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1.
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in...  相似文献   
2.
Photoaging and oxidative stress   总被引:5,自引:0,他引:5  
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3.
Inbred rabbits of B/Jas strain were found to be highly susceptible to herpes simplex virus type 1 encephalitis, following i.v. injection of the virus, while Chbb:HM strain rabbits were not susceptible. The susceptibility trait seemed to be inherited recessively, involving multiple genes, because (B/Jas x Chbb:HM)Fl hybrids were as resistant as Chbb:HM rabbits, and because more than 90% of backcrosses of (B/Jas x Chbb: HM)FI to B/Jas were resistant to viral inoculation. The encephalitis in B/Jas rabbits resembled human herpes simplex encephalitis, in that the temporal lobe as well as the brain stem were affected preferentially, leading to the development of various types of seizures, such as circling, loss of balance leading to a fall, and tonic and clonic convulsions. The disease could be diagnosed by magnetic resonance imaging (MRI) analysis before onset of seizures, and diseased rabbits showed a marked lymphopenia at onset of seizures. © 1995 Wiley-Liss, Inc.  相似文献   
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5.
Tissue distribution of epidermal growth-factor (EGF) in rat was investigated using a human EGF (hEGF) radioimmunoassay system. Antisera generated against hEGF reacted with hEGF and [21Leu] hEGF but not with mouse EGF, fibroblast growth factor (FGF), nerve growth factor (NGF), platelet derived growth factor (PDGF), and endothelial cell growth supplement (ECGS). Similar amounts of EGF immunoreactivity (EGF-IR) were found in the rat submandibular gland (32.8 +/- 4.59 ng/g tissue, n = 5) and duodenum (39.9 +/- 18.7 ng/g tissue, n = 9), whereas little EGF was detected in other tissues. No sex difference was observed in submandibular and duodenal EGF-IR, being different from the case of mouse in which ten times higher concentration of EGF-IR was found in male submandibular gland. Sephadex G-50 gel chromatography of submandibular and duodenal extracts revealed that each consisted of at least three different immunoreactive forms. The predominant EGF-IR was coeluted with 125I-EGF, significant amounts of EGF-IR was observed in the void volume fractions, and only small peaks of EGF-IR were present near Vt. These data clarified the presence of EGF-IR in rat submandibular and duodenal tissues and the molecular heterogeneity of EGF-IR and suggest some important role of EGF in the gastrointestinal function.  相似文献   
6.
Treatment of erectile dysfunction (ED) in hypertensive subjects remains to be formally established. There is currently no standardized treatment for ED in hypertensive subjects. In this study, we tested our hypothesis that hypotensive drugs would improve impaired relaxation in the corpus cavernosum of spontaneously hypertensive rats (SHR). Ten-week-old SHR was treated with amlodipine, imidapril or hydralazine for 4 weeks. Although all three drugs achieved an equivalent decrease in systolic blood pressure (SBP), only amlodipine and imidapril induced an increase in relaxation in response to electrical field stimulation (EFS) of the corpus cavernosum. In the case of amlodipine, this effect was dose- and SBP-dependent. Nitric oxide (NO)-dependent relaxation was increased by amlodipine over a wide range of EFS frequencies, was increased by imidapril at low EFS frequencies, and was decreased by hydralazine. Carbon monoxide (CO)-dependent relaxation was only increased by hydralazine, and this increase occurred over a wide range of frequencies. The NOx and cGMP levels in the EFS-stimulated corpus cavernosum were increased by amlodipine. Amlodipine did not affect the thiobarbituric acid-reacting substance levels in the serum and the corpus cavernosum, but did decrease superoxide dismutase activity in the tissue. Imidapril and hydralazine inhibited the acetylcholine-induced relaxation in the corpus cavernosum. Sodium nitroprusside-induced relaxation in the tissue was increased by amlodipine. All three agents similarly inhibited the phenylephrine-induced contraction. These results suggest that impaired neurogenic relaxation in the corpus cavernosum of SHR is improved by amlodipine and imidapril through an increase in the synthesis and/or release of neuronal NO, but not CO, and presumably the inhibited detumescence of erection, which is induced by norepinephrine being released from sympathetic neuron. These findings indicate that amlodipine and imidapril may ameliorate the decreased relaxation of cavernous smooth muscle in the setting of hypertension.  相似文献   
7.
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
8.
A fully automated chemiluminescence immunoassay was developed for the detection of antibodies to HTLV-I. We used partially purified viral antigens coated on small polystyrene beads together with acridinium ester-labeled anti-human immunoglobulin G mouse immunoglobulin G in this method. A good agreement was observed between our proposed method, the indirect immunofluorescence assay, the particle-agglutination test and the enzyme immunoassay. This new method, which is simple, sensitive, specific and rapid, should be useful for mass screening of anti-HTLV-I antibodies.  相似文献   
9.
The capacity for the generation of oxygen radicals by polymorphonuclear leukocytes (PMNs) was assessed in 29 patients with measles and in control groups. Patients with secondary bacterial infections showed a significantly decreased generation of oxygen radicals; this abnormality did not persist for more than 2 months after disease onset. Normal PMNs incubated with T lymphocytes from these measles patients generated significantly fewer oxygen radicals than those incubated with T cells from either control group. However, normal PMNs incubated with non-T lymphocytes from these measles patients produced normal oxygen radical levels. In addition, irradiation above 1,500 rads of T lymphocytes abrogated the suppressive effect of T cells on PMNs. On the other hand, these abnormal findings were not observed in patients with measles but without secondary bacterial infections. The secondary bacterial infections sometimes seen in measles patients may result from a decrease in oxygen radical generation, presumably induced by the suppressive activity of the T lymphocytes of the patients.  相似文献   
10.
Miyachi S  Hasegawa YT  Gerfen CR 《Neuroscience》2005,134(3):1013-1022
The effect of coincident stimulation of convergent corticostriatal inputs was analyzed by the induction of immediate early genes in striatal neurons. Cortical motor areas were stimulated through implanted electrodes in awake, behaving rats, and the induction of the mRNAs encoding the immediate early genes (IEGs) c-fos and arc was analyzed in the striatum with in situ hybridization histochemistry. In the first experiment, unilateral stimulation of the medial agranular cortex, orofacial region of the lateral agranular cortex or the forelimb region of the lateral agranular cortex resulted in IEG induction in the striatum, which was restricted to the topographically related area receiving input from the stimulated cortical area. In a second experiment, stimulation parameters were altered, including frequency, number of pulses/train, and number of trains/s. These parameters did not have a significant effect on IEG induction. Notably, in some cases, in which there was IEG induction not only in the stimulated cortical region, but also in the homologous area in the contralateral hemisphere, very robust IEG induction was observed in the striatum. In a third experiment, the orofacial regions of the lateral agranular cortex of both hemispheres were stimulated coincidently. All of these animals showed robust striatal IEG induction. This IEG induction was attenuated by pretreatment with an NMDA antagonist MK-801. In a fourth experiment, we tested whether the coincidence of bilateral cortical stimulation contributed to the efficacy of striatal IEG induction. Either alternating stimulation or coincident stimulation of non-homologous cortical regions produced significantly lower striatal IEG induction than obtained with coincident stimulation of homologous cortical areas. Enhanced striatal IEG induction occurred in indirect striatal neurons, labeled with enkephalin, but was also present in a large number of enkephalin-negative neurons, most of which are likely direct pathway neurons. These results suggest that regional and temporal convergence of cortical inputs enhances striatal IEG induction.  相似文献   
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