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81.
IntroductionAs we progress to an era when patient autonomy and shared decision-making are highly valued, there is a need to also have effective patient-centered communication tools. Radiology reports are designed for clinicians and can be very technical and difficult for patients to understand. It is important for patients to understand their magnetic resonance imaging (MRI) report in order to make an informed treatment decision with their physician. Therefore, we aimed to create a patient-centered prostate MRI report to give our patients a better understanding of their clinical condition.MethodsA prototype patient-centered radiology report (PACERR) was created by identifying items to include based on opinions sought from a group of patients undergoing prostate MRI and medical experts. Data was collected in semi-structured interviews using a salient belief question. A prototype PACERR was created in collaboration with human factors engineering and design, medical imaging, biomedical informatics, and cancer patient education groups.ResultsFifteen patients and eight experts from urology, radiation oncology, radiology, and nursing participated in this study. Patients were particularly interested to have a report with laymen terms, concise language, contextualization of values, definitions of medical terms, and next course of action. Everyone believed the report should include the risk of MRI findings actually being cancer in the subsequent biopsy.ConclusionsA prostate MRI PACERR has been developed to communicate the most important findings relevant to decision-making in prostate cancer using patient-oriented design principles. The ability of this tool to improve patient knowledge and communication will be explored.  相似文献   
82.
This three-part series of articles summarizes the uses of several devices or groups of devices intended for the diagnosis or treatment of temporomandibular disorders (TMD) and compares their claimed clinical usefulness with the present scientific evidence. Part I of this review defines TMD; discusses the principal criteria for evaluating published scientific clinical evidence such as reliability, validity, sensitivity, and specificity; gives a rationale for the clinical "gold standard" against which diagnostic and therapeutic devices must be compared; and evaluates the status of jaw tracking for the diagnosis of TMD. This review and evaluation led to the conclusion that, at the present time, the claim that jaw-tracking devices have a diagnostic value for TMD is not well supported by the scientific evidence.  相似文献   
83.
We have used small injections of biocytin to label and comparepatterns of intreareal, laterally spreading projections of pyramidalneurons in a number of areas of macaque monkey cerebral cortex.In visual areas (V1, V2, and V4), somatosensory areas (3b, 1,and 2), and motor area 4, a punctate discontinuous pattern ofconnections is made from 200-µm-diameter biocytin injectionsin the superficial layers. In prefrontal cortex (areas 9 and46), stripe-like connectivity patterns are observed. In allareas of cortex examined, the width of the terminal-free gapsis closely scaled to the average diameter of terminal patches,or width of terminal stripes. In addition, both patch and gapdimensions match the average lateral spread of the dendriticfield of single pyramidal neurons in the superficial layersof the same cortical region. These architectural features ofthe connectional mosaics are constant despite a twofold differencein scale across cortical areas and different species. They thereforeappear to be fundamental features of cortical organization.A model is offered in which local circuit inhibitory "basket"interneurons, activated at the same time as excitatory pyramidalneurons, could veto pyramidal neuron connections within eithercircular or stripe-like domains; this could lead to the formationof the pattern of lateral connections observed in this study,and provides a framework for further theoretical studies ofcerebral cortex function.  相似文献   
84.
Summary One-hundred and seventy patients with estrogen receptor positive (10 pmol/g protein) advanced breast cancer have been treated in a prospective randomized study either with continuous tamoxifen 30 mg × 1 daily (TAM), or with TAM 30 mg × 1 daily for 8 weeks alternating with medroxyprogesterone acetate 500 mg × 2 daily for 8 weeks (TAM/HD-MPA). The response rate was 62% in the group treated with cyclic TAM/HD-MPA versus 41% in the TAM alone group (p = 0.02). There was no significant difference in duration of remissions or survival.  相似文献   
85.
Purpose. There are, in general, few published series on chordoma. It is a rare disease and further data are still needed.Patients/methods. The data of 37 patients with chordoma were retrospectively analyzed. Treatment was surgical excision in 11, radical radiotherapy in 9 and a combination of the two in 16 cases. The male to female ratio was 2.7 : 1. Median age was 59 years (range 1-89 years).Results. The most common symptoms at diagnosis were pain (98%), neurological disturbances (42%) and incontinence (33%). The tumours were located in the sacro-coccygeal region in 68%, the spheno-occipital region in 16% and the vertebrae in 16% of the patients. Median tumour.size was 7 cm (range 1-30 cm). Local recurrence occurred in 21/36 treated cases and distant metastases developed in eight patients (23%). The median time to recurrence/progression after primary treatment was 2 years (range 1-10 years). The actuarial 5-year rates of overall, progression-free and symptom-free survival were 40%, 31% and 20%, respectively. The corresponding 10-year rates were 26%, 21% and 14%, respectively. At the time of analysis, seven patients were alive, six without evidence of disease. Four of the six patients without active disease were symptom free. A univariate analysis showed that age, sex, tumour size, histopathology, surgical safety margin, treatment modality and radiation dose did not significantly affect overall, progression-free or symptom-free survival. Only turnout site had a prognostic value with turnouts in the spheno-occipital region carrying the worst prognosis.Discussion. We conclude that effective treatment against chordomas is still lacking and a prospective multi-institutional registration study may provide more information on the optimal work-up and treatment of this rare disease.  相似文献   
86.
The effects of caffeine on cytoplasmic Ca2+ oscillations induced by carbachol and guanosine 5-O-(3-thiotriphosphate) (GTP--S) were studied in individual mouse pancreatic ß-cells clamped at a hyperpolarized potential. Addition of 10 mM caffeine did not affect the cytoplasmic Ca2+ concentration ([Ca2+]1) in ß-cells exposed to 20 mM glucose and hyperpolarized with diazoxide. Under similar conditions 100 M carbachol induced a typical response with a marked [Ca2+]i peak followed by a lower sustained elevation. Irrespective of whether 10 mM caffeine was present, there were [Ca2+]i transients with frequencies of 1–5/min superimposed on the sustained phase in 50–60% of the cells. In previously non-exposed cells the introduction of 10 mM caffeine caused temporary lowering of the sustained phase with disappearance of the transients. Subsequent omission of caffeine in the continued presence of carbachol caused a marked [Ca2+]i peak followed by reappearance of the [Ca2+]i, transients. However, in cells oscillating in the presence of caffeine its omission caused disappearance of the transients. In this case reintroduction of caffeine restored the transients.In cells kept at –70 mV by a patch pipette containing 100 M GTP--S and 3 mM Mg-ATP there were [Ca2+]i transients with frequencies of 0.5–2.5/min. These transients were sufficiently pronounced to activate repetitively a K+ current. Addition of 10 mM caffeine caused disappearance of the [Ca2+]i transients or reduction of their amplitudes and frequencies.The results indicate that caffeine does not activate Ca2+-induced Ca2+ release in hyperpolarized ß-cells but inhibits the Ca2+-mobilizing effect of inositol 1,4,5-trisphosphate. Correspondence to: E. Gylfe at the above address  相似文献   
87.
88.
BACKGROUND AND OBJECTIVE: Simultaneous irradiation and viewing of 10-120 microm cutaneous blood vessels were performed to investigate the effects of 2-micros 577-nm dye laser pulses. STUDY DESIGN/MATERIALS AND METHODS: A modified scanning laser confocal microscope recorded vessel response to different radiant exposures (J/cm2). Probit analysis determined the 50% probability ("threshold") radiant exposure necessary to cause embolized or partly occluding coagula, coagula causing complete blood flow stoppage, and hemorrhage. RESULTS: A statistically significant difference in the threshold radiant exposure existed for each damage category for blood vessels 10-30 microm in diameter, but not for larger vessels. For vessels over 60 microm, complete flow stoppage was unattainable; increasing laser pulse energy produced hemorrhage. In larger vessels, coagula often were attached to the superficial vessel wall while blood flowed underneath. Monte Carlo optical and finite difference thermal modeling confirmed experimental results. CONCLUSION: These results provide insight into the role of pulse duration and vessel diameter in the outcome of pulsed dye laser irradiation.  相似文献   
89.
Background: The feasibility study described herein was prompted by a report in 1992 of possible reproductive and developmental health concerns among female workers in a Russian nickel refinery. Objective: The primary goal was to ascertain whether medical, statistical, and occupational data bases could be accessed for information about the pregnancy histories, occupational histories, and life-style factors of the women affected. Methods: The project was facilitated by construction of a registry of all births in three towns with a nickel refinery and verification of its contents against patients' records obtained from hospital delivery and gynecology departments and community polyclinics. Municipal Registration Board, Regional Health Statistics Board, and nickel company records were also reviewed. Results: Reproductive/developmental outcome information and workplace histories were acceptable. Sample-size calculations indicated that a cohort or cross-sectional study would be amenable and suitable for the detection of an excess risk for spontaneous abortion with adequate statistical significance and power. Such investigations would need to be supplemented by workplace environmental/biological monitoring assessments for evaluation of exposure to occupational hazardous factors and a worker's questionnaire to obtain information about life-style factors. A case-control design is recommended for the study of congenital defects. Conclusions: A well-designed, comprehensive epidemiology study is technically feasible because of the availability of a favorable pool of study subjects, reproductive/developmental outcome data, information to control for major confounders, and suitable occupational records. Received: 13 July 1998 / Accepted: 7 February 1999  相似文献   
90.
We report results of numerical simulations for a model of generation of orientation selectivity in macaque striate cortex. In contrast to previous models, where the initial orientation bias is generated by convergent geniculate input to simple cells and subsequently sharpened by lateral circuits, our approach is based on anisotropic intracortical excitatory connections which provide both the initial orientation bias and its subsequent amplification. Our study shows that the emerging response properties are similar to the response properties that are observed experimentally, hence the hypothesis of an intracortical generation of orientation bias is a sensible alternative to the notion of an afferent bias by convergent geniculocortical projection patterns. In contrast to models based on an afferent orientation bias, however, the "intracortical hypothesis" predicts that orientation tuning gradually evolves from an initially nonoriented response and a complete loss of orientation tuning when the recurrent excitation is blocked, but new experiments must be designed to unambiguously decide between both hypotheses.  相似文献   
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