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41.
Localizations of J-chain-positive cells (JPC) were examined in chicken lymphatic tissues before and after hatching. The cells containing J chain were first detected in medullary areas of the bursa of FABRICIUS during the embryonic stage. These positive cells were partly detected in the developing small lymphatic follicles: perhaps on newly differentiating precursor B-cells. In addition to these lymphatic follicles, connective tissue of bursal fold were also detected as J-chain positive. Although similar localizations of JPC were again observed in hatched chickens, positive areas of follicular medulla were strongly stained for fluorescence with corresponding antisera than that of embryonic ones. These data may reflect differences in the physiology of lymphocytes in respect to functional development. JPC localizations were next compared between the B-cell subpopulations, mu-(microPC) and alpha-chain-positive cells (alpha PC). The J-chains detectable in the IgM molecules were also found in follicular medulla. However, these follicles were almost found to be negative for J-chains detectable in the alpha PC before hatching. Any strong stainings for J-chain in the alpha PC were, moreover, not be observed in bursa after hatching. The microPC localizations in hatched chickens were roughly equal with the pattern of JPC localization. These analyses revealed the presence of the cells having the chains of both mu and J. The results together with other recent studies further shown that bursal J-chain can be partly detected in newly differentiated lymphatic follicles lacking IgM-producing and suggest the possible presence of B-cell-differentiation sequence of Ig-J+----IgM+J+----IgA+J+. 相似文献
42.
Moriya Hidetaka Maitani Yoshie Shimoda Naoto Takayama Kozo Nagai Tsuneji 《Pharmaceutical research》1997,14(11):1621-1628
Purpose. Recombinant human erythropoietin (Epo) is used frequently through intravenous (i.v.) and subcutaneous (s.c.) administration for the clinical treatment of the last stage of renal anemia. We encapsulated Epo in liposomes to develop an alternative administration route. The purpose of our study was to evaluate the pharmacokinetics and the pharmacological effects of liposomal Epo in comparison with the Epo after i.v. and s.c. administration to rats.
Methods. Epo was encapsulated in liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and soybean-derived sterol mixture (SS) prepared by the reversed-phase evaporation vesicle method. After filtration through a 0.1 m polycarbonate membrane, liposomes were gel filtered (Epo/liposomes).
Results. Epo/liposomes showed higher pharmacological activity than Epo/liposomes before gel filtration after i.v. administration to rats. Non-encapsulated Epo lost its activity, whereas encapsulated Epo in liposomes retained it. The pharmacological effects of Epo/liposomes were greater than those of Epo after i.v. administration. Epo/liposomes afforded 3–9 times higher AUC, lower clearance and lower steady-state volume of distribution than Epo after both i.v. and s.c. administrations. Epo/liposomes had an improved pharmacokinetic profile compared with Epo. S.c. administration of Epo/liposomes at 7 h may penetrate primarily (40% of dose) through the blood as a liposome and partly (7% of dose) in lymph.
Conclusions. Epo/liposomes may reduce the frequency of injections required for a certain reticulocyte effect in comparison to Epo. The lower clearance of Epo/liposomes may increase the plasma concentrations of Epo, which increases the efficacy. 相似文献
43.
Repeat liver resection for recurrent colorectal liver metastases 总被引:11,自引:0,他引:11
Yamamoto J Kosuge T Shimada K Yamasaki S Moriya Y Sugihara K 《American journal of surgery》1999,178(4):275-281
BACKGROUND: This study aimed to delineate the role of surgery for recurrent colorectal cancer in the liver and to identify prognosticators for better patient selection and outcome. METHODS: Data from 90 repeat hepatectomies (second = 75; third = 12; fourth = 3) for recurrent colorectal cancer were collected. RESULTS: After the second hepatectomy, the 3-and 5-year survival rates were 48% and 31%, respectively. Twenty-seven percent (20 of 75) of patients are alive without recurrence after a median follow-up of 27 months, and 9 survived more than 5 years. Four or more tumors, positive regional lymph node metastases, concomitant extrahepatic disease, and residual tumor were independent poor prognostic factors after the second hepatectomy. CONCLUSIONS: Repeat hepatectomy should be applied for recurrent colorectal cancer, when curative removal of the tumor is possible, although the benefit from treatment was limited in a patient with regional lymph node metastases, 4 or more metastases, or extrahepatic disease. 相似文献
44.
Tateishi T Watanabe M Moriya H Yamaguchi S Sato T Kobayashi S 《Biochemical pharmacology》1999,57(8):935-939
Ethnic differences in the pharmacokinetics of nifedipine, a substrate of CYP3A, and in CYP3A7 expression have been reported. The aim of the present study was to measure the protein levels of CYP3A4, CYP3A5, and CYP3A7 and nifedipine oxidation activity in hepatic microsomes from 15 Caucasian and 15 Japanese patients for comparison between the two ethnic groups. Nifedipine oxidation activity and CYP3A4 protein level were well correlated. No significant difference between Caucasian and Japanese microsomal samples was found in nifedipine oxidation activity or in the CYP3A4 protein level. CYP3A5 was detected in 6 of 15 Caucasian samples and in 5 of 15 Japanese samples, but no ethnic difference was found in either the frequency of expression or its protein level. CYP3A7 was found in 10 of 15 Caucasian samples and in 14 of 15 Japanese samples. Although the estimated CYP3A7 protein level was higher in the Japanese than in the Caucasian samples, its protein level was much lower than that of CYP3A4. These results imply that the contribution of CYP3A5 or CYP3A7 to the purported Caucasian-Japanese ethnic difference in the overall CYP3A activity seems to be small. 相似文献
45.
Immunolocalization of basic fibroblast growth factor during wound repair in rat retina after laser photocoagulation 总被引:3,自引:0,他引:3
Chikako Yamamoto Nahoko Ogata Xianjin Yi Kanji Takahashi Miki Miyashiro Haruhiko Yamada Masanobu Uyama Kouichi Matsuzaki 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(11):695-702
Background: Basic fibroblast growth factor (bFGF) stimulates the mitogenesis of various cells and plays a key role in wound repair. We studied the immunohistochemical localization of bFGF during wound repair in the rat retina after laser photocoagulation. Methods: Krypton laser photocoagulation was performed on the eyes of pigmented rats. The eyes were enucleated on days 1, 3, 7, 14 and 28 after the photocoagulation, and the immunohistochemical localization of bFGF was assessed. Two different monoclonal antibodies and one polyclonal antibody against bFGF as first antibodies were used. Results: Marked immunoreactivity for bFGF was found in the ganglion cell layer, and weak immunoreactivity for bFGF was found in the retinal pigment epithelial (RPE) cells of the normal adult rat retina. On day 3 after laser photocoagulation, the nuclei and cytoplasm of proliferating RPE cells at the center of the photocoagulated lesion showed intense bFGF immunoreactivity. The nuclei of RPE cells around the lesion showed intense bFGF immunoreactivity. Macrophages that migrated into the lesion showed positive staining for bFGF. These immunoreactivity decreased with time. Controls (0.05 M Tris-HCl buffer, normal serum, or these same antibodies preabsorbed with bFGF) did not show positive staining. Conclusion: The finding of an elevated expression of bFGF immunoreactivity in the photocoagulated lesion suggests that bFGF may play a role in wound repair in the rat retina after laser photocoagulation. 相似文献
46.
Vertebral decancellation for severe scoliosis 总被引:9,自引:0,他引:9
STUDY DESIGN: The results of staged surgery including vertebral decancellation were reviewed retrospectively for 21 patients with severe scoliosis. OBJECTIVES: To evaluate the benefits and limitations of vertebral decancellation as new anterior surgical procedure. SUMMARY OF BACKGROUND DATA: The curvatures of severe scoliosis are often very rigid, and surgical correction using the anterior or posterior approach may not achieve the desired correction. Some studies reported neurologic complications might appear due to the aggressive approach or excessive correction force. METHODS: Twenty-one patients (average age, 17.0 years) with severe scoliosis, in whom Cobb angle was over 80 degrees (average angle, 107 degrees), underwent staged anterior and posterior spinal reconstruction. Vertebral decancellation was performed as anterior procedure, and until posterior instrumentation, halo traction was carried out. The transition of curvatures in coronal and sagittal planes was assessed in this series. RESULTS: The average correction rate of lateral curvature at the final follow-up was 46%. The average loss of correction was 2.5 degrees. Kyphosis, measured between T5 and T12, changed from 41 degrees to 36 degrees. Lordosis, measured between L1 and S1, changed from 56 degrees to 45 degrees. Transient neurologic deficit was seen in one case after vertebral decancellation. CONCLUSIONS: Staged surgery including vertebral decancellation is an effective surgical method for patients with severe scoliosis, where an inflexible rigid curve or the risk of occurrence of neurologic complications due to temporary correction may exist. 相似文献
47.
Macroscopic features at the deepest site of tumor penetration predicting liver metastases of colorectal cancer 总被引:2,自引:0,他引:2
Inomata M; Ochiai A; Sugihara K; Moriya Y; Yamaguchi N; Adachi Y; Kitano S; Hirohashi S 《Japanese journal of clinical oncology》1998,28(2):123-128
Liver metastasis is the gravest prognostic factor in colorectal cancer. To
identify a reliable indicator for liver metastasis, we evaluated
macroscopic features and seven established histopathological findings at
the cut section containing the deepest penetration using univariate and
multivariate analyses in 417 colorectal cancers. Macroscopic features were
divided into two types, streak type and non-streak type, according to the
presence or absence of white streak(s) at the advancing margin of tumor
invasion. Streak type was observed in 109 patients (26%). The frequency of
liver metastasis in streak type tumors (56%) was significantly higher than
that in non-streak type tumors (13%) (p < 0.001). The white streak
corresponded histologically with cancer cells showing focal
dedifferentiation with marked stromal and perivascular fibrosis extending
towards the serosa or adventitia. In 343 curatively treated patients,
univariate analysis showed that recurrent liver metastasis was
significantly associated with macroscopic features, venous invasion, focal
dedifferentiation and lymph node metastasis. Multivariate analysis
disclosed that macroscopic features and lymph node metastasis were
independent indicators of liver metastasis. These macroscopic features,
corresponding histologically to stromal behavior against invading cancer
cells, are a simple and useful indicator of liver metastasis of colorectal
cancer.
相似文献
48.
49.
Correlation between bone marrow edema and collapse of the femoral head in steroid-induced osteonecrosis 总被引:26,自引:0,他引:26
Iida S Harada Y Shimizu K Sakamoto M Ikenoue S Akita T Kitahara H Moriya H 《AJR. American journal of roentgenology》2000,174(3):735-743
OBJECTIVE: The purpose of this study was to clarify whether bone marrow edema is detectable on initial MR imaging of steroid-induced osteonecrosis of the femoral head. SUBJECTS AND METHODS: Forty-eight hips with osteonecrosis were examined consecutively with MR imaging and radiography. In a previously reported screening program, osteonecrosis was diagnosed on MR imaging when subchondral bands of abnormal signals were present. In the screening program, the MR images of 200 hips of 100 patients receiving high-dose steroid therapy were examined prospectively. Subchondral bands were detected in 48 hips at a mean of 14 weeks after the initiation of steroid therapy. RESULTS: On follow-up MR imaging of 47 hips (one hip excluded) bone marrow edema was initially observed in 13 hips after the onset of hip pain. MR imaging of the remaining 34 hips did not reveal bone marrow edema and the patients were all asymptomatic. MR imaging of 31 of the 34 hips continued to show subchondral bands and MR imaging of the other three hips indicated that the subchondral bands had disappeared. When bone marrow edema was detectable, abnormal findings on radiography were slight but 11 (85%) of the 13 hips progressed to advanced osteonecrosis. Bone marrow edema was highly correlated with the subsequent collapse of the femoral head (p<0.0001). CONCLUSION: Bone marrow edema was not present on initial MR imaging of osteonecrosis. Bone marrow edema should be considered a marker for potential progression to advanced osteonecrosis, and careful examinations for osteonecrosis are necessary when bone marrow edema is seen. 相似文献
50.
A 3‐year‐old Japanese boy presented with a 3‐month history of itchy erythematous papules on his trunk and forearms, the histologic findings of which were characterized by predominantly neutrophilic inflammation within and around the eccrine sweat ducts and obliteration and disruption of the superficial eccrine sweat ducts. Although the skin disorder had some clinical and histopathologic similarity to miliaria and neutrophilic eccrine hidradenitis, it was ultimately conformed to be neither disorder. Based on this and a case report in the Japanese literature of a 1‐year‐old boy with erythematous eruptions whose clinical and histopathologic findings were similar to those in our case, we propose the skin disorder in our case, referred to as “neutrophilic superficial eccrine ductitis,” as a unique entity. 相似文献