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In this paper we use nonparametric mathematical programming models to compute and decompose Malmquist indices of productivity and quality change, which are used to evaluate the reforms in the UK National Health Service in the early nineties. We focus on acute hospitals and we study them over the first five years of the reforms. The findings of the study indicate that there was a productivity slowdown in the first year after the reforms but productivity progress in the subsequent years and thus, overall there was a net gain in productivity over the entire period considered. Productivity trends were dominated by technical change rather than hospital relative efficiency changes, as hospitals were already largely relatively efficient at the time of the introduction of the reforms. In fact, over the last four years in the period studied there was small relative efficiency regress and this does not bear out the argument that the reforms would increase hospital efficiency. The productivity changes are similar when service quality is incorporated in the analysis but the magnitude of these changes diminishes. Quality of service followed different trends to productivity change and this may have been the price for the productivity gains achieved. 相似文献
23.
Laparoscopic Cholecystectomy in Obese and Nonobese Patients 总被引:2,自引:1,他引:1
Gatsoulis N Koulas S Kiparos G Tzafestas N Pangratis K Pandis K Mavrakis G 《Obesity surgery》1999,9(5):459-461
Background: From November 1997 to November 1998, 145 cases of laparoscopic cholecystectomy (LC) have been attempted at the
District General Hospital of Corfu. Methods: 23 (15.8%) were obese (Group I, BMI >30) and 122 (84.2%) were nonobese patients
(Group II, BMI ≤30). One-fifth of these patients suffered from acute cholecystitis. Results: Operative time averaged 95 minutes
in Group 1 and 78 minutes in Group II. There were no deaths. There were no significant differences between the obese and nonobese
groups in conversion to open procedure (Group1: 0%, Group II: 2.4%), intraoperative and postoperative complications (Group
I: 4.3%, Group II: 4.0%), operating time, and length of postoperative hospitalization. Conclusion: LC was a safe and effective
treatment for obese patients with symptomatic cholelithiasis. 相似文献
24.
Thomas Martin Sandra R?ddiger Ralf Kurek Thomas Dannenberg Oliver Eckart Christos Kolotas Reinhard Heyd Bernd Rogge Dimos Baltas Ulf Tunn Nikolaos Zamboglou 《Radiotherapy and oncology》2004,71(1):35-41
PURPOSE: To evaluate treatment outcome of 3D conformal high dose rate (HDR) brachytherapy and external beam irradiation (EBRT) combined with temporary androgen deprivation for patients with localized prostate cancer. PATIENTS AND METHODS: Between January 1997 and September 1999 we treated 102 patients with stage T1-3 N0 M0 prostate cancer. Stage T1-2 was found in 71, T3 in 31 patients. Median pretreatment PSA level was 15.3 ng/ml. After ultrasound-guided transrectal implantation of four afterloading needles, CT based 3D brachytherapy planning was performed. All patients received four HDR implants using a reference dose per implant of 5 or 7Gy. Time between each implant was 14 days. After brachytherapy EBRT followed up to 39.6 or 45.0 Gy. All patients received temporary androgen deprivation, starting 2-19 months before brachytherapy, ending 3 months after EBRT. RESULTS: Median follow-up was 2.6 years (range 2.0-4.1 years). Actuarial biochemical control rate was 87% at 2 years and 82% at 3 years. In 14 patients we noted biochemical failure, in five patients clinical failure. Overall survival was 90%, disease specific survival 98.0% at 3 years. Acute grade 3 toxicity occurred in 4%, late grade 3 toxicity in 5%. One patient developed a prostatourethral-rectal fistula as late grade 4 toxicity. The conformal quality of 300 HDR implants was analyzed using dose volume histograms. CONCLUSIONS: 3D conformal HDR brachytherapy and EBRT combined with temporary androgen deprivation is an effective treatment modality for prostate cancer with minimal associated toxicity and encouraging biochemical control rates after a median follow-up of 2.6 years. 相似文献
25.
M A Dimopoulos G Hamilos K Zervas A Symeonidis G Kouvatseas P Roussou D Gika T Karmiris K Bourantas A Zomas C Mitsouli I Xilouri E Vervessou K Matsis N Anagnostopoulos T Economopoulos 《Annals of oncology》2003,14(8):1299-1305
BACKGROUND: Waldenstrom's macroglobulinemia (WM) is an unusual lymphoplasmacytoid lymphoma characterized by the presence of a serum monoclonal immunoglobulin M. Although several studies have evaluated possible prognostic factors of this disease, few have focused on the survival and prognosis of symptomatic patients after the initiation of treatment. PATIENTS AND METHODS: Our study included 122 previously untreated patients with a median age of 67 years who required systemic treatment. Multiple variables were analyzed for their prognostic value on survival after initiation of treatment using univariate and Cox regression multivariate analysis. RESULTS: The median overall survival was 106 months. Pretreatment factors associated with shorter survival were age >/=65 years, splenomegaly, B-symptoms (weight loss, fever or night sweats), hemoglobin <10 g/dl, platelets <100 x 10(6)/dl, albumin <3.5 g/dl and bone marrow lymphoplasmacytic infiltrate >/=50%. In the multivariate analysis, the two variables with independent prognostic value were age >/=65 years and hemoglobin <10 g/dl. Furthermore, we were able to divide our patients into three risk groups based on the presence of two, one or none of these two adverse prognostic factors. The median survival times in the high-, intermediate- and low-risk groups were 46 months, 107 months and 172 months, respectively (P <0.0001). DISCUSSION: Our findings suggest that advanced age and anemia appear to be the two dominant prognostic factors for survival after initiation of treatment in patients with WM. These two readily available parameters can stratify the patients into three distinct subgroups and may help the selection of appropriate treatment. 相似文献
26.
Steven P Treon Mark Hansen Andrew R Branagan Sigitas Verselis Christos Emmanouilides Eva Kimby Stanley R Frankel Nikolaos Touroutoglou Barry Turnbull Kenneth C Anderson David G Maloney Edward A Fox 《Journal of clinical oncology》2005,23(3):474-481
PURPOSE: Rituximab is an important therapeutic for Waldenstrom's macroglobulinemia (WM). Polymorphisms in FcgammaRIIIA (CD16) receptor expression modulate human immunoglobulin G1 binding and antibody-dependent cell-mediated cytotoxicity, and may therefore influence responses to rituximab. PATIENTS AND METHODS: Sequence analysis of the entire coding region of FcgammaRIIIA was undertaken in 58 patients with WM whose outcomes after rituximab were known. RESULTS: Variations in five codons of FcgammaRIIIA were identified. Two were commonly observed (FcgammaRIIIA-48 and FcgammaRIIIA-158) and predicted for amino acid polymorphisms at FcgammaRIIIA-48: leucine/leucine (L/L), leucine/arginine (L/R), and leucine/histidine (L/H). Polymorphisms at FcgammaRIIIA-158 were phenylalanine/phenylalanine (F/F), phenylalanine/valine (F/V), and valine/valine (V/V). A clear linkage between these polymorphisms was detected and all patients with FcgammaRIIIA-158F/F were always FcgammaRIIIA-48L/L, and patients with either FcgammaRIIIA-L/R or -L/H always expressed at least one valine at FcgammaRIIIA-158 (P < or = .001). The response trend was higher for patients with FcgammaRIIIA-48L/H (38.5%) versus -48L/R (25.0%) and LL (22.0%), and was significantly higher for patients with FcgammaRIIIA-158V/V (40.0%) and -V/F (35%) versus -158F/F (9.0%; P = .030). Responses for patients with FcgammaRIIIA-48L/L were higher when at least one valine was present at FcgammaRIIIA-158 (P = .057), thereby supporting a primary role for FcgammaRIIIA-158 polymorphisms in predicting rituximab responses. With a median follow-up of 13 months, no significant differences in the median time to progression and progression-free survival were observed when patients were grouped according to their FcgammaRIIIA-48 and -158 polymorphisms. CONCLUSION: The results of these studies therefore support a predictive role for FcgammaRIIIA-158 polymorphisms and responses to rituximab in WM. 相似文献
27.
Charalampos Siristatidis Konstantinos Dafopoulos Nikolas Christoforidis George Anifandis Vasileios Pergialiotis Nikolaos Papantoniou 《Gynecological endocrinology》2017,33(12):968-971
Recombinant DNA technologies have produced Corifollitropin alfa (CFa) used during IVF/ICSI in order to keep the circulating FSH levels above the threshold necessary to support multi-follicular growth for a week. In this prospective case-control study, we compared 70 participants treated with 150?μg CFa combined with 150?IU of follitropin beta (study group) with 70 subfertile participants with matching baseline characteristics, conforming with the same inclusion criteria and treated with an antagonist protocol using follitropin beta (control group). Live birth was the primary outcome, while secondary outcome measures were IVF/ICSI cycles characteristics, including adverse events and complications. Live birth was determined in reduced rates in the study compared to the control group, reaching statistical significance [6/70 versus 20/70, p?=?0.002], as also in the respective number of clinical pregnancies [9/70 versus 23/70, p?=?0.005], although the incidence of miscarriage was similar for both groups [6/70 versus 5/70, p?>?0.99]. Most of the secondary parameters examined were similar between groups. Logistic regression revealed that protocol and AFC had a direct impact on live birth. Ovarian stimulation with CFa does not seem to constitute an equally effective method as compared with follitropin beta to be offered in a general subfertile population seeking IVF/ICSI treatments. 相似文献
28.
Panagiotis M. Angelopoulos Nikolaos Rafael Vrithias Zacharias Viskadourakis Petros Tsakiridis Konstantinos C. Vasilopoulos Antonis Peppas Georgios Asimakopoulos Anastasia V. Spyrou Michael A. Karakassides Maria Taxiarchou George Kenanakis 《Materials》2022,15(14)
The use of amorphous microspheres as filler in composites is promising due to their light weight, low cost, incombustibility, and the ability to alter relevant properties of the final composite. Contrary to glass spheres, perlite microspheres are much cheaper and can be tailor-made to facilitate purpose-oriented alteration of the final composite. We report the use of perlite microspheres for the preparation of: (1) composites, through a compression molding (hot pressing) technique; and (2) composite filaments, in a single screw extruder, as well as their use for sample printing through Fused Deposition Modeling (FDM). Proper characterization of the produced composites allows for their evaluation in terms of physical, thermal, and mechanical properties and with regards to the manufacturing technique, the filler fraction, and size. Composite samples of acceptable quality in terms of filler survival and dispersion as well as mechanical properties were produced through compression molding using fine expanded perlite microspheres (<90 μm) up to an infill ratio of 40 vol.%. Fine fillers (<90 μm) performed well in FDM, allowing printing of composite dogbone samples with a higher Young’s modulus and elongation and similar ultimate tensile strength compared to benchmark, up to an infill ratio of 20 vol.%. Composite samples present a slightly lower burning rate compared to those produced solely by ABS. Perlite microspheres present good workability in both applications, possessing satisfactory performance as filler in the composites, and can thus be assumed a promising multifunctional filler for various thermoplastics considering their low price, environmental impact, and fire rating. 相似文献
29.
30.
Polyzos NP Tsappi M Mauri D Atay V Cortinovis I Casazza G 《Fertility and sterility》2008,89(2):278-280
A meta-analysis of four trials showed significant advantage in pregnancy and delivery rates with aromatase inhibitors compared with CC in women with PCOS. A recent randomized trial demonstrated no clear benefit. 相似文献