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1.
2.
The identification of atypical testicular germ cells is often difficult by by routine histologic examination. By immunohistochemical detection of placental alkaline phosphatase (PLAP) and by periodic acid Schiff staining of glycogen, atypical germ cells were easily identified in testicular samples. Forty-one fetal and adult testes were used for a preliminary study, and 121 testes from infants and adults with either cryptorchidism or germ cell tumors were studied for the presence of atypical germ cells. Two types of clear germ cells were differentiated histochemically, and one with PLAP-positive cell surfaces and glycogen-rich cytoplasm was considered to be atypical. The alkaline phosphatase of atypical germ cells appeared to be similar to that found in a few germ cells of early fetal testes. The atypical germ cells seemed to be multi-potential malignant cells capable of developing not only into seminoma but also into other germ cell tumors. Only in yolk sac tumor of infants were the atypical germ cells absent from tumor-adjacent seminiferous tubules. 相似文献
3.
Masafumi Kataoka Kaori Shigemitsu Shunsuke Tanabe Toshinori Ohara Takaomi Takahata Soichiro Nose 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(7):365-368
A 67-year-old man was admitted to our hospital due to esophageal cancer. Cancer existed at the lower esophagus and subtotal esophagectomy and lymphadenectomy was performed. The postoperative course was uneventful. Pathological findings revealed moderately differentiated squamous cell carcinoma that metastasized to the abdominal lymph nodes which include the paraaortic lymph nodes. He complained of anorexia three months after the operation and was found to have multiple liver and mediastinal lymph node metastases. He was admitted for chemotherapy. Before starting chemotherapy, he suddenly died without any sign of hemorrhage or respiratory disorder. Autopsy showed metastatic lesions to the heart and mediastinal lymph nodes, liver, thoracic vertebrae, kidney, adrenal gland and heart. Metastatic nodules in the heart were on the ventricular septum where the conducting system exists. No direct invasion from the pericardium was observed. Blockade of the conducting system of the heart was considered to have caused the severe arrhythmia and sudden cardiac arrest. 相似文献
4.
Naoharu Iwai Tadashi Inagami Masahiko Kinoshita 《Clinical and experimental pharmacology & physiology》1994,21(11):913-914
1. We have recently identified a candidate gene for rat genetic hypertension, termed Sa, by identifying an mRN A species that shows markedly higher expression in the kidneys of spontaneously hypertensive rats (SHR) than in those of Wistar-Kyoto rats (WKY). 2. Subsequent genetic co-segregation analyses by ourselves and others indicated that the Sa gene locus did indeed influence blood pressure. Moreover, in a preliminary association study, we found an association of a polymorphism of the human Sa gene with essential hypertension. 3. Further studies to identify functions of the Sa gene products are required before reaching a definite conclusion. 相似文献
5.
N Iwai H Nakamura M Miyazu M Katayama K Kasai 《The Japanese journal of antibiotics》1990,43(9):1629-1648
Pharmacokinetic , bacteriological and clinical studies on norfloxacin (NFLX), a quinolone-carboxylic acid antibacterial agent, were conducted in the pediatric field. 1. Serum concentrations and urinary excretion of NFLX after single dose of 2.2 approximately 5.6 mg/kg (mean 4.4 +/- 1.2 mg/kg) were determined in 13 children with ages between 6 and 11 years. The mean peak serum concentration of the drug was 0.37 +/- 0.20 micrograms/ml at 2 hours after administration. The mean half-life of the drug in serum was 2.8 +/- 0.4 hours and the serum concentration at 8 hours was 0.11 +/- 0.06 micrograms/ml. The mean urinary concentration reached a maximum of 125.2 +2- 166.2 micrograms/ml in pooled urine from 0 to 2 hours and the mean urinary recovery rate in the first 8 hours after administration was 22.1 +/- 6.0%. A dose-response relationship was observed between doses/body weight and peak serum concentrations. 2. The clinical efficacy, bacteriological efficacy and the safety of NFLX were evaluated in 65 pediatric patients with ages between 2 years 10 months and 15 years 7 months with infections. In 62 assessable cases (acute purulent tonsillitis 9 cases, acute pneumonia 3 cases, chronic rhinitis 1 case, urinary tract infections 15 cases, and acute colitis 34 cases), clinical efficacies were excellent in 48 cases, good in 13 cases, and fair in 1 case with an overall efficacy rate of 98.4%. Staphylococcus aureus 1 strain, Staphylococcus epidermidis 1 strain, Escherichia coli 10 strains, Salmonella sp. 5 strains, Morganella morganii 1 strain, Pseudomonas aeruginosa 3 strains, Haemophilus parainfluenzae 1 strain and Campylobacter jejuni 12 strains were isolated from the patients as pathogens. Bacteriologically, all of these strains were eradicated except that 3 strains of C. jejuni only decreased. With regard to side effects, dizziness and nausea were observed in 1 case each but they were slight and the continuation of the treatment was possible. No abnormal laboratory test data were observed. From the above results, NFLX was considered to be a useful drug for the treatment of pediatric infections. 相似文献
6.
Satomi-Kobayashi Seimi Kawashima Seinosuke Sakoda Tsuyoshi Ueyama Tomomi Hirase Tetsuaki Kawai Miki Toh Ryuji Iwai Kenji Yokoyama Mitsuhiro 《Circulation journal》2004,68(3):247-253
BACKGROUND: Glycogen synthase kinase-3 beta (GSK-3beta) is involved in many cellular processes, such as metabolism, apoptosis, differentiation and proliferation. Insulin-like growth factor-1 (IGF-1), which is well known to have a hypertrophic effect on cardiomyocytes, inactivates (phosphorylates) GSK-3beta in some cell types. The role of GSK-3beta in cardiomyocytes as a negative regulator of cardiac hypertrophy has been recently reported and the present study investigated the role of GSK-3beta in the cardiac hypertrophy of cultivated neonatal rat cardiomyocytes induced by IGF-1. METHODS AND RESULTS: First, the IGF-1 induced signal transduction leading to GSK-3beta in neonatal rat cardiomyocytes was examined. The phosphatidylinositol (PI) 3-kinase/Akt/GSK-3 beta signaling induced by IGF-1 was investigated using inhibitors of PI 3-kinase and Ad AktAA, a dominant negative form of Akt. Furthermore, using Ad MEK DN, a dominant negative form of MEK, it was found that MEK negatively regulates Akt phosphorylation upon IGF-1 stimulation. Next, it was examined whether GSK-3beta acts as a negative regulator in the cardiac hypertrophy induced by IGF-1. Sustained stimulation by IGF-1 caused cardiac hypertrophy in protein synthesis and cellular morphology, and overexpression of unphosphorylatable GSK-3beta (Ad GSK-3beta S9A) repressed these hypertrophic effects of IGF-1. CONCLUSIONS: GSK-3beta may play an important role as a negative regulator of cardiac hypertrophy induced by IGF-1. 相似文献
7.
M Kanai M Egashira T Murata Y Iwai M Seki 《No shinkei geka. Neurological surgery》1989,17(11):1073-1076
Appropriate diagnostic procedure for spinal epidural hematomas has not been established yet. The authors reported a case of spontaneous epidural hematomas at the thoracic level, in which correct diagnosis was made with MRI and good results were obtained by surgery. A 63-year-old female experienced a severe back pain which appeared suddenly during a walk and was followed by motor weakness in both legs deteriorating quickly to paraplegia. The patient had no history of hypertension, trauma or bleeding tendency. The laboratory data were normal. On admission, neurological examination revealed flaccid paraplegia, total sensory loss below the level of Th 6 and urinary and fecal incontinence. Myelograms showed incomplete block at the Th 6 level and postmyelographic CT scan showed an isodense mass, which was suspected to be an epidural tumor located behind the spinal cord. Emergent MRI confirmed an epidural hematoma as a high intensity area extending from Th 3 through Th 11. Sixty-five hours after onset, laminectomy of Th 4 through Th 11 and the evacuation of epidural hematoma were performed without identification of the origin of the bleeding. Neither vascular malformation nor tumor was recognized during operation. Neither was it noticed on histological examination. The patient made favorable progress after the surgery. During the first two weeks in the postoperative period, she regained muscle strength enough to do standing exercise, and satisfactory improvement was made in sensory function including urination and defecation. We emphasize that MRI is indispensable to make a differential diagnosis of thoracic lesions. In the reported case, a correct diagnosis was made with MRI, and an extremely good result was obtained by an emergency operation. 相似文献
8.
K Sasai H Iwai T Yoshizawa S Nishimoto Y Shibamoto Y Kitakabu N Oya M Takahashi M Abe 《International journal of radiation biology》1992,62(2):221-227
We have previously reported that KU-2285, a 2-nitroimidazole with a fluorinated N1-substituent (-CH2-CF2CONH(CH2)nOH, n = 2), was a promising hypoxic cell radiosensitizer. In this study the pharmacokinetics of KU-2285 and its related compounds (n = 3 and n = 4) were compared with those of etanidazole (a 2-nitroimidazole with an N1-substituent of -CH2CONH(CH2)nOH, n = 2) and its related compounds (n = 3 and n = 4) to assess the effects of incorporation of a CF2 group. The lipophilicity of the fluorinated compounds was higher than that of etanidazole, as measured by the octanol/water partition coefficient. As the number of CH2 groups increased, the lipophilicity of the compounds in both the KU-2285 and etanidazole series increased. The brain tissue levels of the fluorinated compounds were as low as those of the etanidazole derivatives, while the biological half-lives of the fluorinated compounds in peripheral nervous tissues were shorter than those of related non-fluorinated compounds. 相似文献
9.
OBJECTIVE: We have recently isolated a gene, designated as the SA gene, which is more than 10 times more abundantly expressed in the kidneys of spontaneously hypertensive rats (SHR) than in those of Wistar-Kyoto (WKY) rats. To address the issue whether the SA gene is one of the genes responsible for the hypertension of SHR, a genetic cosegregation analysis of the blood pressure values with the genotypes in an F2 rat population was undertaken in this study. METHODS AND DESIGN: Male F2 rats were bred from SHR and WKY rats. The genotypes of the SA gene of the F2 rats were determined by utilizing the StuI restriction fragment length polymorphism of the SA gene between SHR and WKY rats. The blood pressure values were determined by the tail-cuff method. The effect of the genotype of the SA gene on the blood pressure of the F2 rats was analysed by one-way analysis of variance. RESULTS AND CONCLUSION: The blood pressure of the F2 rats inheriting two SHR alleles of the SA gene was significantly higher than that of the F2 rats inheriting two WKY alleles. This indicates that the SA gene, or a gene closely linked to it, has a capacity to influence the blood pressure values of the F2 rat population. Further studies to identify functions of the SA gene products will be necessary. 相似文献
10.
Yoshitaka Ohnishi Takeshi Yoshitomi Toshinori Murata Taiji Sakamoto Tatsuro Ishibashi 《Medical Electron Microscopy》2002,35(1):46-52
The purpose of this histological study was to determine the effects of photodynamic treatment, using a hematoporphyrin derivative and argon laser, on normal retinas of monkeys. Ten cynomolgus monkeys were treated with a hematoporphyrin derivative, given intravenously at a dose of 2.5 mg/kg. Forty minutes or 1 or 3 days after the injection, argon laser photoradiation was given over a 2.0-mm-diameter with a 10-min exposure and at an intensity of 40, 100, or 200 mW. The eyes were enucleated 1, 3, 4, 15, 18, 21, 35, or 38 days after the photoradiation and tissue samples were observed under a transmission electron microscope. The most fragile regions in the retina were the retinal nerve fibers, the outer segments of the visual cells, and the retinal pigment epithelium. Vascular endothelial cells were also fragile. The retinal capillary was easily obstructed, and the choriocapillaris was also occluded in an animal with severe retinal damage. The Mueller cells had the highest tolerance to the photodynamic treatment. Thus, exposing the normal part of the retina to light during photodynamic therapy should be avoided. 相似文献