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91.
Abenstein JP Long KH McGlinch BP Dietz NM 《Anesthesia and analgesia》2004,98(3):750-7, table of contents
One of the most controversial issues in anesthesia is whether nonmedically directed nurse anesthetists are relatively more cost-effective than anesthesiologists in the provision of anesthesia care. We electronically surveyed anesthesia practices throughout the United States to estimate the range in anesthesia professional costs from the payer perspective. Using this survey data on anesthesia reimbursement and published outcomes studies, we developed an ad hoc model to estimate the cost-effectiveness of physician-directed anesthesia relative to a nonmedically directed nurse anesthetist model of care from the payer perspective. Cost-effectiveness ratios were defined as the ratio of incremental costs associated with physician anesthesia relative to the estimated incremental life expectancy gains with this model of care (i.e., dollars per year of life saved [US dollars /YLS]). Reference case results suggest that physician anesthesia is cost saving with an estimated incremental cost-effectiveness ratio of -US dollars 2601/YLS for a younger privately insured patient and an estimated cost-effectiveness ratio of -US dollars 4410/YLS for an elderly Medicare insured patient. Cost-effectiveness ratios ranged from -US dollars 4410 to US dollars 38778/YLS in univariate and multivariate sensitivity analyses across payer types. Results were most sensitive to assumed differences in reimbursement (commercial conversion factors) and to mortality rate assumptions by provider type. This analysis offers economic evidence in support of the physician anesthesia model of care. IMPLICATIONS: Recent outcome studies suggest improved patient outcomes when physicians medically direct nurse anesthetists versus anesthesia care delivered with nonmedically directed nurses. The relative cost-effectiveness of this practice model is, however, unknown. This economic analysis suggests that outcome gains with physician anesthesia may be obtained at cost savings or, under conservative assumptions, at a cost deemed reasonable by society. 相似文献
92.
Shibahara J Goto A Niki T Tanaka M Nakajima J Fukayama M 《The American journal of surgical pathology》2004,28(6):825-829
We describe a case of primary pulmonary paraganglioma, a tumor that has not been reported in sufficient detail in previous literature. The patient was a 55-year-old woman with hypertension accompanied by an elevated serum norepinephrine level (2651 pg/mL; normal 100-450 pg/mL). Computed tomography revealed a well-circumscribed solid mass, 3.5 cm in diameter, located in the lower lobe of the left lung. In the lobectomy specimen, the tumor had invaded the B8 bronchus and hilar lymph nodes with microscopic metastasis to the mediastinal nodes. The tumor showed histologic, immunohistochemical, and ultrastructural features of paraganglioma: argyrophilic cells arranged in a nesting (Zellballen) or anastomosing trabecular pattern within an arcuate vascular network. Neoplastic chief cells positive for neuroendocrine markers (CD56, synaptophysin, chromogranin A) were surrounded by sustentacular cells positive for S-100 protein. Neurofilament protein was positively stained, but cytokeratins were totally negative. On electron microscopy, chief cells possessed abundant dense core granules with an eccentric halo ("norepinephrine-type" granules). The patient's blood pressure began to decline soon after the resection, and her serum norepinephrine promptly returned to almost normal. On the basis of our experience, our case is a bona fide primary pulmonary paraganglioma, a tumor heretofore subject to considerable skepticism. 相似文献
93.
94.
Acromegaly, a multisystemic disease resulting from excessive growth hormone (GH) and insulin-like growth factor-I (IGF-I) levels in adults, is associated with a two-to-threefold increase in mortality. The available treatment options (surgery, radiotherapy and medical treatment with somatostatin analogues or dopamine agonists) fail to achieve the currently accepted goals of therapy in a substantial number of patients. Pegvisomant, a newly developed GH receptor antagonist, represents a novel treatment modality for this disease. It binds with the GH receptor and induces internalization, but blocks receptor signaling events, thereby reducing IGF-I production. The two main published studies suggest that it is the most potent medical therapy with greater specificity, without being dependent on the tumour characteristics. However, apart from its high cost and the dilemmas raised concerning the appropriateness of using serum IGF-I concentrations as a marker of disease activity, it may also occasionally be associated with elevations in liver enzyme levels. Further studies are required to confirm its high success rates as well as to investigate the possibility of inducing an increase in the pituitary tumour size. Currently, pegvisomant is a second line treatment for acromegaly with an adjuvant role and possibly of greater value in cases of resistance to other therapeutic options. 相似文献
95.
Cranial magnetic resonance imaging in genetically proven myotonic dystrophy type 1 and 2 总被引:1,自引:0,他引:1
Kornblum C Reul J Kress W Grothe C Amanatidis N Klockgether T Schröder R 《Journal of neurology》2004,251(6):710-714
Abstract.
Cranial magnetic resonance imaging (MRI) in 19 German patients with genetically proven myotonic dystrophy Type 1 (DM1, n = 10) or Type 2 (DM2, n = 9) showed pathological findings consisting of white matter lesions (WML) and/or brain atrophy in 9/10 DM1 and 8/9 DM2 patients. Anterior temporal WML (ATWML) were exclusively seen in DM1 patients. Our findings indicate a high frequency of central nervous system (CNS) involvement in both disorders. However, temporopolar pathology, previously associated with intellectual dysfunction, seems to be restricted to DM1. 相似文献
96.
Aberrant mucosal wound repair in the absence of secretory leukocyte protease inhibitor 总被引:5,自引:0,他引:5
Angelov N Moutsopoulos N Jeong MJ Nares S Ashcroft G Wahl SM 《Thrombosis and haemostasis》2004,92(2):288-297
Secretory leukocyte protease inhibitor (SLPI) is a cationic serine protease inhibitor with anti-microbial and anti-inflammatory properties found in large quantities in mucosal fluids, including saliva. SLPI is expressed during cutaneous wound healing, however, its role in oral wound repair is unknown. We have used a novel approach involving a murine buccal mucosal acute wound model to investigate the role of SLPI in oral healing. In parallel to the observed cutaneous healing phenotype, an absence of SLPI results in markedly impaired oral wound healing associated with increased inflammation and raised elastase activity. Moreover, matrix deposition was decreased, while MMP activity was enhanced in the oral SLPI null wounds suggesting deregulated proteolysis. Intriguingly, regardless of genotype, reduced collagen deposition was observed in oral compared to dermal wounds, associated with reduced TGF-beta expression and decreased fibroblast collagen expression in vitro. We propose that SLPI is a pivotal endogenous factor necessary for optimal tissue repair including intra-oral wound healing. In addition, our model provides a unique opportunity to delineate the cellular and molecular mechanisms underlying the differences between dermal scarring and oral scar-free healing. 相似文献
97.
Stefanou D Batistatou A Kamina S Arkoumani E Papachristou DJ Agnantis NJ 《In vivo (Athens, Greece)》2004,18(2):155-160
BACKGROUND: Tumor angiogenesis is an absolute requirement for tumor growth and a prognostic factor for various malignant neoplasms. Recent reports in the literature have addressed the importance of the VEGF system in benign prostatic hyperplasia (BPH) and adenocarcinoma, however the results are controversial. The aim of the present study was to determine and compare the levels of VEGF expression and vascularity in BPH and prostate carcinoma. MATERIALS AND METHODS: We examined 60 prostate adenocarcinomas and 64 benign prostatic hyperplasias. Angiogenesis was estimated by determining microvessel counts (MVC), with the use of anti-CD31 and anti-CD34 antibodies. Expression of VEGF was also evaluated immunohistochemically. RESULTS AND CONCLUSION: Our data showed that angiogenesis was more prominent in carcinomas than in BPH. Furthermore, increased MVC was significantly associated with high-grade carcinomas. Angiogenesis was correlated with VEGF expression and it was, at least in part, mediated by the latter. Thus, prostate adenocarcinoma may represent a suitable neoplasm for antiangiogenic treatment in combination with conventional therapies. 相似文献
98.
Hamaguchi T Matsumura Y Nakanishi Y Muro K Yamada Y Shimada Y Shirao K Niki H Hosokawa S Tagawa T Kakizoe T 《Cancer science》2004,95(7):608-613
MCC-465 is an immunoliposome-encapsulated doxorubicin. The liposome is tagged with polyethylene glycol and the F(ab')2 of a monoclonal antibody named GAH, a human antibody obtained by the hybridoma technique. The epitope recognized by GAH is not well characterized, but human gastric, colorectal, and mammary cancer cells were GAH-positive, while the normal counterparts were GAH-negative. Pegylated liposome doxorubicin (PLD) and MCC-465 did not show significant antitumor activity against GAH-negative Caco-2 xenografts. On the other hand, MCC-465 exhibited significantly superior antitumor effects against GAH-positive WiDr-Tc and SW837 xenografts, compared with PLD. Immunohistochemistry with GAH revealed that 94% (100 of 106) of surgical specimens of colorectal cancer were GAH-positive. These results warrant a phase I clinical trial of MCC-465 for patients with metastatic colorectal cancer. 相似文献
99.
In the present study the effects of seasonal solar radiation (summer and winter) on exposed populations of two different age groups (20-25 and 40-55 years old) were investigated. In addition, the effects of external factors, such as hydrogen peroxide (H(2)O(2)) and gamma-irradiation, as well as the repair efficiency of human lymphocytes from these populations, was also evaluated. Our results show that the amount of DNA damage appears to be influenced by the exposure to solar radiation, with the summer exposure being the most damaging. Age was also found to be a significant factor, with the older population being more susceptible to solar radiation than the younger one. Season does not appear to affect the sensitivity to external DNA-damaging agents, while age does. Age was also found to have an effect on the DNA repair capacity of the examined populations. 相似文献
100.
Delivery outcomes following loop electrosurgical excision procedure for microinvasive (FIGO stage IA1) cervical cancer 总被引:10,自引:0,他引:10
Paraskevaidis E Koliopoulos G Lolis E Papanikou E Malamou-Mitsi V Agnantis NJ 《Gynecologic oncology》2002,86(1):10-13
OBJECTIVE: The goal of this study was to report the delivery outcomes in women who had loop electrosurgical excision procedure (LEEP) for microinvasive cervical cancer (stage IA1 without lymphovascular invasion) and became pregnant and progressed beyond 24 weeks. METHODS: A case-control study was performed. Twenty-eight women who were managed exclusively with LEEP for microinvasive cervical carcinoma had at least one pregnancy beyond 24 weeks and were the cases. Each case was matched with one woman who delivered at the same department without prior treatment of her cervix (controls) and their delivery outcomes were compared with those of the cases. Known risk factors for preterm delivery were used as matching factors. RESULTS: There was no statistically significant difference (P > 0.05) between cases and controls in the duration of pregnancy (37.6-38.4 weeks respectively), birth weight (3212-3315 g), cesarean section rate (17.8-32.1%), neonatal unit admission rate (21.4-10.7%), and precipitate labor rate (13-10.5%). The duration of labor was significantly shorter in cases (5.5-7.1 h, P = 0.032). After LEEP the relative risk for preterm delivery is 3.67 (95% confidence interval, 0.97-20.27), for low birth weight infant 0.67 (0.06-5.8), for precipitate labor 1 (0.05-3.88), and for delivery by cesarean section 0.5 (0.17-4.46). CONCLUSIONS: Women treated for microinvasive cancer with LEEP did not have significantly more delivery complications compared with controls apart from shorter duration of labor. There was a possible non-statistically significant trend toward shorter duration of pregnancy in cases. While caution should be advised when selecting and treating women with microinvasive carcinoma by LEEP, the apparent safety of the management and the satisfactory delivery outcome seem to justify this approach in many cases. 相似文献