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31.
Zach Pennington Jeff Ehresman James Feghali Andrew Schilling Andrew Hersh Bethany Hung Daniel Lubelski Daniel M. Sciubba 《The spine journal》2021,21(2):302-311
BACKGROUND CONTEXTSurgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.PURPOSETo develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.STUDY DESIGN/SETTINGRetrospective, single-center study.PATIENT SAMPLEConsecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer centerOUTCOME MEASURESIOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.METHODSWe identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.RESULTSMean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=?244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).CONCLUSIONSHere we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion. 相似文献
32.
Wenjie Bi Anke Kraft Sophie Engelskircher Jasmin Mischke Moana Witte Frank Klawonn Marco van Ham Markus Cornberg Heiner Wedemeyer Julia Hengst Lothar Jänsch 《European journal of immunology》2023,53(11):2250291
Chronic hepatitis C virus (HCV) infections compromise natural killer (NK)-cell immunity. Direct-acting antivirals (DAA) effectively eliminate HCV, but the long-term effects on NK cells in cured patients are debated. We conducted a proteomic study on CD56+ NK cells of chronic HCV-infected patients before and 1 year after DAA therapy. Donor-variation was observed in NK-cell proteomes of HCV-infected patients, with 46 dysregulated proteins restored after DAA therapy. However, 30% of the CD56+ NK-cell proteome remained altered 1 year post-therapy, indicating a phenotypic shift with low donor-variation. NK cells from virus-negative cured patients exhibited global regulation of RNA-processing and pathways related to “stimuli response”, “chemokine signaling”, and “cytotoxicity regulation”. Proteomics identified downregulation of vesicle transport components (CD107a, COPI/II complexes) and altered receptor expression profiles, indicating an inhibited NK-cell phenotype. Yet, activated NK cells from HCV patients before and after therapy effectively upregulated IFN-γ and recruited CD107a. Conversely, reduced surface expression levels of Tim-3 and 2B4 were observed before and after therapy. In conclusion, this study reveals long-term effects on the CD56+ NK-cell compartment in convalescent HCV patients 1 year after therapy, with limited abundance of vesicle transport complexes and surface receptors, associated with a responsive NK-cell phenotype. 相似文献
33.
Norbert Donner-Banzhoff Lothar Kreienbrock Erika Baum 《Zeitschrift fur Gesundheitswissenschaften》1994,2(4):324-333
Objective
To estimate the impact of different systems of family practitioners’ payment on process of care: fee-for-service vs. capitation.Design
Cross sectional international survey using cardiovascular prevention as an indicator of the quality of care.Setting
Family physicians’ practices in Germany (fee-for-service) and the UK (capitation).Subjects
778 patients attending for consultation regardless of morbidity or risk factor status.Main outcome measures
Intervals since last consultation, since last BP-measurement, prevalence of known hypertension.Results
There is a higher overall level of activity under FFS, but under capitation FPs seem to concentrate their efforts on the more severely ill or at risk. This would explain that under different systems of remuneraton the quality of care (outcome) is usually similar.Conclusions
In areas of uncertainty FFS seems to stimulate activity or intervention, whereas under capitation FPs are rather reluctant to engage in procedures or interventions that are not sufficiently evaluated. Under prepaid remuneration FPs adjust in a way that the quality of care does not suffer. 相似文献34.
The parasites of ten fish species, including four Gobiidae, three Gasterosteidae, two Syngnathidae, and one Zoarcidae from the Salzhaff region, Northwest Mecklenburg, Baltic Sea, were investigated in 1995 and 1996. As many as 36 parasite species, represented by diverse groups of helminths and protozoans as well as annelids and copepods, are found during 4 seasons in these hosts. By far the most abundant group is represented by digeneans, comprising 15 species, followed by 7 cestodans and 6 nematodes. With regard to component communities, 8 host-parasite combinations are core and secondary species with more than 40% prevalence in which generalists such as the digeneans Podocotyle atomon and Cryptocotyle concavum (in 3 hosts). C. lingua, Diplostomum spathaceum, and Acanthostomum balthicum, and the nematode Hysterothylacium are involved. Also, specialists such as Aphalloides timmi in Pomatoschistus microps as well as Magnibursatus caudofilamentosa and Thersitina gasterostei in Gasterosteus aculeatus attain high levels of prevalence. A comparison of different investigations reveals greater prevalence of allogenic and autogenic parasite species with 3 host cycles in the Rerik-Riff (free Baltic) and higher levels of prevalence of autogenic parasite species with 1 or 2 host cycles in the entire Salzhaff. The component communities of gobies from Dahmeshöved, Lübeck Bight, attain generally lower degrees of prevalence than those of the Salzhaff region. The infracommunities consist mostly of 1–3 parasite species per host specimen; this value is surpassed on occasion in P. microps (maximum 7 species) and in G. aculeatus (maximum 9 species, which may compete for 5 microhabitats in a host specimen). In this context the theory of empty niches propagated by some parasitologists is critically discussed and substituted by the assumption of variable niche widths. The seasonality of the more abundant parasites is either unclear – as in the case of C. concavum– or evident – as in the case of P. atomon, which prevail in early spring and summer, or A. timmi, which dominate in late summer, as do M. caudofilamentosa, which is absent in spring. The main causes of the infestation of fish hosts may be their ages and the availability of parasites due to the presence of intermediate hosts. 相似文献
35.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献
36.
Sarah E. Coupland Lothar Krause Friedrich Hoffmann 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(2):116-124
Background: The presence of Ia-positive cells (MHC class II equivalent) has been previously reported in the iris and choroid of various species. They have been reported to have both round and dendritic morphologies; the latter may represent classic dendritic cells, potent antigen-presenting cells (APCs). It is possible that the dendritic-like cells play a important role in (auto)immune processes of uveal and other ocular tissues. Using the flat or whole mount technique, the distribution of Ia-positive cells in the rat iris and choroid was investigated following penetrating Keratoplasty (PKP) and following treatment with cyclosporin A (CsA). Methods: Lewis (LW) rats received corneal buttons from Lewis-Brown Norway (LW-BN) donors and were randomly assigned to the following groups: (i) operated, untreated (n=24); (ii) operated, CsA-treated (10 mg/kg i.m.;n=22). Controls were groups (iii) normal LW rats (n=13); (iv) unopcrated, CsA-treated (16 days' treatment;n=8); (v) anterior perforation of the anterior chamber (n=3); (vi) eight corneal sutures only (n=4); (vii) syngeneic operated (LW to LW;n=4). Animals of groups (i) and (ii) were killed on the 5th, 9th and 13th postoperative days and on appearance of the corneal rejection (group i, day 13; group ii, day 16). Both eyes were enucleated, immediately fixed, and iris-choroid flat mounts were examined for Ia-positive cells using APAAP immunohistochemistry. Results: In the normal Lewis rat iris, scattered Ia-positive cells of both nondendritic and dendritic morphology were observed. CsA treatment in the unoperated rat did not result in a significant decrease in the percentage of dendritic cells in the iris or choroid. Anterior chamber perforation, the placement of sutures in the cornea and syngeneic PKP resulted in a moderate increase in iris Ia-positive cells. Allogeneic transplantation resulted in a large increase in both types of Ia-positive cells, particularly on day 13 with corneal rejection. In group ii, an initial decrease in Ia-positive cells until day 13 was observed; upon rejection (day 16), the histological picture was similar to that of untreated animals. Alterations in the operated choroid were also apparent following CsA treatment. Conclusion: Corneal transplantation in the Lewis rat results in an increase in Ia-positive cells in the iris; CsA therapy can delay but not prevent this reaction. Changes in choroidal Ia-positive cells following PKP were not apparent, their numbers being affected only by CsA treatment following grafting. 相似文献
37.
Purpose
We present a time and labor saving embedding technique for a full-thickness bowel flap tube used as a continent outlet.Materials and Methods
In 17 patients the bowel flap tube was extramurally embedded instead of being submucosally tunneled. The reservoir was attached to the abdominal wall to reinforce the continence mechanism and prevent the tunnel from opening.Results
All 17 patients are completely continent and 14 of 16 evacuate urine easily with a 14F catheter. Due to recurrent stomal stenosis 1 patient with severe diabetes has undergone incontinent diversion.Conclusions
Our described tunneling procedure for the full-thickness bowel flap tube is easy to perform and provides excellent continence. 相似文献38.
Long-term functional results and quality of life after ileal pouch-anal anastomosis and cholecystectomy 总被引:5,自引:0,他引:5
Lothar W. Köhler M.D. John H. Pemberton M.D. David O. Hodge M.S. Alan R. Zinsmeister Ph.D. Keith A. Kelly M.D. 《World journal of surgery》1992,16(6):1126-1131
Among 971 patients with chronic ulcerative colitis who underwent ilealpouch anal anastomosis during an 8-year period from January, 1982 to December 1989, 30 patients were randomly selected from each year (total = 240 patients) for an assessment of their long-term functional results and quality of life as of 1990. Patients undergoing cholecystectomy during each of the same years served as controls (20 patients/year, total = 160 patients). All 400 patients completed a written questionnaire that measured bowel habits, overall quality of life, general health, and performance in sports/recreation, travel, sex life, family relationship, occupational work, social activities, and household activities. Ileo-anal patients had more frequent stools (median, 6 stools/day) and more fecal spotting (68% of patients had episodes) than cholecystectomy patients (median, 1 stool/day, 13% had episodes,p<0.05). In spite of the altered bowel habits, 90% of ileo-anal patients had an excellent overall quality of life, 76% enjoyed good health, and 91% had good performance scores in the areas examined. In fact, quality of life and performance were similar among ileo-anal patients and cholecystectomy patients. Moreover, quality of life and bowel habits remained steady in both groups of patients during the 8-year follow-up. In conclusion, functional results were satisfactory and quality of life was excellent after ileal pouch-anal anastomosis; neither deteriorated as patients aged over an 8-year period after operation.
Resumen Se conformó al azar un grupo de 240 pacientes, seleccionando anualmente 30 entre un total de 971 pacientes con colitis ulcerativa crónica que fueron sometidos a resección y recostrucción con anastomosis ileo-bolsa anal en un período de ocho años entre enero de 1982 y diciembre de 1983, con el propósito de valorar los resultados a largo plazo y la calidad de vida en el año 1990. Los pacientes sometidos a colecistectomía en el mismo período sirvieron como controles (20 pacientes año, total = 160 pacientes). Todos los 400 pacientes diligenciaron un cuestionario escrito sobre hábito intestinal, la calidad global de la vida, estado general de salud, rendimiento en cuanto a deportes/recreación, viajes, vida sexual, relación familiar, trabajo ocupacional, actividades sociales y actividades domésticas. Los pacientes con la anastomosis ileoanal presentaron mayor número de defecaciones (6 diarias, medio) y más manchado fecal (68% de los pacientes presentaron tales epísodios) que los pacientes colecistectomizados (1 defecación diaria, medio; 13% presentaron tales epísodios,p<0.05). A pesar de la alteración en el hábito intestinal, el 90% de los pacientes manifestó una excelente calidad global de la vida, el 76% gozó de buena salud y el 91% tuvo un buen rendimiento en las áreas investigadas. En efecto, la calidad de la vida y el rendimiento aparecieron similares entre los pacientes ileoanales y los colecistectomizados; por lo demás, la calidad de la vida y los hábitos intestinales se mantuvieron estables en ambos grupos en el curso de los ocho años de seguimiento. En conclusión, los resultados funcionales fueron satisfactorios y la calidad de la vida fue excelente luego de una anastomosis ileo-bolsa anal, y ésto no pareció deteriorarse con el avance de la edad en el período de seguimiento de ocho años.
Résumé Parmi 971 patients ayant une rectocolite ulcéreuse chronique et ayant eu une anastomose iléo-anale pendant la période de 8 ans compris entre Janvier 1982 et Décembre 1989, 30 patients ont été sélectionés au hasard chaque année (n=240 patients au total) pour évaluer leur résultats fonctionnels à distance et leur qualité de vie en 1990. Des patients ayant eu une cholécystectomie pendant cette même période de temps ont servi de contrôles (n=20 patients/an pour un total de 160 patients). Les 400 patients inclus dans cette étude ont rempli un questionnaire par écrit qui comportait le nombre et le type des selles, la qualité de vie, l'état général, et l'activité (voyages, vie sexuelle, relations familiales, travail, vie sociale, et vie à la maison). Les patients ayant eu anastomose iléoanale avaient plus de selles (mediane = 6 selles/jour) et plus de pertes fécales (68% des patients avaient des taches fécales) que les patients ayant eu une cholécystectomie (médiane = 1 selle/jour et 13% de patients ayant des taches;p<0.05). Malgré des modification dans les habitudes pour aller à selle, 90% des patients ayant une anastomose iléoanale estimaient avoir une qualité de vie excellente, 76% s'estimaient en bonne santé et 91% avaient de bons scores dans les activités énumérées ci-dessus. La qualité de vie et les scores étaient identiques aux patients cholécystectomisés. La qualité de vie et les selles sont restées stables dans les deux groupes de patients. En conclusion, les résultats fonctionnels étaient satisfaisants et la qualité de vie excellente après une anastomsose iléoanale; elles ne se sont pas détérioriées pendant la période de suivi de huit ans.相似文献
39.
Occupational medicine for one and all 总被引:1,自引:0,他引:1
R S Schilling 《British journal of industrial medicine》1991,48(7):445-450
In the 1930s in Britain, industrial medicine was a clinical discipline, the main purposes of which were to diagnose disability in applicants for work, to identify industrial disease in the dangerous trades, and to provide first aid treatment for those injured or taken sick in the workplace. Following rapid developments in epidemiology and occupational hygiene and with more emphasis on "group health" and less on "individual care", occupational medicine has tended to become less of a clinical discipline; yet clinical skills are needed to assess fitness for work, to identify adverse effects of work, and to undertake consultations on a variety of health problems. Although care of the individual worker is a major task, an occupational health service has a responsibility for the health of the workforce as a whole, using epidemiology to plan and administer health care, to identify and control work related disorders, and to promote health by identifying positive factors in the organisation that induce a sense of well being; and by health screening and education programmes. Academic occupational health should not lose its identity as a clinical discipline in any merger with environmental health. Medical skills are needed to assess fitness for work and to identify human responses to adverse factors in the environment and to evaluate control measures. 相似文献
40.
O'Brien TE Ashford TP Vetter TG Wilson MJ Schilling BA 《Hospital formulary》1977,12(5):315, 319-315, 320