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81.
Ronald S. Sutherland Barry A. Kogan Laurence S. Baskin Robert A. Mevorach 《The Journal of urology》1996,156(6):2041-2043
Purpose
We compared a recently developed hydrophilic catheter to the standard polyethylene catheter in regard to hematuria, infection and patient satisfaction.Materials and Methods
A hydrophilic LoFric* or standard Mentor† catheter was assigned at random to 17 and 16 boys, respectively, who were skilled in intermittent self-catheterization. They were evaluated by weekly urinalysis and a questionnaire.Results
Significantly fewer episodes of microscopic hematuria occurred in the LoFric than Mentor catheter group (9 episodes in 6 subjects versus 19 episodes in 11, p less than 0.05). There were also fewer episodes of bacteriuria in the LoFric group but the difference was not statistically significant. Mean scores plus or minus standard deviation on a visual analogue scale with 0 equal to most and 10 equal to least favorable were LoFric 3.3 plus/minus 2.8 versus Mentor 4.9 plus/minus 2.7 for catheter convenience and 2.7 plus/minus 2.4 versus 4.2 plus/minus 2.6 for insertion comfort, significantly favoring the LoFric group (p less than 0.05 for both). Of the 16 LoFric subjects 13 preferred to continue its use, particularly those with a history of urethral trauma or sphincteric spasm.Conclusions
In boys the LoFric catheter appears to cause less trauma. Although it is not reusable and is more expensive than the standard catheter, satisfaction is higher with the LoFric device and for select patients it has significant advantages. 相似文献82.
83.
MCF-7 human mammary carcinoma cells were inoculated into 150-sq cm flasks at 3 X 10(5) cells/flask, and after a lag period of about 48 hr, these cells grew exponentially for 5 days with a mean population doubling time of about 24 hr. During exponential growth, 80 to 90% of cells were in the "rapidly cycling" pool, the clonogenic fraction was 50 to 60%, and the mean percentage of cells in the G0-G1, S, and G2 + M phases of the cell cycle was 48.9 +/- 0.6% (S.E.), 39.4 +/- 0.6%, and 11.6 +/- 0.3%, respectively. These parameters changed rapidly between Days 7 and 13 when plateau phase was reached. Between Days 13 and 18, 74.8 +/- 0.7% of cells were in G0-G1, 15.3 +/- 0.4% were in S, and 9.8 +/- 0.6% were in G2 + M phase. Only about 30% of these cells were cycling rapidly, and the clonogenic fraction had fallen to less than 10%. Tamoxifen induced a dose-dependent decrease in the growth rate of exponentially growing cells, which was accompanied by a dose-dependent increase in percentage of G0-G1-phase cells, and a decline in percentage of S-phase cells. At doses greater than or equal to 10 microM, a 24-hr pulse of tamoxifen was cytotoxic to exponentially growing cells. Plateau-phase cells were less sensitive to these effects of tamoxifen. In an attempt to define the kinetic basis of the G0-G1 accumulation induced by tamoxifen, asynchronous MCF-7 cells were pretreated for 42 hr with various doses of tamoxifen, and the rate of efflux of cells from the G0-G1 phase of the cell cycle was assessed by blocking their reentry into G1 with ICRF 159. Following treatment of control cultures with ICRF 159, two populations of cells were distinguished by their rates of efflux from G0-G1 phase. The majority of cells left G0-G1 rapidly with a mean t1/2 of 2.3 hr ("rapidly cycling" cells). However, about 18% of cells had a much slower rate of exit with a mean t1/2 of about 30 hr ("slowly cycling" cells). Pretreatment with tamoxifen resulted in a dose-dependent decrease in the proportion of rapidly cycling cells and an increase in the proportion of cells with slow G1 transit times. Although this appeared to be the predominant effect, tamoxifen also decreased the rate at which the slowly cycling cells traversed G1. Simultaneous treatment with estradiol returned these parameters to control values at doses of tamoxifen less than or equal to 5 microM, partially reversed the effect of 7.5 microM tamoxifen, but was without effect on the arrest of cell cycle progression induced by 10 microM tamoxifen. It is concluded that cells accumulate in G0-G1 following tamoxifen treatment due to an increase in the proportion of slowly cycling cells at the expense of a population of rapidly cycling cells, which appear to be relatively uninfluenced by the drug. 相似文献
84.
G Farmer D R Hamilton-Nicol H W Sutherland I S Ross G Russell D W Pearson 《American journal of obstetrics and gynecology》1992,167(3):772-777
OBJECTIVE: We characterized insulin secretion and glucose disposal in a large unselected group of women, encompassing the full spectrum of glucose tolerance in pregnancy, and related the findings to maternal obesity. STUDY DESIGN: Intravenous glucose tolerance and first-phase insulin response were measured at about 32 weeks' gestation in 690 unselected pregnancies. The women were designated as "lean," "normal," or "obese" on weight-for-height criteria. RESULTS: The distribution of insulin response was bimodal, but there was no corresponding dichotomy in maternal glucose disposal rate. Insulin response was greatest and glucose disposal rate slowest in obese women. In general, "poor" glucose tolerance was associated with relatively low insulin output. It was not possible to identify any cluster of women, obese or otherwise, in whom poor glucose tolerance was specifically associated with an unusually high insulin response. CONCLUSION: The data indicate that the distribution of glucose tolerance in pregnancy is a continuum. Glucose intolerance represents one end of that spectrum and is attributable to insufficient insulin secretion. This relative insufficiency is most frequent with maternal obesity. 相似文献
85.
Effect of nonmedical factors on family physicians' decisions about referral for consultation. 总被引:4,自引:1,他引:3
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G R Langley A M MacLellan H J Sutherland J E Till 《Canadian Medical Association journal》1992,147(5):659-666
OBJECTIVES: To identify nonmedical factors perceived by family physicians (FPs) and consultants as important influences on decisions about referral for consultation, to determine the relative frequency with which such factors are cited and to identify those factors ranked as most important by the FPs and consultants. DESIGN: Survey with semistructured interview between July 1989 and April 1990. PARTICIPANTS: A total of 41 FPs and 20 consultants who were practising or had practised previously in Nova Scotia. INTERVENTIONS: The questionnaire comprised 10 questions: 4 were nondirective "probes" designed to elicit responses without suggesting possible answers, 2 asked the participants to rank such responses in order of importance, and 4 were "prompts" that asked for comments about a list of factors based on a review of the literature. RESULTS: A total of 4845 discrete items were mentioned as being capable of influencing FPs' decisions about referral for consultation. Aggregation of related items resulted in a list of 35 nonmedical factors, of which 11 were identified by at least half the respondents and 14 by less than half but more than 10. These 25 factors fell into three categories: patient and family factors (e.g., patient's wishes), FP and consultant factors (e.g., FP's capabilities), and other influences (e.g., style of practice). On the basis of both frequency of identification and priority scores "patient's wishes" emerged as the most important factor. Two medical factors that were consistently cited--type of problem and age of patient--were thought to interact with the other factors. CONCLUSION: Certain nonmedical considerations may substantially affect physicians' referral practices. 相似文献
86.
Sensory nerve pathology in amyotrophic lateral sclerosis 总被引:2,自引:0,他引:2
T. Heads M. Pollock A. Robertson W. H. F. Sutherland S. Allpress 《Acta neuropathologica》1991,82(4):316-320
Summary A detailed morphometric study was performed on sural nerve biopsies to determine the consistency of sensory nerve pathology in amyotrophic lateral slcerosis (ALS) and to seek a correlation between the severity of peripheral nerve pathology and disease duration. Nerve biopsies from patients with ALS consistently showed evidence of early axonal atrophy, increased remylination and a shift in the diameter distributions curve towards smaller fiber diameters. Importantly, the severity of sensory nerve pathlogy in ALS patients correlated with disease duration. The peripheral nerve sodium pump concentration of patients was not reduced. It is concluded that an ingravescent dorsal root ganglion neuronopathy is seen in the incipient stages of ALS, preferentially affecting the largest neurons and resulting in turn in progressive axonal atrophy, secondary demyelination-remyelination and finally in nerve fiber degeneration. Etiologically, a parallel involvement of motor and sensory neurons suggests a more widespread metabolic disturbance in ALS than simply sick motor neurons.Supported by a grant from the New Zealand Neurological Foundation 相似文献
87.
DL-ethionine Treatment of Adult Pancreatic Donors: Amelioration of Diabetes in Multiple Recipients with Tissue From a Single Donor
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William D. Payne David E. R. Sutherland Arthur J. Matas Phyllis Gorecki John S. Najarian 《Annals of surgery》1979,189(2):248-256
Transplantation of adult rat pancreatic islet tissue as a free graft requires the separation of islet from exocrine tissue to avoid host injury or graft destruction by digestive enzymes. The poor yield from islet isolation techniques currently necessitates the use of multiple donors to ameliorate diabetes in a single recipient. DL-ethionine (DLE) is an agent selectively toxic to the exocrine pancreas. We examined the effect of DLE administration on pancreatic digestive enzyme content and islet mass in adult Lewis rats and the ability of such pancreatic tissue dispersed by collagenase digestion without specific islet isolation to ameliorate diabetes when transplanted to the portal vein of syngeneic rats with streptozotocin induced diabetes. Rats fed normal chow supplemented with 0.5% DLE for 14-20 days showed a logarithmic loss of pancreatic mass. Total pancreatic amylase content declined to 0.3 + 0.1 mg, less than 3% of control values (14.3 +/- 1.0 mg). Total insulin content in DLE treated rats was 87 +/- 8 microg, not significantly different from control rats (101 +/- 7 microg). Histological examination confirmed the selective atrophy of exocrine tissue in DLE treated rats. Fresh pancreatic tissue prepared from a single DLE treated donor ameliorated diabetes 75% of the time when transplanted to one or two recipients and 65% of the time when divided between three of four recipients. Tissue prepared from a single DLE treated donor and stored for 24-48 hours ameliorated diabetes 91% of the time when divided between one or two recipients. Only four of 31 diabetic rats transplanted with fresh pancreatic tissue from untreated adult donors became normoglycemic. Pretreatment of adult rats with DLE induces selective exocrine atrophy, permits dispersed pancreatic tissue from a single donor to ameliorate experimental diabetes in up to four recipients, and allows tissue to be preserved by culture for up to 48 hours without specific islet isolation. 相似文献
88.
J. V. Forrester G. R. Sutherland M. McDonald 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1977,204(2):101-112
Summary Vitreous haemorrhages were induced in rabbits and the echographic appearances on A and B scan were correlated with the gross and histologic appearances over a period of twenty weeks. In all cases, visible vitreous opacities produced distinct echo patterns. As the haemorrhages cleared, the echo amplitudes became progressively weaker. Several patterns of vitreous membranes on B scan were also observed. Pathological examination revealed that such membranes were composed of red cells, macrophages and condensed vitreous collagen. It is suggested that haematogenous vitreous membranes of this type are readily diagnosed by combined A- and B-scan ultrasonic examination, and are probably amenable to surgery. 相似文献
89.
BACKGROUND: The transplant literature has not shown cytomegalovirus (CMV) disease to be a significant risk factor for posttransplant cardiac complications. A large number of nontransplant studies have, however, reported an association between coronary heart disease (CHD) and CMV disease. Pathology studies have demonstrated a high incidence of CMV in atheromatous plaques from the coronary circulation. METHODS: We performed multivariate analysis to determine if posttransplant CMV disease was a significant risk factor for cardiac complications in kidney transplant recipients. We also performed univariate analysis to determine which cardiac complications were more common in the recipients with CMV disease. RESULTS: Between January 1, 1984 and June 30, 1997, 1859 adults underwent kidney transplants at our institution. Of these, 377 developed one of the following cardiac complications posttransplant: myocardial infarction, angina, arrhythmia, congestive heart failure, and angiographic vessel occlusion. By multivariate analysis, significant risk factors for one of the above cardiac complications were recipient age >50 years [odds ratio (OR)=2.5, P=0.0001], diabetes (OR=1.99, P=0.0001), a history of cardiac disease pretransplant (OR= 1.34, P=0.04), and CMV disease (OR=1.5, P=0.01). Univariate analysis demonstrated that recipients with CMV disease had a higher overall incidence of cardiac complications. Arrhythmias, congestive heart failure, and vessel occlusion were more common in those with CMV disease. The incidence of myocardial infarction, angina, and cardiac arrest did not differ between the two groups (recipients with versus without CMV disease). CONCLUSIONS: CMV disease is associated with an increased risk of cardiac complications in kidney transplant recipients. In our series, angiographic vessel occlusion was more common in recipients with CMV disease. This interesting finding may support the theory that CMV plays some role in the pathogenesis of CHD. 相似文献
90.
Living unrelated donors in kidney transplants: better long-term results than with non-HLA-identical living related donors? 总被引:3,自引:0,他引:3
BACKGROUND: Given the severe organ shortage and the documented superior results obtained with living (vs. cadaver) donor kidney transplants, we have adopted a very aggressive policy for the use of living donors. Currently, we make thorough attempts to locate a living related donor (LRD) or a living unrelated donor (LURD) before proceeding with a cadaver transplant. METHODS: We compared the results of our LURD versus LRD transplants to determine any significant difference in outcome. RESULTS: Between 1/1/84 and 6/30/98, we performed 711 adult kidney transplants with non-HLA-identical living donors. Of these, 595 procedures used LRDs and 116 used LURDs. Immunosuppression for both groups was cyclosporine-based, although LURD recipients received 5-7 days of induction therapy (antilymphocyte globulin or antithymocyte globulin), whereas LRD recipients did not. LURD recipients tended to be older, to have inferior HLA matching, and to have older donors than did the LRD recipients (all factors potentially associated with decreased graft survival). Short-term results, including initial graft function and incidence of acute rejection, were similar in the two groups. LURD recipients had a slightly higher incidence of cytomegalovirus disease (P=NS). We found no difference in patient and graft survival rates. However, the incidence of biopsy-proven chronic rejection was significantly lower among LURD recipients (16.7% for LRD recipients and 10.0% for LURD recipients at 5 years posttransplant; P=0.05). LRD recipients also had a greater incidence of late (>6 months posttransplant) acute rejection episodes than did the LURD recipients (8.6% vs. 2.6%, P=0.04). The exact reason for these findings is unknown. CONCLUSION: Although LURD recipients have poorer HLA matching and older donors, their patient and graft survival rates are equivalent to those of non-HLA-identical LRD recipients. The incidence of biopsy-proven chronic rejection is lower in LURD transplants. Given this finding and the superior results of living donor (vs. cadaver) transplants, a thorough search should be made for a living donor-LRD or LURD-before proceeding with a cadaver transplant. 相似文献