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31.
Scanning densitometry and computer-assisted numerical analysis were used to examine restriction endonuclease digest patterns (RDPs) of chromosomal DNA from 26 infecting strains and 44 vaginal isolates of group B beta-haemolytic streptococci (GBS). At the 95% similarity level, HindIII RDPs of serotype Ia and III strains clustered into four and three RDP types, respectively. Nine of 10 strains from neonates with early-onset septicaemia belonged to two particular RDP types (Ia-3 and III-3). In contrast, serotype III GBS strains from meningitis cases were not characterised by particular RDP types. Associations between RDPs and certain phenotypic characteristics were also found.  相似文献   
32.
Nagano H  Mise K  Okuno T  Furusawa I 《Virology》1999,265(2):226-234
Cucumber mosaic cucumovirus (CMV) and brome mosaic bromovirus (BMV) have many similarities, including the three-dimensional structure of virions, genome organizations, and requirement of the coat protein (CP) for cell-to-cell movement. We have shown that a chimeric BMV with the CMV 3a movement protein (MP) gene instead of its own cannot move from cell to cell in Chenopodium quinoa, a common permissive host for both BMV and CMV. Another chimeric BMV was constructed by replacing both MP and CP genes of BMV with those of CMV (MP/CP-chimera) and tested for its infectivity in C. quinoa, to determine whether the CMV CP has some functions required for the CMV MP-mediated cell-to-cell movement and to exhibit functional difference between CPs of BMV and CMV. Cell-to-cell movement of the MP/CP-chimera occurred, and small local lesions were induced on the inoculated leaves. A frameshift mutation introduced in the CMV CP gene of the MP/CP-chimera resulted in a lack of cell-to-cell movement of the chimeric virus. These results indicate that the viral movement mediated by the CMV MP requires its cognate CP. Deletion of the amino-terminal region in CMV CP, which is not obligatory for CMV movement, also abolished cell-to-cell movement of the MP/CP-chimera. This may suggest some differences in cell-to-cell movement of the MP/CP-chimera and CMV. On the other hand, the sole replacement of BMV CP gene with that of CMV abolished viral cell-to-cell movement, suggesting a possibility that the viral movement mediated by the BMV MP may also require its cognate CP. Functional compatibility between MP and CP in viral cell-to-cell movement is discussed.  相似文献   
33.
The effect of evaluative observation on cardiovascular responses was assessed in 20 female undergraduate students. All participants performed a mental arithmetic (MA) task, and a mirror drawing (MD) task, with or without evaluative observation. Heart rate, blood pressure (BP), admittance plethysmography, and task performance were recorded for each task. Both tasks increased blood pressure, but the hemodynamic response patterns were distinct. The MA task induced enhanced cardiac response, whereas the MD task induced a vascular dominant response. Evaluative observation substantially increased BP during both tasks, but it always enhanced cardiac output and reduced total peripheral resistance. The hemodynamic responses changed significantly from vascular dominant to cardiac dominant, particularly during the MD task. The similarity of responses during evaluative and competitive situations is discussed. The significance of interpersonal factors in psychophysiological studies is emphasized.  相似文献   
34.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
35.
The present study was performed to evaluate postoperative hoarseness quantitatively by means of acoustic wave form analysis. Pitch and amplitude perturbation (PPQ, and APQ), and normalized noise energy (NNE) were measured along with the frequency characteristics in 51 adult patients undergoing elective surgery. The normal values for these acoustic parameters were less than 0.5%, less than 2.0%, and less than -10 dB, respectively. Vowel sound "E" was recorded and evaluated before the induction of anesthesia and on the morning of the day after the surgery. PPQ increased from 0.39% to 1.00% (P less than 0.05), APQ increased from 3.34% to 6.62% (P less than 0.05), and NNE increased from -9.19 dB to -4.74 dB (P less than 0.05). Eighteen percent of the patients showed abnormal values in all parameters preoperatively, but 45% of the patients postoperatively (P less than 0.05). These findings suggest that even the short term intubation resulted in the postoperative hoarseness, and this method is a useful and non-invasive bed-side test to evaluate postoperative hoarseness quantitatively.  相似文献   
36.
Summary The effects of morphine-HCl (MOR), methionine-enkephalin (ME) and dynorphin1–13 (DYN) on spinal and spino-bulbo-spinal (SBS) reflexes were studied. Although spinal intrathecal administration of MOR (15g) did not produce any apparent effect on these reflexes, systemically administered MOR (3mg/kg i.v.) reduced the electrical toe stimulation-induced SBS reflex. Furthermore, MOR (3mg/kg i.v.) increased the polysynaptic reflex induced by electrical stimulation of low-threshold dorsal root afferents in intact (non-spinal) rats, but not in spinal rats. Intrathecally administred DYN (0.5 and 5 g) reduced both the electrical toe stimulation-induced spinal and SBS reflexes, while ME (15g) only reduced the SBS reflex. These results indicate the physiological multiplicity of spinal opioid receptors. MOR may affect supraspinal nuclei but not the spinal pathway which possesses MOR-sensitive opioid receptors, whereas ME and DYN affect spinal opioid peptide receptors and modulate the reflex activities in which they participate.  相似文献   
37.
The effect of calcium-balanced heparin (471896, CIBA CORNING) on blood gas and electrolyte analysis was evaluated, by comparing with that of sodium heparin (Na heparin). One ml of whole blood was collected into a syringe, which contained calcium-balance heparin (Ca balanced heparin) or Na heparin. 122 pairs of blood samples obtained from 15 patients were analyzed for Na, K, ionized calcium (Ca(++)), total hemoglobin, pH, P(CO)(2), and P(O)(2) by an automatic blood gas and electrolyte analyzer, CIBA CORNING model 288. There was a significant difference ( P < 0.05) in pH, P(CO)(2), Na, and Ca(++) between the two different groups. Ca(++) concentration was significantly less in Na heparin group than in Ca balanced heparin group, probably due to more chelation of Ca(++) by Na heparin than Ca balanced heparin. The present study suggests that the Ca balanced heparin has minimal effect on the blood gas and electrolyte analysis, and is a suitable anticoagulant for the Ca(++) measurement.  相似文献   
38.
  1. A murine anti-human vWF monoclonal antibody, AJvW-2, was developed that inhibited the interaction between platelet glycoprotein Ib (GPIb) and von Willebrand factor (vWF) during the ristocetin- (IC50=0.7±0.1 μg ml−1) and botrocetin- (IC50=1.8±0.3 μg ml−1) induced aggregation of human platelets.
  2. AJvW-2 inhibited the high shear stress (10.8 N m−2) induced aggregation of human platelets dose-dependently with an IC50=2.4±0.3 μg ml−1, but had no effect on low shear stress induced platelet aggregation (1.2 N m−2) up to 100 μg ml−1.
  3. AJvW-2 also inhibited the high shear stress (5.0 N m−2) induced adhesion of human platelets to collagen I with the same efficacy (IC50=2.4±0.3 μg ml−1), but had no effect at low shear conditions (1.5 N m−2).
  4. AJvW-2 inhibited the botrocetin-induced aggregation of platelets from guinea-pig, rat, rabbit, dog and pig at the same concentration range as human platelets; it likewise also inhibited the high shear stress induced aggregation and adhesion to collagen I of guinea-pig platelets.
  5. AJvW-2 prevented arterial thrombus formation in guinea-pigs at a dose of 100 μg kg−1 without prolonging the template bleeding time, whereas the GPIIb/IIIa antagonist lamifiban mediated inhibition of thrombosis at 1000 μg kg−1 was accompanied by a significant prolongation of the bleeding time.
  6. These results suggest that AJvW-2 is a potent inhibitor of the GPIb-vWF interaction and a potential novel antithrombotic agent with lower bleeding risk than GPIIb/IIIa antagonists.
  相似文献   
39.
40.
The rate of infection with TT virus (TTV), a novel single-strand DNA virus was evaluated and the clinical and laboratory features in affected Japanese medical workers were analysed. TTV DNA was measured in 356 medical workers and in 150 age-matched controls using a seminested polymerase chain reaction. TTV DNA was detected in 62 of 356 medical workers (17.4%). There were no differences in the prevalence of TTV infection between medical workers and controls (18.9%) and in the characteristics of medical workers with TTV infection and medical workers without it, except that the mean age of patients with TTV infection was higher than that of patients without TTV. The medical workers were drawn from three groups: medical doctors, nurses and clinical laboratory technicians. There was no statistically significant difference between the rate of TTV infection in the three groups. These findings suggest that the risk of TTV infection in medical workers is low and not related to liver dysfunction.  相似文献   
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