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11.
12.
The pattern of fibre degeneration in the lateral corticospinal tract (LCST) was studied in a case of Friedreich's ataxia (FA). There was preferential involvement of the lateral area of the LCST in the cervical spinal cord. More caudally, the degeneration involved the entire area of the LCST and did not reveal a medial to lateral gradient of involvement. We suggest that this distinctive pattern of tract degeneration is a consequence of the somatotopic organization of the LCST, with the dying-back degeneration preferentially affecting those LCST fibers that extend to the lumbo-sacral spinal cord. This pattern of tract degeneration may be a useful morphological marker of dying-back degeneration in corticospinal tracts. 相似文献
13.
J. R. Zahar M. Lecuit E. Carbonnelle F. Ribadeau-Dumas X. Nassif O. Lortholary 《Clinical microbiology and infection》2007,13(3):219-221
Until recently, most reported cases of bacteraemia caused by multidrug-resistant strains of Enterobacteriacae producing an extended-spectrum beta-lactamase (ESBL) in Europe have been nosocomial in origin. However, increasing numbers of reports of community-acquired bacteraemia and urinary tract infection caused by ESBL-producing microorganisms suggest that the geographical origin of patients should be taken into account as a risk-factor for possible ESBL production. Early identification of patients at high-risk of infection with ESBL-producing microorganisms, based on their geographical origin and travel history, should help to optimise initial antibiotic treatment strategies for severe urinary tract infections in Europe. 相似文献
14.
E MOLKE JENSEN K. A. THIESSEN AA. CHRISTENSEN 《Acta anaesthesiologica Scandinavica》1986,30(2):109-110
The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs. 相似文献
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16.
Adherence is a major virulence factor in the complex pathogenesis of urinary tract infections (UTI). Colonization of the urinary tract and subsequent spread of infection ascending to the kidneys depends not only on the expression of adhesins by bacteria but also on the presence of host factors which may either contribute to or inhibit infection. The presence of certain types of adhesins expressed by the bacteria and their interactions with epithelial cells play a role in determining where bacteria localize in the urinary tract, the kind and severity of symptoms and how the disease progresses. The knowledge of the molecular mechanisms underlying adherence may be useful for epidemiological research in the pathogenesis of UTI, for the diagnosis of different types of UTI and, in some cases, for prognosis. Furthermore, attachment to epithelia is a promising target for developing new methods in prophylaxis and therapy. 相似文献
17.
BACKGROUND: Carbon monoxide (CO) has emerged as an endogenously produced gaseous mediator known to be involved in bronchial smooth muscle regulation. Increased amounts of CO have been found in exhaled air during asthma and lower airway inflammation. Recently CO has been shown to be produced in the nasal airways, but there are no reports of altered CO levels in nasal airways during inflammation. OBJECTIVE: This study was designed to investigate if CO levels increase in the human nasal airways during inflammatory conditions, such as allergy and upper airway respiratory tract infection (URTI). METHODS: CO was sampled separately from the upper and lower airways of 13 healthy control subjects, six patients with a history of allergic rhinitis and six patients with URTI. RESULTS: Nasal CO levels were increased in subjects with allergic rhinitis, compared to healthy controls (2.07 +/- 0.15 ppm, n = 6 and 1.62 +/- 0.08 ppm, n = 13, respectively, P < 0.01). CO levels were also increased in patients with URTI, compared to the same controls (1.92 +/- 0.09 ppm, n = 6, P < 0.05). Normal levels of CO were found in air from the lower airways among subjects with allergic rhinitis, whereas corresponding levels in the URTI patients were increased. CONCLUSION: The present data demonstrates that upper airway CO levels increase in parallel with different inflammatory stimuli, such as allergy and infection, suggesting a role for CO as marker or mediator of nasal inflammation. 相似文献
18.
R. Vijayaraghavan M. Schaper R. Thompson M. F. Stock Y. Alarie 《Archives of toxicology》1993,67(7):478-490
A system was developed for exposure of unanesthetized mice to airborne chemicals and for continuous measurement of their breathing pattern prior to, during and following exposure. By measuring inspiratory and expiratory airflows (VI and VE), and integration with time to yield tidal volume (VT), we obtained characteristic modifications to the normal breathing pattern. These permitted recognition that a specific portion of the respiratory tract was affected by the selected airborne chemicals. Following recognition, we also quantitated the degree of effect using one specific measurement in each case. An effect on the upper respiratory tract, induced by the sensory irritant, 2-chlorobenzylchloride, was quantitated by measuring a decrease in respiratory frequency. An effect on the conducting airways, induced by the airway constrictor, carbamylcholine, was quantitated by a decrease in VE at the mid-point of VT. An effect at the alveolar level, induced either by the vagal nerve ending stimulant, propranolol, or by the pulmonary irritant, machining fluid G, was quantitated by an increase in the length of a pause induced at the end of expiration. The system is easy to construct and operate and can be used to rapidly evaluate the effects of airborne chemicals on the respiratory tract. 相似文献
19.
长春地区儿童急性呼吸道感染的病原趋势 总被引:1,自引:0,他引:1
目的:探讨北方地区小儿急性呼吸道感染(ARIs)病原构成特点,为临床诊断及治疗提供依据。方法:采用酶联免疫吸附试验(ELISA)方法,对574例ARIs患儿进行了肺炎支原体(Mp)、沙眼衣原体(CT)、肺炎支原体(CP)、呼吸道合胞病毒(RSV)、腺病毒(Adv)、流感病毒A型(Inf-A)、副流感病毒(PIV)等7种病原同步进行急性期血清特异性抗体IgM检测,同时设立健康对照组。结果:574例患儿共334例检出特异性IgM抗体,阳性率58.2%。按检出频率的高低依次为Mp28.9%(166/574),RSV13.6%(78/574),CP5.9%(34/574),CT4.4%(25/574),Adv3.3%(19/574),Inf-A1.2%(7/574),PIV0.9%(5/574),分别占阳性例数的49.7%(166/334)、23.3%(78/334)、10.2%(34/334)、7.5%(25/334)、5.7%(19/334)、2.1%(7/334)和1.5%(5/334);病原分布具有年龄差别。健康对照组仅检出1例MP-IgM阳性(1.7%)。结论:Mp、RSV及CT为小儿ARI的常见病原。Mp感染率逐渐增高,发病年龄有逐渐变小的趋势。 相似文献
20.
The primary general visceral nucleus in goldfish (Carassius auratus) and catfish (Ictalurus punctatus) is located at the ventroposterior boundary of the vagal gustatory lobe and receives coelomic visceral, but not gustatory inputs. The neuronal tracer horseradish peroxidase (HRP) was employed to visualize sources of input to and ascending projections from the primary general visceral nucleus in these species. In addition, immunocytochemical techniques were utilized to define the cytological divisions within the pontine gustatory-visceral complex. The pontine secondary visceral nuclei in both catfish and goldfish contains numerous somata and fibers immunoreactive for calcitonin gene-related peptide (CGRP). In contrast, the secondary gustatory nuclei are devoid of fibers and cells immunoreactive for CGRP. In both the goldfish and the channel catfish, the primary general visceral nucleus receives input from the vagal gustatory lobe, as well as the medullary reticular formation. In the channel catfish, the primary general visceral nucleus projects bilaterally to the secondary visceral nucleus, which lies rostrolateral to the secondary gustatory nucleus in the dorsal pons. Fibers cross the midline via the rostral part of the isthmic commissure. Injection of HRP into the primary general visceral nucleus of a goldfish labels ascending fibers that project to a secondary visceral nucleus situated ventral, lateral, and rostral to the secondary gustatory complex. In general, the results indicate that general visceral systems ascend in parallel to gustatory systems within the brainstem, and that general visceral but not gustatory nuclei are immunoreactive for the peptide CGRP. 相似文献