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31.
We examined the effect of endobronchial (EB) or whole-lung (WL) challenge with ragweed or Timothy grass extract on alveolar macrophage (AM) activation. Expression of 17 constitutive activation markers on AM was examined by flow cytometry. Late-phase bronchial obstruction was greater after WL challenge, while changes in bronchoalveolar lavage cytology (eosinophil accumulation) were greater after EB challenge. After EB challenge, levels of 10 of 17 markers (CD11a, CD11b, CD14, CD18, CD23, CD32, CD63, CD64, HLA-class I, and HLA-DR) were significantly increased (by 33-234%, P < 0.05). Six markers (CD16, CD29, CD33, CD35, CD44, CD71, and HLA-DQ) remained unchanged. Levels of seven markers following EB challenge (CD14, CD16, CD18, CD29, CD32, HLA-class I, and HLA DQ) correlated with airway sensitivity to methacholine. WL challenge only increased expression of HLA-class I. The different results obtained with the two challenge methods probably depend on higher local concentrations of allergen in the EB challenge. We suggest that activation of AM occurs following EB challenge with antigen in asthmatics.  相似文献   
32.
The present experiment evaluated the ability of rats with lesions in the thalamic mediodorsal nucleus (MD) to perform a task which differentiates between "reference" and "working" memory. In this task, only four of the arms of an 8-arm radial maze were baited, and animals were to restrict their entries to arms which were baited and to avoid never-baited arms. Despite several postoperative acquisition trials, rats with MD lesions did not acquire the task to a degree comparable to control subjects. Subjects with lesions continued to enter never-baited arms (reference memory errors) and to reenter baited arms (working memory errors). Given the lack of specificity in the behavioural impairment, the reference-working memory distinction seems to be an inappropriate one for characterizing the MD lesion deficit in rats. This deficit may involve an inability to use environmental stimuli to distinguish among arms of the maze, or an alteration in motor mechanisms.  相似文献   
33.
目的;探讨手术治疗胸椎结核的更好方法。方法;自1990年以来,对21例胸椎结核导致椎柱不稳的患者,应用病灶清除,哈氏棒内固定,椎间及椎板植骨的手术方法。本组平均33.2岁。胸7椎体6例,胸8椎体8例,胸10椎体7例,椎体压缩〈1/2椎体高度13例,〉1/2椎体高度8例,并不全瘫14例。手术中先行病灶清除,然后哈氏棒内固一,撑开后再次清除病灶,取肋骨和髂骨行椎间及椎板上植骨。术后化疗12~15月。结  相似文献   
34.
Over the past three decades, the long-term care community has seen continual increases in the complexity and sophistication of management information systems. These changes have been brought about by the ever-increasing demands on owners and managers to provide accurate and timely data to both regulators and financial investors. The evolution of these systems has increased rapidly in recent years as the nation attempts to reinvent the funding mechanisms for long-term care.  相似文献   
35.
All rugby and soccer players presenting to the Accident & Emergency department during the football season 1992-1993 (a total of 871) were prospectively studied to compare the injuries sustained in the two sports. The nature and site of injury, treatment required, age, fitness, experience and position of the player, situation giving rise to injury, and medical attention at the grounds were all analysed. The results show that rugby and soccer players had the same number of injuries, and while there were some differences in the nature of the injuries, there was no difference in overall severity. Rugby flankers and soccer goalkeepers are particularly at risk. Competitive matches produce more injuries than training sessions. Experience or fitness did not appear to be a factor and 45% of rugby injuries and 15% of soccer injuries were from school matches. Law changes (e.g. the rugby scrum and the use of gum-shields) have reduced some injuries, but other areas (e.g. jumping for the ball in soccer, rucks and mauls in rugby) also warrant consideration. There was one death, but no spinal cord injuries. Medical attention at the grounds was limited. Rugby injuries, therefore, do not appear to be more numerous or severe than soccer injuries. Law changes have been of benefit but they need to be enforced and perhaps more should be considered. Medical attention at sports grounds could be improved and Registers of injuries kept by the sporting bodies would be of benefit.  相似文献   
36.
A new multidimensional movement analysis system was used to record limb tremor over six degrees-of-freedom, and signal processing techniques were explored to develop a suitable classification method to distinguish between different types of tremor. The specific aims were to investigate the ability of the system to screen for differences between normal subjects and a group of neurological patients, and then to differentiate between three diagnostic groups of patients.

Postural tremor at the hand was recorded in normal subjects (n=24) and patients with essential tremor (n=21), multiple sclerosis (n=17) and parkinsonism (n=19). Data were collected using a 3Space Fastrak® (Polhemus, Inc.) over six degrees-of-freedom (three translational directions and three rotations). Spectral estimates produced measures of tremor frequency and amplitude. Mathematical models of the data, using autoregressive modelling and K-nearest neighbour classification, produced parameters used to classify, (1) the normal subjects and 24 patients (using the three rotational movements), and (2) the three patient groups (using all six movement directions). Results were given in terms of the probability of each subject belonging to the groups being classified.

Tremor frequency and amplitude showed large overlap between the groups. The screening classification produced high probabilities of correctly classifying normal subjects (>70%) and patients (>70%). The diagnostic classification produced clear differences between the patient groups (60% for essential tremor, 80% for multiple sclerosis and 60% for parkinsonism).

The ability of this assessment technique to distinguish between postural tremor in normal subjects and neurological patients suggests that it could be developed as a screening tool. Classification of tremors between the patients groups, with a high degree of sensitivity, indicates the potential for further development of the system as a diagnostic aid.  相似文献   

37.
38.
BACKGROUND: Valid clinical guidelines can be effective in improving patient care. Genital Chlamydia trachomatis infection is the commonest curable sexually transmitted disease (STD) in England and Wales and is an important cause of pelvic inflammatory disease (PID), tubal infertility and ectopic pregnancy. No published guidelines exist on managing genital chlamydial infection in British general practice. OBJECTIVE: We aimed to develop valid guidelines for the management of genital chlamydial infection for use in British general practice. METHODS: A district-wide postal questionnaire survey was used to document current clinical practice. A critical review of the evidence concerning the management of genital chlamydial infection as it relates to British general practice was performed. The information gained from the critical review and survey was used to develop evidence-based guidelines within a multidisciplinary guideline recommendation group. RESULTS: The guidelines covered the diagnosis, investigation, drug treatment and referral of adult male and female patients with genital chlamydial infection in general practice. CONCLUSION: Valid guidelines for the management of genital chlamydial infection have been developed for use in British general practice. Appropriate dissemination and implementation of the guidelines should lead to earlier detection and treatment of men and women with chlamydial infection and thereby reduce the incidence of PID, tubal infertility and ectopic pregnancy in women.  相似文献   
39.
We show that a portion of the TM2 domain regulates the sensitivity of beta subunit-containing rat neuronal nicotinic AChR to the ganglionic blocker mecamylamine, such that the substitution of 4 amino acids of the muscle beta subunit sequence into the neuronal beta4 sequence decreases the potency of mecamylamine by a factor of 200 and eliminates any long-term effects of this drug on receptor function. The same exchange of sequence that decreases inhibition by mecamylamine produces a comparable potentiation of long-term inhibition by nicotine. Inhibition by mecamylamine is voltage-dependent, suggesting a direct interaction of mecamylamine with sequence elements within the membrane field. We have previously shown that sensitivity to TMP (tetramethylpiperidine) inhibitors is controlled by the same sequence elements that determine mecamylamine sensitivity. However, inhibition by bis-TMP compounds is independent of voltage. Our experiments did not show any influence of voltage on the inhibition of chimeric receptors by nicotine, suggesting that the inhibitory effects of nicotine are mediated by binding to a site outside the membrane's electric field. An analysis of point mutations indicates that the residues at the 6' position within the beta subunit TM2 domain may be important for determining the effects of both mecamylamine and nicotine in a reciprocal manner. Single mutations at the 10' position are not sufficient to produce effects, but 6' 10' double mutants show more effect than do the 6' single mutants.  相似文献   
40.
Novel 3-substituted quinuclidine inhibitors of cholesterol biosynthesis are reported. Compounds were optimized against oxidosqualene cyclase-lanosterol synthase (OSC) inhibition in vivo, rather than by the conventional optimization of structure-activity relationship information based on in vitro OSC inhibition. Thus, examination of HPLC lipid profiles from orally dosed rats showed cholesterol biosynthetic intermediates and whether cholesterol levels were reduced. A new substituted quinuclidine pharmacophore 18a-c was rapidly found for the inhibition of OSC, and the most promising inhibitors were validated by the confirmation of potent OSC inhibition. Compound 16 gave an IC50 value of 83 +/- 11 nM for human and an IC50 value of 124 +/- 14 nM, for rat, coupled with oral and selective inhibition of cholesterol biosynthesis derived from OSC inhibition (rat, ED50 = 1.3 +/- 0.7 mg/kg, n = 5; marmoset, 15 mg/kg dose, n = 3, caused complete inhibition). These 3-substituted quinuclidines, which were derived from a quinuclidine series previously known to inhibit cholesterol biosynthesis at the squalene synthase step, may afford a novel series of hypocholesterolemic agents acting by the inhibition of OSC.  相似文献   
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