stromal reaction. Other aspects of endometrioid carcinoma discussed are its immunoprofile, grading, cervical involvement (including a hitherto undescribed "burrowing" pattern of extension within the cervix that can result in underdiagnosis of stage IIB disease), carcinoma arising in the lower uterine segment, carcinoma arising in polyps and adenomyomas, carcinoma in young women, tamoxifen-related carcinoma, associated ovarian endometrioid carcinoma, and peritoneal keratin granulomas. Finally, the differential diagnosis of endometrioid carcinoma is briefly considered with a section on benign mimics, including curettage-related changes, menstrual changes, adenomyosis-related problems, metaplastic changes, atypical polypoid adenomyoma, radiation atypia, and papillary proliferations, and a section on metastatic colonic carcinoma.  相似文献   
96.
A community sample of 1106 adults was examined to assess the impact of the doctor-patient relationship on participants' avoidance of treatment for a recognized medical or psychological problem. Of five aspects of participants' previous experience with their physicians, all but waiting time predicted participants' self-reported treatment avoidance. In two logistic regression models participants who felt their physicians listened more to their concerns were less likely to avoid treatment for both medical and psychological problems during the previous 12 months. These findings suggest that patients' perceptions of how they are treated by physicians may help explain why many people delay or avoid healthcare treatment, even when faced with a significant health problem.  相似文献   
97.
Highly malignant cell lines and low-malignant cell lines isolated from three different methylcholanthrene-induced murine fibrosarcomas were examined for their ability to attach to plastic dishes and collagen-coated dishes under serumfree conditions and in the presence of serum. Most of the cells from the three highly malignant lines attached and spread under all conditions. By 72h, there was a significant increase in the number of cells indicating that at least some of the cells had undergone division (even in the absence of serum). In contrast, fewer of the cells from the three low-malignant lines attached and spread on the plastic or collagen substrates in the absence of serum or in the presence of 0.1 per cent serum. However, when 15g laminin per dish was added along with the lowmalignant cells, they then attached and spread on the plastic and collagen-coated dishes. Previous studies have indicated that the highly malignant lines express cell surface antigens that cross-react with laminin while the low-malignant cell lines do not. We speculate that the differences between the high- and low-malignant cells in the expression of cell surface laminin-like antigens contribute to the dissimilarities in attachment and spreading capacity. These differences may also contribute to the dissimilarity between these cells in malignant potential.  相似文献   
98.
Physical illness is a life experience which challenges an individual'ssense of control and thus represents a potential threat to mentalhealth. For children, a serious illness threatens not only theirsense of physical and psychological well-being but also threatensthe psychological well-being of their family. In this study,severely ill patients (n = 15) and a member of their family(n = 15) were interviewed. The patients, who ranged in age from12 to 21 years, were being treated for metastatic solid tumorsor lymphoma that failed to respond to conventional therapeuticregimens. Correlates of control for the patients and familymembers, the relationship between control and developmentalstage of the patients, and the difference between levels ofcontrol in patients and family member were examined. The findingsare discussed in relation to development and their implicationsfor medical management.  相似文献   
99.
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS.  相似文献   
100.
The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent. This potentiating effect was still present at saturating concentrations of acetylcholine, and no changes in single-channel conductance or reversal potential were observed, thus suggesting a modification in the gating of alpha4beta2 receptors. Dwell time analysis of single channel records indicates that the mechanism of action of deformylflustrabromine could be both an increase of the opening rate constant and a decrease of the closing rate constant on alpha4beta2 receptors. Thus, deformylflustrabromine may constitute an excellent starting point for the future development of related agents able to potentiate human neuronal nicotinic receptor function.  相似文献   
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