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31.
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent.  相似文献   
32.
Safe use of cricoid pressure   总被引:1,自引:0,他引:1  
  相似文献   
33.
Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma.  相似文献   
34.
Four new antibiotics, TMC-171A (2), B (3), C (4) and TMC-154 (5) have been isolated from the fermentation of fungal strains Gliocladium sp. TC 1304 and TC 1282, respectively. Spectroscopic and degradation studies have shown that TMC-171s and TMC-154 were new members of the TMC-151 class of antibiotics, unique polyketides modified with a D-mannose and a D-mannitol or a D-arabitol. These compounds showed moderate cytotoxicity to various tumor cell lines.  相似文献   
35.
E5531 is a synthetic disaccharide analogue of lipid A which has a low toxicity but retains the ability to reduce production of tumour necrosis factor. This analogue has potential for use in the treatment of septic shock. An injectable formulation of E5531 would be useful, but dispersion in aqueous solution is a problem. In the present study the dispersing process for E5531 was evaluated using the pH-jump method (pH 11.0-->7.3). The size of the aggregates was decreased (reaching 20 nm) with increasing dispersing time in 0.003 M NaOH (pH 11.0). The membrane fluidity of the aggregates increased with increasing dispersing time. When prepared by the normal dilution method (pH 7.3-->7.3), the size of the aggregates remained constant at 140 nm and the membrane fluidity was smaller than that of samples prepared by the pH-jump method. This indicates that during dispersing at basic pH, the hydration proceeded in a normal manner, but then stopped, just after adjustment of the pH to 7.3. This suggests that the degree of hydration of the membrane is dependent on the dispersing time at pH 11.0. Using samples with different degrees of hydration and different membrane fluidity prepared by the pH-jump method, the pharmacokinetics and stability of the aggregates were evaluated after intravenous injection into rats. The data thus obtained confirmed that the membrane fluidity was correlated with the pharmacokinetics and stability in rat plasma. It was concluded that the pharmacokinetics of E5531 in rats can be controlled by changing the degree of hydration and membrane fluidity by means of using different dispersing times in alkaline solution (pH 11.0).  相似文献   
36.
Stable aqueous dispersions of sesame oil (SO) were obtained by co-sonication with soybean phosphatidylcholine (PC) in the SO mole fraction range of 0.1-0.8. In order to clarify the dispersal mechanism, the dispersed particles were characterized and the interaction of SO with PC was investigated using several physicochemical techniques. Dynamic light scattering measurements showed that the diameter of the dispersed particles was 40-60 nm. The trapped aqueous volume inside the particles was determined fluorometrically using the aqueous space marker, calcein. The trapped volume in the SO/PC particles decreased remarkably with the addition of SO into small unilamellar vesicles of PC. The decline in fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the PC membrane by the addition of the quencher CuSO4. These results indicate that the excess SO separated from the PC bilayers is stabilized as emulsion particles by the PC surface monolayer. Monolayer-bilayer equilibrium of SO/PC mixtures was estimated by measurements of spreading and collapse pressures. The results showed that the coexistence of emulsion particles (surface monolayer of PC + core of SO) with vesicular particles (bilayer) was critically important for the formation of stably dispersed particles of the lipid mixture.  相似文献   
37.
A 3 y.o. boy suffered cardiac arrest after submersion in a winter pond for more than fifteen minutes. He was transferred to our hospital and was successfully resuscitated. Although his neurological condition was severely damaged at the beginning, he started searching objects with his eyes on the 18th hospital day, speaking on the 65th hospital day and walking by himself on the 76th hospital day. His consciousness fully recovered eventually. The treatments consisted of "HYPER" as suggested by Conn AW, et al. and active anti-hypertensive therapy. These treatments and the cold temperature of winter time might have contributed to the good neurological recovery of the patient.  相似文献   
38.
We investigated the biological effect of combining carbon-beam and X-ray in vitro. The results showed that when we employed Gray equivalent as the indication of therapeutic dose, the effects could be explained with simple additive way in the treatment plan. This fact provides important information about the combined therapy of carbon-beam and X-ray.  相似文献   
39.
Gastric emptying in the fundus, body, and antrum of the stomach was evaluated by ultrasonography (US) in 41 control children aged 2 to 18 years and 30 patients aged 1 to 19 years who had undergone pyloromyotomy because of hypertrophic pyloric stenosis. The gastric emptying curve decreased in an exponential manner for both control children and patients, while there was no significant difference in gastric emptying time (GET) between control children and patients within any of the age groups. However, GET was faster for younger children in both groups. An X-ray contrast study of the stomach performed in 2 patients who showed markedly delayed GET showed delayed gastric emptying but no significant deformities of the prepylorus. Our results suggest that US is a reliable method of measuring GET in children.  相似文献   
40.
Serum interleukin-18 levels are elevated in schizophrenia   总被引:6,自引:0,他引:6  
Interleukin-18 (IL-18) is a recently discovered proinflammatory cytokine which plays a pivotal role in T helper 1 (Th1) responses. IL-18 is produced by macrophage-like cells, and inappropriate IL-18 production has been known to be involved in immunological disturbances. Schizophrenia is a common disease whose pathogenesis is still unclear; however, an activation of the inflammatory response system, including the Th1 cytokine response, may be related to the pathophysiology of schizophrenia. We measured the serum IL-18 levels of 66 schizophrenics and age- and sex-matched control subjects by using an ELISA assay. We found significantly increased serum IL-18 levels in the schizophrenic patients (P=0.0002). This finding supports the hypothesis that immune activation is involved in the pathophysiology of schizophrenia.  相似文献   
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