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排序方式: 共有663条查询结果,搜索用时 15 毫秒
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Marwan H. Saab Douglas C. Smith Paul K. Aka Robert W. Brownlee J. David Killeen 《Cardiovascular and interventional radiology》1992,15(4):211-216
Percutaneous transluminal balloon angioplasty (PTA) was performed in 17 tibial arteries with an average cross-sectional area
stenosis of 92% (range 75–99%) in 13 patients (14 limbs) for limb salvage. In 4 of 14 lower extremities, PTA of femoropopliteal
arteries was also performed. Technical success with 50% or less residual stenosis was achieved in all 17 tibial vessels. At
approximately 2 months after PTA, clinical improvement had occurred in 10 of 14 limbs; no patient was made worse. Most recent
follow-up (mean 19 months, range 8–34 months) revealed continued satisfactory clinical success with no further vascular intervention
in 9 of these 10 limbs (one patient died). Short segmental stenoses, residual stenoses less than 40% following PTA, and absence
of diabetes or gangrene appear to be predictors of favorable clinical outcomes. Our results suggest that PTA of focal tibial
stenosis is an effective and safe treatment modality in properly selected patients and that wider use of PTA may be justified. 相似文献
3.
P M Therizol-Ferly J Tagliante-Saracino M Kone A Konan J Ouhon A Assoumou K Aka G Assale 《Bulletin de la Societe de pathologie exotique (1990)》1989,82(5):690-693
148 adult patients with chronic diarrhoea and suspected to be HIV infected have had stool examinations. 46 are without any enteric parasite. Those detected in the others patients are Sporozoans: I. belli (16.2%) and Cryptosporidium sp. (6.7%) found alone or joint, together or with other parasites. Among those, all Flagellate species are identified, but T. intestinalis (6%) is predominant. Entamoeba coli (8.%) is the most frequent amebic species, however, E. histolytica histolytica have been found twice, once singly, the second associated with I. belli, Schistosoma mansoni and Candida albicans. Necator americanus (14%) and Strongyloides stercoralis (12%) are the predominant worm species. Among the yeasts, C. albicans (35.8%) is the most important species isolated, singly in 13.5% of the patients. In an intertropical and parasitical endemic area where many parasites are not considered uncommon, opportunist agents as I. belli, Cryptosporidium sp. and C. albicans appear in an non-negligible frequency in our study. 相似文献
4.
Russell EJ; Geremia GK; Johnson CE; Huckman MS; Ramsey RG; Washburn-Bleck J; Turner DA; Norusis M 《Radiology》1987,165(3):609-617
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes. 相似文献
5.
Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
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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
10.
Clonal dysregulation of the antibody response to tetanus-toxoid after bone marrow transplantation 总被引:2,自引:0,他引:2
Gerritsen EJ; Van Tol MJ; Van 't Veer MB; Wels JM; Khouw IM; Touw CR; Jol-Van Der Zijde CM; Hermans J; Rumke HC; Radl J 《Blood》1994,84(12):4374-4382
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers. 相似文献