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G. J. Wiener MD T. M. Morgan PhD J. B. Copper PA W.C. Wu MB BS D. O. Castell MD J. W. Sinclair PA Dr. J. E. Richter MD 《Digestive diseases and sciences》1988,33(9):1127-1133
If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH<4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH<4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean ±2sd of the relative differences between the two test results for all 53 subjects. Total percent time with pH<4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.Supported, in part, by Public Health Services Grant AM 34200-01A1 from NIADDIK. 相似文献
44.
Development of a reconstructed human skin model for angiogenesis 总被引:4,自引:0,他引:4
Parbinder S. Sahota MB ChB MRCS ; J. Lance Burn PhD ; Martin Heaton FRCS MD ; Eric Freedlander FRCS MD ; Simon K. Suvarna FRCPath ; Nicola J. Brown PhD ; Shelia Mac Neil PhD 《Wound repair and regeneration》2003,11(4):275-284
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells. 相似文献
45.
A E O'Hare MD FRCP G N Dutton FRCS FRCOphth D Green MB ChB MRCP Rosemary Coull 《Developmental medicine and child neurology》1998,40(6):417-420
The progress of cognitive visual dysfunction over an 8-year period of a child who sustained bilateral occipital-lobe infarctions at the age of 21/2 years is described. She survived with normal intelligence and went on to attend mainstream school. She manifested many features of cognitive visual impairment and, in particular, developed a form of pure alexia without agraphia. She achieved some letter-by-letter reading but no sight vocabulary development, including to her own name. She learned to write imaginatively employing phonetically true spelling but cannot read what she has written. Her progress and the difficulties encountered during the management of her condition are discussed in this first case report of the evolution of pure alexia without agraphia in childhood. The features of this syndrome in the developing child who has never developed the capacity to read are contrasted with that seen in affected adults. 相似文献
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B. P. Kavanagh MB BSc Dr A. N. Sandler MB MSc K. E. Turner MD V. Wick BScN S. Lawson 《Journal of clinical monitoring and computing》1992,8(3):226-230
This study was designed to assess the accuracy of end-tidalPco 2 and transcutaneousPco 2 as measurements of arterialPco 2 in extubated, spontaneously breathing patients recovering from general anesthesia. In 30 patients, measurement of arterial transcutaneous, and end-tidalPco 2 were taken simultaneously with body temperature approximately every 15 minutes over a 2-hour period. ArterialPco 2 values were corrected for body temperature. Values for Paco 2 were compared with those forPetCO2 and Psco 2 by linear regression analysis and by calculation of bias ± precision. Thirty-six percent of the capnogram tracings obtained did not develop a plateau phase. We found poor correlation between end-tidal and arterialPco 2 regardless of the shape of the capnogram tracing, as well as poor correlation between transcutaneous and arterialPco 2. Although the measurements of bias and precision of noninvasivePco 2 monitors in this population are comparable to studies in other populations, we advise caution in relying on the routine use ofPetCO2 or Psco 2 for the noninvasive assessment of respiratory depression in extubated, spontaneously breathing patients recovering from general anesthesia. 相似文献
48.
In some parts of the United Kingdom (UK), family doctors (or "general practitioners" as they are called in the UK) are routinely called upon by the emergency medical services (EMS) system to attend road accidents. The doctors are volunteers and travel to the scene of the accident in their own cars. Members of one such general practitioner accident service operating in Mid-Anglia complete an accident report form after attending each incident. In 1983, the Mid-Anglia General Practitioner Accident Service (MAGPAS) received 1,715 calls for medical assistance, and in 95% of these a doctor was sent immediately. Of these calls, 57% were passed to the doctor within one minute of the receipt of the call in the MAGPAS control room, and 78% were relayed within two minutes. This rapid call-out, combined with the close proximity of the local doctor to the accident site, resulted in the doctors arriving ahead of the ambulance in 42% of the calls. A total of 54 patients with airway obstruction were treated by the doctors prior to the arrival of the ambulance. Ninety-nine patients required immediate intravenous fluid replacement in the pre-hospital phase of their medical care. This report suggests that general practitioners in rural areas can play a vital role in the early management of trauma patients, especially in the absence of ambulance personnel trained in advanced life support skills. 相似文献
49.
Eun L. Langman MD Cherie M. Kuzmiak DO Rachel Brader MD Samantha M. Thomas MB Sophia L. Alexander Sheila S. Lee MD Sheryl G. Jordan MD 《The breast journal》2021,27(8):657-663
The purpose of this study was to characterize presenting imaging findings in women younger than 40 diagnosed with invasive breast cancer in the context of pathology and clinical course. Retrospective chart and imaging reviews were performed in patients under 40 diagnosed with breast cancer between July 1, 2004, and December 31, 2013. Patient demographic, imaging, pathology, and clinical data were collected. Overall and recurrence-free survival were estimated using the Kaplan-Meier method. Univariate Cox proportional hazards models were performed to identify factors associated with recurrence-free survival. Our study cohort consisted of 110 patients with invasive mammary carcinoma. One hundred one (91.8%) presented with a palpable mass. The mean size of all lesions on imaging was 3.5 cm ± 2.9 cm. Malignant calcifications were present in 54 (49.1%) cases. Imaging demonstrated multifocal or multicentric disease in 45 (40.9%) cases. Seventy four (67.3%) cancers were high grade. Luminal genomic subtypes were the most common (n = 61, 55.5%). At presentation, 4 (3.6%) patients had bilateral malignancy and 8 (7.3%) patients had distant metastatic disease. Ninety seven (88.2%) underwent neoadjuvant chemotherapy and 67 (60.9%) underwent radiation therapy. Seventy five (68.2%) of the patients underwent mastectomy. The restricted mean time to recurrence was 9.01 years (standard error 3.162 months). ER positivity was associated with compromised recurrence-free survival. The overall survival rate was 0.962 at 10 years. Young patients diagnosed with breast cancer typically present with advanced breast imaging findings and undergo aggressive treatment. Recurrence often occurs >5 years from diagnosis, and ER positive subtypes are at increased risk for recurrence. 相似文献
50.
Twenty of 26 (77%) consecutive patients undergoing ileogastrostomy, performed by the same surgeon (IGMC) between February
1989 and May 1992, responded to a mailed quality of life survey. Average present weight was reported as 50.9 kg less than
a mean preoperative weight of 139.7 kg. Mean time of follow-up was 24.75 months. When comparing perceptions before and after
surgery, several quality of life improvements were noted in the areas of vocation, relationships, emotional well-being and
physical well-being. Post-surgery, jobs were rated more satisfying, eating habits improved, self-image and self-confidence
increased and body disparagement declined. Satisfaction with sexual relations increased, as did frequency. In general, relations
with partners, co-workers and friends seemed to improve. Exercise also increased significantly. In contrast, foul flatus,
bloating, and bowel movements regularly hampered activities or caused embarassment when in public. Despite these physical
side-effects, we observed that a large majority of persons undergoing ileogastrostomy noted significant improvements in quality
of life. 相似文献