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381.
This paper aimed to study Lower Miocene (Burdigalian) mixed carbonate–siliciclastic deposits within an Upper Cenozoic synorogenic conglomerate–dominated succession in north of Shalamzar in the Zagros foreland basin, Iran. The deposits are composed of nine facies: foraminiferal mudstone, silty mudstone, sandy mudstone, fossiliferous sandy mudstone, fossiliferous argillaceous mudstone, fossiliferous calclithite, coral limestone, calcareous claystone and hybrid sandstone. The facies represent a mixed carbonate– siliciclastic shelf–type fan–delta. The subenvironments of the fan–delta include muddy pro–delta, sandy delta– front, clastic proximal mouth bar and a subordinate delta plain. Siliciclastic input and sedimentation rate controlled the paleoecological distribution of different benthic carbonate–producing fauna in the fan–delta during its progradation into a shelf marine environment. Input of siliciclastic deposits and sedimentation rate limited the diversity and development of corals and controlled their colonization and growth morphologies in the sandy delta–front. Siliciclastic input (including plant materials and coal debris) and sedimentation rate controlled the trophic habitats of many gastropods and their abundance and distribution in the sandy delta– front and clastic proximal mouth bar. Also, increased siliciclastic input favored abundance of larger benthic foraminifera in most parts of the fan–delta with the exception of the muddy pro–delta.  相似文献   
382.
The fine needle aspiration (FNA) biopsy findings were compared with the results of fine needle cutting (FNC) biopsy in 40 patients. The lesions (38 pulmonary nodules, 1 mediastinal mass and one lytic rib lesion) were biopsied with 22-gauge Greene and 21-gauge E-Z-EM needles through a 19-gauge needle guide. The FNA biopsy findings were based on smears and cell blocks of material obtained with the Greene needles while the FNC biopsy findings were based on tissue cores obtained by the E-Z-EM needles. In 83% of the cases, both techniques yielded specimens with similar cellularity; in seven cases, the FNA samples were more cellular. Malignancy was diagnosed in 80% of the patients: by both techniques in 26 patients, by FNA biopsy only in 5 patients and by FNC biopsy only in 1 patient. The sensitivity of FNA biopsy was higher than that of FNC biopsy (96.8% vs. 84.3%). The specificity and predictive value of positive results were 100% for both techniques. The predictive value of negative results was higher for FNA biopsy (88.8% vs. 54.5%). The majority of FNC biopsy tissue cores consisted mostly of clotted blood, lung tissue and/or fibrous tissue and did not facilitate or improve the diagnosis. Those data suggest that the contribution of FNC biopsy to the diagnosis of thoracic neoplasms is very limited and that the performance of FNC biopsy with an E-Z-EM needle in addition to or instead of FNA biopsy is not justified.  相似文献   
383.
Inflammatory bowel disease (IBD) is a chronic inflammatory condition with an unknown etiology. Nicorandil, a potassium channel opener, has been used for many years for the treatment of angina. Recently, it has been shown that nicorandil possesses some novel traits such as anti-apoptotic, gastroprotective, free radical scavenging, and anti-inflammatory properties. Therefore, we set out to examine the possible beneficial effect of nicorandil in a rat model of IBD. Colitis was induced by rectal administration of 2,4,6-trintrobenzene sulphonic acid (TNBS) into rats. Groups of animals used in this study were sham, control, and exposure to dexamethasone, nicorandil, glibenclamid (a pure adenosine triphosphate sensitive potassium channel (KATP) blocker), or nicorandil plus glibenclamid. Drugs were administered by gavage and animals were sacrificed after 7 days. Biochemical markers, including TNF-α and IL-1β, ferric reducing/antioxidant power (FRAP), myeloperoxidase (MPO) activity and thiobarbitoric acid-reactive substance (TBARS), were measured in the homogenate of colonic tissue. Results indicate that nicorandil significantly reduces macroscopic and histological damage induced by TNBS. Nicorandil diminishes MPO activity and levels of TBARS, TNF-∢, and IL-1β in damaged colonic tissue with a concomitant increase in FRAP value (P<0.01). These effects were not reversed by coadministration of glibenclamide. In conclusion, nicorandil is able to ameliorate experimental IBD with a dose in which it does not show any anti-hypertensive effect, and the mechanism of which is partially or totally independent from KATP channels. It is hypothesized that nitric oxide donation and free-radical scavenging properties of nicorandil upregulate endothelial nitric oxide synthase may be responsible for this phenomenon. These findings suggest that nicorandil can be useful in treatment of IBD, although further investigations are needed to elucidate the mechanisms involved.  相似文献   
384.
The cytopathologic, immunohistochemical and ultrastructural features of a case of Ki-1-positive lymphoma are presented and discussed. On fine needle aspiration (FNA) biopsy smears, the Ki-1-positive lymphoma was characterized by large isolated cells with abundant dense/vacuolated cytoplasm and large nuclei with irregular profiles. Although most cells contained one nucleus, binucleated and multilobed/multinucleated cells were also seen. The cohesion of the malignant cells in histologic sections of a biopsied lymph node suggested an anaplastic carcinoma. The discrepancy was resolved by ultrastructural and immunologic analyses. The main differential diagnoses on FNA material include Hodgkin's disease, malignant melanoma and undifferentiated carcinoma; the cytologic suspicion should be confirmed by immunocytochemical studies.  相似文献   
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