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41.
Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers, indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999 to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944 for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between 1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units. Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
42.
The aim of this study was to estimate costs accrued by the health care of children with asthma in comparison to children with atopic eczema and seasonal rhinitis and to investigate cost determinants. From the multicenter cohort study (MAS-90), we selected children with an asthma, atopic eczema and/or seasonal rhinitis diagnosis during the first 8 years of life, and overall 8-year health care utilization was estimated retrospectively by reviewing medical records. Asthma treatment (n = 76) incurs an average cost of US$ 627 per year, 44% due to hospital stays. Atopic eczema treatment (n = 91) cost on average US$ 219 and seasonal rhinitis (n = 69) US$ 57 per year. In asthma and atopic eczema, costs increase significantly with disease severity. Allergy diagnostics use accounts for only 1% of total costs. Costs for asthma and atopic eczema treatment are highest in those years when topical steroids are used for the first time, but decrease with every further year of steroid use. A remarkable 25% of asthmatic children with severe symptoms were not treated according to national guidelines, so that most steroid treatment was initiated during the first hospital stay. In the case of asthma, total direct costs increased until the 3rd year of the disease, and then decreased with further years of diagnosis, while steroid use continued to increase. These results indicate a 'learning effect' in the treatment of asthma and atopic eczema for each patient as well as considerable cost-saving potential by preventing severe asthma. Moreover, the importance of considering cost-driving factors and using cohort or longitudinal designs in cost-of-illness approaches is emphasized.  相似文献   
43.
To determine if transforming growth factor alpha (TGFα) pretreatment protects hair cells from aminoglycoside induced injury by modifying their intracellular calcium concentration, we assayed hair cell calcium levels in organ of Corti explants both before and after aminoglycoside (i.e. neomycin, 10−3M) exposure either with or without growth factor pretreatment. After TGFα (500ng/ml) treatment, the intracellular calcium level of hair cells showed a five-fold increase as compared to the levels observed in the hair cells of control cultures. After ototoxin exposure, calcium levels in hair cells of control explants showed an increase relative to their baseline levels, while in the presence of growth factors pretreatment, hair cells showed a relative reduction in calcium levels. Pretreatment of organ of Corti explants afforded significant protection of hair cell stereocilia bundle morphology from ototoxic damage when compared to explants exposed to ototoxin alone. This study correlates a rise in hair cell calcium levels with the otoprotection of hair cells by TGFα in organ of Corti explants.  相似文献   
44.
The pharmacokinetic behaviour of the 131-iodine-labelled title compound 3 * and its metabolites in mice was investigated. A two phase, 1st order elimination profile was observed. The second phase is very slow leaving about 35% of radioactivity in the mice even 100h after i.v. injection, because of high affinity to liver and spleen, caused by strong binding of oligoamines to phospholipids of liver and blood cell membranes. The blood-brain-barrier is not passed. No deep compartments were observed. The doses necessary for antithrombotic effects in vivo were calculated from the blood levels to be 20.5–39.7 μmol/kg for a time interval of 1–6 h after administration.  相似文献   
45.
The metabolic fate of the benzodiazepine antagonist RO 15-1788 labelled with 11C was studied in plasma from human subjects after intravenous administration in connection with positron emission tomography. Ro 15–1788 and its metabolites were separated by thin-layer chromatography and the radioactivity in the different compounds was determined. 11C-Ro 15–1788 was extensively and rapidly metabolised to the corresponding free acid. At 36 minutes after administration only 50% of the radioactivity in plasma represented unchanged compound.  相似文献   
46.
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241. This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection. The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage. Received 19 April and in revised form 10 June 1997  相似文献   
47.
48.
A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc.  相似文献   
49.
50.
Phosphorus was imaged in vivo in human cortical and trabecular bone and the T(1) and T(2) (*) were measured. An ultrashort TE (UTE) pulse sequence (TE = 70 microm) was used with half pulse excitation and radial mapping of k-space from the center out. T(2) (*) was measured using multiple echo times and T(1) was measured both by saturation recovery and by a method using different RF pulse amplitudes. Seven normal subjects (32-85 years) were examined. Phosphorus was imaged, with a true in-plane resolution of 2.9 x 2.9 mm and a signal-to-noise ratio (SNR) of 19:1, in both cortical and trabecular bone. The mean T(2) (*) value was 207 +/- 12 micros, and the mean T(1) value was 8.6 +/- 3.0 sec. Images and measurements were obtained in realistic times on a clinical MR system. This may provide a new approach to characterizing disease of bone.  相似文献   
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