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61.
This study was undertaken to identify preoperative and intraoperative factors that correlate with the need for postoperative vasoactive medication (VM) use. Clinical data from 100 carotid endarterectomies (CEAs) performed in 93 patients were reviewed. Baseline comorbidities, medications, perioperative physiologic data, and operative technique were evaluated for their association with the need for postoperative VM use. Statistical analysis included univariate and multivariate logistic regression with odds ratios (ORs) and 95% confidence intervals (CIs) reported. Hemodynamic instability affected 43 patients, of whom 32 had VM started in the postanesthesia care unit (PACU). No patient who was hemodynamically stable in the PACU later required VM. The only preoperative factor associated with a need for postoperative VM was a prior stroke (OR 4.5; 95% CI 1.2-16.2; p = .02). Intraoperative factors associated with the need for postoperative VM included use of a shunt (OR 5.1; 95% CI 1.2-22.2; p = .03) and a peak intraoperative systolic blood pressure greater than 200 mm Hg (OR 5.1; 95% CI 1.2-22.2; p = .03). The number and type of preoperative blood pressure medications, preoperative hypertension, comorbidities, symptomatic presentation, and intraoperative use of VM did not correlate with postoperative VM use. There were two strokes and no deaths. Patients undergoing CEA who are hemodynamically stable in the PACU appear to be reasonable candidates for same-day discharge and warrant further prospective study.  相似文献   
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Natural preparations for replenishing of hyaluronic acid of zoogenous origin used till now, are characterized with quit low biocompatibility and also too short effect of their action. Recently worked out synthetic polyvinylpyrrolidone preparation PVP, contains modification constituting internally netting of microgels to improve polymer bioresistance. The introduce modification can, however influence PVP biocompatibility after deposition into tissues of the living organism. The aim of research was evaluation of the local reaction of muscular tissue after PVP infection. The results of research concerned a control group where normal saline was used for infections. The research was carried out on 18 Wistar rats and included macroscopic and histologic observations made in the 3rd, 5th, 7th, 14th and 30th day after PVP injection into thigh muscle. The local reaction of muscular tissue was macroscopically characterized with inflammatory reaction till the 7th day after PVP injection, in later terms the observed changes disappeared. Microscopic research showed that PVP till the 7th day after PVP injection caused rather strong diffuse non-specific inflammatory process, yet without essential participation of neutrophils leading to producing of loose intra-muscular. Connective tissue in a later term. The carried out tests showed presence of PVP in muscular tissue till the 30th day after injection.  相似文献   
64.
Internally netted miscogelatinated preparation on the basis of polyvinylpyrrolidone PVP desioned for viscosuplementation of joint fluid was worked out. Netted structure of microgel grains presents larger resistance to the degrading action of free radicals than analogical linear polymer chains. Application of zoogeous preparations of hyaluronic acid results in short-term effects of their usage in evoking reaction foreign protein. Replenishment of joint fluid with preparation with higher biostability from biocompatible synthetic polymer-polyvinylpyrrolidone could improve the function of synovial through restoration of its proper viscosity and protection of the joint for a longer period of time. The aim of the experiment was determination of bioresistance and reaction of microgel PVP on the tissues of synovial joint. The tests were carried out on 10 white New Zealand rabbits after injection PVP into the knee joint for 3, 7, 14 and 30 days and submitted to macroscopic and histological evaluation. The results of tests were compared with the data obtained after injection of normal saline. Macroscopically, there were no changes in the limits of articular capsule and cartilage; there was only slight and enlargement of synovial membrane in the first 7 days after PVP injection. In histological tests it was observed that reaction in the knee joint after PVP injection was characterised it single inflammatory chains without essential participation of neutrophils observed only in synovial membrane and limited to places were tested preparation was seen. Microgel PVP was present in diverticula of synovial membrane to 30th day after injection.  相似文献   
65.
OBJECTIVE: To determine the contemporary clinical relevance of acute lower extremity ischemia and the factors associated with amputation and in-hospital mortality. SUMMARY BACKGROUND DATA: Acute lower extremity ischemia is considered limb- and life-threatening and usually requires therapy within 24 hours. The equivalency of thrombolytic therapy and surgery for the treatment of subacute limb ischemia up to 14 days duration is accepted fact. However, little information exists with regards to the long-term clinical course and therapeutic outcomes in these patients. METHODS: Two databases formed the basis for this study. The first was the National Inpatient Sample (NIS) from 1992 to 2000 of all patients (N = 23,268) with a primary discharge diagnosis of acute embolism and thrombosis of the lower extremities. The second was a retrospective University of Michigan experience from 1995 to 2002 of matched ICD-9-CM coded patients (N = 105). Demographic factors, atherosclerotic risk factors, the need for amputation, and in-hospital mortality were assessed by univariate and multivariate logistic regression analysis. RESULTS: In the NIS, the mean patient age was 71 years, and 54% were female. The average length of stay (LOS) was 9.4 days, and inflation-adjusted cost per admission was $25,916. The amputation rate was 12.7%, and mortality was 9%. Decreased amputation rates accompanied: female sex (0.90, 0.81-0.99), age less than 63 years (0.47, 0.41-0.54), angioplasty (0.46, 0.38-0.55), and embolectomy (0.39, 0.35-0.44). Decreased mortality accompanied: angioplasty (0.79, 0.64-0.96), heparin administration (0.50, 0.29-0.86), and age less than 63 years(0.27, 0.23-0.33).The University of Michigan patients' mean age was 62 years, and 57% were men. The LOS was 11 days, with a 14% amputation rate and a mortality of 12%. Prior vascular bypasses existed in 23% of patients, and heparin use was documented in 16%. Embolectomy was associated with decreased amputation rates (0.054, 0.01-0.27) and mortality (0.07, 0.01-0.57). CONCLUSIONS: In patients with acute limb ischemia, the more widespread use of heparin anticoagulation and, in select patients, performance of embolectomy rather than pursuing thrombolysis may improve patient outcomes.  相似文献   
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67.
OBJECTIVE: This study was undertaken to determine the relative importance of surgeon specialty, hospital volume, and surgeon volume on outcome after abdominal aortic aneurysm (AAA) repair. METHODS: Data were reviewed for 3912 patients undergoing AAA repair in the Nationwide Inpatient Sample during 1997. In-hospital mortality was compared between high-volume hospitals and low-volume hospitals and between high-volume surgeons and low-volume surgeons. High-volume hospitals performed more than 35 AAA repairs per year, and high-volume surgeons performed more than 10 AAA repairs per year. Vascular, cardiac, and general surgery specialization was identified by analysis of other procedures performed by each surgeon. RESULTS: Overall, AAA repair mortality was 4.2%, and was lower at high-volume hospitals (3.0%) than at low-volume hospitals (5.5%) (P <.001). Lowest mortality was associated with operations performed by vascular surgeons (2.2%) compared with cardiac surgeons (4.0%) and general surgeons (5.5%) (P <.001). Mortality rates were also lower for high-volume hospitals (2.5%) compared with low-volume hospitals (5.6%) (P <.001). In a risk-adjusted analysis, high-volume hospital, vascular surgery specialty, and high-volume surgeon were all independently associated with lower risk of in-hospital mortality. In this analysis, risk reduction was 30% for high-volume hospitals (95% confidence interval [CI], 2%-51%; P <.05) and 40% for surgery by a high-volume surgeon (95% CI, 12%-60%; P =.01). AAA repair by general surgeons compared with vascular surgeons was associated with 76% greater risk for death (95% CI, 10%-190%; P =.02). No significant difference in mortality was found between cardiac and vascular surgeons. CONCLUSIONS: High surgeon volume and hospital volume of AAA repair were both associated with lower mortality compared with low-volume providers. Increased specialization in vascular surgery was associated with markedly decreased mortality independent of AAA repair volume. Health policy in support of selective referral for AAA repair should consider surgical specialization in addition to provider volume thresholds.  相似文献   
68.
Magnetic Drug Targeting means the specific delivery of chemotherapeutic agents to their desired targets, e.g. tumors, by using magnetic nanoparticles (ferrofluids) bound to these agents and an external magnetic field which is focused on the tumor. This type of target directed drug injection attempts to concentrate a pharmacologic agent by enhancing its efficacy while simultaneously minimizing deleterious side effects. In previous studies, we have been able to demonstrate the efficacy of this type of localized intraarterial chemotherapy in VX2 squamous cell carcinoma among rabbits [Alexiou, C., Arnold, W., Klein, R.J., Parak, F.G., Hulin, P., Bergemann, C., Erhardt, W., Wagenpfeil, S. and Lübbe, A.S. "Locoregional cancer treatment with Magnetic Drug Targeting", Cancer Res. 60 (2000) 6641-6648]. In the present investigation, we have studied the biodistribution of ferrofluids and chemotherapeutic agent by measuring the amount in the tumor, peritumoral area, various organs and body fluids (e.g. blood and urine), with and without Magnetic Drug Targeting. We compared results to that of administering a chemotherapeutic agent soley. An external magnetic field was directed toward the tumor for 60 min. Biodistribution of ferrofluids in the tumor was investigated using histological cross sections and measured semi-quantitatively using 123I-labeled nanoparticles and quantitatively by the use of radioactive 59Fe-ferrofluids. Mitoxantrone was quantitatively measured using HPLC-analysis. The strength of the external magnetic field was 0.6 Tesla (permanent magnet) in the 123iodine study and 1.7 Tesla (electromagnet) in the 59Fe-study and HPLC-analysis. The concentration of the ferrofluids (FFs) in the tumor region i.e. the tumor tissue and the surrounding area, which was under the influence of an external magnetic field, was found to be much higher than in the absence of one. In contrast to systemic chemotherapy, a much higher concentration of mitoxantrone in the tumor and the peritumoral area (region surrounding the tumor < or = 1 cm), by using only 50% and 20% of the normal dose was seen. Thus, the higher concentration of mitoxantrone could explain the therapeutic efficacy of Magnetic Drug Targeting in treatment of VX2 squamous cell carcinoma in rabbits in our previous studies with the advantage of no adverse clinical side effects.  相似文献   
69.
The fibroblast growth factor-binding protein (FGF-BP) binds and activates fibroblast growth factors in the extracellular matrix, and can have a rate-limiting role in tumor angiogenesis. Here we demonstrate high levels of FGF-BP expression in invasive human breast cancer, relative to normal breast and in situ carcinoma, and in MDA-MB-468 human breast cancer cells. In these cells, FGF-BP was up-regulated by treatment with epidermal growth factor (EGF), dependent on protein kinase C and p38 mitogen-activated protein kinase signaling. Mutational analysis revealed that the activator protein 1 and CCAAT/enhancer binding protein (C/EBP) sites on the FGF-BP gene promoter were required for the EGF effect, whereas deletion of the C/EBP site resulted in a significant increase in promoter basal activity indicating a basal repressive control mechanism. These data suggest that the C/EBP site is a central regulatory element for the regulation of FGF-BP promoter activity in MDA-MB-468 cells. We found that MDA-MB-468 cells express high endogenous levels of both the activating (LAP) and repressive (LIP) isoforms of C/EBPbeta. Overexpression of C/EBPbeta-LAP in MDA-MB-468 cells resulted in a large 80-fold increase in FGF-BP promoter basal activity, which was reversed by coexpression of LIP. Gel-shift analysis revealed that four LIP- and LAP-containing complexes (a-d) bind to the C/EBP site. DNA binding of the LIP and LAP-containing c complex and the b complex in the presence of EGF was modulated by inhibition of p38 mitogen-activated protein kinase, suggesting a role for these complexes in the EGF induction of the FGF-BP promoter. This study suggests that along with its well-defined role in mammary gland development, C/EBPbeta may well play a role in the pathology of breast cancer, in particular in the control of angiogenesis in the invasive phenotype.  相似文献   
70.
Patient satisfaction is an important outcome measure independent of other outcomes. Its measurement is important to assess the effectiveness of a programme and to gain insight into the patients'' perception of the programme. In this study conducted in a large rehabilitation centre it was found that majority of patients express satisfaction with care inspite of perceived discomfort. Various demographic factors, severity or duration of the disability or the level of rehabilitation do not influence patient satisfaction. Patients express more concern with aspects such as delay in issue of the prosthesis, or hotel component of the hospital services. Patients did not appear too concerned about the level of information provided. Patient satisfaction is an individual reaction to the overall care process and is influenced by the initial expectation level of the patient. Emotional response of the patient appears to be more important determinant of patient satisfaction than the cognitive evaluation. Periodical assessment of patient satisfaction should be an important component of any programme evaluation exercise.KEY WORDS: Amputation, Patient satisfaction, Programme evaluation, Prosthesis, Quality of care, Rehabilitation  相似文献   
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