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排序方式: 共有3197条查询结果,搜索用时 15 毫秒
61.
Dallo FJ Weller SC 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(18):10574-10579
Screening guidelines proposed by the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus have been endorsed by several medical societies. However, one-third of cases are undiagnosed, and complications at the time of diagnosis indicate that disease may have been present for several years before diagnosis. This study evaluates the effectiveness of the guidelines for detecting new cases of diabetes mellitus. By using a cross-sectional, representative sample of the United States (National Health and Nutritional Examination Survey, NHANES III), the guidelines are tested on adults, 20 years and older without a prior diagnosis of diabetes. Individuals are classified as nondiabetics (n = 6,241) or as having undiagnosed diabetes (n = 274) based on their blood glucose. Screening when one risk factor is present, as stated in the guidelines, has a true-positive rate of 100% and would require that 83% of the population be tested. Screening when two risk factors are present is more efficient, with a comparable true-positive rate (98%), but requires that only 59% of the population be tested. A notable finding is the earlier age of onset among minorities, which may be associated with other health disparities. Because diabetes occurs at younger ages in minorities, screening whites who are > or =40 and minorities > or =30 years of age has a high true-positive rate (95%) and also reduces testing (60%). The screening guidelines would be effective, if followed, and would essentially eliminate undiagnosed cases of diabetes. 相似文献
62.
CL Sanchez CS Biskup S Herpertz TJ Gaber CM Kuhn SH Hood FD Zepf 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(10)
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. 相似文献
63.
Roy O. Weller Cheryl A. Hawkes Raj N. Kalaria David J. Werring Roxana O. Carare 《Brain pathology (Zurich, Switzerland)》2015,25(1):63-78
White matter abnormalities on magnetic resonance imaging (MRI) are associated with dementia and include white matter hyperintensities (WMH; also termed leukoaraiosis) and visible perivascular spaces (PVS). We review the potential role of impaired drainage of interstitial fluid in the pathogenesis of WMH and PVS. Whereas the volume of extracellular space in the grey matter is tightly controlled, fluid accumulates and expands the extracellular spaces of the white matter in acute hydrocephalus, vasogenic edema and WMH. Although there are no conventional lymphatic vessels in the brain, there is very effective lymphatic drainage for fluid and solutes along restricted pathways in the basement membranes of cerebral capillaries and arteries in young individuals. Lymphatic drainage of the brain is impaired with age and in association with apolipoprotein E ε4, risk factors for Alzheimer's disease and cerebral amyloid angiopathy (CAA). Deposition of proteins in the lymphatic drainage pathways in the walls of cerebral arteries with age is recognized as protein elimination failure angiopathy (PEFA), as in CAA and cerebral autosomal dominant arteriopathy and leukoencephalopathy (CADASIL). Facilitating perivascular lymphatic drainage from the aging brain may play a significant role in the prevention of CAA, WMH and Alzheimer's disease and may enhance the efficacy of immunotherapy for Alzheimer's disease. 相似文献
64.
2-Methoxyestradiol overcomes drug resistance in multiple myeloma cells 总被引:13,自引:11,他引:13
Chauhan D Catley L Hideshima T Li G Leblanc R Gupta D Sattler M Richardson P Schlossman RL Podar K Weller E Munshi N Anderson KC 《Blood》2002,100(6):2187-2194
2-Methoxyestradiol (2ME2) an estrogen derivative, induces growth arrest and apoptosis in leukemic cells and is also antiangiogenic. In this study, we demonstrate that 2ME2 inhibits growth and induces apoptosis in multiple myeloma (MM) cell lines and patient cells. Significantly, 2ME2 also inhibits growth and induces apoptosis in MM cells resistant to conventional therapies including melphalan (LR-5), doxorubicin (Dox-40 and Dox-6), and dexamethasone (MM.1R). In contrast to its effects on MM cells, 2ME2 does not reduce the survival of normal peripheral blood lymphocytes. Moreover, 2ME2 enhances Dex-induced apoptosis, and its effect is not blocked by interleukin-6 (IL-6). We next examined the effect of 2ME2 on MM cells in the bone marrow (BM) milieu. 2ME2 decreases survival of BM stromal cells (BMSCs), as well as secretion of vascular endothelial growth factor (VEGF), and IL-6 triggered by the adhesion of MM cells to BMSCs. We show that apoptosis induced by 2ME2 is mediated by the release of mitochondrial cytochrome-c (cyto-c) and Smac, followed by the activation of caspases-8, -9, and -3. Finally, 2ME2 inhibits MM cell growth, prolongs survival, and decreases angiogenesis in a murine model. These studies, therefore, demonstrate that 2ME2 mediates anti-MM activity directly on MM cells and in the BM microenvironment. They provide a framework for the use of 2ME2, either alone or in combination with Dex, to overcome drug resistance and to improve outcome in MM. 相似文献
65.
Clinical, biochemical, serological, histological and ultrastructural features of liver disease in drug abusers 下载免费PDF全文
I V Weller D Cohn A Sierralta M Mitcheson M G Ross L Montano P Scheuer H C Thomas 《Gut》1984,25(4):417-423
Heroin abusers are frequently found to have abnormal liver function tests and hepatic histology. Hepatitis viruses A, B, and NANB, other drugs or drug contaminants and excessive alcohol consumption are factors thought to contribute. One hundred and sixteen heroin abusers attending a London treatment centre were studied. Sixty two (53%) had a raised aspartate transaminase. This was not explained by current infection with hepatitis A and B, cytomegalo or Epstein-Barr viruses, excessive alcohol consumption (greater than 80 g/day) or concomitant drug taking. Abnormal liver function tests were as frequent in those with markers of current or past HBV infection as those without and there was evidence that both HBV infection and the cause of the abnormal liver function tests were acquired in the first few years of intravenous drug abuse. Liver biopsies from eight patients showed chronic hepatitis with a mild lobular and portal inflammatory infiltrate, fatty change and prominent sinusoidal cells. Electron microscopy showed cytoplasmic trilaminar tubular structures and dense fused membranes in dilated endoplasmic reticulum. These clinical, biochemical, serological, and histological features would suggest a major role for NANB virus infection in the aetiology of hepatitis in heroin abusers. 相似文献
66.
Lefkowitz JB DeBoom T Weller A Clarke S Lavrinets D 《American journal of hematology》2000,63(3):149-155
A new fibrinogen variant was discovered as a result of discrepancies found in routine laboratory screening. The patient, a healthy 37-year-old woman, had a mild bleeding history. Initial coagulation studies on the patient revealed a prolonged prothrombin time (PT) and a normal activated partial thromboplastin time (APTT). Further investigation on the patient and her mother demonstrated both had a PT with no end point using an optical detection method (ACL3000+) and a normal PT using an electromechanical detection method (ST4 Clot Detection System). The APTT for both the patient and her mother were essentially normal with both optical and mechanical detection methods. The patient and her mother also had markedly prolonged thrombin time and reptilase time results on the ACL3000+, but they were normal on the ST4. Coagulation test results on the patient's father were all normal. We believe the fibrinogen defect in this family may affect fibrin polymerization only enough to effect light scatter interpretation, while there is enough polymerization to increase plasma viscosity and yield an end point using an electromechanical analyzer. This report should alert pathologists and clinicians to possible discrepancies between mechanical and spectrophotometric clot testing methods. 相似文献
67.
68.
Stoecklein Veit Michael Kellert Lars Patzig Maximilian Küpper Clemens Giese Armin Ruf Viktoria Weller Jonathan Kreth Friedrich-Wilhelm Schöberl Florian 《Journal of neurology》2021,268(1):367-376
Journal of Neurology - To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous... 相似文献
69.
Purified populations of natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID). SCID spleen cells were cultured and activated with recombinant human interleukin-2 (rhIL- 2) in vitro. The activated NK cells were then transferred with syngeneic BALB/c bone marrow cells (BMC) and rhIL-2 into lethally irradiated syngeneic recipients to determine their effect on long-term hematopoietic reconstitution. On analysis, the transfer of rhIL-2- activated NK cells along with BMC resulted in significant increases in splenic and BM hematopoietic progenitor cells when compared with those for mice not receiving NK cells. Histologic and flow cytometric analysis showed a marked increase in granulocytic and megakaryocytic lineage cells present in the spleens of the mice receiving activated NK cells. Analysis of the peripheral blood indicated that the transfer of activated NK cells with BMC also significantly improved platelet and total white blood cell counts, with increases in segmented neutrophils. Erythroid recovery was not affected. Finally, lethally irradiated mice receiving activated NK cells and rhIL-2 along with limiting numbers of syngeneic BMC showed a marked increase in survival rate. These results show that the use of populations enriched for activated NK cells after syngeneic BM transplantation (BMT) has a profound enhancing effect on engraftment primarily affecting megakaryocytic and granulocytic cell reconstitution. Therefore, the transfer of activated NK cells and rhIL- 2 may be of clinical use to promote hematopoietic reconstitution after BMT. 相似文献
70.
Ng VL; Hurt MH; Fein CL; Khayam-Bashi F; Marsh J; Nunes WM; McPhaul LW; Feigal E; Nelson P; Herndier BG 《Blood》1994,83(4):1067-1078
Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis. 相似文献