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Chronic myeloproliferative disorders: prognostic importance of new working classification 总被引:1,自引:1,他引:0 下载免费PDF全文
Variants of chronic myeloproliferative disorders (CMPD) were compared according to their clinical features and classified by bone marrow biopsy appearances. Subsequently, this classification was further evaluated using survival data and histological variables from iliac crest biopsy specimens of an additional 1391 patients, making a total of 2241 patients available for analysis of outcome. The patients were grouped again into three main classes: "typical"; "variant"; and "transformed". "Typical" comprised the "classic" groups. "Variant" included the less uniform myeloproliferative syndromes, distinguished also by more variable clinical features, a different prognosis, and a greater tendency to fibrotic and blastic transformation. "Transformed" defined the end stages of both "typical" and "variant" types. Ten subgroups were distinguished by different histology and prognosis. Particular prognostic importance was assigned to atypia and immaturity of haemopoiesis, predominance of individual haemopoietic cell line, number and anomalies of megakaryocytes and progressive fibrosis. It is suggested that the proposed subclassification would be helpful for studies of epidemiology and therapeutic trials by allowing more homogeneous groups to be recognised. 相似文献
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Aravind Krishnan Joshua Hsu Jinny S. Ha Stephen R. Broderick Pali D. Shah Robert SD. Higgins Christian A. Merlo Errol L. Bush 《American journal of surgery》2021,221(4):731-736
PurposeWe aimed to assess the prognostic value of Neutrophil to Lymphocyte Ratio (NLR) on long-term outcomes and graft dysfunction after lung transplantation.MethodsWe retrospectively reviewed all patients receiving a lung transplant at our institution from 2011 to 2014. The primary exposure was elevated NLR at the time of transplant, defined by NLR>4. The primary outcomes were graft failure and three-year all-cause mortality. Multivariate logistic regression and Kaplan-Meier survival analysis were used to analyze outcomes.Results95 patients were included. 40 patients (42%) had an elevated NLR. Elevated NLR was associated with graft failure (OR: 4.7 [1.2–18.8], p = 0.02), and three-year mortality (OR: 5.4 [1.3–23.2], p = 0.03) on multivariate logistic regression. Patients with elevated NLR demonstrated significantly lower survival on Kaplan-Meier analysis (50% versus 74%, p = 0.02). The c-statistic for our multivariate model was 0.91.ConclusionElevated neutrophil to lymphocyte ratio is associated with poor long-term survival and graft failure after lung transplantation. 相似文献
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GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
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Non-typhoid Salmonella gastroenteritis 总被引:2,自引:0,他引:2
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BACKGROUND: To evaluate debt and other factors that help formulate the career paths of future surgical and primary care physicians, a survey was undertaken. METHODS: Surgical specialty (SS) and primary care (PC) residents were surveyed regarding demographics, factors influencing choice of specialty, methods of financing education, debt characteristics, and outlooks regarding future earnings and practice characteristics. RESULTS: The clinical years of medical school and personalities of specialists and residents were important factors in career choices for both PC and SS. The length of residency, desirable lifestyle, and working hours were all more important to PC residents. Surgeons found intellectual challenge and procedure-based practice of greater importance. Although not highly regarded by either group, scholarship obligation and student loans had a significantly greater impact on specialty choice and practice plans for PC residents. At the completion of training, 55% of SS and 28% of PC residents anticipate owing more than $100,000. Debt was especially significant in specialty choice and practice plans for PC residents with debt over $100,000. CONCLUSION: Surgical residents are less concerned about personal sacrifices in their quest to become surgeons. It appears state funded scholarships are successful in attracting students to primary care. Both SS and PC residents have significant debt, although, SS residents have greater financial debt than primary care residents. However, the anticipation of indebtedness was a more significant factor in determination of career path for PC. 相似文献
7.
Woodworth PA McBoyle MF Helmer SD Beamer RL 《The American surgeon》2000,66(5):444-50; discussion 450-1
The pathophysiology of seroma formation has yet to be determined. Therefore, the present study was undertaken to calculate the incidence of postoperative seromas after definitive breast cancer operations utilizing electrocautery dissection. Additionally, we attempted to identify risk factors associated with seroma development and to examine seroma formation in relation to operative procedure. A retrospective review of 252 breast cancer operations was undertaken. Patients were subdivided by operative procedure: modified radical mastectomy (MRM; n = 148), breast preservation with axillary node dissection (n = 64), or MRM with immediate reconstruction (n = 40). Electrocautery was used in development of skin flaps. Seromas developed in 39 of the 252 operations for an incidence of 15.5 per cent. Seroma formation was significantly lower in those patients receiving MRM with immediate reconstruction than in those receiving MRM (2.5% vs 19.6%; P = 0.009) and tended to be lower than for patients receiving breast preservation with axillary node dissection (14.06%; P = 0.052). Neoadjuvant chemotherapy was performed in 18 patients, of whom 6 developed seromas (P = 0.030). The incidence of postoperative seromas was low despite the use of electrocautery. An association of postoperative seromas with neoadjuvant chemotherapy was noted. Additionally, it appears that immediate reconstruction may reduce the incidence of postoperative seromas, presumably by filling the dead space in the chest wall. 相似文献
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Mode of action of iron (III) chelators as antimalarials: II. Evidence for differential effects on parasite iron-dependent nucleic acid synthesis 总被引:1,自引:0,他引:1
Iron chelation treatment of red blood cells infected with Plasmodium falciparum selectively intervenes with iron-dependent metabolism of malaria parasites and inhibits their development. Highly permeant hydroxamate iron chelator RSFileum2 affects all parasite stages when cultures are continuously exposed to drug, but affects primarily ring stages when assessed for irreversible effects, ie, sustained inhibition remaining after drug removal. On the other hand, the hydrophilic and poorly permeant desferrioxamine (DFO) affects primarily trophozoite/schizont stages when tested either in the continuous mode or irreversible mode. Unlike parasites, mammalian cells subjected to similar drug treatment show complete growth recovery once drugs are removed. Our studies indicate that parasites display a limited capacity to recover from intracellular iron depletion evoked by iron chelators. Based on these findings we provide a working model in which the irreversible effects of RSFs on rings are explained by the absence of pathways for iron acquisition/utilization by early forms of parasites. Trophozoite/schizonts can partially recover from RSFileum2 treatments, but show no DNA synthesis following DFO treatment even after drug removal and iron replenishment by permeant iron carriers. At trophozoite stage, the parasite uses a limited pathway for refurnishing its iron-containing enzymes, thus overcoming iron deprivation caused by permeant RSFileum2, but not by DFO because this latter drug is not easily removable from parasites. Their DNA synthesis is blocked by the hydroxamate iron chelators probably by affecting synthesis of ribonucleotide reductase (RNRase). Presumably in parasites, prolonged repression of the enzyme leads also to irreversible loss of activity. The action profiles of RSFileum2 and DFO presented in this study have implications for improved chemotherapeutic performance by combined drug treatment and future drug design based on specific intervention at parasite DNA synthesis. 相似文献