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1.
Release of cholecystokinin from rat cerebral cortex in vivo: role of GABA and glutamate receptor systems 总被引:1,自引:0,他引:1
Using cortical cups in chloralose-urethanized rats, the in vivo release of cholecystokinin-like immunoreactivity (CCK-LI) from cerebral cortex was examined. Resting levels of cholecystokinin-like immunoreactivity ranged from 20 to 30 pg/20 min sample. The addition of potassium (40 mM) in excess, resulted in a highly significant elevation in the levels of CCK-LI in the cortical superfusate. Deletion of calcium and the substitution of cobalt (10 mM), resulted in a significant reduction in both resting release and the release otherwise evoked by the addition of potassium. Focal electrical stimulation of the cortex (20 Hz), resulted in a significant (1.9 +/- 0.2-fold, n = 8) increase in the levels of CCK-LI. The addition of glutamate (10(-6)-10(-4) M) of kainic acid (10(-8)-10(-6) M), also resulted in significant elevations in the levels of CCK-LI. The co-administration of a putative glutamate receptor antagonist, kynurenic acid (10(-4) M) resulted in a significant reduction in the levels of release otherwise evoked by the addition of glutamate, but not by electrical stimulation. The addition of GABA (10(-5)-10(-3) M) resulted in a dose-dependent decrease in the resting release of CCK-LI, and the release evoked by glutamate. Picrotoxin (10(-6)-10(-4) M), resulted in a highly significant increase in the levels of CCK-LI in the cortical effluent. These results are consistent with a tonic GABAergic inhibition of CCK-releasing neurons. The treatment of the animal with diazepam (30 mg/kg, i.p.) also resulted in a significant reduction in resting release and the release otherwise evoked by focal cortical stimulation. 相似文献
2.
3.
Shoko Nakajima Hiroaki Umebayashi Rumiko Kurosawa Tomoyuki Imagawa Shigeki Katakura Masaaki Mori Yuko Aihara Shumpei Yokota Tuyoshi Sogo Ayano Inui Tomoo Fujisawa Norio Hanzawa 《Nihon Rinshō Men'eki Gakkai kaishi》2005,28(3):154-158
A 10-year-old girl with autoimmune hepatitis (AIH) was reported. She was admitted to our hospital because of cholestasis and elevation of liver enzymes for 2 months. Laboratory examination revealed that EBV-DNA copy number in the PBMNC (peripheral mononuclear cells) was 1.2 x 10(3) copies/microg of DNA, hypergammaglobulinemia, and positive antinuclear antibody, positive anti-smooth muscle antibody. The histology of her liver biopsy specimen revealed interface hepatitis, dense mononuclear cell infiltrates, mild fibrosis, and negative for EBV in situ hybridization assay indicating AIH and not EBV-associated hepatitis. She was treated firstly with methylprednisolone pulses, then will prednisolone p.o.+azathioprine p.o.. Intravenous cyclophosphamide pulse therapy was introduced because of her abnormal immune pathology. All abnormal laboratory parameters improved to normal levels within 2 months, and EBV-DNA copy number in the PBMNC became negative after 4 months. The histology of liver biopsy specimen was useful for the diagnosis of AIH in such a difficult case needed to be differentiated from EBV hepatitis. 相似文献
4.
Hitoya Ohta Tomoo Komibuchi Hideki Nishiyama Kohzo Shizuki Yasuo Miyaki 《Annals of nuclear medicine》1992,6(3):191-193
Tumor scintigraphy with 67Ga-citrate, 99mTc(V)-DMSA and 99mTc-MDP were performed on a patient with rare primary pulmonary leiomyosarcoma. While 67Ga-citrate accumulation to the tumor was not recognized, 99mTc(V)-DMSA and 99mTc-MDP scintigraphy showed relatively intense localization of the tracers in the lesion, and were very useful in suggesting the characteristics of the tumor. 相似文献
5.
Esophageal perforations are extremely difficult to diagnose and treat. We report herein our results of a review of 26 patients
with esophageal perforation which were spontaneous in 11, iatrogenic in 11, and caused by a foreign body in 4. Surgical treatment
was performed in 7 of the patients with spontaneous rupture, but the remaining 19 patients were treated conservatively. The
abnormality was found by plain radiography (X-ray) in 22 (85%) of the 26 patients, and by computed tomography (CT) in all
13 patients who underwent this procedure. The detection rates by esophagography and esophagoscopy were 100%, or all of 25
patients examined, and 60%, or 9 of 15 patients examined, respectively. Of 12 patients with underlying diseases, 4 (33%) died
after the perforation, whereas only 1 (7%) of 14 patients without any underlying disease died. Postoperative empyema developed
in all of 3 patients treated by intraoperative unfixed intrathoracic drainage (UID), but in none of the 4 treated by fixed
intrathoracic drainage (FID). Conservative treatment achieved satisfactory results for spontaneous esophageal ruptures confined
to the mediastinum, and for iatrogenic perforations and esophageal perforations caused by foreign bodies, provided there was
no serious underlying disease such as advanced cirrhosis. Moreover, intraoperative FID proved useful in helping to prevent
postoperative empyema. 相似文献
6.
Immunohistochemical detection of hepatocellular carcinoma in the setting of ongoing necrosis after radiofrequency ablation. 总被引:3,自引:0,他引:3
Tomoo Itoh Yasuko Orba Hidehiro Takei Yusuke Ishida Makoto Saitoh Hideaki Nakamura Takashi Meguro Shoichi Horita Miri Fujita Kazuo Nagashima 《Modern pathology》2002,15(2):110-115
After radiofrequency ablation (RFA), hepatocellular carcinoma undergoes complete necrosis and an ongoing necrosis that is irreversible and characterized histologically by disrupted cell outlines, homogenous cytoplasmic eosinophilia, and preserved nuclear staining, with the cells appearing quite distinct from viable cancer cells. Antibody to detect single-stranded DNA (ssDNA) specifically labeled nuclei in the setting of ongoing necrosis, but not viable tumor cells, whereas human mitochondrial antibody labeled the cytoplasm of viable cells but not cells of ongoing necrosis. The results demonstrate that RFA causes denaturation of both DNA and proteins and that the immunohistochemistry of ssDNA and mitochondrial protein is useful in detection of ongoing necrosis after RFA and provides pathological information on the validity of this procedure. 相似文献
7.
During the immune response to T cell-dependent antigen, somatic hypermutation (SHM) is introduced into immunoglobulin (Ig) genes. The variable region is the target for SHM and it is here that DNA lesions are introduced and mutations are generated. It has been suggested that error-prone DNA polymerase(s) may play an important role in this mutagenesis phase. Recently, DNA polymerase kappa (Polkappa), which belongs to the Y-family of DNA polymerases, was identified. Since a hot spot of SHMs (RGYW motif) is also a hot spot of mutations by human Polkappa, this enzyme was suggested to be an SHM instigator. In order to address the question whether Polkappa is involved in SHM, we immunized Polkappa-deficient mice and analyzed the SHM of the Ig heavy chain gene. We found that the SHM frequency and spectrum were indistinguishable between the Polkappa knockout mice and control mice. These results suggested that Polkappa is not essential for this process. 相似文献
8.
Yasuyuki Tezuka Hiroshi Imai Tomoo Shiomi 《Macromolecular chemistry and physics.》1997,198(2):627-641
A series of mono- and bifunctional polystyrenes ( 1 c and 1 ′ c ) having 1-methylpyrrolidinium salt end groups were prepared through sequential derivatization, i.e., tosylation and quaternization reactions, of prepolymers having 3-hydroxypropyl groups ( 1 a and 1 ′ a ) produced by end-capping reactions of the relevant living polymers. The 1-methylpyrrolidinium salt end group was found to undergo a selective ring-opening reaction at 100°C by nucleophilic attack of a benzoate counter anion introduced by ion-exchange reaction. The ion-coupling reaction of 1 c and 1 ′ c with poly(styrene-co-acrylate salt) was found to take place upon coprecipitation of an equimolar mixture into methanol to afford ionically linked pseudo-graft and network products, respectively. The subsequent heat treatment, converting the ionic bond into a covalent one, results in branched and crosslinked polystyrene with predetermined structural parameters. 相似文献
9.
R. Inagi H. Kosuge S. Nishimoto K. Yoshikawa K. Yamanishi 《Archives of virology》1996,141(11):2217-2223
Summary The novel herpesvirus-like DNA sequences, which were identified in AIDS-related Kaposi's sarcoma (KS) and designated KS associated herpesvirus (KSHV) or human herpesvirus 8 (HHV-8), have been reported to be associated with various forms of KS. Here, we searched for the presence of KSHV sequences in various other skin lesions including premalignant or malignant skin tumors of a total of 69 clinical cases without immunodeficiency due to AIDS or following organ transplantation. Strikingly high rates of detection were obtained for premalignant Bowen's disease and malignant squamous cell carcinoma, accounting for 71.4% and 50%, respectively. A less frequent but as yet high incidence (33.3%) was scored for actinic keratosis, a premalignant epidermal disorder. In contrast, the frequency remained low (16.7%) for another type of proliferative skin lesions of extramammary Paget's disease and non-proliferative skin lesions (dermatitis, morphea, epidermal cyst and scar). These results suggest a close association of KSHV with at least some non-KS malignant and premalignant skin lesions in non-immunocompromised patients. 相似文献
10.
Kyogi Ogoshi Tomoo Tajima Toshio Mitomi Kimiyoshi Tsuji 《Clinical & experimental metastasis》1996,14(3):277-281
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer. 相似文献