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81.
Summary Morphological changes in nasal blood vessels induced by - and -adrenergic and cholinergic agonists were studied under a scanning electron microscope after removal of extracellular connective tissue and the basal lamina. Arterioles were constricted and dilatated following topical application of -adrenergic and cholinergic agonists. Distinctive morphological changes were observed on their smooth muscle cells. Smooth muscle cells of constricted arterioles had a rugged surface with numerous fine invaginations. However, in dilatated arterioles the cells had a smooth surface and intercellular spaces were clearly revealed. No remarkable changes were produced in smooth muscle cells by the -adrenergic agonist. It is concluded that nasal arterioles are sensitive to -adrenergic and cholinergic stimulation but not to -adrenergic stimulation.  相似文献   
82.
From October 2000 to September 2001, we collected the specimen from 410 patients with lower respiratory tract infections in 16 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various anti-bacterial agents and antibiotics and patients' characteristics. Of 499 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 493 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 73, Haemophilus infiuenzae 99, Pseudomonas aeruginosa (non-mucoid) 64, P. aeruginosa (mucoid) 14, Klebsiella pneumoniae 25, Moraxella subgenus Branhamella catarrhalis 21, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 53.8%. Vancomycin and arbekacin had the most potent activities against MRSA as observed in 1999. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) was 38.4% being consistent with that in 1999 (34.7%). PRSP accounted for 11.0% of the total, being more than that in 1999 (3.0%). Carbapenems had strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 73 strains at 0.125 microgram/ml. Generally, all drugs had strong activities against H. influenzae with MIC80s of 8 micrograms/ml or less. The drug that had the strongest activity against H. infiuenzae was levofloxacin, which inhibited the growth of 94 of the 99 strains at 0.063 microgram/ml. Tobramycin had a strong activity against P. aeruginosa (both mucoid and non-mucoid) with MIC80 of 1 microgram/ml. The mucoid strain was little isolated (14 strains) but the susceptibilities to all drugs were better than the non-mucoid strain. K. pneumoniae showed good susceptibilities to all drugs except ampicillin and the MIC80S were 2 micrograms/ml or less. Particularly, cefpirome, cefozopran, and levofloxacin had strong bactericidal activities against K. pneumoniae with MIC80s of 0.125 microgram/ml, and cefotiam, second-generation cephems, also had a favorable activity being MIC80 of 0.25 microgram/ml. Also, all drugs generally had strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or less. The drug having the strongest activity was imipenem and levofloxacin inhibiting all 21 strains at 0.063 microgram/ml. Most of the patients with respiratory infection were aged 70 years or older, accounting for approximately a half of the total (44.4%). As for the incidence by the diseases, bacterial pneumonia and chronic bronchitis were the highest, being noted in 38.0% and 31.7% of all the patients, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (18.3%) and S. pneumoniae (16.1%). In contrast, H. infiuenzae (20.4%) and P. aeruginosa (both mucoid and non-mucoid: 16.7%) were frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from all the patients were S. pneumoniae (24.3%) and H. infiuenzae (26.7%). The frequency of isolated S. pneumoniae tended to decrease with the increase in the number of administration days while that of isolated H. infiuenzae did not. The frequency of isolated P. aeruginosa tended to increase with the duration of administration. The isolated bacteria were comparable between the patients already treated with penicillins and cephems. In the patients treated with aminoglycosides, macrolides, and quinolones, P. aeruginosa was most frequently isolated (33.3 to 40.0%).  相似文献   
83.
The central and peripheral organization of thoracic visceral and somatic nervous elements was studied by applying dextran amines to the proximal cut ends of the thoracic splanchnic and somatic nerves in Xenopus laevis. Many labeled dorsal root ganglion cells of visceral afferents, and all somatic afferents, were located in a single ganglion of one spinal segment, and the two types of cells were distributed topographically within the ganglion. The labeled sympathetic preganglionic neurons were located predominantly in the same area of the thoracic spinal gray as in other frogs and in mammals. The labeled visceral afferents projected to Lissauer's tract and the dorsal funiculus. The visceral fibers of the tract ascended to the level of the subcerebellar area, supplying collateral branches to the lateral one-third of the dorsal horn and to the area of brainstem nuclei, including lateral cervical and descending trigeminal nucleus, and descended to the filum terminale. The visceral fibers of the dorsal funiculus were distributed to the dorsal column nucleus and the solitary tract. A similar longitudinal projection was also seen in the somatic afferents. The dual central pathway of thoracic primary afferents in the anuran spinal cord is a property held in common with mammals, but the widespread rostrocaudal projection through Lissauer's tract may be a characteristic of the anuran central nervous system. In frogs, the direct transmission of primary afferent information to an extremely wide area of the central nervous system may be important for prompt assessment of environmental factors and control of body functions.  相似文献   
84.
Generation of free radical and/or active oxygen by light or laser irradiation of hydrogen peroxide (H2O2) or sodium hypochlorite (NaClO), which have been used for tooth whitening or root canal irrigation, was investigated using electron spin resonance spectroscopy combined with a spin-trapping technique. When H2O2 was exposed to light or laser radiation, the amount of hydroxyl radical generated changed according to the concentration of H2O2 and irradiation time. The amount of 5,5-dimethyl-1-pyrrolidone-(2)-oxyl-(1) (DMPO-X) also changed in accordance with irradiation time. The amounts of hydroxyl radical generated from H2O2 after irradiation were in the order: plasma lamp > halogen lamp > He-Ne laser > Yellow He-Ne laser. On the other hand, the amounts of DMPO-X generated from NaClO after irradiation were in the order: plasma lamp > Yellow He-Ne laser > halogen lamp > He-Ne laser.  相似文献   
85.
86.
In the present study, to clarify whether inhibin affects follicle-stimulating hormone (FSH) secretion in the recrudescence of the male golden hamster, we used a recently developed specific enzyme-linked immunosorbent assay (ELISA) in order to measure 2 forms of inhibin molecules: inhibin B and inhibin pro-alphaC. In addition, we used the radioimmunoassay (RIA) to measure immunoreactive (ir-)inhibin, FSH, luteinizing hormone (LH), and testosterone. And finally, we used the proliferating cell nuclear antigen (PCNA) and computer-assisted sperm motion analysis (CASA) methods to ascertain how well spermatogenesis and sperm motility recover from the photoinhibition caused by exposure to a short-day (SD; 10-hour light: 14-hour dark) photoperiod. Animals were exposed to SD for 15 weeks, and then their testes were checked carefully and found to be completely regressed. Thereafter, those animals were transported to a long-day (LD; 14-hour light: 10-hour dark) photoperiod. Sampling was carried out at weeks 0 (exposed SD 15 weeks), 1, 2, 4, 6, 8, and 10. Plasma FSH rapidly increased and reached peak levels 2 weeks after transferral to the LD photoperiod and then declined to normal LD levels at week 6. Circulating ir-inhibin, inhibin B, and inhibin pro-alphaC rose to normal LD levels by week 4. A highly significant inverse correlation was observed between plasma FSH and inhibin B but not between FSH and either ir-inhibin or inhibin pro-alphaC. Plasma testosterone recovered to normal LD levels within 1 week. Sperm motility parameters were low until week 2 and recovered to normal LD levels from weeks 4 to 10. PCNA-labeled cells were confined to the spermatogenic cells of the seminiferous tubules, though Leydig and Sertoli cell nuclei were never stained for PCNA during the period studied. The number of pachytene spermatocytes and the diameter of seminiferous tubules increased in a time-dependent manner after transferral from SD to LD. In conclusion, these results suggest that 1) secretion of inhibin B may be stimulated by an early rise in FSH; 2) inhibin B suppresses FSH secretion from weeks 2 to 10, after transferral to the LD photoperiod; and 3) testes recrudescence is based on the increase in the number of sperm cells instead of the increase in the number of Sertoli and Leydig cells of the male golden hamster.  相似文献   
87.
A cross-sectional questionnaire study was carried out on nursery school (NS) teachers in public nursery schools in N city in Japan to determine the magnitude of associations of probable risk factors with neck, shoulder, and arm pain, adjusting for potential confounders in logistic regression models. Of 1438 subjects, responded to the questionnaire, 959 NS teachers in charge of a separate or mixed group of children were subjected to analyses. Prevalence of neck and/or shoulder pain was 33.6%-35.4% in NS teachers in charge of children aged 0, 0-1, 4, and 5 in contrast to 25.0-29.8% in those in charge of children aged 1,2, and 3. The prevalence of neck/shoulder pain tended to increase with the length of employment in all groups classified according to the age of children under care. In a logistic regression model that simultaneously adjusted demographic and personal variables, length of employment and care for children aged 0 in the workplace were found significantly associated with musculoskeletal pain. In further logistic models, pain in the neck/shoulders and arms had associations with some specific variables: care for children aged 0, holding/lifting a child/material, overwork, and poorly supported job situations. The odds ratios for those variables varied from 1.37 to 2.41. This results suggest that pain in the neck/shoulders and arms is induced by a wide variety of risk factors in NS teachers that include high physical workload, long working hours, job demand-support imbalance, and cumulative influence of workloads.  相似文献   
88.
Following a transient ischemic insult there is a marked increase in free radical (FR) production within the first 10-15 min of reperfusion and again at the peak of the inflammatory process. Hypothermia decreases lipid peroxidation following global ischemia, raising the possibility that it may act by reducing FR production early on and by maintaining or increasing endogenous antioxidant systems. By means of FR fluorescence, Western blot, immunohistochemistry, and enzymatic assay, we studied the effects of mild hypothermia on superoxide (O(-*)(2)) anion production, superoxide dismutase SOD expression, and activity following focal cerebral ischemia in rats. Mild hypothermia significantly reduced O(-*)(2) generation in the ischemic penumbra and corresponding contralateral region, but did not alter the bilateral SOD expression. SOD enzymatic activity in the ischemic core was slightly reduced in hypothermia-treated animals compared with normothermic controls. Our results suggest that the neuroprotective effect of mild hypothermia may be due, in part, to a reduction in neuronal and endothelial O(-*)(2) production during early reperfusion.  相似文献   
89.
Association between clinical characteristics and types of the tau gene mutation has been observed in frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). P301L mutation seldom causes parkinsonism as a leading symptom; instead it usually causes personality changes with aggressiveness and disinhibition. We experienced two patients of FTDP-17 from separate families (designated as patient 1 from family 1 and patient 2 from family 2). They had P301L mutation in common. However, their phenotypes were distinct from each other. Aggressive behaviors and disinhibition were the main symptoms in patient 1, whereas parkinsonism was the most prominent feature in patient 2. Their genotypes of the tau gene were different at three sites, i. e. in exon 6, in intron segment before exon 10, and in exon 13, though they do not bring amino acid change. Patient 1 had more prevalent C/C, C/C, and rare T/C respectively. Patient 2 had less prevalent T/T, A/A, and more prevalent T/T respectively. These findings suggest two things. Firstly, they do not share a common founder for P301L mutation. Secondly, either of the two less prevalent genotypes observed in patient 2 may be the factor to modify the phenotype of P301L mutation into those unusual clinical features with prominent parkinsonism. Accumulation of information as to phenotype-genotype association will settle this hypothesis. Received: 7 May 2001, Received in revised form: 23 October 2001, Accepted: 22 November 2001  相似文献   
90.
Factor VIII (FVIII) inhibitor alloantibodies react with the A2, C2, or A3-CI domains of FVIII and inactivate FVIII activity. We recently demonstrated that an anti-C2 monoclonal antibody with a Val2248-Gly2285 epitope, inhibited factor Xa (FXa)-catalyzed FVIII activation, and that a FXa binding site for FVIII was located within residues Thr2253-Gln2270. In this study, we investigated whether anti-C2 alloantibodies inhibit FXa-catalyzed FVIII activation. Anti-C2 alloantibodies from four patients inhibited FVIII activation by FXa in one-stage clotting assay. Furthermore, analysis by SDS-PAGE showed that all alloantibodies inhibited FVIII proteolytic cleavage by FXa independently of phospholipid. To confirm direct inhibition of FVIII and FXa interaction, we examined the effect of alloantibodies on FVIII binding to anhydro-FXa, a catalytically inactive FXa, in ELISA. All alloantibodies and C2-affinity purified F(ab)'2 preparations inhibited FVIII binding to anhydro-FXa dose-dependently. Our results revealed a new inhibitory mechanism of FVIII, mediated by inhibition of FXa in the presence of anti-C2 alloantibodies.  相似文献   
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