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21.
The value of diagnostic aids in detecting pancreas cancer 总被引:2,自引:0,他引:2
P J Fitzgerald J G Fortner R C Watson M K Schwartz P Sherlock R S Benua A L Cubilla D Schottenfeld D Miller S J Winawer C J Lightdale S D Leidner J S Nisselbaum C J Menendez-Botet M H Poleski 《Cancer》1978,41(3):868-879
By contract with the National Cancer Institute, the accuracy of diagnostic techniques was assessed in 184 patients suspected of having pancreas cancer. Of 138 patients who were operated upon, 89 were found to have pancreas duct cancer, 30 had cancer of a different site of origin in the head of the pancreas region and in 19 there was no evidence of cancer at operation. All of the 46 patients who were not operated upon, 13 proven to have cancer and 33 patients discharged as free of cancer, were followed in our clinic. The majority of our patients presented with signs and symptoms of biliary obstruction. Computerized transaxial tomography (CTT) gave a "correct" diagnosis in 31 of 33 patients (94%) with proven cancer, there were 2 patients with a false negative report and a false positive diagnosis occurred in 8 of 20 patients (40%) without cancer. Celiac angiography (CA) gave a correct diagnosis in 78 of 94 patients (83%) with cancer, a false negative in 17%, and a false positive in 32%. 76Selenomethionine pancreas scan correctly diagnosed 27 of 36 patients (75%) with cancer, gave a false negative in 25% and a false positive in 31%. Ultrasonography gave a correct diagnosis in 18 of 27 patients with cancer (67%), a false negative in 33% and a false positive in 28%. Endoscopic retrograde cholangiopancreatography diagnosed correctly 8 of 11 cases (73%) of cancer, there were false negative diagnoses in 3 cases (27%) and false positives in 3 of 14 patients (21%). Duodenal aspiration techniques gave a very low percentage of correct diagnoses. Chronic pancreatitis most commonly gave rise to a false positive diagnosis. Serum alkaline phosphatase was elevated in 82% of patients, gave 18% false negatives and 33% false positives. Carcinoembryonic antigen (CEA) was elevated (greater than 2.5 ng/ml) in most of the pancreas cancer patients but also in patients with other cancers and with non-cancerous diseases. In our hands, CTT, CA, alkaline phosphatase, 75Se-methionine and ultrasonography, in descending order, have given the highest percentage of correct diagnoses but false positive and false negative diagnoses prevented any single test from being conclusive. 相似文献
22.
23.
Oberyszyn TM; Conti CJ; Ross MS; Oberyszyn AS; Tober KL; Rackoff AI; Robertson FM 《Carcinogenesis》1998,19(3):445-455
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate
adherence of leukocytes to vascular endothelium and the associated ligand,
intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2
integrin proteins to allow transendothelial migration of leukocytes into
sites of inflammation. The present study examines the function of these
proteins in a murine model of acute cutaneous inflammation induced
following topical application of 12-O- tetradecanoylphorbol-13-acetate
(TPA) to the dorsal epidermis of SENCAR mice and in a model of skin
multistage carcinogenesis. At 24 h following topical application of TPA to
the dorsal epidermis of mice, dermal leukocytes expressed higher levels of
beta2 integrin protein compared with the lower levels of beta2 integrin
protein expression by peripheral blood leukocytes. ICAM-1 protein was
localized to epidermal keratinocytes and vascular endothelium in
TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.)
injection of either 50 microg anti-beta2 integrin antibody alone or in
combination with anti-ICAM-1 antibody significantly inhibited both
TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and
myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P
< 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but
had no effect on TPA-induced epidermal hyperplasia. In addition, injection
of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in
combination with anti-beta2 integrin antibody (P < 0.001) significantly
inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8-
OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2
integrin/ICAM-1 adhesion molecules work in concert to regulate migration,
retention and functional activation of leukocytes within the dermis during
TPA-induced skin inflammation and within stromal tissue of papillomas that
form during multi-stage carcinogenesis. Agents that inhibit these
receptor/ligand interactions may be useful in defining the roles of
specific cell populations in cutaneous inflammation and multistage
carcinogenesis and may also have potential as anti-promoting and
anti-progression agents.
相似文献
24.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
25.
CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献
26.
27.
28.
Background
Although bacterial cholangitis is frequently mentioned as a cause of secondary sclerosing cholangitis, it appears to be extremely rare, with only one documented case ever reported. 相似文献29.
Human interleukin-5 (IL-5) regulates the production of eosinophils in human bone marrow cultures: comparison and interaction with IL-1, IL-3, IL-6, and GMCSF 总被引:33,自引:1,他引:33
Recombinant human interleukin-5 (rhIL-5), in either liquid or semi- solid cultures, selectively induced eosinophil production from normal human bone marrow, with no activity on other cell lineages. The time course of eosinophil production induced by murine IL-5, rhIL-3, and rh granulocyte-macrophage colony stimulating factor (GMCSF) was similar to rhIL-5. The rate of eosinophil maturation in vitro was independent of the stimulating cytokine, mature eosinophils being produced after 4 to 5 weeks in liquid culture with each of these cytokines. The eosinophils produced in response to each cytokine were morphologically indistinguishable, and had the ultrastructural features of maturity except that the electron-dense material in the granules had not formed into crystalline cores. Neither rhIL-1 nor rhIL-6 alone, or in combination with rhIL-5 or rhIL-3, induced eosinophil differentiation or proliferation under the conditions used. rhIL-3 and rhGMCSF induced more eosinophil colonies than rhIL-5, rhIL-5 had an additive, not synergistic, effect on eosinophil colony production when combined with either rhIL-3 or rhGMCSF, suggesting that rhIL-5 stimulates a smaller and possibly different population of eosinophil progenitors. However, rhIL-5 induced the greatest eosinophil production in liquid cultures, suggesting that although it may act on a smaller population of precursors, it is able to stimulate more proliferative steps than either rhIL-3 or rhGMCSF. 相似文献
30.
Zielinsky A; Hirsh J; Straumanis G; Carter CJ; Gent M; Sackett DL; Hull R; Kelton JG; Powers P; Turpie AG 《Blood》1982,59(2):346-350
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice. 相似文献