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An analysis of clinical and laboratory features of acute lymphocytic leukemias with emphasis on 35 children with pre-B leukemia 总被引:2,自引:0,他引:2
L B Vogler W M Crist A M Sarrif D J Pullen A A Bartolucci J M Falletta B Dowell G B Humphrey R Blackstock J van Eys R S Metzgar M D Cooper 《Blood》1981,58(1):135-140
In 35 of 191 patients with acute lymphocytic leukemia (ALL) malignant cells were similar in phenotype to B-lymphocyte precursors. Both these patients' lymphoblasts and normal pre-B-cells contain cytoplasmic immunoglobulin (Ig) mu heavy chains, but have no surface Ig. In patients with pre-B leukemias, lymphoblasts containing cytoplasmic mu chains alone were often accompanied by cells of identical morphology that expressed no Ig and less frequently by lymphoblasts bearing scant amounts of surface mu. This spectrum of cellular Ig expression suggests that "null," pre-B, and intermediate pre-B/B ALLs represent closely related malignancies with complete or partial arrests at different stages of maturation. When pre-B, B, T, and "null" cell categories of ALL were compared for 22 different clinical and laboratory features, including remission rate and short-term remission duration, no statistical differences were observed between the pre-B and "null" groups. These early results suggest that pre-B-cell leukemias represents a relatively good prognostic subclass of ALL, do not require more intensive treatment than that proven to be effective for "null" cell ALL, and should be distinguished from the less common, but more clinically aggressive, B-cell subclass of ALL. Longer follow-up will be required to confirm these preliminary conclusions. 相似文献
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Protected areas facilitate species' range expansions 总被引:1,自引:0,他引:1
CD Thomas PK Gillingham RB Bradbury DB Roy BJ Anderson JM Baxter NA Bourn HQ Crick RA Findon R Fox JA Hodgson AR Holt MD Morecroft NJ O'Hanlon TH Oliver JW Pearce-Higgins DA Procter JA Thomas KJ Walker CA Walmsley RJ Wilson JK Hill 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(35):14063-14068
The benefits of protected areas (PAs) for biodiversity have been questioned in the context of climate change because PAs are static, whereas the distributions of species are dynamic. Current PAs may, however, continue to be important if they provide suitable locations for species to colonize at their leading-edge range boundaries, thereby enabling spread into new regions. Here, we present an empirical assessment of the role of PAs as targets for colonization during recent range expansions. Records from intensive surveys revealed that seven bird and butterfly species have colonized PAs 4.2 (median) times more frequently than expected from the availability of PAs in the landscapes colonized. Records of an additional 256 invertebrate species with less-intensive surveys supported these findings and showed that 98% of species are disproportionately associated with PAs in newly colonized parts of their ranges. Although colonizing species favor PAs in general, species vary greatly in their reliance on PAs, reflecting differences in the dependence of individual species on particular habitats and other conditions that are available only in PAs. These findings highlight the importance of current PAs for facilitating range expansions and show that a small subset of the landscape receives a high proportion of colonizations by range-expanding species. 相似文献
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Qaseem A Humphrey LL Sweet DE Starkey M Shekelle P;Clinical Guidelines Committee of the American College of Physicians 《Annals of internal medicine》2012,156(3):218-231
DESCRIPTION: The American College of Physicians (ACP) developed this guideline to present the evidence and provide clinical recommendations on the comparative effectiveness and safety of type 2 diabetes medications. METHODS: This guideline is based on a systematic evidence review evaluating literature published on this topic from 1966 through April 2010 that was identified by using MEDLINE (updated through December 2010), EMBASE, and the Cochrane Central Register of Controlled Trials. Searches were limited to English-language publications. The clinical outcomes evaluated for this guideline included all-cause mortality, cardiovascular morbidity and mortality, cerebrovascular morbidity, neuropathy, nephropathy, and retinopathy. This guideline grades the evidence and recommendations by using the American College of Physicians clinical practice guidelines grading system. RECOMMENDATION 1: ACP recommends that clinicians add oral pharmacologic therapy in patients diagnosed with type 2 diabetes when lifestyle modifications, including diet, exercise, and weight loss, have failed to adequately improve hyperglycemia (Grade: strong recommendation; high-quality evidence). RECOMMENDATION 2: ACP recommends that clinicians prescribe monotherapy with metformin for initial pharmacologic therapy to treat most patients with type 2 diabetes (Grade: strong recommendation; high-quality evidence). RECOMMENDATION 3: ACP recommends that clinicians add a second agent to metformin to treat patients with persistent hyperglycemia when lifestyle modifications and monotherapy with metformin fail to control hyperglycemia (Grade: strong recommendation; high-quality evidence). 相似文献
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Qaseem A Denberg TD Hopkins RH Humphrey LL Levine J Sweet DE Shekelle P;Clinical Guidelines Committee of the American College of Physicians 《Annals of internal medicine》2012,156(5):378-386
DESCRIPTION: Colorectal cancer is the second leading cause of cancer-related deaths for men and women in the United States. The American College of Physicians (ACP) developed this guidance statement for clinicians by assessing the current guidelines developed by other organizations on screening for colorectal cancer. When multiple guidelines are available on a topic or when existing guidelines conflict, ACP believes that it is more valuable to provide clinicians with a rigorous review of the available guidelines rather than develop a new guideline on the same topic. METHODS: The authors searched the National Guideline Clearinghouse to identify guidelines developed in the United States. Four guidelines met the inclusion criteria: a joint guideline developed by the American Cancer Society, the U.S. Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology and individual guidelines developed by the Institute for Clinical Systems Improvement, the U.S. Preventive Services Task Force, and the American College of Radiology. GUIDANCE STATEMENT 1: ACP recommends that clinicians perform individualized assessment of risk for colorectal cancer in all adults. GUIDANCE STATEMENT 2: ACP recommends that clinicians screen for colorectal cancer in average-risk adults starting at the age of 50 years and in high-risk adults starting at the age of 40 years or 10 years younger than the age at which the youngest affected relative was diagnosed with colorectal cancer. GUIDANCE STATEMENT 3: ACP recommends using a stool-based test, flexible sigmoidoscopy, or optical colonoscopy as a screening test in patients who are at average risk. ACP recommends using optical colonoscopy as a screening test in patients who are at high risk. Clinicians should select the test based on the benefits and harms of the screening test, availability of the screening test, and patient preferences. GUIDANCE STATEMENT 4: ACP recommends that clinicians stop screening for colorectal cancer in adults over the age of 75 years or in adults with a life expectancy of less than 10 years. 相似文献
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Qaseem A Alguire P Dallas P Feinberg LE Fitzgerald FT Horwitch C Humphrey L LeBlond R Moyer D Wiese JG Weinberger S 《Annals of internal medicine》2012,156(2):147-149
Unsustainable rising health care costs in the United States have made reducing costs while maintaining high-quality health care a national priority. The overuse of some screening and diagnostic tests is an important component of unnecessary health care costs. More judicious use of such tests will improve quality and reflect responsible awareness of costs. Efforts to control expenditures should focus not only on benefits, harms, and costs but on the value of diagnostic tests-meaning an assessment of whether a test provides health benefits that are worth its costs or harms. To begin to identify ways that practicing clinicians can contribute to the delivery of high-value, cost-conscious health care, the American College of Physicians convened a workgroup of physicians to identify, using a consensus-based process, common clinical situations in which screening and diagnostic tests are used in ways that do not reflect high-value care. The intent of this exercise is to promote thoughtful discussions about these tests and other health care interventions to promote high-value, cost-conscious care. 相似文献
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