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11.
Theodore Colton Laurence Freedman Tony Johnson David MaChin 《Statistics in medicine》1989,8(6):639-639
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Immunosuppressed persons are at greater risk of developing malignancies. In human immunodeficiency virus (HIV) immunosuppression the most common oral cancers are Kaposi's sarcoma and non-Hodgkin's lymphoma. Squamous cell carcinoma has also been reported to be associated with HIV disease. Kaposi's sarcoma is the most frequent neoplastic disease in acquired immunodeficiency syndrome and is by far the most common in the head and neck area. This article reviews the prevalence, clinical features, and management of these diseases in HIV infection. 相似文献
14.
The health of a team participating in the 1990 World Solar Car Challenge was recorded for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlations between increasing maximum temperatures and emotional reaction scores. The morbidity records and perceived health scores reflect the conditions of the race. Twenty-five per cent of full-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems of the team. 相似文献
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A M Glasgow J Weissberg-Benchell W D Tynan S F Epstein C Driscoll J Turek E Beliveau 《Pediatrics》1991,88(1):98-104
The characteristics of children with diabetes readmitted to Children's Hospital during a 5-year period, 1984 to 1989, were compared with those characteristics of new-onset patients admitted for stabilization and education and to outpatients in the Children's Hospital diabetes program to determine which characteristics were associated with patients who were readmitted. Changes in the frequency of readmissions were examined to determine whether the introduction of a diabetes team and a program that emphasizes the importance of ensuring that patients at risk of readmission consistently received insulin injections resulted in a reduction of readmissions. Readmissions occurred more frequently in patients who were black (71% compared with 38% of new-onset patients and 31% of outpatients) (P less than .001), from one-parent homes (56% compared with 27% of new-onset patients and 24% of outpatients) (P less than .001), and without third-party insurance (45% compared with 18% of new-onset patients and 15% of outpatients) (P less than .001). Readmissions were very common at 14 to 15 years of age (39% of readmissions vs 18% of outpatients) and very uncommon in children younger than age 9 (6% of readmissions vs 27% of outpatients) (P less than .001). Fewer readmissions for ketoacidosis occurred in the summer than in any other season (P less than .05). Readmissions fell by 47% over the 5-year period while new-onset patients increased by 85%. The reduction in frequency of readmissions was due to fewer readmissions for ketoacidosis and fewer readmissions in blacks, in patients from one-parent homes, and in patients without third-party insurance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Juan F López-Giménez Laurence H Tecott José M Palacios Guadalupe Mengod M Teresa Vilaró 《Journal of neuroscience research》2002,67(1):69-85
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors. 相似文献
19.
A theoretical algorithm for shaping the signal response during the approach to steady state in three-dimensional magnetization-prepared rapid gradient-echo (3D MP-RAGE) pulse sequences has been developed and implemented. This algorithm derives the flip angle series required to produce specifically chosen time evolutions of the signal intensities during the data acquisition segment of 3D MP-RAGE sequences. Theoretical predictions for the cases of unshaped, uniform, and mono-exponential decay signal responses were quantitatively validated with a doped-water phantom on a 1.5-T whole-body imager and in all cases there was excellent agreement between the theoretical and experimental values. The effects of RF inhomogeneities and eddy currents on the signal response shaping were also investigated. To demonstrate the potential utility of the technique, the signal response shaping algorithm was applied to a T1-weighted 3D MP-RAGE sequence to derive the acquisition flip angle series which theoretically yields the maximum white matter/gray matter signal difference (WGSD) consistent with the chosen response shape. Images obtained from a healthy volunteer using this variable flip angle sequence were compared with 3D RF-spoiled steady-state gradient-echo images obtained in the same total imaging time. The 3D MP-RAGE images demonstrated a 41% increase in the WGSD-to-noise ratio. These initial very promising results indicate that with further refinement to eliminate some intensity artifacts, the variable flip angle 3D MP-RAGE technique may, with respect to certain image properties, provide considerable improvements over currently available 3D gradient-echo imaging techniques. 相似文献
20.
A Rahmouni A Yang C M Tempany T Frenkel J Epstein P Walsh P K Leichner C Ricci E Zerhouni 《Journal of computer assisted tomography》1992,16(6):935-940
More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume. 相似文献