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101.
102.
By means of electron microscopy a study has been made on Sarcocystis from 29 camels (Camelus dromedarius) in Egypt. In oesophagus and diaphragm muscles sarcocysts have been observed. The micromorphology of metrocytes, merozoites as well as of the cyst wall has been described.  相似文献   
103.
A case of CSF fistula, formed as a result of old fracture of the anterior cranial fossa, presented with recurrent meningitis and CSF rhinorrhea due to herniation of markedly dilated right frontal horn of lateral ventricle into the right ethmoid sinus through fractures of right frontal bone, cribriform plate of ethmoid and roof of orbit is reported. Attention was drawn to the CSF fistula only after recurrent meningitis and detailed imaging studies. Using a right frontal craniotomy approach, successful repair of the CSF fistula was performed and patient was discharged symptom-free.  相似文献   
104.
Transient first-degree heart block developed following surgery to divide a vascular ring. This unusual complication was related to autonomic impairment secondary to a local nerve block. The role of the autonomic innervation of the atrioventricular node and the potential role of the local anesthetic are reviewed.  相似文献   
105.
Whole-blood assays (WB) provide a simple tool for assessing immune cytokine profiles which may be useful laboratory predictors of early disease, aiding the evaluation of new tuberculosis (TB) vaccines and offering insights into disease pathogenesis. Although BCG does not provide protection against pulmonary disease in TB endemic areas, it does modulate immune responses to mycobacterial antigens. It is important, therefore, to evaluate any new tool in an endemic setting in both BCG vaccinees and patients with tuberculosis. We have assessed the optimal conditions in terms of dose and kinetics of those cytokines which are released early (TNF-alpha, IL6 and TGF-beta, IL10) or (interferon [IFN]-gamma and IL5) in WB cultures stimulated with mitogens and mycobacterial antigens. Responses were studied in parallel in untreated TB patients and endemic control groups. Optimal responses to LPS (predominantly monocyte-derived) occurred on days 1-2, whereas for PHA (predominantly T-cell-derived), they were on days 3-5. Secreted Mycobacterium tuberculosis culture filtrate proteins (CFP) provided a stronger stimulus for monocyte-derived cytokines compared to PPD, but both antigens were comparable for induction of T-cell cytokines. Using unpaired Student's t-tests, pulmonary tuberculosis patients (P.TB; n=11), in response to CFP, showed higher monocyte-derived IL6 (p=0.023) and IL10 (p=0.042) compared to endemic controls (EC; n=13), and significantly suppressed T-cell-derived IFN-gamma (p=0.028) and IL5 (p=0.012) secretion but increased IL10 (p=0.047) on day 5, indicating that CFP is a strong stimulus for IL10 secretion in pulmonary TB patients. Extrapulmonary TB patients (E.TB; n=6) showed no elevation of early monocyte-derived cytokines to either PPD or CFP, but showed a marked suppression of the T-cell-derived cytokines IFN-gamma (PPD, p=0.015; CFP, p=0.05) and IL5 (PPD, p=0.05; CFP, p=0.015). Cytokine analysis in WB cultures is, therefore, able to discriminate between active tuberculosis infection and nondiseased healthy controls.  相似文献   
106.
Injuries are an important public health problem and a leading cause of death among adults and children. In most of the developing world, with rapid changes in lifestyle, rural development, urbanization, an increase in number of vehicles, introduction of mechanized farming and pesticides in agriculture, the effect of injuries on mortality and morbidity is expected to increase. Injuries have been infrequently studied in developing countries; their importance is incompletely understood and they are seriously neglected in health research and policy. The reasons for this situation may be many, but one important reason is the unavailability of data in countries to assess the magnitude of the problem. Hospital and police records are the primary data source for injuries in the majority of the developing world. Newspaper reports may be an alternative source for injury data. This hypothesis was tested in the Rawalpindi Division of Pakistan by collecting data from newspaper reports for both intentional and unintentional injuries for 6 months (January-June 1999). This was compared with police data for the same time period. The results revealed that newspapers report more injury-related events and for some categories, such as suicides, the reporting was far greater by newspapers than the police. We conclude that the current system of police data collection needs to be strengthened. Newspapers may serve as a comparative source of information to evaluate the coverage of police data.  相似文献   
107.
BACKGROUND: In the preantibiotic era acute mastoiditis was the most common complication of acute otitis media, often resulting in substantial morbidity and mortality. Since 1989 several investigators have documented an increased frequency of acute mastoiditis in children. METHODS: The medical records of all children with a discharge diagnosis of acute mastoiditis, managed at Children's Medical Center, Dallas, TX, from 1983 through 1999 were reviewed. RESULTS: There were 57 cases of acute mastoiditis during the 17-year period of 1983 through 1999 compared with 57 cases in a 25-year period of 1955 through 1979 reported previously at the same institution. The number of cases of acute mastoiditis per 10,000 hospital admissions increased significantly (regression analysis P = 0.003) during the more recent 17 years. From 1993 through 1999 there were 4.5 cases or more per 10,000 admissions each year, whereas from 1983 through 1992, the incidence never exceeded 4.3 cases per 10,000 admissions (P = 0.018). The median age of the patients was 48 months. Twenty-two patients (38.5%) were younger than 24 months; 17 of these were 12 months of age or younger. Twenty-two (38.5%) patients had no history of previous episodes of acute otitis media. Streptococcus pneumoniae was the pathogen most often isolated from the cultures. Complications of mastoiditis occurred in 20 children (35%). CONCLUSIONS: We conclude that acute mastoiditis continues to be a problem in the post antibiotic era. It occurs mainly in young children and can be the first evidence of ear disease.  相似文献   
108.
109.
Prefrontal cortex and episodic memory retrieval mode   总被引:1,自引:0,他引:1       下载免费PDF全文
A multistudy analysis of positron emission tomography data identified three right prefrontal and two left prefrontal cortical sites, as well as a region in the anterior cingulate gyrus, where neuronal activity is correlated with the maintenance of episodic memory retrieval mode (REMO), a basic and necessary condition of remembering past experiences. The right prefrontal sites were near the frontal pole [Brodmann's area (BA) 10], frontal operculum (BA 47/45), and lateral dorsal area (BA 8/9). The two left prefrontal sites were homotopical with the right frontal pole and opercular sites. The same kinds of REMO sites were not observed in any other cerebral region. Many previous functional neuroimaging studies of episodic memory retrieval have reported activations near the frontal REMO sites identified here, although their function has not been clear. Many of these, too, probably have signaled their involvement in REMO. We propose that REMO activations largely if not entirely account for the frontal hemispheric asymmetry of retrieval as described by the original hemispheric encoding retrieval asymmetry model.  相似文献   
110.
The skin prick test (SPT) could be applied as a useful in vivo method for the detection of sensitization in epidemiological and diagnostic studies if the wheal size is ideally evaluated. We focused on SPT wheal size to identify sensitization pattern to common inhalant and food allergens. In this cross‐sectional study, SPT results were obtained from a total of 972 allergic patients. Common allergen extracts for SPT were selected according to the type of allergic diseases, and the geographical pattern. SPT with food allergens was performed for patients with atopic dermatitis (AD) and chronic urticaria (CU). A total of 461 male (47.4%) and 511 female (52.6%) participated in this study (median age: 31 years). The majority of individuals were affected with allergic rhinitis (AR) (n = 624) and asthma (n = 224); while 129 and 67 patients suffered from AD and CU, respectively. The most common aeroallergens were Russian thistle (52.1%) and lamb's quarter (50.7%) with the largest wheal diameter. The wheal size of lamb's quarter was significantly different between patients with asthma and AR (P<.001). In addition, a significant difference was detected in wheal diameter in response to the Russian thistle between patients with AR and AD (P = .001). Shrimp (23.6%) and Peanut (22.5%) caused the most common food sensitization in patients with AD and CU. Having in mind the most common weed pollens including the Russian thistle and lamb's quarter, preventive strategies, such as, removing unwanted weeds or preventing them from growing, avoidance, and specific immunotherapy may be crucial for better disease control.  相似文献   
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