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21.
Infusion of muscimol (5×10−5 M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos-like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system.  相似文献   
22.
Type A aortic dissection: evaluation with ultrafast CT   总被引:3,自引:0,他引:3  
  相似文献   
23.
Antinociceptive effects of sodium hyaluronate (Na-HA) were studied on the basis of improvement in the graded abnormal gait elicited by arthritis induced by intra-articular administration of monosodium urate crystal (MSU) to rats. One hour before MSU injection, intra-articular administration of a 1.0% solution of Na-HA with different molecular weights, ranging from 4.70 x 10(5) to 2.02 x 10(6) (HA-200), improved the score of abnormal gait in a molecular weight-dependent manner in the experimental arthritis model. Similarly, administrations of HA-200 at concentrations ranging from 0.1 to 1.0% prior to MSU treatment resulted in improvement of the score in abnormal gait in a dose-dependent manner. To elucidate the antinociceptive mechanisms of Na-HA, effects of pretreatment with Na-HA (1.0%) of different molecular weights on prostaglandin E2 (PGE2) and bradykinin (BK) releases in synovial fluid 3 hr after MSU injection were studied. Increases in PGE2 and BK concentration in the synovial fluid were depressed in a molecular weight-dependent manner by Na-HA (1.0%) pretreatment. These results indicate that Na-HA attenuates the nociceptive responses inflicted by the MSU-induced arthritis. Such an antinociceptive effect may be due to the inhibition of PGE2 and BK synthesis in the synovial joint of rats.  相似文献   
24.
Adult T-cell leukemia/lymphoma (ATLL) is recognized as a disease etiologically associated with human T lymphotropic virus type-1 (HTLV-1) infection, but, neither viral replication nor specific virus antigen expression have been detected on ATLL cells distributed in organs, including skin. To examine the latent expression of HTLV-1 in the cutaneous lesions of ATLL patients, we cultured the lesional skin tissues in vitro and applied immunofluorescence staining with mouse monoclonal antibodies Lt-4, GIN-14, and F10, which react with p40tax, p19 and gp21, respectively. We recognized HTLV-1 specific antigens on clustered ATLL cells only in the deeper dermis of the skin after 24 hrs cultivation of the lesional skin tissue from an ATLL patient in RPMI-1640 medium supplemented with 20% fetal calf serum. In the electron microscope, we observed HTLV-1 like particles, 80-140 nm in diameter with envelope and core structures, in the same tissue specimen. These findings suggest that HTLV-1 gene products may be expressed in the skin lesions of ATLL patients and involved in the pathogenesis of skin eruptions in cutaneous type ATLLs. To our knowledge, this is the first report that envisages the potency of intracutaneous HTLV-1 expression in vivo.  相似文献   
25.
A 54 year-old female who had a history of hemoptysis was admitted to our hospital because of dyspnea on effort. Pulmonary arterial pressure was elevated and pulmonary arteriography showed multiple pulmonary arterial aneurysms and occlusion of the left upper lobe pulmonary artery. Systolic pulmonary arterial pressure was 110 mmHg when measured by continuous wave Doppler echocardiography. From the clinical and angiographical findings, we diagnosed this patient as having Hughes-Stovin's syndrome (forme fruste). 30 mg of diltiazem per day was initially used, and 80 mg was used thereafter. After 2 months follow up of the medication with diltiazem, systolic pulmonary arterial pressure decreased from 110 mmHg to 61 mmHg and clinical symptoms improved dramatically.  相似文献   
26.
Between 1950 and 1986, 14 cases of primary carcinoma of the fallopian tube were treated and diagnosed at the Cancer Institute Hospital. These cases constituted 0.13% of the total number of gynecologic malignancies at the hospital during the period. The clinical/pathological findings and prognoses were described. Of the 14 cases, the average age was 56.0 years. The most frequent symptom was atypical genital bleeding, seen in 11 cases (79%). Massive watery discharge was seen in four cases (29%). In preoperative cytologic examination of vaginal smears, six cases (43%) were positive for cancer. All cases underwent operation as therapy. Postoperative irradiation, adjuvant chemotherapy, and/or second-or third- look operation was also used. Histopathologically, all materials were found to be adenocarcinoma. Four cases were well differentiated, seven were moderately differentiated, and three were poorly differentiated. Two patients with stage III and IV cancers died of the disease. Nine patients were still alive at the end of this study. The five-year survival rate was 57% (4/7). In stage I cancers, the five-year survival rate was 80% (4/5). The prognosis of stage I cancer patients was estimated as rather good.  相似文献   
27.
Neuropathological studies were carried out on 180 human immunodeficiency virus-seronegative intravenous drug addicts. The findings in victims of acute heroin intoxication (n = 116) were congestion (99.1%), capillary engorgement (68.1%), and/or perivascular bleeding (68.1%) – hemodynamic processes attributable to toxic primary respiratory failure. In a high percentage of these cases (88%), cerebral edema was also present. In 18 cases of acute heroin intoxication who survived for periods of hours or days, the sole postmortem finding was ischemic nerve cell damage, resembling that typically seen in systemic hypoxia. Semiquantitative analysis revealed nerve cell loss in the hippocampal formation and/ or Purkinje cell layer in 26% of the 162 chronic drug abusers. By contrast, in nearly 80% of these cases, the hippocampus showed enhanced expression of glial fibrillary acid protein by astrocytes and/or a proliferation of microglia, demonstrated by CD68 expression. Since such reactive processes are produced by primary neuronal damage, it can be assumed that chronic intravenous drug abuse results in obviously ischemic nerve cell loss. This could be demonstrated in the hippocampus, but it must also occur throughout the whole brain. The demonstration of ischemic nerve cell damage and neuronal loss or secondary reactive alterations has not been described previously. Received: 31 March 1995 / Revised, accepted: 27 November 1995  相似文献   
28.
29.
S Hamada  R Itoh  S Fujita 《Cancer》1988,61(8):1555-1562
The DNA distribution pattern was determined by cytofluorometry in 25 cases of colorectal small carcinoma and the so-called severe dysplasia. The colorectal carcinoma and "severe dysplasia" consisted of four principal stemlines as to DNA ploidy: diploidy, aneuploidy, and their respective polyploidies. These patterns appeared in various combinations in individual neoplasms. DNA distribution of the severe dysplasia was diploid-predominant (11 cases) or aneuploid-predominant (three cases), usually showing mosaicism in various degrees with respective first order polyploidy. Similar DNA distribution patterns also were found in submucosally invasive small carcinomas. The neoplastic cell populations of a higher polyploidy (second or third order), however, occurred only in the submucosally invasive carcinomas (three cases) regardless of their basic ploidy. The mitotic index tended to be higher in the aneuploid-predominant tumors than in the diploid-predominant tumors. In the current observation, there was no significant correlation between the DNA distribution pattern and histologic type of the "dysplasia" or carcinoma. We found that most of the so-called severe dysplasias of the colon and rectum already gained definitive characteristic of carcinoma in the DNA pattern, i.e., ploidy heterogeneity. Therefore, they can be identified as intramucosal carcinomas, distinct from the normal epithelia and adenomas of the colon and rectum.  相似文献   
30.
Sensitivities and abilities of quantitative detection for Candida albicans of five simplified diagnostic aids for candidosis or denture stomatitis--Microstix-Candida, Stomastat medium, Mizuno- Takada medium, CA-TG medium, and "milk test"--were examined in vitro, and the characteristics or the indications for clinical use of these summarized.  相似文献   
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