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1.
During the time from 1982/83 the intracranial pressure was continuously measured from patients who were polytraumatized and also had severe head injuries. In 53% of these cases the first readings could be obtained within 6 hours after the injury and in 33% first after 12 hours. During the time of evaluation this relationship shifted to earlier implantation. From 27% of these patients the intracranial pressure values fell into a range that instigated immediate therapeutical measures. This proves how important it is to have a direct reading from the intracranial pressure as soon as possible after injury. The aspects of therapy by increased intracranial pressure were discussed.  相似文献   
2.
A total of 130 Haemophilus strains, comprising virtually all isolates from Danish and Norwegian cases of Haemophilus meningitis occurring in the period from October 1975 through September 1976, were examined by biochemical and serological means. All isolates were identified as H. influenzae and, except for one noncapsulated strain, possessed a capsule of serotype b. The vast majority of strains (93%) belonged to biotype I, which, in contrast to biotypes II and III, is rarely encountered as a commensal of the upper respiratory tract. This finding is a strong incentive for studies of possible additional virulence factors associated with biotype I organisms. The results are discussed in the light of North American reports, which have suggested changes in the etiology of Haemophilus meningitis.  相似文献   
3.
Bacterial immunoglobulin A1 (IgA1) proteases cleaving IgA1 and secretory IgA1 molecules in the hinge region are believed to be important virulence factors. Previous studies have indicated that IgA of humans, gorillas, and chimpanzees are the exclusive substrates of these enzymes. In a recent study, IgA from the rhesus monkey was found to be susceptible to the IgA1 protease activity of Streptococcus pneumoniae. In an attempt to reproduce this observation, we found that neither five isolates of S. pneumoniae nor other IgA1 protease-producing bacteria representing different cleavage specificities caused cleavage of rhesus monkey IgA. Hence, the rhesus monkey does not appear to be a suitable animal model for studies of IgA1 proteases as virulence factors.  相似文献   
4.
Immunoglobulin A1 (IgA1) proteases may be important virulence factors of certain bacteria involved in the pathogenesis of meningitis, gonorrhea, destructive periodontal diseases, and some other infections affecting mucosal membranes. This study evaluated the antigen-binding activity of free Fab alpha fragments released from human myeloma IgA1 by IgA1 protease from Haemophilus influenzae. Six myeloma proteins with antibody activity against streptolysin O, alpha-staphylolysin, or streptococcal hyaluronidase were used. Complete cleavage of the IgA1 myeloma proteins in the hinge region of the heavy chain did not affect their antigen-binding capacity. The titers of neutralizing activity associated with free Fab alpha fragments were not significantly different from those of the intact IgA1 proteins. The retained antigen-binding capacity of cleaved IgA1 is an important factor in the understanding of how IgA1 proteases may interfere with the immune protection of mucosal membranes.  相似文献   
5.
Initial colonization of teeth in monkeys as related to diet.   总被引:2,自引:4,他引:2       下载免费PDF全文
The initial phases of plaque development on nonretentive tooth surfaces were studied bacteriologically in Macaca irus monkeys fed by stomach tube and provided with various oral supplements. Except for the oral implantation of Streptococcus mutans in some of the animals, the oral flora was not changed prior to the studies. Dental plaque was allowed to develop on initially cleaned tooth surfaces for 3 to 5 h. Plaque samples were collected and cultured on a number of selective and nonselective agar media, and several hundred isolates from each sample were isolated and identified. The numerically predominant organisms in initial plaque were S. mutans, Streptococcus sanguis, and Actinomyces viscosus. Additional organisms regularly found, but usually in smaller numbers, were Streptococcus mitior and a group of fastidious gram-negative rods including Haemophilus species, Eikenella corrodens, and Actinobacillus actinomycetem-comitans. The colonization of S. mutans was dependent on sucrose and occurred at the expense of S. sanguis. In these experiments S. mutans accounted for 25 to 65% of the primary plaque formers. All other species encountered colonized the teeth irrespective of the diet. It is postulated that the early sucrose-dependent establishment of S. mutans directly on the enamel pellicle plays a key role in the development of a cariogenic plaque.  相似文献   
6.
The bacterium Actinobacillus actinomycetemcomitans has been implicated in the pathogenesis of juvenile periodontitis as the etiologic agent on the basis of several lines of circumstantial evidence. A matter of extensive debate is whether A. actinomycetemcomitans is an exogenous contagious pathogen or an opportunistic pathogen that resides in the normal oral microflora. Here we show evidence of a single clone of A. actinomycetemcomitans isolated from multiple patients with juvenile periodontitis in members of families of African origin living in geographically widespread areas. The clone is characterized by a 530-bp deletion in the leukotoxin gene operon, resulting in a significantly increased production of leukotoxin.  相似文献   
7.
Free-roaming camels, especially those crossing national borders, pose a high risk for spreading Middle East respiratory syndrome coronavirus (MERS-CoV). To prevent outbreaks, active surveillance is necessary. We found that a high percentage of dromedaries in Tunisia are MERS-CoV seropositive (80.4%) or actively infected (19.8%), indicating extensive MERS-CoV circulation in Northern Africa.  相似文献   
8.

Methods

The possible association of brain tumour with headache was investigated in 100 patients seen for brain surgery. Preoperatively, 43 patients suffered from headache. These patients were thoroughly questioned about the nature of their pain. Investigation included the McGill Pain Questionnaire.

Results

In only 11 of the patients was headache the primary symptom of a brain tumour. Pain intensity was found to be lower in patients with brain tumour then in those with extracranial tumours or headache of other origins. Female subjects, patients under 50 years of age and those with elevated intracranial pressure experienced more intensive pain. Diurnal variation in pain intensity was observed in 60% of patients with headache. There was no evidence, however, of an association with elevated intracranial pressure.

Conclusions

Our investigations yielded new information concerning the epidemology of headache accompanying brain tumours. Headache is not an early cardinal symptom of brain tumours, as was generally believed earlier. With the help of the McGill Pain Questionnaire a fine quantitative and qualitative characterization of headache of different origins could be made. The connection between tumour localization and pain lateralization, as well as the possible mechanisms of intracranial pain projection was extensively analysed. The interpretations of the results are at best hypotheses and they do not help determine why more than half of the patients with brain tumour did not experience headache.  相似文献   
9.
OBJECTIVES: Many establishments serve alcoholic beverages to obviously intoxicated patrons despite laws against such sales. To guide the development of interventions to reduce these illegal alcohol sales, this study used actors feigning intoxication to determine whether servers recognized obvious signs of intoxication and to assess the tactics servers used when dealing with intoxicated patrons. METHODS: Male actors ages 30 to 50 acted out signs of obvious intoxication as they attempted to purchase alcoholic beverages. If served during the first attempt, these pseudo-intoxicated buyers made second purchase attempts during the same visit. Observers accompanied the actors; after each visit, actors and observers recorded the servers' behavior and comments. RESULTS: Alcoholic beverages were served to actors portraying intoxicated patrons at 68% of first purchase attempts and 53% of second purchase attempts (62% of a total of 106 purchase attempts). The most common refusal technique was a direct refusal (68% of refusals), made with either no excuse or with reference to the actors' apparent intoxication level. Servers' second most commonly used refusal technique was offering alcohol-free beverages, such as coffee or water (18% of refusals). CONCLUSIONS: Further research is needed to determine why servers who recognize intoxication serve alcoholic beverages and what training, outlet policies, and external pressures are needed to reduce illegal alcohol sales to obviously intoxicated patrons.  相似文献   
10.
Antigen expression was studied by immunohistochemistry in 133 human melanocytic skin lesions to gain insight into the initial steps of tumor development, i.e. in particular the change from melanocytes to benign nevi. We refer to the proposed progression model of Clark and co-workers. The following types of antigens were investigated: (i) intermediate filament antigens (vimentin), (ii) melanoma-associated antigens (HMB-45, NKI/C3, MA-930, LS59), (iii) proliferation-associated antigens (S-100, Ki67, Ro/SSA, calmodulin), (iv) progression-associated antigens (HLA-DR, ICAM-1), and (v) basal membrane antigens (bullous pemphigoid antigen, laminin, fibronectin, collagen type IV). The intensity of expression and the topography of immunoreactive pigment cells were compared with the stage of tumor progression. Special attention was paid to the early steps of this process, i.e. the disturbance of the epidermal melanin unit and the development of melanocytic ("nevocellular")nevi. A dramatic shift of antigen expression (antigen types [i] to [v]) was noted in benign nevi compared with melanocytes. Nevi with cellular atypia disclosed a tendency towards an increased percentage of tumor cells reactive for melanoma- and progression-related antigens (types [ii] and [iv]). However, there was no clear cut level of distinction of antigen expression (types [i] to [v]) between benign and primary malignant melanocytic tumors. So-called dysplastic nevi resembled benign tumors or melanocytes rather than malignant melanoma. Metastatic melanoma of skin showed a relatively high number of Ki67-positive, cycling melanoma cells. The results have a bearing on the concepts of melanocytic nevus ontogenesis and "maturation". It appears that melanocytes lose maturity on their way down to the dermis in contrast to traditional concepts (Abtropfung); this might be of importance for our understanding of melanoma development in association with melanocytic nevi. Our findings are discussed with regard to Clark's model of tumor progression.  相似文献   
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