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91.
Hodgkin's disease in patients with previous infectious mononucleosis.   总被引:2,自引:0,他引:2  
Patients with a positive reaction to the Paul-Bunnell test in the period 1961-72 were identified at nine different laboratories in Norway and matched against cases of malignant lymphoma registered at the Cancer Registry of Norway in the period 1961-75. Among 5,840 patients having a positive Paul-Bunnell test a total of six developed malignant lymphoma, three of these more than 1 year after the positive Paul-Bunnell test. The expected number of malignant lymphoma was 2.04. Of the six lymphoma cases, five were classified as Hodgkin's disease (HD). The present investigation agrees well with the findings of other epidemiological studies. There seems to be a small excess in incidence of HD among patients with previous infectious mononucleosis (IM), but both diagnostic problems and possible confounding factors must be taken into account before a possible causal association is considered.  相似文献   
92.
Here we describe the identification of a novel vertebrate-specific centrosome/spindle pole-associated protein (CSPP) involved in cell-cycle regulation. The protein is predicted to have a tripartite domain structure, where the N- and C-terminal domains are linked through a coiled-coil mid-domain. Experimental analysis of the identified domains revealed that spindle association is dependent on the N-terminal and the coiled-coil mid domain. The expression of CSPP at the mRNA level was detected in all tested cell lines and in testis tissue. Ectopic expression of CSPP in HEK293T cells blocked cell-cycle progression in early G1 phase and in mitosis in a dose-dependent manner. Interestingly, mitosis-arrested cells contained aberrant spindles and showed impairment of chromosome congression. Inhibition of CSPP gene expression by small interfering RNAs induced cell-cycle arrest/delay in S phase. This phenotype was characterized by elevated levels of cyclin A, decreased levels of cyclin E and hyperphosphorylation of the S-phase checkpoint kinase Chk1. The activation of Chk1 may indicate a replication stress response due to an inappropriate G1/S-phase transition. Taken together, we demonstrate that CSPP is associated with centrosomes and microtubules and may play a role in the regulation of G(1)/S-phase progression and spindle assembly.  相似文献   
93.
94.
OBJECTIVE: Accurate and reproducible assessment of myocardial infarction is important for treatment planning in patients with ischemic heart disease. This study describes a novel method to quantify myocardial infarction by semi-automatic delineation of hyperenhanced myocardium in delayed contrast enhanced (DE) magnetic resonance (MR) images. DESIGN: The proposed method automatically detects the hyperenhanced tissue by first determining the signal intensity of non-enhanced myocardium. A fast level set algorithm was used to limit the heterogeneity of the hyperenhanced regions, and to exclude small regions that constitute noise rather than infarction. The method was evaluated in 40 patients; 20 with acute infarction and 20 with chronic healed infarction using scanners from two different manufacturers. Infarct size measured by the proposed semi-automatic method was compared with manual measurements from three experienced observers. The software used is freely available for research purposes at http://segment.heiberg.se. RESULTS: The difference in infarct size between semi-automatic quantification and the mean of the three observers was 6.1+/-6.6 ml (mean+/-SD), and the interobserver variability (SD) was 4.2 ml. CONCLUSIONS: The method presented is a highly automated method for analyzing myocardial viability from DE-MR images. The bias of the method is acceptable and the variability is in the same order of magnitude as the interobserver variability for manual delineations.  相似文献   
95.
We conducted a study among healthcare workers (HCWs) exposed to patients with severe acute respiratory syndrome (SARS) before infection control measures were instituted. Of all exposed HCWs, 7.5% had asymptomatic SARS-positive cases. Asymptomatic SARS was associated with lower SARS antibody titers and higher use of masks when compared to pneumonic SARS.  相似文献   
96.
INTRODUCTION: Annually more than 2 million pilgrims from all over the world attend the Hajj in Saudi Arabia. Overcrowding during this pilgrimage leads to a high risk of transmission of airborne infectious diseases. Tuberculosis (TB) is common among hospitalized pilgrims, but the overall risk of acquiring Mycobacterium tuberculosis infection during this pilgrimage is not known. We conducted a prospective study to assess the risk of M. tuberculosis infection among Hajj pilgrims. METHODS: We measured the immune response to TB antigens using a whole-blood assay (QuantiFERON TB assay) prior to departure and 3 months after return from the Hajj pilgrimage. RESULTS: Of 357 paired assays, 149 pilgrims were negative prior to the Hajj and 15 (10%) of these had a significant rise in immune response to TB antigens. CONCLUSIONS: Pilgrims may be at high risk of acquiring M. tuberculosis infection during the Hajj. This has significant public health implications for TB control in countries with large Muslim populations.  相似文献   
97.
A gastrostomy device is removed from the gastrostoma when no longer needed. The aim of the study was to test the hypothesis of whether it is possible for the surgeon to decide which stoma has to be closed with a gastroraphy and which to leave for a spontaneous closure within a reasonable period of time. Out of a cohort of 321 patients, who had been operated with a video-assisted gastrostomy, we included all the 48 patients having had their gastrostomy button removed. These patients were carefully followed and the closure of the gastrostoma was registered. According to the institutional routine we waited at least 3 months after the removal of the gastrostomy device before suggesting to the child’s guardians an operative closure of the stoma. In 26 patients the stoma closed within 3 months, whereas in 22 patients a surgical gastroraphy was performed. We found no differences between the two groups regarding the patients’ diagnoses, the duration of the gastrostoma use or patient’s age at the time of removal of the gastrostomy device. This study rejected the hypothesis of predictability of the gastrostoma closure. Thus, we recommend a routine expectance after the removal of a gastrostomy device for at least 1 month. If no spontaneous closure occurs, then a gastroraphy should be performed.  相似文献   
98.
The aim of this study was to find predictors of neuropathy and reactions, determine the most sensitive methods for detecting peripheral neuropathy, study the pathogenesis of neuropathy and reactions and create a bank of specimen, backed up by detailed clinical documentation. A multi-centre cohort study of 303 multibacillary leprosy patients in Northern India was followed for 2 years. All newly registered MB patients requiring a full course of MDT, who were smear positive and/or had six or more skin lesions and/or had two or more nerve trunks involved, were eligible. A detailed history was taken and physical and neurological examinations were performed. Nerve function was assessed at each visit with nerve conduction testing, warm and cold detection thresholds, vibrometry, dynamometry, monofilaments and voluntary muscle testing. Because the latter two are widely used in leprosy clinics, they were used as 'gold standard' for sensory and motor impairment. Other outcome events were type 1 and 2 reactions and neuritis. All subjects had a skin biopsy at registration, repeated at the time of an outcome event, along with a nerve biopsy. These were examined using a variety of immunohistological techniques. Blood sampling for serological testing was done at every 4-weekly clinic visit. At diagnosis, 115 patients had an outcome event of recent onset. Many people had skin lesions overlying a major nerve trunk, which were shown to be significantly associated with an increased of sensory or motor impairment. The most important adjusted odds ratios for motor impairment were, facial 4.5 (1.3-16) and ulnar 3.5 (1.0-8.5); for sensory impairment they were, ulnar 2.9 (1.3-6.5), median 3.6 (1.1-12) and posterior tibial 4.0 (1.8-8.7). Nerve enlargement was found in 94% of patients, while only 24% and 3% had paraesthesia and nerve tenderness on palpation, respectively. These increased the risk of reactions only marginally. Seven subjects had abnormal tendon reflexes and seven abnormal joint position sense. In all but one case, these impairments were accompanied by abnormalities in two or more other nerve function tests and thus seemed to indicate more severe neuropathy. At diagnosis, 38% of a cohort of newly diagnosed MB leprosy patients had recent or new reactions or nerve damage at the time of intake into the study. The main risk factor for neuropathy found in this baseline analysis was the presence of skin lesions overlying nerve trunks. They increased the risk of sensory or motor impairment in the concerned nerve by 3-4 times. For some nerves, reactional signs in the lesions further increased this risk to 6-8 times the risk of those without such lesions. Patients with skin lesions overlying peripheral nerve trunks should be carefully monitored for development of sensory or motor impairment.  相似文献   
99.
The study of quality of life has increased in importance in the area of mental disorders during the last decade. The aim of the present study was to investigate the effect of specific anxiety disorders on specific quality of life indicators in the common population. More than 2000 individuals between 18 and 65 years old were studied by means of structured interviews. The results showed that social phobia and panic disorder within the past year and lifetime, and generalized anxiety disorder within the past year, had an independent effect on quality of life when controlling for a number of sociodemographic variables, somatic health, and other DSM-III-R Axis I mental disorders. Specific phobias and obsessive compulsive disorder had only a small effect, and agoraphobia showed no effect. The effect was strongest for self-realization and contact with friends, but anxiety disorders also influenced subjective well-being, social support, negative life events, contact with family of origin, and neighborhood quality.  相似文献   
100.
PURPOSE: This study examined the possible association of three dental factors with total mortality and death from coronary heart disease. MATERIALS AND METHODS: Samples from two studies were combined, for a total of 2,613 individuals aged 25 to 79 years; a total of 353 deaths occurred, of which 82 were from coronary heart disease. The hazard ratio was calculated for total and coronary heart disease mortality by regression for the dental components; conventional risk factors were controlled for in a stepwise manner. RESULTS: For total and coronary heart disease mortality, associations with both edentulousness and number of years of edentulism were statistically significant until smoking was added into the analysis; then, all significance was lost. When the effect of the oral parameters was studied in relation to total and coronary heart disease mortality, after adjusting for age and gender, there was a significant hazard ratio for total mortality, but only for edentulousness. When examined by stepwise regression of the coronary heart disease risk factors, all significance of risk from the three oral parameters was lost, smoking having the largest effect of all risk factors. CONCLUSION: Number of remaining teeth, edentulousness, and number of years of edentulism were not independent risk factors for total or coronary heart disease mortality, but they were surrogate markers for the risk from smoking.  相似文献   
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