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31.
32.
New thermotropic, liquid-crystalline polyesters ( 5a, b, 6a, b ) with mesogenic bipyridinediyl units were synthesized. They form complexes with Fe(II) and Cu(II) salts. Homopolyesters 5a, b , containing no metal or less than a certain amount of metal, are smectic. A nematic mesophase was observed in the case of copolyester 6a, b . The structural properties of a polyester complex 5a with Cu, as crystal, liquid-crystal and isotropic liquid, were examined by ESR.  相似文献   
33.
At the Hyogo Ion Beam Medical Center (HIBMC) we have developed a new design method for the bar ridge filter used in proton therapy, taking into consideration the scattering and nuclear interaction effects within the filter itself, which are introduced in the design. In our beam delivery system, the bar ridge filter is employed as the range modulator. It is combined with the wobbler system, and produces a three-dimensionally uniform spread-out Bragg peak (SOBP). The design program predicts the three-dimensional dose distribution. Ridge filters of 3-12 cm SOBP in 1 cm increments were designed in the maximum radiation field for 150 MeV and 190 MeV proton beams so that a uniform physical dose area is obtained in the SOBP region three-dimensionally. Measurements were performed with the constructed ridge filters to verify the uniformity and these were compared with the predictions of the design program. The predictions and measurements were found to be in agreement except for the 12 cm SOBP. The uniformities were better than +/- 3.0% for all SOBPs produced. The ridge filters are now clinically in use.  相似文献   
34.
This report describes an anomalous case of the multiple ipsilateral common trunk formation in the parietal arteries encountered during observed in the dissection of a 71 year-old Japanese female cadaver in the anatomical laboratory of Kanazawa Medical University. This subject had thirteen parietal arteries. Among the thirteen parietal arteries two arose from both the subclavian arteries (superior intercostal artery), and eleven arose from the descending aorta (aortic parietal arteries). Five arteries (R-1-R-5) were located on the right side, and eight (L-1-L-8) on the left. Of the eleven aortic parietal arteries, nine formed the ipsilateral common trunk, and the other two were independent branches (left 11th intercostal and 2nd lumbar arteries). The branching states of these parietal arteries were as follows: on the right side, R-1 was the common trunk for the 1st and 2nd intercostal arteries (the right superior intercostal artery), R-2 (was the common trunk) for the 3rd, 4th, 5th, 6th and 7th intercostal arteries, R-3 for the 8th and 9th intercostal arteries, R-4 for the 10th and 11th intercostal arteries and R-5 for the subcostal, 1st, 2nd, 3rd and 4th lumbar arteries. On the left side, L-1 was the common trunk for the 1st and 2nd intercostal arteries (the left superior intercostal artery), L-2 for the 3rd, 4th and 5th intercostal arteries, L-3 for the 6th and 7th intercostal arteries, L-4 for the 8th, 9th and 10th intercostal arteries, L-6 for the subcostal and 1st lumbar arteries, and L-8 for the 3rd and 4th lumbar arteries.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
35.
The mesencephalic trigeminal nucleus (MesV) contains the somata of primary afferent neurons innervating masticatory muscle spindles and the periodontal membrane. MesV afferent somata are unique in receiving synaptic inputs. Intracellular recordings in coronal pontine slices from adult rats were made from MesV neurons identified by having Cs-sensitive inward rectification and pseudounipolar morphology. Stimuli near the MesV evoked either a cluster of action potentials superimposed on a postsynaptic potential (PSP) or an antidromic spike at resting membrane potential (RMP). Membrane hyperpolarization revealed that each cluster of action potentials consisted of an antidromic spike and a subsequent PSP. Evoked PSPs in slices and miniature postsynaptic currents (mPSCs) recorded using whole-cell patch in dissociated MesV neurons were resistant to glutamate antagonists and strychnine but were reversibly abolished by 40 microM bicuculline. Superfusion of 1-10 mM GABA decreased input resistance and depolarized the membrane. Reversal potentials for evoked PSPs and GABA-induced depolarizations were similar and close to that for mPSCs which matched the Cl- equilibrium potential. Thus activation of synapses on MesV somata evokes GABAergic PSPs that generate action potentials at RMP in the adult. These data also indicate that primary afferent MesV neurons can act as interneurons in the central control of mastication.  相似文献   
36.
The susceptibilities of seven T-cell lines to human herpesvirus 6 (HHV-6) infection were examined. MT-4 cells were the most susceptible of these lines to infection with this virus. Therefore, chemically adhered MT-4 cell monolayers were used for infectious HHV-6 assay by indirect immunofluorescent-antibody (IFA) staining. When cell monolayers were fixed 30 to 45 h postinfection, the foci stained with IFA were easy to count and a linear relationship was observed between the number of foci and the virus concentration. MT-4 cell monolayers were also used for a focus reduction neutralizing-antibody test. In this test, sera from patients in the convalescent stage of exanthem subitum all showed significant neutralizing activity (1:80 to 1:320), whereas sera from patients in the acute stage of disease showed no detectable neutralizing activity. The titers of neutralizing antibody correlated well with the levels of anti-HHV-6 antibodies detected by IFA.  相似文献   
37.
Fibroblastic tissue is an important component of malignant tumors, involved in the establishment of metastatic foci from micrometastases, and thought to prevent invasion of metastatic tumor cells into surrounding tissue. However, experimental models of fibrosis during the growth of micrometastasis into established metastases were not previously available. In the present paper, we performed immunohistochemical studies on experimental hepatic metastasis with colon 38 mouse colon carcinoma cells injected into syngeneic C57BL/6 mice. Early and late stages of metastatic nodules were examined for the distribution of endothelial cells, fibroblasts, and macrophages by the use of markers of these cells. One week after intrasplenic injection of colon 38 cells, micrometastases mainly appeared in the region of sinusoids accompanied with invasion of F4/80-positive Kupffer cells. Transitional metastases can be defined based on the histological appearance and intensive infiltration of both macrophages and fibroblasts. These transitional metastases were connected by protrusions of fibroblast-rich tissues co-localized with collagen-rich matrix and CD31-positive cells. This protrusion preceded fibrosis formation characteristics to established metastases associated with angiogenesis and segregation of tumor cells from host cells. Three stages can thus be classified during the development of hepatic metastasis in this syngeneic experimental system: micrometastasis, transitional metastasis, and established metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
38.
BACKGROUND: FK506 ointment (tacrolimus ointment, protopic) is a new drug therapeutically effective for patients with atopic dermatitis (AD). However, the mechanism of action of FK506 ointment on AD is not fully understood. METHODS: We examined the effect of FK506 ointment on mite antigen-induced dermatitis in NC/Nga mice. Clinical symptoms and ear thickness were recorded, and histopathological studies and in vitro analyses were performed. RESULTS: Topical application of FK506 ointment (0.03-0.3%) suppressed the development of dermatitis. In the lesional skin, both interleukin (IL)-4 and interferon (IFN)-gamma were detected, even though the IL-4+/IFN-gamma- T helper 2 (Th2) population was predominant in the regional lymph nodes (LNs). Topical application of FK506 treatment reduced the elevated level of both IL-4 and IFN-gamma in the skin, but did not decrease the expansion of the Th2 population in the LNs. CONCLUSIONS: Topical application of FK506 ointment suppresses dermatitis by inhibiting the activation of inflammatory cells locally, without systemic immune suppression, in this AD model.  相似文献   
39.
40.
A new method for evaluating histamine release from purified basophils was developed. Basophil-containing leukocytes were directly purified from a small amount of peripheral blood using monoclonal antibody BA312-coated magnetic beads. The purified basophils still rosetted to magnetic beads maintained a normal response to anti-IgE and to dust mite allergen in comparison with the conventional method using washed leukocytes. This methodology facilitates the purification of basophils, anti-IgE- and allergen-induced histamine release, and subsequent histamine determination within only 3 h. The released histamine was analyzed by an enzyme-linked immunosorbent assay (ELISA) with a characteristic detection profile. Since all steps were performed in 96-well microplates, many clinical samples could be analyzed at the same time, permitting easy applications in routine laboratories.  相似文献   
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