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81.
I W Brown J P McGoldrick A Robles G W Curella G Gula D N Ross 《The Journal of cardiovascular surgery》1990,31(4):536-540
The management of three patients with left ventricular fibromas is outlined. All were asymptomatic children. Routine chest radiography suggested cardiac masses. M-mode and two-dimensional echocardiography were valuable adjuncts to conventional angiography in assessing these children. Electrocardiographic changes, present in all cases, were shown to regress postoperatively. We stress the importance of these noninvasive aids in the initial investigation and outline our operative methods of reconstruction. 相似文献
82.
Ross D. King Jonathan D. Hirst Michael J. E. Sternberg 《Perspectives in Drug Discovery and Design》1993,1(2):279-290
Summary Neural networks and machine learning are two methods that are increasingly being used to model QSARs. They make few statistical assumptions and are nonlinear and nonparametric. We describe back-propagation from the field of neural networks, and GOLEM from machine learning, and illustrate their learning mechanisms using a simple expository problem. Back-propagation and GOLEM are then compared with multiple linear regression (using the parameters and their squares) on two real drug design problems: the inhibition ofEscherichia coli dihydrofolate reductase (DHFR) by pyrimidines and the inhibition of rat/mouse tumour DHFR by triazines. 相似文献
83.
A. P. Preketes J. R. M. Caplehorn J. King P. R. Clingan W. B. Ross D. L. Morris 《World journal of surgery》1995,19(5):768-771
Thirty-eight patients with unresectable multiple liver metastases from colorectal carcinoma were treated with either hepatic artery chemotherapy (HAC) and cryotherapy (n=27) or cryotherapy alone (n=11). Follow-up survival data were summarized using Cox regression. Allowing for the effect of the pathology of the primary tumor and the preoperative carcinoembryonic antigen (CEA) level, those patients who did not receive HAC after cytoreduction were three times as likely to die as those given HAC (RR 3.3, 95%; CI 1.2–9.3). The estimated median survival of patients treated with cryotherapy alone was 245 days, whereas for those given more than 3 months of HAC plus cytoreduction therapy it was 570 days. It is recommended that all patients who receive cryotherapy for multiple liver metastases from colorectal rectal carcinoma be given subsequent hepatic artery chemotherapy.
Resumen En el presente estudio, 38 pacientes con metástasis hepáticas múltiples y no resecables de carcinoma colo-rectal fueron tratados con quimioterapia administrada en la arteria hepática (HAC) y crioterapia (n=27) o crioterapia sola (n=11). Los datos del seguimiento fueron resumidos según el método de regresión de Cox. Teniendo en cuenta el efecto de la patología del tumor primario y el nivel preoperatorio de antígeno carcino-embrionario, se halló que aquellos pacientes que no recibieron HAC luego de la citorreducción tuvieron una probabilidad de muerte 3 veces mayor que los que recibieron HAC (RR 3.3, 95% CI 1.2 a 9.3). La sobrevida media estimada de los pacientes tratados con crioterapia sola fue de 245 días, en tanto que aquellos que recibieron HAC por tres meses y terapia de citorreducción fue de 570 días. Se recomienda que todos los pacientes que reciben crioterapia para metástasis hepáticas múltiples de carcinoma colo-rectal reciban luego quimioterapia por vía de la arteria hepática.
Résumé Trente-huit patients ayant des métastases hépatiques multiples non reséquables d'origine colorectale ont été traités soit par chimiothérapie par voie artérielle (CVA) associée à la cryothérapie (n=27) soit par cryothérapie seule (n=11). Les survies ont été analysées selon la méthode d'analyse du Modèle de Cox. En tenant compte de l'effet de la pathologie de la tumeur primitive et du niveau préopératoire de l'ACE, les patients n'ayant pas eu de de décéder que ceux qui en ont eu (RR 3.3, 95% IC 12 à 9.3). L'estimation de la survie médiane des patients traités par la cytoréduction seule a été de 245 jours, alors que celle des patients traités par les deux avec une CVA d'au moins trois mois, a été de 570 jours. On recommande que tous les patients ayant des métastases multiples du foie à partir des cancers colorectaux aient une CVA par la suite.相似文献
84.
85.
86.
J. W. Ross 《International urogynecology journal》1997,8(3):146-152
Pelvic organ prolapse remains a difficult problem for pelvic reconstructive surgery. Before new surgical procedures can be
developed a good understanding of pelvic anatomy is necessary. It is widely held that the etiology of pelvic organ prolapse
is secondary to stretch neuropathy following childbirth and chronic cough or constipation. Several transvaginal and transabdominal
procedures have been developed over the years. With the increasing use of laparoscopy, a new variation on existing culdeplasty
techniques has been developed. Following anatomical principles, the apical vault repair reestablishes the pericervical ring
at the vaginal apex. The incorporation of pubocervical fascia, uterosacral-cardinal ligament and the rectovaginal fascia provides
a strong anchor for the vaginal apex. In addition, the repair should help prevent future transverse cystocele, rectocele,
enterocele and apical vault prolapse. Early outcome studies suggest that the apical vault repair should be used routinely
with laparoscopic urethropexy, laparoscopic hysterectomy and the repair of pelvic organ prolapse. Good apical vault support
is considered the cornerstone of pelvic reconstruction. 相似文献
87.
Marilyn Ross Kelly Brewer F Virginia Wright Anne Agur 《Pediatric physical therapy》2007,19(4):288-295
PURPOSE: The purpose of our study was to obtain a clear understanding of the various diagnoses within the closed neural tube defect (NTD) groups included in the large database of clients in our Spina Bifida Clinic and a clear picture of the outcomes for the various NTD groups. METHODS: One hundred and four clients with closed NTD were categorized using a classification system devised by Tortori-Donati et al. Various clinical markers were investigated, including ambulation and the need for orthoses and wheelchairs. RESULTS: Most clients are ambulatory, requiring an orthoses, but not a wheelchair, despite the high incidence of ankle/foot abnormalities. CONCLUSIONS: This classification system has enhanced our knowledge of this group of clients, provided a greater understanding of the varied outcomes of these children and clinical management required. 相似文献
88.
The effects of low-energy 60-Hz environmental electromagnetic fields upon the growth-related enzyme ornithine decarboxylase 总被引:4,自引:0,他引:4
People living in the industrial society of today are unavoidablyexposed to low-energy electromagnetic (EM) radiation. The potentialrisk to human health of such exposure has received much study.In this regard, numerous epidemiological studies have linkedexposure to low-energy EM fields to increased cancer risk. Weinvestigated the ability of low-energy 60-Hz EM fields to alterthe activity of ornithine decarboxylase (ODC) in a number ofestablished cell lines. The activity of ODC, the controllingenzyme in polyamine biosynthesis, has been shown to be elevatedin growing cells or tissues and during the process of tumorpromotion. A 1-h exposure to a 60-Hz EM field of an intensityof 10 mV/cm produced a 5-fold increase in ODC activity in humanlymphoma CEM cells and a 2- to 3-fold increase in mouse myelomacells (P3) relative to the unexposed cultures. Depending uponthe cell type, ODC activity increased during the 1-h exposureperiod and remain ed elevated for several hours after the fieldexposure ended. In another series of experiments, fields ofan intensity as low as 0.1 mV/cm for a 1-h period produced a30% increase in the activity of ODC in Reuber H35 hepatoma cellsgrown in monolayer culture. In the H35 cells, continuous exposureto the 60-Hz EM field (10 mV/cm) for periods of 2 and 3 h resultedin either no increase in ODC activity (2 h) or a decrease inenzyme activity (3 h) compared to the unexposed control cultures.The data is discussed in relation to possible molecular mechanismsof field-cell interaction, the importance of the exposure intervalsaltering cellular ODC activity and the potential ability of60-Hz EM fields to serve as a tumor promoting stimulus. 相似文献
89.
Stimulation of in vivo antibody production and concanavalin-A-induced mouse spleen cell mitogenesis by prolactin 总被引:3,自引:0,他引:3
Regulation of the immune system by neuroendocrine hormones is receiving increased attention. Prolactin, a hormone normally associated with lactation, has been shown recently to reconstitute immunosuppressed hypophysectomized rats. The present studies demonstrate that prolactin administration to normal mice results in a biphasic stimulation of antibody production to sheep red blood cells. While 100 and 200 micrograms bovine prolactin/animal stimulated antibody production, 400 micrograms had no effect. Potentiation of lectin-induced T-cell mitogenesis by prolactin was also biphasic. As the concentration of prolactin increased the incorporation of [3H]thymidine into the cells first increased and then decreased. Decreasing serum prolactin levels with the dopaminergic agonist bromocriptine resulted in a reduction of antibody titers to sheep erythrocytes and a modulation of thymic weight. These data show that prolactin can stimulate the immune system in a biphasic manner and that a reduction in the basal levels of this hormone results in an attenuated immune response. 相似文献
90.
The occupational health nurse can play an important role in supporting employees with CKD and ESRD by recognizing risk factors such as diabetes and hypertension associated with CKD. The occupational health nurse should encourage compliance with treatment regimens that retard or delay progression of kidney disease into the next stage, especially blood pressure and glucose control. When employees are in need of diagnostic testing, the occupational health nurse can describe the testing procedures such as laboratory values, ultrasounds, and biopsies, and explain the five stages of CKD. The occupational health nurse can assist employees in Stage 4 or 5 CKD in deciding on a treatment option modality that best suits their individual lifestyles, after they have seen a nephrologist and kidney patient educator. In addition, the occupational health nurse can guide employees with difficult lifestyle changes and provide support during the adjustment process. The occupational health nurse also can play a key role in facilitating and coordinating those changes with the renal social worker. Together they can explore available resources, such as the NKF, the American Association of Kidney Patients, and kidneydirections.com. See the Sidebar on pages 295 to 296 for other available resources. Kidney disease can be a devastating diagnosis. Support and education are key to a successful lifestyle transition. Employees who have CKD and work with an occupational health nurse who is informed about their disease and its stages of progression can benefit from educational processes that create informed choices to delay or retard the progression of their renal disease. 相似文献