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261.
The biologic behavior of tumoral cells plays a significant role in the progression of the neoplasia, because 30 to 35% of patients with Stage I squamous cell carcinoma relapse. The present study was designed to determine whether age, pathologic parameters, DNA ploidy, and a cell proliferation index (the area of nucleolar organizer regions, AgNOR), could be used to predict survival in patients who undergo resection for limited squamous cell carcinoma of the lung. For histopathologic analysis, the parameters of histologic grading, pleural involvement, vascular invasion, and residual disease were considered. The cell proliferation index was evaluated by mitotic index, AgNOR quantification, and DNA ploidy by means of digital image analysis. Fifty-two patients (median age, 60 yr +/- 8.6 yr) were staged according to the TNM staging system. Cox univariate analysis showed that stage, residual disease, vascular invasion, histologic grading, DNA ploidy, and AgNOR were significant predictors of survival. Many of the univariate predictors of cancer death, however were eliminated when Cox multivariate models were computed. The variable that exhibited the most robust predictive value for overall survival was AgNOR. We conclude that measurement of cell proliferation might serve as a prognostic marker in squamous cell carcinoma of the lung.  相似文献   
262.
The effects of digoxin on ventricular response during atrial fibrillation (AF) and consequent effects on arrhythmic symptoms have still not been fully explained. This study investigated whether the treatment by digoxin contributes to mid- and long-term stabilization of ventricular cycles in patients with paroxysmal AF. A population of 45 patients with paroxysmal AF underwent 24-hour ECG recordings during each arm of a randomized crossover trial comparing digoxin and placebo. This yielded 30 Holter recordings from 22 patients that contained AF episodes lasting in excess of 2 minutes and with acceptably low Holter noise. Each AF episode was divided into nonoverlapping segments of 30 seconds and the distribution of RR intervals in each segment was compared with the distribution of all other AF segments in the same recording using the Kolmogorov-Smirnov test. The percentage of tests that revealed significant differences at levels of P < or = 0.01, and P < or = 0.001 were sorted according to the time between the segments compared. The comparisons of these results were performed between: (a) all recordings on placebo (n = 16) and all recordings on digoxin (n = 14), and (b) between recordings on placebo and on digoxin in 8 patients in whom paired analysis was possible. Adjacent AF segments (distance 0) differed significantly only in < 30% of both recordings on placebo and on digoxin. However, with increasing the distance between segments, the proportion of the significant differences between RR interval distributions increased more with placebo than with digoxin (P < 10(-300), Chi-square test). Paired data revealed larger differences between placebo and digoxin with increasing distance between segments. Thus in patients with paroxysmal AF, digoxin leads to more reproducible patterns of ventricular cycles that may be better tolerated clinically.  相似文献   
263.
Whether the two earliest cortical somatosensory evoked potentials (SEPs) to tibial nerve stimulation (N37 and P40) are generated by the same dipolar source or, instead, originate from different neuronal populations is still a debated problem. We recorded the early scalp SEPs to tibial nerve stimulation in 10 healthy subjects at rest and during voluntary movement of the stimulated foot. We found that the P40, which reached its highest amplitude on the vertex at rest, changed its topography during movement, since its amplitude was reduced much more in the central than in the parietal traces. These findings suggest that two different components contribute to the centro-parietal positivity at rest: (1) the P37 response, which is parietally distributed and is not modified by movement, and (2) the 'real' P40 SEP, which is focused on the vertex and is reduced in amplitude during voluntary movement. Since, also, the N37 response did not vary its amplitude under interference condition, it is possible that the N37 and P37 potentials are generated by the same dipolar source. Other later components, namely P50 and N50 were significantly reduced in amplitude during foot movement. Lastly, the subcortical P30 far-field remained unchanged and this suggests that the phenomenon of amplitude reduction during movement (i.e. gating) occurs above the cervico-medullary junction.  相似文献   
264.
ML Hawkins  FD Lewis  RS Medeiros 《Canadian Metallurgical Quarterly》1996,41(2):257-63; discussion 263-4
OBJECTIVES: Evaluate independent living, productivity, and social outcomes of patients with serious traumatic brain injury (TBI) after inpatient rehabilitation. METHODS: Fifty-five adults with serious TBI (Abbreviated Injury Scale score > or = 3) were admitted to a Level I trauma center and subsequently transferred to a comprehensive inpatient rehabilitation hospital (Walton Rehabilitation Hospital). Functional Independence Measures were obtained at admission (Adm), discharge (D/C), and at 3- (n = 52) and 1-year (n = 51) follow-up. RESULTS: At 1 year, 90% of the patients were living at home. Eight (16%) required full-time supervision, while 41 (82%) were independent of supervision throughout most of the day. Thirteen (25%) patients had returned to work, eight full time and five with reduced responsibility and fewer hours than before injury. Nineteen shared household duties, while eight (16%) had primary responsibility. Fourteen (27%) patients demonstrated socially inappropriate or disruptive behavior at least weekly. [table: see text] CONCLUSION: Although cognitive skills were diminished for the majority of patients, many achieved a substantial reduction in disability within 18 months after TBI.  相似文献   
265.
PURPOSE: Cytotoxic chemotherapy is frequently required for the more severe manifestations of human immunodeficiency virus (HIV)-related Kaposi's sarcoma. Combinations of bleomycin and vincristine (BV) or BV with the addition of doxorubicin (ABV) are the most commonly used regimens against which new treatments may be compared. We report a multicenter phase III study that compared pegylated liposomal doxorubicin (PLD) to the BV combination. PATIENTS AND METHODS: We conducted a randomized study that compared PLD 20 mg/m2 with a combination of bleomycin 15 IU/m2 and vincristine 2 mg in 241 patients with HIV-related Kaposi's sarcoma. Both regimens were administered by intravenous infusion every 3 weeks for six cycles. RESULTS: A total of 121 patients received PLD and 120 patients the BV combination. The response to PLD was superior to BV: 58.7% versus 23.3% (P < .001). Patients who were randomized to receive BV, however, were more likely to terminate treatment early because of an adverse event (26.7% v 10.7%), and fewer completed the full six cycles of treatment (30.8% v 55.4%). Treatment with BV was associated with a significantly higher incidence of peripheral neuropathy (P < .001), whereas PLD treatment was more commonly associated with neutropenia and delays in receiving treatment (P < or = .001). CONCLUSION: Pegylated liposomal doxorubicin is an effective treatment for HIV-related Kaposi's sarcoma with a higher response rate than the BV combination. It is well tolerated but more myelosuppressive.  相似文献   
266.
OBJECTIVE(S): The reuse of disposable devices is a potential source of significant cost savings to hospitals. Venous and arterial perfusion cannulas under new and reused conditions were selected to identify the clinical, safety, technical, logistic, and economic issues that must be addressed to realize these savings. METHODS: Single- and dual-stage venous and arterial cannulas from two manufacturers were tested when new, after initial clinical use, and after a single clinical use plus up to nine simulated reuses. Reuse was simulated by end-to-end bending, coupling and uncoupling of the connectors, and by two 1-hour soaks in plasma at 4 degrees and 40 degrees C, respectively. Cannulas were decontaminated and then processed by a peracetic acid-based liquid chemical sterilization system after each use/reuse. Sterilization was validated by eliminating Bacillus subtilis spores from the cannulas on each of five consecutive cycles. Cannulas were tested for physical changes, functional integrity, biocompatibility, and in vivo performance in sheep. A cost analysis was also performed. RESULTS: Sterilization was successfully achieved. Mechanical changes were less than 20% on all variables studied and were undetectable by experienced cardiac surgeons in selective evaluation. No clinically important differences were found between new and reused cannulas, even after nine simulated reuses. Reusing cannulas four times would reduce the cost per procedure from $53 to $19 (64%). CONCLUSIONS: Preliminary data suggest that the perfusion cannulas tested can be safely and efficaciously used five times. Limited reuse of these disposable cannulas is technically feasible and cost-effective. Cannula reuse would result in a small incremental savings; however, with more expensive devices and higher-volume sterilization procedures, the savings could be considerably greater. This program provides a model for evaluation of other single-use medical devices for reuse.  相似文献   
267.
BACKGROUND: Outpatient complications leading to hospital readmission after hospitalization for trauma have not been examined. METHODS: A retrospective chart review of all trauma victims admitted to a Level 1 trauma center from January of 1990 to January of 1995 was performed to characterize patients who required readmission after hospitalization for trauma. Risk factors for readmission were determined by stepwise regression analysis. RESULTS: Of 15,463 trauma admissions, 209 patients (1.4%) required readmission, 84% within 30 days, 71% within 14 days. Reasons for readmission included wound (29%), abdominal (29%), pulmonary (18%), and thromboembolic (19%) complications. Fifty of the patients (24%) readmitted with a complication required an operation. Risk factors for readmission included: operation during first hospitalization (p < 0.0001), penetrating injury (p = 0.0001), and advanced age (p = 0.0001). Injury Severity Score, length of hospitalization, and gender were not independent predictors of readmission. CONCLUSIONS: Outpatient complications leading to readmission after hospitalization for trauma are not common; however, many are serious and require operative intervention. Because most complications were identified by the second week after discharge, outpatient follow-up visits should be scheduled within 7 to 14 days. Based on our findings, we recommend protocols be established to ensure follow-up for trauma patients, especially those who have had an operation, were victims of penetrating injury, or those > 65 years of age.  相似文献   
268.
A crucial role for CD1-responsive, MHC class II-unrestricted T cells in the generation of T cell IL-4 responses is suggested by the: 1) requirement for IL-4 to prime in vitro IL-4 responses by naive CD4+ T cells; 2) ability of TCR cross-linking to induce CD1-responsive T cells, but not conventional naive T cells, to produce IL-4; 3) failure of anti-IgD Ab to induce an IL-4-dependent IgE response in beta 2-microglobulin-deficient mice, which lack CD1; and 4) reported ability of MHC class II-deficient mice to make IgE responses to anti-IgD Ab. In contrast, the Ag specificity of cytokine and Ab responses in anti-IgD-injected mice and the normal IgE responses made by anti-IgD-treated CD1-deficient mice are difficult to reconcile with this view. We now find that the failure of beta 2-microglobulin-deficient mice to make an IgE response to anti-IgD Ab is caused by their rapid degradation of anti-IgD; sustained anti-IgD treatment induces them to make relatively normal IL-4 and IgE responses. Furthermore, in our study, MHC class II-deficient mice make little or no IL-4 or IgE responses to anti-IgD Ab and beta 2-microglobulin-deficient mice make large in vivo IL-4 responses to anti-CD3 mAb. Finally, although IL-4 priming of T cells for IL-4 production is Stat6 dependent, Stat6-deficient mice make normal IL-4 responses to anti-IgD. Thus, CD1-responsive T cells and other beta 2-microglobulin-dependent T cells are not required to prime conventional CD4+ T cells to make IL-4 responses to anti-IgD in vivo; in fact, the large IL-4 response made in this system does not require IL-4 priming.  相似文献   
269.
The main objective of the present study was to examine the relationship between regular benzodiazepine (BZD) use and drinking patterns in 55-year-old female residents of Malm?, Sweden. All women born in 1935 (a total of 1223 subjects) were invited to a health screening at the Preventive Medicine Section, Malm? General Hospital; 69% agreed to participate. The screening included an extensive health questionnaire, and the responses to 33 items assessing social background, including immigrant status, use of BZD and analgesics, alcohol consumption (the revised Malm?-MAST), smoking and morbidity were analysed. A psychiatric symptoms scale including five of these items was constructed, yielding a Cronbach's alpha of 0.57. Present use of BZD hypnotics and/or tranquillizers was acknowledged by 6% of the women. BZD use at any time in the past or present was endorsed by 23%. Endorsement of > or = 3 revised Malm?-MAST items, indicating problem drinking, occurred in 3% of the participants; 16% were teetotallers and about 25% were regular weekend drinkers. BZD use was significantly more likely to occur in women with the following characteristics: early retirement, pain symptoms, longstanding use of analgesics, multiple psychiatric symptoms. Drinking patterns in relation to BZD use indicated that regular weekend drinkers were significantly less likely to be current and/or previous BZD users than problem drinkers and teetotallers. Logistic regression analyses indicated that use of BZDs was mainly predicted by endorsement of multiple psychiatric symptoms.  相似文献   
270.
Exon trapping from cosmids mapping to chromosome 19q13.3 yielded 6 exonic sequences that matched the human symplekin gene, which encodes a tight junction-related protein. One exonic sequence identified a 4.0 kb brain cDNA clone, R6E1, which contained 302 bp 5' to the originally reported 3.7 kb symplekin cDNA. A portion of this novel 5' sequence matched an additional trapped exonic sequence which was obtained from the most telomeric cosmid analyzed. The symplekin gene thus lies in a telomeric-to-centromeric direction on 19q13.3. Only three cosmids from a large 19q13.3 contig hybridized with R6E1, thereby assigning the symplekin gene to a 40 kb region immediately telomeric to gene 59 and the DM protein kinase gene. The 5' end of the R6E1 clone has a potential initiation codon with a strong Kozak sequence and Northern blot analysis detected a 4.2 kb signal in most human tissues, indicating that R6E1 may be a complete cDNA sequence. Based on the trapped exonic sequences, twelve exon-intron boundaries were predicted.  相似文献   
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