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151.
Beverly Barton Rogers John Sommerauer Albert Quan Charles F. Timmons D. Brian Dawson Richard H. Scheuermann Karen Krisher Carolyn Atkins 《Pediatric and developmental pathology》1998,1(6):480-486
To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates
with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending
July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%)
were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a
lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients
with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result
at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%)
of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low
serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large
viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment
for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may
be used to monitor response to therapy for the disorder.
Received August 26, 1997; accepted January 13, 1998. 相似文献
152.
Black tea and mammary gland carcinogenesis by 7,12- dimethylbenz[a]anthracene in rats fed control or high fat diets 总被引:3,自引:1,他引:3
Epidemiological studies suggest that tea may reduce cancer risk, and in
laboratory rodents, chemopreventive effects of tea or purified extracts of
tea have been demonstrated in lung, gastrointestinal tract and skin. There
is some evidence of chemoprevention by tea in the mammary gland, but the
data are not conclusive. In order to evaluate more fully the possible
influence of black tea on 7,12-dimethylbenz[a]anthracene (DMBA)-induced
mammary gland tumors in the female S-D (Sprague-Dawley) rat, three large
studies were performed: experiment 1, tumorigenesis in rats fed AIN-76A
diet and given 25 mg/kg DMBA and 1.25 or 2.5% whole tea extract or water to
drink; experiment 2, tumorigenesis in rats given 15 mg/kg DMBA and the same
diet and fluids as in experiment 1; experiment 3, tumorigenesis in rats fed
control or HF (high fat, corn oil) diet and given 15 mg/kg DMBA and 2% tea
or water to drink. Tea was given throughout the experiment; DMBA was given
by gastric gavage at 8 weeks of age. There was no consistent effect of tea
on tumorigenesis in rats fed AIN-76A diet; there was, however, evidence in
experiment 3 of a reduction of tumorigenesis by tea in rats fed the HF
diet. In experiment 3, rats fed the HF diet and given water showed the
expected increase in tumor burden (number and weight) compared with rats
fed control diet. However, rats fed the HF diet and given 2% tea showed no
increase in tumor burden; their tumor burden was significantly lower than
in rats fed the HF diet and given water (P < 0.01) and was not different
from rats fed control diet and given water or tea. In addition, in
experiment 3, the number of malignant tumors per tumor- bearing rat was
increased by the HF diet in water-drinking rats (P < 0.01) but not in
tea-drinking rats. Therefore, it appears that tea partially blocked the
promotion of DMBA-induced mammary tumorigenesis by the HF diet.
相似文献
153.
Relatively little is still known about the sense of taste, or contact chemoreception, compared with other sensory modalities, despite its importance to many aspects of animal behaviour. The central projections of the sensory neurons from bimodal contact chemoreceptors (basiconic sensilla) were compared with those from mechanosensory tactile hairs located on similar regions of the middle leg of the locust. Basiconic sensilla are multiply innervated, containing one mechanosensory and several chemosensory neurons, whereas tactile hairs are innervated by a single mechanosensory neuron. We show that the sensory neurons from tactile hairs form a complete 3-dimensional somatotopic map in the mesothoracic ganglion. Sensory neurons from hairs located on the coxa projected to a region near the midline of the ganglion with neurons from hairs located on progressively more distal parts of the leg arborizing in successively more lateral regions of neuropil. All the neurons from basiconic sensilla, both mechanosensory and chemosensory, also projected in a similar, strictly somatotopic, manner, and the arbors from these neurons overlapped considerably with those from tactile hairs on equivalent parts of the leg to form a continuous region. Thus, the position of a receptor on the leg is preserved in the central nervous system not only for the mechanosensory neurons from both tactile hairs and basiconic sensilla but also for chemosensory neurons. We could observe no anatomical features or small differences in projection region between sensory neurons from individual basiconic sensilla consistent with differences in modality. 相似文献
154.
The impact of external feedback on computer-assisted learning for surgical technical skill training 总被引:4,自引:0,他引:4
BACKGROUND: Computer-assisted learning (CAL) offers a number of potential advantages for surgical technical skills teaching. The purpose of this study was to evaluate the impact of individualized external feedback on surgical skill acquisition when a CAL package is used for instruction. METHODS: Freshman and sophomore students participated in a 1-hour CAL session designed to teach them how to tie a two-handed square knot. One group received individualized external feedback during the session and the other group did not. Subjects were videotaped performing the skill before and after the session. The tapes were independently analyzed, in blinded fashion, by three surgeons. Three measures were obtained: the total time for the task, whether or not the knot was square, and the general quality of the performance using a rating scale. RESULTS: Data from 105 subjects were available for final analysis. For both groups there were significant increases in the proportion of knots that were square when the posttest performance was compared with the pretest performance but there was no difference between groups on this measure. Comparison of the performance scores demonstrated that both groups had a significant improvement after the session but the performance scores were significantly better in the group that had received feedback. CONCLUSIONS: Novices in both groups using CAL showed improvement in two of the outcomes measured, suggesting that subjects in both groups attained some degree of competence with this skill. The higher posttest performance score for the group receiving feedback demonstrates that external feedback results in a higher level of mastery when CAL is used to teach surgical technical skills. 相似文献
155.
Shafizadeh S McEvoy JR Murray C Baillie GM Ashcraft E Sill T Rogers J Baliga P Rajagopolan PR Chavin K 《The American surgeon》2000,66(12):1132-1135
The current disparity of viable organs and patients in need of a transplant has been an impetus for innovative measures. Live donor renal transplantation offers significant advantages compared with cadaveric donor transplantation: increased graft and patient survival, diminution in incidence of delayed graft function, acute tubular necrosis (ATN), and reduction in waiting time. Notwithstanding these gains live donors continue to be underutilized and account for only approximately one quarter of all renal transplants performed in the United States. It has been felt that inherent disincentives to live donation have slowed its growth. These include degree and duration of postoperative pain and convalescence, child care concerns, cosmetic concerns, and time until return to full activities and employment. In an attempt to curtail the disincentives to live donation, laparoscopic live donation (laparoscopic donor nephrectomy; LDN) was developed. The purpose of this study was to compare the results of our first 25 laparoscopic nephrectomies (performed over a 10-month period from September 1998 through July 1999) with the previous 25 standard open donor nephrectomies (ODNs) completed over the past 3 years. We conducted a retrospective review of all donor nephrectomies and recipient pairs performed over the past 3 years. End points included sex, operative time, length of stay, immediate and long-term renal function, and willingness to donate. There were no differences in demographics of the ODN versus the LDN group. The average length of stay was 2.48+/-0.72 days for the LDN versus 4.08+/-0.28 days for the ODN. ODN and LDN have comparable short- and long-term function with no delayed graft function and no complications. Growth of living donor transplant has increased from 16 per cent of all kidney transplants performed in 1995 to 23 per cent in 1999. We conclude that LDN is a viable alternative to the standard donor operation. LDN has had a positive impact on the donor pool by minimizing disincentives to live donation. With the initiation of our laparoscopic program the number of LDNs has increased. Presently the live donor pool is the most viable alternative to significantly increase the number of kidneys for transplantation. 相似文献
156.
Speech and swallowing are important components of health‐related quality of life following head and neck cancer treatment. The aim of this study was to demonstrate the value of prospective multi‐centre evaluation by Speech and Language Therapists and to compare health‐related quality of life with speech and swallowing impairments. The University of Washington Head and Neck questionnaire version 4 (UW‐QOL) and Therapy Outcome Measures (TOM) were rated before and 6 months after cancer treatment in 95 patients from 12 centres. There was deterioration in TOM scores at 6 months. Pretreatment UW‐QOL swallowing was ranked equal first, with speech fourth. At 6 months speech was first and swallowing second. There were positive correlations between UW‐QOL swallowing and TOM dysphagia and between UW‐QOL speech and TOM laryngectomy, voice, phonology and dysarthria disorders. Both outcome measures are suitable for routine practice. Adaptation of TOM scales for use with head and neck cancer patients may improve sensitivity, validity and therapist compliance. 相似文献
157.
How do stakeholder groups vary in a Delphi technique about primary mental health care and what factors influence their ratings? 下载免费PDF全文
Background: While mental health is a core part of primary care, there are few validated quality measures and little relevant internationally published research. Consensus panel methods are a useful means of developing quality measures where evidence is sparse and/or opinions are diverse. However, little is known about the dynamics of consensus techniques and the factors that influence the judgements and ratings of panels and individual panellists. 相似文献
158.
159.
Rogers R Shuman DW 《The journal of the American Academy of Psychiatry and the Law》2000,28(1):23-8; discussion 29-32
Melton et al. (Melton GB, Petrila J, Poythress NG, Slobogin C: Psychological Evaluations for the Courts (ed 2). New York: Guilford, 1997) recently advocated the use of the Mental State at the Time of the Offense (MSE-Offense) measure not only as a screen for insanity evaluations but also as the sole measure in "obvious" cases of insanity. Given this recommendation for expanding the role of the MSE-Offense, the current authors have evaluated the available data based on its construction and validation. We found fundamental flaws in its development and grave shortcomings in its validation. Based on these limitations, we conclude that the MSE-Offense is unacceptable under the Daubert standard (Daubert v. Merrell Dow Pharmaceuticals, Inc., U.S. 113 S. Ct. 2786 (1993)) for either the screening or determination of criminal responsibility. 相似文献
160.
Clemenza JW Rogers S Magennis P 《Annals of the Royal College of Surgeons of England》2000,82(2):122-127
The microvascular free fibula flap, is currently one of the preferred methods for reconstruction of the oromandibular defect. The patency of the major vessels in the donor limb should be evaluated before the fibula is harvested because the blood supply can be inadequate to safely utilise this flap. The best method of evaluating, pre-operatively, the lower limb vasculature is controversial. Femoral angiography has been considered as the gold standard, however, the current literature advocates less invasive methods of assessment such as magnetic resonance angiography and colour flow Doppler. A postal questionnaire was sent to all members of The British Association of Head and Neck Oncologists asking details of the preferred method of lower limb vascular assessment prior to fibula flap harvest. Of 137 responses, 48 performed free fibula flaps. Of these 48 surgeons, the preferred method for evaluation was palpation of pulses combined with either angiography (40%) or Doppler on the ward (38%). None of this subgroup of surgeons utilised colour flow Doppler as a first line investigation despite this being available to 67% of responders. This survey highlights the diversity in pre-operative assessment amongst surgeons performing fibula flaps for head and neck malignancy. Few relied on clinical examination alone; however, the less invasive methods of vascular imaging were seldom utilised. 相似文献