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81.
S Fujimoto M Akahane M Hagisawa T Nakajima T Hattori H Sato T Sugawara K Takeda K Ichinoe N Ishiguro 《The Japanese journal of antibiotics》1986,39(10):2632-2638
The transplacental passage of single intravenous doses of aztreonam (AZT), 1 g or 2 g, was examined in 7 sheep and 14 women in late pregnancy, respectively and the obtained data were analyzed by a two-compartment model. The obtained results were summarized as follows. After single 2 g intravenous doses were given to pregnant sheep, the mean peak level of AZT in maternal blood was 83.79 micrograms/ml and the half-life of the beta-phase was 1.525 hours. After single 1 g intravenous doses were administered to pregnant women, the mean peak level of AZT in blood was 102.62 micrograms/ml and the half-life of beta-phase was 2.128 hours. The peak levels in umbilical venous blood and amniotic fluid were 14.43 micrograms/ml and 11.86 micrograms/ml, respectively. 相似文献
82.
Shibahara Hiroaki; Shigeta Minoru; Inoue Miyuki; Hasegawa Akiko; Koyama Koji; Alexander Nancy J.; Isojima Sinzo 《Human reproduction (Oxford, England)》1996,11(12):2595-2599
The blocking effects of complement-dependent sperm immobilizingantibodies in the sera of infertile women and monoclonal antispermantibodies against humans and mice on fertilization were investigated.The hemizona assay (HZA) and sperm penetration assay (SPA) wereused to study the inhibitory effects of sera from 22 infertilepatients positive for sperm immobilizing antibodies. Use ofthese tests allowed us to differentiate whether the antibodyblocked spermzona pellucida tight binding and/or spermpenetration into the ooplasm. The zona pellucida penetrationassay (ZPA) was also used to study the effects of four monoclonalantibodies (mAbs) on human sperm penetration into the zona pellucida.Seven mAbs against murine spermatozoa were tested for theirinhibitory effects on in-vitro fertilization (IVF) and HZA inmice. Of 22 patient sera with sperm immobilizing antibodies,21 (95.5%) inhibited HZA attachment and penetration, whereasthis did not occur in any of 13 patient sera without these antibodies.However, 19 of 22 (86.4%) patient sera with sperm immobilizingantibodies and eight of 13 (61.5%) patient sera without theseantibodies inhibited the SPA. Two (2C6, 1G12) of four mAbs againsthuman spermatozoa showed strong inhibitory effects in all theassays (HZA, ZPA and SPA). One mAb (3B10) did not inhibit HZAbut blocked ZPA and SPA. Another mAb (H6-3C4) seemed to haveno inhibitory effects on fertilization. Two (Vx 5 and Vx 8)of seven mAbs against murine spermatozoa inhibited IVF in micebut did not block mouse HZA. These findings suggest that antispermantibodies block fertilization at specific stages. Some of themmay inhibit sperm capacitation and thus prevent all processesof fertilization that follow. Some other antibodies may notaffect capacitation and sperm binding to zona pellucida butinhibit the acrosome reaction, followed by the blocking of spermpenetration through zona pellucida and ooplasm. 相似文献
83.
Tomoyuki Yamashita M.D. Yoshihide Fujimoto M.D. Takaya Kodama M.D. Akira Hirayama M.D. Takao Obara M.D. Yukio Ito M.D. Motohiko Aiba M.D. Kiyoko Kusakabe M.D. 《World journal of surgery》1988,12(4):559-563
Clinicopathologic studies were performed to establish rational criteria for total thyroidectomy as a treatment of follicular carcinoma. During the 4-year period from 1981 to 1984, total thyroidectomy was carried out on 23 patients in whom unequivocal vascular invasion and/or obvious extracapsular extension were disclosed on pathological study of the primary thyroid lesion. Although occult metastatic lesions were detected postoperatively in 5 patients, no distant metastases have been found in 12. Distant metastasis was clinically manifest on admission in the other 6 patients. The degree of vascular invasion at the primary lesion was not correlated with the occurrence of distant metastasis. However, 10 of the 15 patients with tumors characterized by a thick fibrous capsule had distant metastases, while all but 1 of 8 patients with a thin capsule showed no metastasis. Apparent capsular invasion seemed to increase the relative risk of distant metastasis. On the other hand, solid clusters of tumor cells containing a variable number of small follicles, which characterize Langhans' wuchernde Struma, were found in 6 patients, and 5 of them showed distant metastases. Thus, total thyroidectomy should be considered when (a) distant metastases are clinically apparent, (b) the primary lesion has a thick fibrous capsule with or without obvious capsular invasion, or (c) solid clusters of tumor cells are demonstrated microscopically.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
Resumen Se realizaron estudios clinicopatológicos con el propósito de establecer criterios racionales para la tiroidectomía total en el tratamiento del carcinoma folicular. En el curso de un perfodo de 4 anos entre 1981 y 1984, se realizó tiroidectomía total en 23 pacientes en quienes se halló inequívoca invasión vascular y/o obvia extension extracapsular en el examen histopatológico de la lesión tiroidea primaria. Aunque postoperatoriamente se detectaron lesiones metastáticas ocultas en 5 pacientes, no se encontraron metástasis distantes en 12. Metástasis distantes eran clínicamente manifiestas en el momenta de la admisión en los otros 6 pacientes. El grado de invasión vascular en la lesión primaria no apareció correlacionado con la ocurrencia de metástasis distantes. Sin embargo, 10 de los 15 pacientes con tumores caracterizados por una cápsula gruesa y fibrosa tenían metástasis distantes, mientras solo 1 de 8 pacientes con tumores de cápsula fina mostró metástasis. La invasión capsular aparente parece incrementar el riesgo relativo de metástasis distantes. Por otra parte, agrupaciones sólidas de células tumorales con presencia de números variables de folículos pequeños, que caracterizan al wuchernde Struma de Langhans, fueron encontrados en 6 pacientes, 5 de los cuales mostraron metastasis distantes. Por lo tanto, se debe considerar la tiroidectomía total cuando: (a) haya metástasis distantes clínicamente aparentes, (b) la lesión primaria tenga una gruesa cápsula fibrosa con o sin invasión capsular obvia, y (c) se demuestren microscópicamente agrupaciones sólidas de células tumorales.
Résumé Une étude clinicopathologique a été menée pour déterminer les critères de thyroïdectomie totale comme traitement dans le cancer folliculaire de la thyroïde. Pendant 4 ans, de 1981 à 1984, 23 patients ont subi une thyroïdectomie totale pour envahissement vasculaire non équivoque et/ou extension extracapsulaire évidente découverte sur la pièce d'exérèse initiale. Cinq patients avaient des métastases occultes découvertes dans la période postopératoire, 6 avaient des métastases cliniquement évidentes, alors que 12 ne présentaient aucun signe de métastase à distance. Le degré d'envahissement vasculaire de la lésion primitive n'était pas corrélé avec la survenue de métastases à distance. Cependant, 10 des 15 patients à tumeurs caractérisées par un épaississement de la capsule fibreuse avaient des métastases à distance, alors que 7 des 8 patients avec une capsule mince n'avaient pas de métastases. L'envahissement capsulaire était associé à un plus grand risque de métastases à distance. Des amas solides de cellules tumorales contenant de petits follicules, le wuckernde struma de Langhans, étaient retrouvés dans 6 cas, dont 5 avaient des métastases à distance. Ainsi, la thyroïdectomie totale est préconisée lorsque (a) des métastases à distance sont cliniquement évidentes, (b) la lésion primitive possède une capsule fibreuse épaisse avec ou sans envahissement évident, et (c) on met en évidence des cellules tumorales en amas microscopiquement.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
84.
T Fujimoto 《Gan no rinsho》1988,34(13):1903-1908
The CNS has often been classified as a "drug sanctuary" as most anticancer drugs do not achieve effective penetration of the blood-brain barrier. With more effective systemic chemotherapy program, the incidence of CNS involvement in leukemia has increased. The strategy for treatment of leukemia is that one achieves by destruction of all leukemia cells including CNS. Between 1972 and 1978, 153 children with ALL were treated with multiple methods of CNS-prophylaxis and were analyzed in relation to treatment regimens, age, sex and initial hematologic status. Patients received CNS-prophylaxis; Group I: three doses of intrathecal methotrexate (MTX) and hydrocortisone (HDC), Group II: same as in Group I followed by cyclic MTX and HDC, Group III: same as in Group I plus 2,400 cGy of cranial irradiation. CNS leukemia terminated complete remission in 25 of 153 patients (16.3%). The cumulative incidence of CNS leukemia at 4-year calculated by the Kaplan-Meier Method was 40.5% in Group I, 26.9% in Group II, and 14.5% in Group III. We concluded that the combination of cranial irradiation and intrathecal MTX and HDC was highly efficacious. The efficacy of high-dose MTX with CF rescue therapy for CNS-prophylaxis was evaluated in 62 children with ALL between 1978 and 1980 (protocol 787 study), and was demonstrated to be same as cranial irradiation in standard risk of ALL. In protocol 811 study (1981-1984), the dosage of cranial radiation has been reduced from 2,400 cGy to 1,800 cGy without loss of efficacy for CNS-prophylaxis. Although CNS-leukemia was no longer an unmanageable clinical problem, and the prospects for cure of ALL appeared good, there remained question as to the toxic effects of intensive treatment on the CNS. Successful prevention of these complications will depend in large part on an understanding of their causes. 相似文献
85.
Y Fujimoto Y Hamamura K Inoue K Shirasuna M Urade M Sugiyama M Kogo Y Uchida T Matsuya 《Osaka Daigaku shigaku zasshi》1989,34(2):370-377
The radial forearm flap, or the forearm flap, is called "Chinese flap" for its development of the chinese doctors, and is originally designed for the correction to the post-burn contraction of the face and neck. The radial forearm flap is one of the fasciocutaneous flap, supplied by the radial artery, and transferred as a single-stage reconstruction micro-surgically. In oral and maxillofacial region, the deltopectral flap (D-P flap) and the pectralis major myocutaneous flap (P-M-M-C flap) are mainly used for the reconstruction. These flaps, however, are sometimes too bulky and limited to transfer, and more require two-stage operations. On the other hand, as the forearm flap being thin and pliable, some doctors use this flap micro-surgically at single-stage free flap reconstruction. Before two years, we have begun to transfer the radial forearm flap for the intra-oral reconstruction. The operation method is as follows. Design and Elevation of the Radial Forearm Flap 1. Using the ultrasonic doppler flow meter, the radial artery and the subcutaneous forearm veins are marked on the skin. 2. The flap is designed 20% larger according to the pattern to be reconstructed, with the distal section of the radial artery as an axis on the forearm and the median vein of forearm inclusively. 3. Before the operation, Allen test must be performed in order to determine whether the hand will survive without a radial arterial in-put. 4. The operation is performed with a arm tourniquet. The margin of the flap are incised down to the deep fascia, isolating and preserving the proximal subcutaneous veins as required.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
86.
It has been demonstrated that in vivo T cell priming requires CD154-CD40 interaction, which is suggested to be critical in the induction of co-stimulatory activities on antigen-presenting cells (APC). In the current study, we demonstrate that in vivo administration of a high dose of a superantigen, staphylococcal enterotoxin A (SEA), could up-regulate B7-2 on most splenic APC independently of the CD154-CD40 interaction, followed by efficient expansion of SEA-reactive V(beta)3(+) T cells in CD154- or CD40-deficient mice. However, the CD154-CD40 interaction may be involved in SEA-mediated T cell activation, since a contribution of the CD154-CD40 interaction was observed when a lower dose of SEA was injected. CD154-independent T cell priming by SEA appeared also independent of the TRANCE-RANK pathway, which was shown to be capable of mediating CD154-independent activation of naive T cells during the infection of some viruses. These results indicate that SEA, which provokes rapid and efficient T cell responses without adjuvant, could utilize multiple CD154/TRANCE-independent pathways, to prime T cells. 相似文献
87.
Unrelated patients with achromatopsia, macular degeneration with onset under age 50 years, cone degeneration or dysfunction, cone-rod degeneration, or macular malfunction were screened for mutations in the three genes known to be associated with achromatopsia: the GNAT2 gene encoding the alpha subunit of cone transducin and the CNGA3 and CNGB3 genes encoding the alpha and beta subunits of the cone cGMP-gated cation channel. We found no examples of patients with GNAT2 mutations. Out of 36 achromats, 12 (33%) had mutations in CNGA3 (13 different mutations including five novel mutations) and 12 (33%) had mutations in CNGB3 (six different mutations including four novel mutations). All achromats with CNG mutations had residual, presumably cone function as determined by computer-averaged 30-Hz electroretinograms (ERGs). There was considerable variability in acuity and color vision, with most patients having acuities of 20/200-20/400 and complete absence of color perception, and others having acuities of 20/25-20/40 and some color vision. Two pseudodominant achromatopsia cases were uncovered, both with CNGA3 mutations, including one family in which some compound heterozygotes with achromatopsia mutations were clinically unaffected. We found two novel CNGB3 changes in three patients with juvenile macular degeneration, a phenotype not previously associated with mutations in the cone channel subunits. These patients had subnormal acuity (20/30-20/60), normal to subnormal color vision, and normal to subnormal full-field cone ERG amplitudes. Our results indicate that some patients with channel protein mutations retain residual foveal cone function. Based on our findings, CNGB3 should be considered as a candidate gene to be evaluated in patients with forms of cone dysfunction, including macular degeneration. 相似文献
88.
Histogenesis of the duodenum, especially changes in the epithelium in relation to temporal occlusion and re-canalization of
the lumen, was investigated by light microscopy together with morphometric analysis, as well as by scanning and transmission
electron microscopy of 133 externally normal human embryos ranging from Carnegie stage 12 to 23. A series of morphogenetic
events passed the duodenum in a cranio-caudal (proximo-distal) wave like fashion during the period examined. They included:
(1) a decrease in the caliber and area of the lumen, (2) ’occlusion’ of the lumen, (3) vacuole formation, (4) ’re-canalization’
and villi formation. The only exemption to this rule was that, in the upper part of the duodenum, the lumen was not obliterated
in the embryos examined. Morphometric analyses revealed that both the area of the epithelium and the number of epithelial
cells decreased during the ’occlusion’ phase. This result suggests that, unlike the classical view, epithelial cell proliferation
does not play an important role in occluding the lumen, but the predominant morphogenetic event during this phase is convergence
of the epithelial cells to elongate the duodenum. Apoptosis, contrary to some classical views, decreased during the ’re-canalization’
phase, and it appeared to be involved in the formation of the small lumens in the epithelial ’plug’ and in villi formation,
but not in enlarging the secondary lumens. The secondary small lumens in the occluded lumen were frequently formed near the
border between the central ’plug’ and peripheral basal cells on the basement membrane. This and other findings of concentric
differentiation in both the epithelial and mesenchymal layers suggested a possible control mechanism by the epithelium-mesenchymal
interaction on human duodenal morphogenesis and histogenesis. The present electron microscopic observations also provided
details on the mechanisms involved in the enlargement of the secondary lumen and differentiation of villi. The implications
of these findings to duodenal anomalies are also discussed.
Accepted: 12 November 2001 相似文献
89.
Yamamoto R Isobe T Eguchi T Tang WR Kiyokawa N Amemiya H Fujimoto J Sato E Takagaki Y Yasue H 《Molecular immunology》2005,42(12):1485-1493
Complete porcine CD3ζ-chain cDNA sequence was obtained for the first time, and its genomic nucleotide sequence was investigated from exon 2 down to CD3η-chain exon 8. The sequence of porcine CD3ζ-chain showed homologous amino acid sequence with human and murine counterparts, in contrast to CD3η-chain exon 8 with diversity among animals previously investigated. CD3η-chain peptide is an alternative splice form of CD3ζ-chain exon 7 splicing to CD3η-chain exon 8 instead of CD3ζ-chain exon 8. The genomic sequences revealed that the splice acceptor sequences of CD3η-chain exon 8 of all animals investigated to be completely uniform. Further, CD3η-chain exon 8 amino acid sequences retained the unique characters of having high proline (Pro) and positively charged amino acid content except for rats and mice. Although the biological role of CD3η-chain remains to be enigmatic, these evidences suggests the evolutional pressure to maintain its sequence. 相似文献
90.
Tetsuo Kimoto Fuminori Hyodoh Koji Nishitani Masayoshi Namba Ayako Ueki 《Pathology international》1978,28(1):15-23
Cell-to-cell interaction was investigated in various malignant tumor cells (human ovarial tumor, lung cancer, carcinoma of larynx and hamster melanoma cell) and in human lymphoblastoid cells (T-cell (MOLT-4 cell), thymoma cells and B-cells (Burkitt lymphoma cell)). Live lymphoblastoid cells did not adhere to the cell surfaces of tumor cells nor the lymphoblastoid cells were ingested by tumor cells wihout immunologic and specific treatment. Tumor cells as well as T-cells and B-cells had receptors to concanavalin A on their surfaces, and they showed marked cell binding of tumor cells and lymphoblastoid cells. Moreover, tumor cells that phagocytized lymphoblasts underwent marked cell destruction within 4 hours of cell binding. The cytolytic mechanism of the target tumor cell was probably related to contact with the lymphoblastoid cells and was increased by ingestive activity, and metabolic disturbance by lymphotoxin in tumor cells. 相似文献