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101.
V. Houdouin S. Bonacorsi P. Bidet E. Bingen 《Clinical microbiology and infection》2007,13(12):1207-1210
The susceptibility of 136 Escherichia coli isolates from cases of neonatal meningitis to amoxycillin, ceftriaxone, nalidixic acid, ciprofloxacin and gentamicin was determined in relation to the carriage of virulence factors and phylogenetic group. Only amoxycillin and nalidixic acid resistance was observed (40% and 3%, respectively). Nalidixic acid resistance alone was associated with non-virulent phylogenetic group A (50% vs. 6% of susceptible isolates; p 0.03). No difference in virulence was observed between two representative nalidixic acid-susceptible virulent group B2 isolates and their nalidixic acid-resistant derivatives in a rat model of neonatal meningitis, suggesting that nalidixic acid resistance does not affect the virulence of E. coli strains causing meningitis. 相似文献
102.
Iwasaki M Kobayashi K Suzuki H Anan K Ohno S Geng Z Li G Inoko H 《Tissue antigens》2000,56(2):136-142
Genetic polymorphism in the ABO blood group gene of Han, Kazak and Uygur populations inhabiting the most northwestern part of China was investigated using polymerase chain reaction-based techniques. The present study enrolled 43 healthy unrelated Han, 37 Kazak and 59 Uygur volunteers. The allele in A1 blood group is distinguished A0101 and A0102 in difference of nucleotide position 467. The A0101 allele is more frequent in Caucasian and the A0102 allele is characteristic in Mongoloid. It must be notable that A0201 in the A2 group (with a single base deletion at nucleotides 1059 to 1061) which was characteristic of Caucasian was observed in Kazak and Uygur populations but not in Han. Further, 00201 (with no nucleotide deletion at 261 and three nucleotide differences), which is frequent in different races including Caucasian except for Mongoloid, was detected also in Kazak and Uygur populations. The frequencies of B0101 in Kazak, Uygur and Han were comparable to those of other Asian populations but higher than those of Caucasian populations. Collectively, these results reveal that the allele frequencies of Kazak and Uygur at the ABO blood group locus are an intermediate between those of Mongoloid and Caucasian, suggesting the admixed feature of Kazak and Uygur with Mongoloid and Caucasian. 相似文献
103.
Struzik L Duffin J Vermani M Hegadoren K Katzman MA 《Respiratory physiology & neurobiology》2002,133(3):183-195
Klein (Arch. Gen. Psychiatry 50, 306-317, 1993) suggests that panic attacks are the result of a defective 'suffocation alarm' threshold that presents with carbon dioxide (CO(2)) hypersensitivity, exaggerated ventilatory response and panic in panic disorder (PD) patients. Serotonergic deficiencies enhance this ventilatory response in PD patients, as per 'suffocation alarm' theory predictions, suggesting that serotonin (5-HT) normalizes the ventilatory response. Other research supports a serotonin system-mediated stimulation of ventilation. Knowledge of 5-HT's role on ventilatory output and its neurophysiological sources impacts on the 'suffocation alarm' theory validity and predictive value. We used tryptophan depletion (TRP-) in concert with a modified Read rebreathing test to determine the effect of deficient serotonergic modulation on the central and peripheral chemoreflex threshold and sensitivity of response to CO(2) in 11 healthy men. TRP- did not affect central or peripheral chemoreflex threshold or sensitivity of response to CO(2). However, basal ventilation was significantly elevated during TRP-. In contrast to 'suffocation alarm' theory predictions, decreased 5-HT neurotransmission does not significantly affect the respiratory chemoreflex response to CO(2), impacting on non-chemoreflex drives to breathe. Panic associated respiratory abnormalities may be related to defective 5-HT modulation of non-chemoreflex drives to breathe, unrelated to any respiratory chemoreflex abnormality. 相似文献
104.
105.
Alcohol and the Psychophysiological Detection of Deception 总被引:1,自引:0,他引:1
Psychophysiological detection of deception examinations were conducted on 40 subjects. Of these, 32 were “guilty” of a mock crime and 8 were innocent. Sixteen guilty subjects committed the crime while intoxicated and the remaining 16 committed the crime sober. These two groups of guilty subjects were subdivided such that half of each group was examined with the polygraph while intoxicated and the other half was examined while sober. Two questioning techniques were used in the examination, a Control Question Test and the Guilty Knowledge Test. Measures of skin resistance, heart rate and respiration were recorded. The principal findings were that alcohol intoxication during the crime reduced detectability with detection scores derived from the measurement of skin resistance responses on the Control Question Test and on the Guilty Knowledge Test. The analyses of guilt/innocent classifications, based on the detection scores, showed these classifications to be affected by alcohol intoxication. 相似文献
106.
107.
108.
K. D. Kniffki S. Mense R. F. Schmidt 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1978,31(4):511-522
Summary In an attempt to differentiate between nociceptive group IV muscle receptors and ergoceptive ones, the discharges of single group IV fibres from skeletal muscle in response to local pressure, sustained stretch, repetitive contraction and intra-arterial injections of bradykinin, 5-hydroxytryptamine (5-HT), potassium, phosphate, and lactate were studied in anaesthetized cats.Of the 75 fibres of the study, 5 units were activated by sustained stretch, the responses occurring with a delay. These stretch-sensitive units could not be activated by local pressure or muscular contraction. Thirteen group IV afferents raised their discharge frequency during repetitive contractions. Some of the units responded immediately with the onset of the contractions, whereas the others showed a pronounced delay.Forty-six units were tested with all or most of the above mechanical and chemical stimuli. In 32 afferents a response to at least one of the stimuli was present. Taking only these units into account, several groups of receptors could be distinguished by their different response combinations. One group was activated by pain-producing substances, but not by muscular activity and thus showed nociceptive properties. Another group showed a raised activity during muscular contractions but did not respond to the algesic agents bradykinin and 5-HT. Units belonging to this group might serve as ergoceptors. The borderline between the two groups was not sharp, a considerable number of group IV afferents was found which had both nociceptive and ergoceptive properties. 相似文献
109.
产前血型IgG抗体水平的检测及其临床意义 总被引:3,自引:0,他引:3
目的探讨ABO血型不合孕妇的产前IgG抗体水平,了解IgG抗体效价异常在孕妇中所占比率及临床意义,为预防及诊治新生儿溶血病(HDN)采取有效的防治措施。方法用抗人球蛋白试管凝集法进行IgG抗A或抗B的ABO血型抗体效价检测。结果910例孕妇中,血清效价大于64者有108例,异常检出率为11.9%。IgG抗A效价大于64者有64例,检测率为11.8%;检测IgG抗B效价大于64者有54例,检测率为14.1%。讨论妊娠中IgG抗体效价与新生儿溶血密切相关,ABO血型不合的孕妇应及时作产前血清学的检测,可预防新生儿溶血病的发生及减轻胎儿受害的程度。 相似文献
110.
Dr. S. M. Highstein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1973,17(3):285-300
Summary Intracellular and extracellular responses were recorded with glass micro-electrodes from motoneurons in the IIIrd and IVth cranial nuclei of anesthesized rabbits. Five subgroups of neurons innervating the superior rectus (SR), inferior oblique (IO), inferior rectus (IR), medial rectus (MR), and superior oblique (IVth) extraocular muscles were identified by their antidromic activation from the branches of the IIIrd and IVth cranial nerves. The relative positions of the subgroups thus determined were consistent with the histological data on the rabbit. In the SR, IO, IR, and IVth subgroups the effects of ipsilateral VIIIth nerve stimulation were inhibitory, producing disynaptic IPSPs, while the effects of contralateral VIIIth nerve stimulation were excitatory, producing disynaptic EPSPs. In the MR subgroup, however, a mixture of EPSPs and IPSPs was produced by VIIIth nerve stimulation: this was particularly clear on the ipsilateral side. Sites relaying these VIIIth nerve effects to each of the five subgroups were explored by direct stimulation of various brain stem sites. Stimulation of the superior vestibular nucleus (SV) produced IPSPs monosynaptically in all five subgroups on the ipsilateral side as well as in the contralateral MR subgroup. Stimulation of the medial vestibular nucleus (MV) produced EPSPs monosynaptically in all of the five subgroups on the contralateral side as well as in the ipsilateral MR subgroup. Stimulation of the brachium conjunctivum (BC) also produced EPSPs monosynaptically in the contralateral SR, IO, and IR subgroups. Further, while the recording electrode was placed within each of the five subgroups to observe the extracellular potentials corresponding to the intracellularly recorded IPSPs and EPSPs, the medulla and cerebellum were systematically tracked with a monopolar stimulating electrode. It was thus confirmed that the SV is the sole inhibitory relay site, while excitation is relayed by both the MV and the BC. The origin of the BC pathway was traced to the Y-Group for the IO, to the lateral nucleus of the cerebellum (LN) for the IR, and to both the Y-Group and the LN for the SR subgroup. 相似文献