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131.
Nakajima K Kinuya K Mizutani Y Hwang EH Michigishi T Tonami N Kobayashi K 《Annals of nuclear medicine》1999,13(1):5-11
Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function. 相似文献
132.
133.
The purpose of this study was to examine the anti-inflammatory effect of the calcium channel blocker nicardipine. Intraocular inflammation was induced by argon laser photocoagulation of the iris of pigmented rabbits and was assessed by measuring aqueous flare and intraocular pressure. This resulted in a marked increase in the aqueous flare that peaked at approximately one hour following coagulation and returning to the original values after six hours. Intraocular pressure increased within 15 minutes following laser treatment and returned to baseline levels at 60 minutes. Pre-treatment of the rabbits with an intravenous injection of 2 mg/kg of nicardipine completely abolished both the increase in aqueous flare and intraocular pressure induced by laser photocoagulation as compared to the control experiment. Earlier work from the author's group has shown that nicardipine can also block aqueous flare and intraocular pressure increases induced by topical administration of prostaglandin E2. From these combined experiments they would like to draw the conclusion that the inflammatory reaction induced by photocoagulation of the iris is partly mediated by prostaglandins and that blockade of calcium channels by nicardipine can inhibit the effects induced by prostaglandin E2. 相似文献
134.
Masahiko Fujita Eigo Takabatake Keiko Tsuchiya 《Archives of environmental contamination and toxicology》1982,11(5):645-649
Experiments were made to observe the effects of the maternal administration of cadmium and zinc and their influence on the metal-binding capacity of metallothionein in the rat fetus. Metallothionein was detected in the fetal liver as early as day 16 of gestation and may have appeared earlier. The zinc concentration in the metallothionein fraction was low on day 16 but increased as gestation progressed. The metal-binding capacity was fairly high on day 16 but increased at a slower rate than the zinc concentration. Following the intraperitoneal administration of zinc (100 moles Zn/kg) or cadmium (5 moles Cd/kg) once a day on days 14, 15 and 16 of gestation to the dam, the concentration of zinc in the metallothionein fraction of the maternal liver was far greater than that in the fetal liver. In contrast, cadmium was found only in the metallothionein fraction of the maternal liver; it was not found in the fetal liver, which suggests an effective placental barrier to cadmium. The metalbinding capacity in the fetal liver was induced by the maternal administration of zinc, but not cadmium. 相似文献
135.
I Miyoshi S Hiraki I Kubonishi Y Matsuda H Kishimoto T Nakayama T Tanaka H Masuji I Kimura 《Cancer》1977,40(6):2999-3003
An Epstein-Barr virus (EBV)-negative lymphoma line (JBL) was established in vitro from pleural effusion of an EBV-seropositive 29-year-old Japanese female with Burkitt's lymphoma. JBL cells as well as her original lymphoma cells bore monoclonal surface IgM with lambda light chains. The JBL line grew in single cell suspension with a doubling time of 30 hours. Attempts were made to serially transplant JBL cells in antilymphocyte serum-treated newborn hamsters; intraperitoneal implantation of 1-3 X 10(7) cells gave rise to invasive tumors in all recipients with death after 10 to 14 days. The hamster-passage line, now in the 9th passage, has been converted to an ascitic form with progression to leukemia in some animals. A "starry sky" pattern closely resembling the human tumor material was preserved in every tumor through serial animal passage. 相似文献
136.
Kaoru Inouye Tomohiro Ito Hidekazu Fujimaki Yoshimasa Takahashi Toshitada Takemori Xiaoqing Pan Chiharu Tohyama Keiko Nohara 《Toxicological sciences》2003,74(2):315-324
In the humoral immune response to an invasion of foreign antigens, B cells differentiate into low-affinity antibody-forming cells (AFCs) that mainly secrete IgM or, through germinal center (GC) formation, into high-affinity AFCs that secrete IgG-class antibodies with a higher affinity for the antigen. Previous studies have established the suppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on low-affinity antibody responses to antigens. However, whether and how TCDD affects the high-affinity antibody response to antigens has not yet been clarified. In this paper we investigate the effects of TCDD on GC formation, high-affinity AFC generation, and high-affinity antibody production in the primary humoral immune response. C57BL/6 mice were orally administered 0 or 20 microg/kg of TCDD and subsequently immunized with alum-precipitated ovalbumin (OVA) on day 0. Then the GC formation in the spleen and OVA-specific antibodies in the plasma, was evaluated until day 14 postimmunization. TCDD exposure reduced the production of OVA-specific IgG1 on days 10 and 14. GC formation in the spleen was also suppressed by TCDD exposure, and the suppression persisted from day 7 until day 14. In TCDD-administered mice, on day 7, cellular proliferation in the GCs was significantly suppressed, although apoptosis was not markedly affected. In order to measure high-affinity antibody and high-affinity AFCs, the mice were administered TCDD followed by immunization with alum-precipitated (4-hydroxy-3-nitrophenyl) acetyl linked to chicken gamma-globulin (NP-CG). The frequency of high-affinity NP-specific AFCs that bind to low-haptenated antigen was clearly shown to be reduced in the spleen on days 10 and 14. Furthermore, the high-affinity anti-NP IgG1 levels on days 10 and 14 postimmunization were significantly reduced by TCDD exposure. Taken together, the results of this paper demonstrate that TCDD exposure inhibits the generation of high-affinity AFCs and high-affinity antibody production during the primary humoral immune response and suggest that these alterations were caused by the suppression of antigen-responding B-cell proliferation induced by TCDD during GC formation. 相似文献
137.
Amir Onn Takeshi Isobe Wenjuan Wu Satoshi Itasaka Tomoaki Shintani Keiko Shibuya Yokoi Kenji Michael S O'reilly Isaiah J Fidler Roy S Herbst 《Clinical cancer research》2004,10(24):8613-8619
PURPOSE: The purpose is to evaluate whether inhibition of epidermal growth factor receptor (EGFR) activation by PKI166, an EGFR-tyrosine kinase inhibitor, affects growth of human lung cancer implanted orthotopically into the lungs of nude mice. EXPERIMENTAL DESIGN: Lungs of mice were injected with NCI-H358 human bronchioloalveolar cancer cells. In three experiments, groups of mice (n = 10 per group) were randomized 7 days after tumor implantation to receive one of the following treatments: i.p. paclitaxel 100 or 200 microg (4 or 8 mg/kg) once per week, oral PKI166 100 or 200 mg/kg three times per week, paclitaxel plus PKI166, or i.p. saline and oral PKI166-vehicle (control) for 5 weeks. Mice were killed 6.5 to 8 weeks after tumor implantation. The experiments were repeated with PC14PE6 human lung adenocarcinoma cells to assess effect on survival. RESULTS: Immunohistochemical analyses revealed the expression and phosphorylation of EGFR in the growing tumors. Treatment with PKI166 alone or in combination with paclitaxel diminished activation of EGFR on tumor cells, yet maximal therapeutic effect was observed in mice treated with paclitaxel alone. Activated mitogen-activated protein kinase and basic fibroblast growth factor expression were similar in all treatment groups. Survival in mice treated with the combination of paclitaxel and PKI166 was shorter than in those treated with paclitaxel alone. CONCLUSIONS: Our results suggest that concurrent administration of EGFR-tyrosine kinase inhibitor and chemotherapy is equivalent and may indeed be inferior to chemotherapy alone, even if EGFR is functional and its phosphorylation effectively inhibited. Our data show that the interaction of EGFR-TKIs and chemotherapy is complex and suggest that other growth factors may activate the downstream signaling events. 相似文献
138.
Toshio Yoshihara Keiko Nagai 《International journal of pediatric otorhinolaryngology》1997,40(2-3):181-187
A rare case of a 5-year-old female with schwannoma of the maxillary sinus is presented. She had complained of painless swelling of the left cheek and hard palate for a duration of one year. Preoperatively, a CT scan strongly suggested it to be a maxillary cyst with an erupted tooth rather than neoplasm. The tumour was completely removed after embolization of the left internal maxillary artery. The tumour was composed of spindle cells in a palisading pattern and intercellular collagenous fibres. Mitotic figures and atypical nuclei were not observed. Immunohistochemically, the majority of the cells were positive for NSE and S-100 protein, whereas GFA and PCNA showed little immunoreaction. The pathological diagnosis was Antony type A of schwannoma arising in the maxillary sinus. 相似文献
139.
Keiko Yamanaka Nikolaos V. Sofikitis Ikuo Miyagawa Yasuhisa Yamamoto Toshiko Toda Spyros Antypas Dimitrios Dimitriadis Manami Takenaka Koji Taniguchi Katsuhiko Takahashi Sanae Tsukamoto Hiroshi Kawamura Martin Neil 《Journal of assisted reproduction and genetics》1997,14(1):55-62
Purpose: Our objective was to apply ooplasmic round spermatid nuclear injections for the treatment of nonobstructive azoospermia.
Materials: Participants were nine azoospermic men who had previously undergone diagnostic testicular biopsy. Spermatogenetic arrest
was diagnosed at the round spermatid stage (n=6) or primary spermatocyte stage (n=3). A second (therapeutic) testicular biopsy
was performed and round spermatid nuclei were recovered from all the participants.
Results: Forty-nine mature oocytes were successfully injected with nuclei and then cultured for 72 hr. Twenty-four embryos were transferred
to nine women. No pregnancy was achieved.
Conclusions: Round spermatids can be recovered from therapeutic testicular biopsy material of men negative for round spermatids in previous
routine diagnostic testicular biopsy specimens. Round spermatid nuclear injections may play a role in the treatment of nonobstructive
azoospermia. 相似文献
140.