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971.
Phillips I 《The Journal of hospital infection》1999,43(3):173-178
972.
Phillips VL Temkin A Vesmarovich S Burns R Idleman L 《International journal of technology assessment in health care》1999,15(4):749-755
OBJECTIVE: To determine which of three approaches to care produces the lowest incidence of pressure ulcers, promotes the most effective care of sores that develop, and leads to the fewest hospitalizations in newly injured patients with spinal cord injury after discharge. METHODS: Spinal cord injury patients (n = 12) were recruited for a telehealth intervention after initial injury, and matched cases were recruited for telephone counseling and standard care groups. Patients were monitored for 6-8 months after discharge. RESULTS: The video group had the greatest number of reported and identified pressure ulcers. Differences in health care utilization between the video and telephone telehealth groups were small. The standard care group reported the lowest number of pressure ulcers and lowest frequency of health care utilization. Substantial differences existed in employment rates before and after injury. The video group had the lowest pre-injury rate of employment and the highest post-injury rate of employment. CONCLUSIONS: Tracking pressure ulcer incidence, particularly stage I sores, is difficult. Self-report is likely to lead to substantial underreporting. Similarly, self-report on health care utilization over extended periods may lead to undercounting of encounters. Telehealth interventions appear to improve ulcer tracking and management of all ulcer occurrences. Video interventions may affect outcomes, such as employment rates, which are not conventionally measured. 相似文献
973.
Speer C Pearlman J Phillips PH Cooney M Repka MX 《American journal of ophthalmology》1999,127(2):236-237
PURPOSE: To describe three children with acute fourth cranial nerve palsy secondary to pseudotumor cerebri. METHODS: We reviewed the medical records of children younger than 18 years who were diagnosed with pseudotumor cerebri between 1977 and 1997. Pseudotumor cerebri was defined by normal neuro-imaging, elevated intracranial pressure measured by lumbar puncture, and normal cerebrospinal fluid composition. RESULTS: Three children with pseudotumor cerebri presented with vertical diplopia and clinical signs of fourth cranial nerve palsy including a hypertropia of the affected eye, which increased with adduction and ipsilateral head tilt. The fourth cranial nerve palsy resolved after reduction of the intracranial pressure in all three children. CONCLUSIONS: Fourth cranial nerve palsy may occur in children with pseudotumor cerebri and may be a nonspecific sign of elevated intracranial pressure. 相似文献
974.
D H Char A I Irvine M D Posner J Quivey T L Phillips S Kroll 《American journal of ophthalmology》1999,127(5):574-578
PURPOSE: To assess external beam radiation efficacy for subfoveal neovascularization associated with age-related macular degeneration. METHODS: All patients were evaluated in the same institution. In this prospective trial, 27 eyes (27 patients) with subfoveal neovascularization associated with age-related macular degeneration were randomized to either single fraction radiation (750 centigray) or observation. Endpoints were assessed by fluorescein angiography and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity. Examiners were masked to patient treatment status. Parametric and nonparametric statistical analyses were performed. RESULTS: Twenty-seven patients were entered into the trial with a mean age of 76 years (range, 64 to 89) and a mean follow-up of 17 months (range, 7 to 32). The visual acuity loss was slightly less in the irradiated group, a finding of borderline significance (P < .046). There was no significant difference in fluorescein angiographic evidence of subretinal neovascular membrane change in the control group vs the irradiated group. CONCLUSIONS: External beam radiation, at this dose and fractionation, did not appear harmful. There was slightly less visual loss in irradiated eyes. No difference in fluorescein angiographic characteristics of subfoveal neovascularization size or progression in eyes with age-related macular degeneration was noted. 相似文献
975.
R M Phillips 《Biochemical pharmacology》1999,58(2):303-310
The tumour blood flow inhibitors 5,6-dimethylxanthenone-4-acetic acid (DMXAA) and flavone-8-acetic acid (FAA) have been shown to potentiate the antitumour activity of several bioreductive drugs in vivo. Whilst the induction of hypoxia as a result of blood flow inhibition is presumed to be responsible for enhancing the activity of bioreductive drugs, no studies have examined potential interactions between DMXAA or FAA and enzymes involved in bioreductive drug activation. Both FAA and DMXAA are competitive inhibitors of the enzyme DT-diaphorase (NAD(P)H:Quinone oxidoreductase EC 1.6.99.2) with respect to NADH, with Ki values of 75 and 20 microM, respectively. Cytochromes P450 reductase and b5 reductase activities are not significantly inhibited by FAA, whereas DMXAA partially inhibits cytochrome b5 reductase activity. The cytotoxicity of the indoloquinone EO9 (3-hydroxymethyl-5-aziridinyl-1-methyl-2-[1H-indole-4,7-dione] prop-beta-en-alpha-ol) against DLD-1 (IC50 = 0.32+/-0.08 microM) was significantly reduced when combinations of EO9 and FAA (IC50 = 12.26+/-5.43 microM) or DMXAA (IC50 > 40 microM) were used. In the case of menadione (which is detoxified by DT-diaphorase), combinations of menadione with FAA or DMXAA were more toxic (IC50 = 7.46+/-2.22 and 9.46+/-1.70 microM, respectively) than menadione alone (IC50 = 22.02+/-1.59 microM). Neither DMXAA nor FAA potentiated the activity of tirapazamine in vitro. These results suggest that the use of DMXAA and FAA to potentiate the activity of bioreductive drugs where DT-diaphorase plays a central role in either activation or detoxification may be inappropriate. The fact that FAA in particular does not inhibit other key enzymes involved in bioreductive activation suggests that it may be useful in terms of identifying DT-diaphorase-activated prodrugs. 相似文献
976.
G Phillips D D Davey K A Eagen S K Koovakkat A Liang H P Ng M Pinkerton L Trinh M Whitlow A M Beatty M M Morrissey 《Journal of medicinal chemistry》1999,42(10):1749-1756
A novel series of 2,6-diphenoxypyridines has been designed to inhibit factor Xa, a serine protease strategically located in the coagulation cascade. The evolution from the photochemically unstable bisamidine (Z,Z)-BABCH to potent bisamidine compounds with a pyridine heterocycle as the core scaffold has been achieved. The most potent compound in the series, 6h, has a Ki for human factor Xa of 12 nM. The selectivity of 6h against bovine trypsin and human thrombin was greater than 90- and 1000-fold, respectively. Two proposed modes of binding of 6h to factor Xa are made based on the crystal structures of 6h by itself and of 6h bound to bovine trypsin. 相似文献
977.
We have shown that prior repeated exposure to d-amphetamine facilitates appetitive Pavlovian conditioning. However, animals sensitised in this manner also show elevated
levels of stimulated activity. To investigate whether enhanced conditioning was dependent upon increased activity, a conditioned
inhibition task was employed in the present study. Rats received d-amphetamine (2 mg/kg, IP) or vehicle once per day for 7 days. After a 7-day drug-free period, an activity assay confirmed
that repeated d-amphetamine treatment markedly elevated the locomotor response to a subsequent challenge with 0.5 mg/kg d-amphetamine. Conditioning began 6 days later. In phase 1, stimulus A+ (light or tone) immediately preceded sucrose availability
(excitatory conditioning). In phase 2, sucrose again was presented after A+ alone, but not after presentation of a compound
of A+ with a second stimulus (AB−). Sensitisation enhanced the acquisition of conditioned approach behaviour to the excitatory
stimulus A+ in phase 1. Furthermore, acquisition of conditioned inhibition to the stimulus compound, AB−, was also facilitated.
Thus, sensitised rats showed reduced levels of responding to the stimulus compound far sooner than controls. Finally, a retardation
test was carried out in stage 3, in which the inhibitory stimulus B- was paired alone with sucrose reward. Sensitised rats
initially showed retarded acquisition of excitatory conditioned responding relative to controls, suggesting that B possessed
stronger inhibitory associations in these animals. However, sensitised animals again exhibited higher levels of responding
in later sessions, consistent with the enhanced excitatory conditioning shown in phase 1. These findings suggest that prior
repeated d-amphetamine enhanced the acquisition of inhibitory and excitatory Pavlovian associations; a propensity not readily attributable
to stimulated locomotor hyperactivity.
Received: 29 December 1997/Final version: 21 July 1998 相似文献
978.
Interference by plastics additives in the HPLC determination of microcystin-LR and -YR. 总被引:6,自引:0,他引:6
Plastics devices used for the field collection of water samples may contain plastics additives which will interfere with the HPLC determination of the cyanobacterial toxins microcystins. The presence of the additives resorcinol monobenzoate or 2,4-dihydroxybenzophenone can interfere with the determination of microcystin-LR. The presence of bisphenol A in plastics can interfere with the determination of microcystin-YR. 相似文献
979.
Feran Agachan Jae Sik Joo Eric G. Weiss Steven D. Wexner 《Diseases of the colon and rectum》1996,39(10):S14-S19
PURPOSE: The aim of this study was to assess various intraoperative and postoperative complications associated with laparoscopic colorectal surgery. Specifically, the impact of surgical experience and procedure type on complications was analyzed. METHODS: All patients who underwent laparoscopic surgery were analyzed by age, sex, surgical indications, procedure performed, procedure length, intraoperative and postoperative complications, incidence and causes for conversion, duration of postoperative ileus, and length of hospital stay. Patients were classified for type of procedure and chronologically into four consecutive groups. Procedures were also categorized into four different groups: GI, total abdominal colectomies; GII, segmental resections; GIII, diverting procedures; GIV, others (abdominoperineal resection, Hartmann's creation or closure, anterior resection, and rectopexy). RESULTS: Between August 1991 and October 1995, 167 patients of a mean age of 49.6 (15–88) years underwent laparoscopic colorectal procedures. All procedures were electively performed. Common indications for surgery included inflammatory disease in 70 (42 percent), neoplasia in 56 (33 percent), functional bowel disorders in 30 (18 percent), and other forms of colorectal disorders in 11 (7 percent) patients. The most significant variable affecting intraoperative laparoscopic complication rate was surgical experience measured as the time interval during which surgery was performed (P=0.02). Total complication rate decreased from 29 percent during the first period to 11 percent by the second period (P<0.04) and 7 percent during the third period (P<0.005). Thus, the learning curve appeared to have required more than 50 cases to achieve. Moreover, even after performance of 94 (1991–1993) procedures in GI and GIV, these procedures were associated with higher complication rates than were those procedures in GII and GIII (P=0.04). CONCLUSION: Surgical experience and case selection are the most critical variables by which the surgeon can decrease the intraoperative laparoscopic complication rate. 相似文献
980.
Morris E. FranklinJr. Daniel Rosenthal Daniel Abrego-Medina James P. Dorman Jeffrey L. Glass Richard Norem Antonio Diaz 《Diseases of the colon and rectum》1996,39(10):S35-S46
Laparoscopy for colonic diseases began in 1990 and has established a role in benign disease. Early observations and experiences demonstrated feasibility of laparoscopic surgery for a variety of colonic disease processes, but the applicability to colonic carcinoma was unclear. METHODS: In 1990, we began a comparative study of open (OCR)vs.laparoscopic (LCR) approach to colon cancer. The study progressed 65 months, with 224 patients in OCR group and 191 patients in LCR group. Parameters studied are stage, location, length of specimen, number of lymph nodes resected, margins, postoperative course, wound complications, recurrence rates, and immediate and long-term survival. OCR were standardized by one group, and LCR were standardized by a second group. All patients undergoing LCR were given freedom to choose either OCR or LCR, and informed consent was obtained. RESULTS: Equal or greater lymph node retrieval, resections, and distal margins were evident with LCR. Benefits with LCR were shown with shorter hospitalization (5.7vs.9.7 days), less blood loss, less wound problems (1vs.14), and quicker return of bowel function. Survival, recurrence, and death rates were essentially the same. There were no trocar implants in the LCR group. CONCLUSION: After five years, this study shows that laparoscopy does no harm to the patient, offers comparable oncologic resections, and seems to be patient-friendly, with less pain, quicker return of bowel functions, shortened hospitalization, and quicker return to full activity. 相似文献