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排序方式: 共有434条查询结果,搜索用时 15 毫秒
1.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
2.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
3.
Roger E. Kelley MD Alireza Minagar MD Bradford J. Kelley Regina Brunson RVT 《Journal of neuroimaging》2003,13(1):85-87
Meningovascular syphilis is now quite uncommon, but there have been increasing reports in patients immunocompromised with human immunodeficiency virus. The response of syphilis affecting the central nervous system to antibiotic therapy remains a challenge. This is an even greater challenge in patients who have underlying compromise of the immune system. The authors present a 46-year-old male with recurrent stroke who was found to have cerebrospinal fluid compatible with syphilitic involvement of the central nervous system and a cerebral arteriogram, which revealed focal narrowing of the right middle cerebral artery. The baseline transcranial Doppler study demonstrated increased mean and peak flow velocity within the right middle cerebral artery. Despite a 10-day course of intravenous penicillin, with substantial improvement in the cerebrospinal fluid results, this flow velocity elevation persisted, in a remarkably consistent pattern, over a 4-month follow-up period. Thus, the involved vessel remained patent following treatment, but no clear resolution of the stenotic lesion was observed. 相似文献
4.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
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7.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
8.
Variable infection risk following allogeneic blood transfusions 总被引:1,自引:0,他引:1
M E Brunson R Ing J I Tchervenkov J W Alexander 《The Journal of surgical research》1990,48(4):308-312
These studies address infection risk of allogeneic transfusion in an untraumatized, nonseptic rodent model. A' Segaloff Cancer Institute rats served as blood donors and Lewis rats as recipients. Lewis rats' delayed-type hypersensitivity (DTH) response and their ability to clear subdermal Staphylococcus aureus abscesses and Candida albicans pyelonephritis were measured as tests of the effect of transfusions. The effect of pharmacological immunosuppression with either cortisone acetate or cyclosporine provided a "yardstick" to measure the magnitude of transfusion effects. Repeated transfusions at 1-week intervals diminished DTH response to recall antigens (keyhole limpet hemocyanin), but otherwise they showed no evidence of immunosuppression in these experiments. In contrast, we found that transfusions by themselves produced mild immunostimulation. Subcutaneous Staphylococcus abscesses were smaller in animals receiving transfusions. The magnitude of immunostimulation from one transfusion was sufficient to reverse the immunosuppressive effect of cyclosporine by about 50% in a Candida pyelonephritis infection. These studies suggest that blood transfusions have complex interactions with different components of the immune response. T-cell function is impaired by repeated transfusions (diminished DTH response), but other inflammatory responses are accentuated. This suggests that blood transfusions may harm immune response in traumatized animals by causing excessive complement activation or cytokine release. 相似文献
9.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
10.
Allen Snider Kacey Hight Allison Brunson Nalin Payakachat Amy M. Franks 《American journal of pharmaceutical education》2021,85(3)
Objective. To describe criteria for evaluating faculty scholarship within the promotion and tenure guidance documents of US schools and colleges of pharmacy.Methods. Promotion and tenure documents were obtained from the websites of US pharmacy schools or requested via electronic mail, and institutional characteristics were collected from publicly available online data. A qualitative content analysis was conducted to systematically catalogue document characteristics and criteria for promotion and tenure.Results. Promotion and tenure guidance documents from 121 (85%) of 142 pharmacy schools were analyzed. Institutions were 55% public and equally distributed across Carnegie institutional classifications as well as geographic and extramural funding stratifications. Publications (94%) and grants and contracts (87%) were the most frequently included criteria for faculty advancement. More than 50% of schools recognized the criteria within promotion and tenure guidance documents but did not explicitly require faculty to achieve them before receiving promotion and/or tenure. For institutions that required publications for advancement, the most frequently required criterion was publication in peer-reviewed journals (47%). Few schools (22%) documented a specific number of required publications.Conclusion. This analysis provides a comprehensive review of scholarship criteria in academic pharmacy promotion and tenure guidance documents. There was wide variability among scholarship criteria, and documents often lacked specific language defining scholarship requirements. As a result, faculty may find the documents less helpful for self-assessment and preparation toward promotion and/or tenure. These benchmark data can assist pharmacy faculty and administrators in developing and revising promotion and tenure guidance documents to include clear criteria and better align with peer institutions. 相似文献