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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
W. de Riese E. B. Walker C. de Riese T. M. Ulbright W. N. Crabtree J. Messemer J. A. Jones A. Hinkel R. S. Foster J. P. Donohue T. Senge 《Urological research》1994,22(4):213-220
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only. 相似文献
32.
Flexible Sigmoidoscopy Screening in an Industrial Setting 总被引:1,自引:0,他引:1
Benjamin Krevsky M.D. M.P.H. F.A.C.G. Tomasz Niewiarowski M.D. Rita League R.N. Harold Herman M.D. Lisa Matz Robert S. Fisher M.D. F.A.C.G. 《The American journal of gastroenterology》1992,87(12):1759-1762
Little is known about the yield of colorectal cancer screening programs in an industrial setting. We therefore established a flexible sigmoidoscopy screening program at a chemical manufacturing plant and offered testing to all employees over the age of 40. After a Fleet enema preparation had been administered, a digital rectal examination and sigmoidoscopy were performed on each volunteer worker in the medical office of the plant. The plant had an average census of about 650 workers; 202 were screened during a 2-yr period. The mean (+/- SEM) age of participants was 52 +/- 0.4. Sixty-four employees had polyps (31.7%); data on follow-up colonoscopy were available in 69%. Colonoscopy revealed adenomatous polyps in 23 workers (53.5%), hyperplastic polyps in 10 (23%), and no evidence of neoplasia in 10 (23%). Seven workers did not arrange for follow-up colonoscopy and 12 individuals could not be contacted. No cancers were detected. In the 40- to 50-yr age group, polyps were detected in 19.5% of employees (25% adenomatous). Incidental findings were common, and included prostatic nodules, hemorrhoids, diverticulosis, and proctitis, among others. We conclude that screening sigmoidoscopy can be conveniently and economically performed at the workplace, with a high yield and good worker acceptance. The high yield suggests a possible association between polyp formation and work in a chemical plant. The finding of adenomatous polyps in the younger patients suggests that the threshold for flexible sigmoidoscopy at age 50 needs to be reassessed. 相似文献
33.
Chemotherapy of bilateral acoustic neuromas 总被引:2,自引:0,他引:2
In patients with bilateral acoustic neuromas, it is not unusual for the tumors to be of unequal size. At the time of the first examination, the smaller tumor may have already destroyed the hearing, while the ear with residual hearing may harbor a large acoustic neuroma. The remaining hearing is then at great risk if surgical removal of the tumor is attempted. Chemotherapy of bilateral acoustic neuromas is here presented as a possible alternative to surgery in those patients whose prognosis for conservation of hearing is poor. 相似文献
34.
R. Parker Ward MD Mouaz H. Al-Mallah MD Gabriel B. Grossman MD PhD Christopher L. Hansen MD Robert C. Hendel MD Todd C. Kerwin MD Benjamin D. McCallister Jr MD Rupa Mehta MD Donna M. Polk MD MPH Peter L. Tilkemeier MD Aseem Vashist MD Kim Allan Williams MD David G. Wolinsky MD Edward P. Ficaro PhD 《Journal of nuclear cardiology》2007,14(6):911-e38
35.
R. Parker Ward Mouaz H. Al-Mallah Gabriel B. Grossman Christopher L. Hansen Robert C. Hendel Todd C. Kerwin Benjamin D. McCallister Rupa Mehta Donna M. Polk Peter L. Tilkemeier Aseem Vashist Kim Allan Williams David G. Wolinsky Edward P. Ficaro 《Journal of nuclear cardiology》2007,14(6):e26-e38
Conclusion The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the
AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of
indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list,
suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high
risk.”. An objective review of existing indications focused on only those indications that had significant variability among
the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends
that the grades for 6 indications be re-evaluated.
The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC
recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role
in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and
ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed
Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards.
Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee.
Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20. 相似文献
36.
37.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
38.
Use of antibiotic and analgesic drugs during lactation. 总被引:2,自引:0,他引:2
Benjamin Bar-Oz Mordechai Bulkowstein Lilach Benyamini Revital Greenberg Ingrid Soriano Deena Zimmerman Oxana Bortnik Matitiahu Berkovitch 《Drug safety》2003,26(13):925-935
During lactation, multiple situations can arise that require maternal pharmacological treatment. Because of the many health advantages of human milk to infants, breast feeding should be interrupted only when the needed drug might be harmful to the nursing child and exposure via the breast milk will be sufficient to pose a risk. Since the majority of drugs have not been shown to cause adverse effects when used during lactation, and even temporary interruption of breast feeding can be difficult for the nursing dyad, decisions regarding maternal medication use during breast feeding should be based on accurate and up-to-date information. This article reviews available data on the most commonly used antibiotics and analgesics. The use of most antibiotics is considered compatible with breast feeding. Penicillins, aminopenicillins, clavulanic acid, cephalosporins, macrolides and metronidazole at dosages at the low end of the recommended dosage range are considered appropriate for use for lactating women. Fluoroquinolones should not be administered as first-line treatment, but if they are indicated, breast feeding should not be interrupted because the risk of adverse effects is low and the risks are justified. Paracetamol (acetaminophen), low-dose aspirin (acetylsalicylic acid) [up to 100 mg/day] and short-term treatment with NSAIDs, codeine, morphine and propoxyphene are considered compatible with breast feeding. Safer alternatives should be considered instead of dipyrone, aspirin at a dosage >100 mg/day and pethidine (meperidine). In the light of the many safe alternatives for pain control, breast-feeding mothers should not be allowed to experience pain or be made to feel that they must choose between analgesia and breast feeding. 相似文献
39.
N F Hopkins I S Benjamin M H Thompson R C Williamson 《Annals of the Royal College of Surgeons of England》1990,72(4):229-235
Choledochal cyst is a well-recognised entity, presenting primarily in infants and young children. Where symptoms are delayed until adulthood, associated hepatobiliary pathology may complicate the presentation. These problems may be aggravated by previous treatment with bypass surgery rather than resection. We report seven cases from our recent experience presenting with complications in adulthood. These included cholangitis, hepatic abscess, pancreatitis and malignancy within the cyst. Two patients presented during pregnancy. These complications and their implications for management are discussed. 相似文献
40.