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11.
To determine the onset time, duration of action and recovery time of high-dose vecuronium, 70 patients were assigned to receive either 100, 150, 200 or 300 micrograms.kg-1 of vecuronium for muscle relaxation during elective surgery. Neuromuscular blockade was continuously quantitated by recording the EMG response to stimulation of the ulnar nerve. The onset time from the time of vecuronium administration to maximum blockade decreased from 4.6 +/- 1.1 to 2.4 +/- 0.5 min when the vecuronium doses increased from 100 to 300 micrograms.kg-1. Significant differences were observed in the onset time between the 100 micrograms.kg-1 dose and the other dose groups. Endotracheal intubating conditions were excellent in all patients except 3 in the 100 micrograms.kg-1 dose group. The duration of action from the time of injection to 25% recovery increased from 32 +/- 9 to 138 +/- 48 min in a dose dependent manner. The duration of action after increment doses of 40 or 50 micrograms.kg-1 up to 25% recovery of T1 did not vary significantly within the same dose group. With an initial dose of 150 micrograms.kg-1 and subsequent increment doses of 50 micrograms.kg-1 or less, the duration of action remained constant. The recovery time from 25 to 75% recovery was within 11 minutes when antagonists were administered. High-dose vecuronium may, therefore, be a useful alternative to SCC, when a rapid onset is required and to pancuronium, when a rapid recovery from neuromuscular blockade is requested.  相似文献   
12.
13.
Initiation and propagation reaction mechanisms of the anionic polymerization of hexafluoro-1,3-butadiene (HEBD) were investigated. The initiation reaction with caesium tert-butoxide was found to be completed within 5 min although the reactions were carried out at a much lower temperature than that of the polymerization reaction. The initiation reaction was, therefore, inferred to take place in an anionic fashion by adding the tert-butoxide anion to HFBD. In order to clarify the propagation reaction mechanism of HFBD which yielded a polymer with a polyvinylene structure, the polymerization reactivity of HFBD and hexafluoro-2-butyne (HFBY), the isomerization of HFBD to HFBY, and the structural difference between poly(HFBD) and poly(HFBY) were discussed. In spite of the low yield of HFBY by the isomerization reaction under polymerization conditions, higher yields of poly(HFBD) were obtained. Judging from the X-ray analysis which showed that poly(HFBD) was highly crystalline and poly(HFBY) was amorphous, poly(HFBD) might not be produced by polymerization of HFBY. An addition reaction of the propagating anion to the carbon-2 of the HFBD monomer followed by isomerization at the propagating living end to yield poly[1,2-bis(trifluoromethyl)vinylene] is proposed.  相似文献   
14.
Temperature-dependent ESR spectra of Cu2+-Cu2+ pairs in ethylene/methacrylic acid copolymer neutralized with Cu(II) were reexamined in detail. The resonance positions and the linewidths of one of the ESR fine-structure lines showed thermal distension of the Cu2+-Cu2+ distance, and the slopes in the temperature variations changed at the temperature associated with melting of the polymer crystallites. No meaningful anomalies were observed around the temperature at which the preceding endothermic transition takes place. In this transition, the Cu2+-Cu2+ pairs seems to enter a disordered state, keeping almost the same paired structure. In contrast to this irreversible order-disorder transition, the melting process in the most part of the polyethylene crystallite phases starts to impose stress upon the Cu2+-Cu2+ pairs, accompanying the slope changes of the ESR parameters. These reversible variations with remarkable thermal hysteresis are compatible with the DSC analyses.  相似文献   
15.
The present study was conducted to determine the manner in which monocytes increase mesangial matrices, particularly glycosaminoglycans (GAGs) which interact with various other matrix components such as collagens, laminin, fibronectin and lipoproteins. A supernatant of human peripheral blood monocyte cultures activated by lipopolysaccharide (LPS) contains stimulating factors for glycosaminoglycan synthesis in rat mesangial cells (MCs). The culture supernatant in this study was concentrated and fractionated by gel chromatography and the GAG-stimulatory factor was found to have a molecular weight of 10-17 kD. This factor was shown to be present in fractions different from that of IL-1. Gel and ion-exchange chromatography studies of GAGs synthesized by MCs indicated the elution patterns of GAGs in the presence and absence of the monocyte culture supernatant to be essentially the same. Local infiltration of monocytes into the glomerulus, often seen in various types of glomerular injury, may be an important factor in the accumulation of the mesangial matrix.  相似文献   
16.
The spread of Aujeszky's disease virus (ADV) from nasal mucosa via the olfactory pathway was studied in HPCD pigs. ADV antigen was detected in the epithelial cells, nasal gland cells, olfactory nerve cells and peripheral nerve fibres in the nasal cavity and in neuroglial cells in the olfactory bulb. Results indicate that the olfactory pathway is one of the most important neuronal pathways of ADV infection in pigs.  相似文献   
17.
An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500–600 ml watery sputum a day, loss of weight, and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregulary-shaped cytoplasmic vacuoles suggestive of mucin.  相似文献   
18.
Pigs exposed to fluctuating temperatures (high, 30 +/- 2 degrees C; low, 4 +/- 1 degrees C) were intranasally inoculated with Aujeszky's disease virus (ADV). ADV-infected pigs, exposed to the fluctuating temperatures, showed severe clinical signs and ADV in the nasal secretions persisted longer than in the ADV-infected control pigs kept at the normal temperature (20 +/- 2 degrees C). High concentrations of ADV were isolated from nasal secretions on the 1st day after inoculation of the virus. Pathologically, all ADV-infected pigs had non-suppurative encephalitis and trigeminal ganglionitis. The lesions were more widely distributed in pigs exposed to fluctuating temperatures than in infected control pigs. Two infected pigs given the stress had severe malacic foci in the frontal lobe and four of them had prominent interstitial pneumonia. In the pigs exposed to fluctuating temperatures, a significant number of immunoglobulin-containing cells, especially IgM-containing cells, did not respond to ADV infection. A significant (P < 0.01) difference in the number of IgG- and IgM-containing cells was observed between the ADV-infected pigs exposed to the fluctuating temperature and ADV-infected control pigs, respectively. These results demonstrated that the stress of fluctuating temperatures enhanced the susceptibility to ADV infection.  相似文献   
19.
The number of complement receptor for C3b (CR1) molecules in erythrocytes from patients with renal diseases was measured by an immunoradiometric assay using monoclonal antibodies against CR1. IgA nephritis patients with high serum creatinine value (Scr) showed markedly elevated levels of CR1, whereas patients with normal Scr had normal CR1 levels. A similar increase in CR1 number was observed in membranoproliferative glomerular nephritis with high Scr. CR1 of these patients functioned normally as a cofactor of C3b inactivator in cleaving immune complex-bound C3b. In contrast, a high frequency (5/6) of negative staining of glomerular CR1 was observed in IgA nephritis patients with high Scr by immunofluorescence study. We postulate that the disease-associated, acquired factors at least in part contribute to the abnormal expression of CR1: elevated levels in erythrocytes and defective expression on glomeruli.  相似文献   
20.
We found elevated levels of interleukin-8 in pleural fluid samples from patients with pleural effusion and with a sustained fibrotic change of the lung due to Mycoplasma pneumoniae infection. This result suggests a critical role of interleukin-8 in the pathogenesis of a certain type of pulmonary disease caused by M. pneumoniae.  相似文献   
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