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W. de Riese E. B. Walker C. de Riese T. M. Ulbright W. N. Crabtree J. Messemer J. A. Jones A. Hinkel R. S. Foster J. P. Donohue T. Senge 《Urological research》1994,22(4):213-220
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only. 相似文献
95.
This study of a series of 40 mildly head injured (concussed) patients suggests that different physiologic pathways underlying the tests done in a six-part resting EEG, and for the 11 evoked electrical potential shifts occurring in the cerebral terrain, are testable. Further work seems likely in order to ascertain which clinical signs and symptoms may be related to specific individual types of recorded electronic brain imaging (EBI) abnormality. Which of the 11 parameters studied, EEG, VER, AER, and SER, would be more or less likely to be abnormal in their individual patterns (as being deviant from normal controls) also remains to be defined. The relationship of these neurophysiologic abnormalities to certain postconcussive symptoms, i.e., headache, dizziness, blurred vision, etc., at this point in time remains to be evaluated more precisely. The authors suggest that further research is necessary in evaluating the clinical use of somatosensory evoked responses as an additional parameter in electronic brain imaging (EBI) technology. 相似文献
96.
M A MacLean R Wilson J A Thomson S Krishnamurthy J J Walker 《European journal of obstetrics, gynecology, and reproductive biology》1992,43(3):167-172
During pregnancy the mother must tolerate intra-uterine allogenic fetal tissue. Failure of this tolerance may cause spontaneous abortion. The immunological changes occurring in normal pregnancy are poorly understood. The aim of this study was to investigate the immunological changes occurring in pregnancy. Thirty women in the first trimester; 10 in the second and 10 in the third trimester of pregnancy were studied and compared to age matched non-pregnant controls. In normal pregnancy there was an increase in the total white cell count with no change in the lymphocyte count. There was a fall in total T cell numbers and activated T cell numbers, with no change in helper/inducer or suppressor/cytotoxic T cell numbers. [3H]Thymidine uptake in response to three different mitogens was increased. This implies an increase in potential for the cells to respond to mitogens. There was no change in interleukin-2 receptor levels, suggesting that despite this increased potential there was no general activation of the immune system. A rise in IgM and IgG was found after mitogen stimulation of peripheral blood lymphocytes, suggesting an increase in potential antibody production. These results demonstrate that lymphocytes from pregnant women have an increased potential rather than an increased activity. 相似文献
97.
S Young Yim S Young Yim W O Walker J F McLaughlin 《Zeitschrift für Kinderchirurgie》2004,14(2):108-111
The clinical records of twenty-five children with exstrophy of the cloaca (EC) were retrospectively reviewed to evaluate the prevalence and the clinical characteristics of iron deficiency anemia (IDA). Five of the 25 children with EC (20 %) exhibited IDA at some point. Their ages at the time of diagnosis were between 1.9 and 13.0 years. In the four cases where IDA was thought to be related to iron malabsorption secondary to short-bowel syndrome, its treatment required longer periods of iron supplementation to correct the anemia and to restore the total body iron stores. Physicians caring for children with EC should monitor for and treat IDA as part of a comprehensive management plan. 相似文献
98.
Vijay A Mittal Shivali Dhruv Kevin D Tessner Deborah J Walder Elaine F Walker 《Neuropsychopharmacology》2007,61(10):1179-1186
BACKGROUND: Evidence suggests that prenatal insult may play a role in the etiology of psychotic disorders. Minor physical anomalies (MPA) are an indicator of abnormal fetal development and are elevated in individuals at genetic and behavioral risk for psychosis. Yet, there has been little empirical research on the relationships between MPAs and other neurobiological risk indicators. We hypothesized that the frequency of MPAs (an external marker of prenatal central nervous system [CNS] disruption) would be associated with two other biomarkers suggestive of disruptions in fetal neurodevelopment: movement abnormalities (an indicator of striatal abnormalities) and heightened cortisol secretion (an indicator of hypothalamic-pituitary-adrenal [HPA]/hippocampal function). METHODS: Participants with schizotypal personality disorder (SPD; n = 39) and both normal (n = 47) and other personality disorders (n = 28) control subjects were administered structured diagnostic interviews and assessed for MPAs, movement abnormalities, and salivary cortisol. RESULTS: Schizotypal personality disorder participants showed significantly greater MPAs and movement abnormalities and higher cortisol than both the normal and other personality disorders groups. Hierarchical linear regression analyses revealed that higher rates of MPAs were linked with greater movement abnormalities and salivary cortisol. CONCLUSIONS: The findings suggest that MPAs serve as a marker of neurodevelopmental abnormalities that affect striatal and hippocampal regions. 相似文献
99.
Kristin Fraser Adam Peets Ian Walker Janet Tworek Michael Paget Bruce Wright & Kevin McLaughlin 《Medical education》2009,43(8):784-789
Context Prior research has demonstrated that residents have poor clinical skills in cardiology and respirology. It is not clear how these skills can be improved because the number of patients with suitable clinical findings whose cooperation might help residents to better develop these clinical skills is limited.
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
100.
Bastiaan Driehuys Julia Walker Jim Pollaro Gary P Cofer Nilesh Mistry David Schwartz G Allan Johnson 《Magnetic resonance in medicine》2007,58(5):893-900
In the study of asthma, a vital role is played by mouse models, because knockout or transgenic methods can be used to alter disease pathways and identify therapeutic targets that affect lung function. Assessment of lung function in rodents by available methods is insensitive because these techniques lack regional specificity. A more sensitive method for evaluating lung function in human asthma patients uses hyperpolarized (HP) (3)He MRI before and after bronchoconstriction induced by methacholine (MCh). We now report the ability to perform such (3)He imaging of MCh response in mice, where voxels must be approximately 3000 times smaller than in humans and (3)He diffusion becomes an impediment to resolving the airways. We show three-dimensional (3D) images that reveal airway structure down to the fifth branching and visualize ventilation at a resolution of 125 x 125 x 1000 microm(3). Images of ovalbumin (OVA)-sensitized mice acquired after MCh show both airway closure and ventilation loss. To also observe the MCh response in naive mice, we developed a non-slice-selective 2D protocol with 187 x 187 microm(2) resolution that was fast enough to record the MCh response and recovery with 12-s temporal resolution. The extension of (3)He MRI to mouse models should make it a valuable translational tool in asthma research. 相似文献