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1.
OBJECTIVE: Rheumatoid arthritis (RA) may be biologically reversible if treated in the first several months, yet it is unknown whether patients are diagnosed that early. We investigated the lag time between symptom onset and diagnosis of RA in a population with excellent access to rheumatology care. METHODS: Using review of medical records, we evaluated all patients newly diagnosed as having RA from 1987 through 1990, at a health maintenance organization in central Massachusetts. Total lag time from symptom onset to first definite diagnosis was divided into medical encounter lag time (from symptom onset to first medical encounter) and diagnosis lag time (from first medical encounter to diagnosis). RESULTS: The median total lag time was 36 weeks (range 4 weeks to > 10 years). The median medical encounter lag time was 4 weeks (not all patients included in the analysis). The median diagnosis lag time was 18 weeks. Diagnosis lag time was shorter for patients with progressive disease and positive rheumatoid factor on the initial test. Of 25 patients with symmetric arthritis and positive rheumatoid factor, only 5 (20%) were diagnosed within 2 months, and 10 (40%) were diagnosed more than 6 months after symptom onset. CONCLUSION: RA diagnosis is usually delayed for several months after symptoms begin, in large part because of delay in diagnosis by the physician. Thus, the goal of initiating treatment extremely early may be unrealistic for most patients.  相似文献   

2.
In studies of elderly individuals, ventilation and EEG-defined arousal have been shown to vary periodically and synchronously. Such results have been interpreted as indicating the primacy of sleep/wake state in causing ventilatory instability during sleep onset. However, because the elderly individuals studied were periodic breathers, the results do not unequivocally support this conclusion. In this study the relationship between ventilation and EEG-defined arousal was assessed in a group of 21 young, healthy men in whom ventilatory instability during sleep onset was not periodic. Ventilation and EEG (O1-A2) recordings were collected, and the longest uncontaminated periods from early and late in sleep onset were selected for subsequent analysis. The 84 time series (21 subjects, 2 variables, and 2 occasions in sleep onset) were subjected to spectral analysis to identify periodicity, and the relationship between the two variables was determined by cross-correlational methods. The results indicated that the time series were nonperiodic, yet significant correlations were observed between the two variables. The data support the view that during sleep onset ventilatory instability is driven primarily by variations in sleep/wake arousal level.  相似文献   

3.
The efficacy of vitamin A in the prevention of oral cavity cancer has been studied during the last years due to the interest for a possible application of new drugs in the treatment of second primary tumours and multiple neoplasms. Fifty patients with oral precancerous lesions treated at the "Centre for prevention of oral cavity cancer" of the "Regina Elena" Institute in Rome, have been subjected to a rigorous questionnaire about their use of vitamin A in the diet. Moreover a standard sample of fifty healthy people without oral cavity lesions.  相似文献   

4.
Huntington's disease (HD) is an autosomal dominant disorder with a variable age of onset that is influenced by the sex of the affected parent. The recent recognition that HD is caused by an expanded triplet repeat suggests the possibility that the onset age may be predicted by the length of the repeat. This hypothesis was tested by assaying the length of the repeat in 114 individuals who were clinically diagnosed with HD and had a known onset age. Every individual had an expanded allele. The range was from 36 to 82 repeats (mean = 48.4 +/- 9.51) and larger than the normal range (6 to 31). The size of the expanded allele was correlated with the age of onset (r = -0.65 p < .0001). Despite the highly significant correlation, the repeat size explains less than half of the variance in onset age. Furthermore, the age of onset cannot be predicted from the size of the triplet repeat, particularly if the number of repeats is in the smaller end of the expanded range. If the repeat is < or = 50 triplets, the amount of variation in the age of onset explained by the length of the triplet repeat is less than 10%. As an illustration, the onset age of individuals with 39 repeats ranges from 30 to 65 years old. The sex of the affected parent had no effect in our sample beyond the effect of the length of the repeat. Affected offspring of affected fathers had longer repeats and a larger variance in allele size than offspring of affected mothers, perhaps reflecting greater instability in paternal transmission.  相似文献   

5.
钨矿区砷污染与土壤微生物及酶活性相关性研究   总被引:2,自引:0,他引:2       下载免费PDF全文
通过野外采样及室内分析,研究赣南钨矿区的砷污染状况,土壤砷含量和形态对土壤微生物群落以及土壤酶活性的影响.结果表明:钨矿区土壤中砷全量及有效量均显著高于非矿区土壤,矿区土壤中砷以铁锰氧化物结合态为主,生物可给性强的可交换态砷占9.8 %~12 %,尾矿砂中砷以残渣态为主(39.7 %),交换态砷占16.6 %.矿区土壤砷总量、可利用态砷对矿区土壤微生物数量的影响也呈现负相关,微生物类群对矿区污染的敏感性大小表现为:细菌>放线菌>真菌.矿区土壤脲酶、过氧化氢酶、蔗糖酶活性均受到砷污染的抑制,通过相关性分析得出,脲酶活性可以较好的指示钨矿区土壤砷污染程度.钨矿区土壤中微生物区系组成数量及土壤酶活性在一定程度上可反映该矿区砷污染特征.   相似文献   

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INTRODUCTION: During the last 20 years routine application of various methods of multiple "small biopsies" of the lungs such as forceps, transbronchial, trucut percutaneous and so on, has significantly increased the efficacy of diagnostics of bronchopulmonary and pleural diseases. Tissue samples, not bigger than 3-4 mm, in which diagnostic pathological changes are expected on the basis of previous clinical, radiological and bronchoscopic examinations, can be the basis for making a definite therapeutical decision only if a skillful surgeon has performed the biopsy by correct instruments and from the right place and sent it for histological analysis with other important clinical information. This study is a comment on quality, significance and possibilities of improving clinical-pathological cooperation in this field of clinical pathology. MATERIAL AND METHODS: By correlation of clinical and histological diagnoses we analyzed the diagnostic efficiency of microscopic examinations of "small biopsies" of the respiratory tract in 319 patients (175 bronchial forceps biopsies, 31 transbronchial biopsies, 22 percutaneous needle pleural biopsies and 91 combined forceps and transbronchial biopsies) in whom biopsies were performed during 1996 in the Specialized Hospital for Lung Diseases Brezovik. RESULTS: Overall concordance between the clinical and histopathological diagnosis was 82.2%. In 99 cases (73.3%) out of 135 clinically "obvious" neoplasms, the histopathological examination confirmed existence of malignant tumor: squamous cell carcinoma in 80%, small cell carcinoma in 9.6% and adenocarcinoma in 5.6% of patients. In other patients it was not possible to perform a more precise classification. Endoscopic specimens of 29 patients (9.1%) were not representative. CONCLUSION: The level of diagnostic efficiency (73.3%) of definitive histopathological verification of bronchopulmonary lesions, which have been clinically diagnosed as malignancies, is rather high, but the increase of diagnostic efficiency requires application of more sophisticated histological diagnostic methods (immunohistochemical) and more frequent utilization of bioptic procedures which are more convenient for detection of peripheral pulmonary lesions (transbronchial and percutaneous fine needle aspiration biopsies of the lungs).  相似文献   

8.
Congenital tracheoesophageal fistula without atresia can persist and remain undetected without symptoms until adulthood. We have recently encountered such a rare case and also conducted a review of the literature. Symptoms are commonly present during infancy, but occasionally patients do not develop symptoms until adulthood. In this case, it is suggested that the symptoms commenced after the redundant mucosal flap or membrane was broken due to a trauma to the chest.  相似文献   

9.
The aim of this study was to define the accuracy of 99mTc-ethyl cysteinate dimer-single photon emission computed tomography (99mTc-ECD-SPECT) in distinguishing transient ischemic attack from completed ischemic stroke at early stages after the onset of symptoms. In a prospective study we examined 82 patients within 6 hours after the onset of symptoms (neurologic deficit caused by middle cerebral artery ischemia) using both 99mTc-ECD-SPECT and computed tomography (CT). The follow-up was based on Scandinavian Stroke Scale (SSS) 24 hours and 5-7 days, as well as on CT 7 days, after the event. SPECT evaluation was performed both visually and using semiquantitative region-of-interest (ROI) analysis. According to visual SPECT analysis, on admission 59 of 82 patients had activity deficits in the symptomatic hemisphere. After 7 days, all these patients had neurologic symptoms (SSS 28 +/- 12 points), caused by a cerebral infarction as evidenced with CT. Twenty-three of 82 patients displayed no early activity deficit despite clinical symptoms. None of these patients had neurologic symptoms after 7 days (indicating transient ischemic attack or prolonged reversible ischemic neurologic deficit). In the semiquantitative SPECT analysis, all patients had abnormal count densities in the respective ROI (activity < 90% compared with the contralateral side). All patients with transient ischemia (n = 23) had count rate densities more than 70% of the respective contralateral ROI, whereas all patients with subsequent infarction (n = 59) had values < 70%. Use of 99mTc-ECD-SPECT allows transient ischemia to be distinguished from ischemic infarction using relative regional activity thresholds within the first 6 hours after onset of symptoms.  相似文献   

10.
In eliminating contamination at the surface of cold-rolled strip, it is important to ensure the required characteristics of the rolling emulsion. Accordingly, the emulsion parameters determining the purity of the metal surface beyond the 1700 five-cell cold-rolling mill are investigated in casting and rolling shop 2 at AO ArcelorMittal Temirtau.  相似文献   

11.
Examined the additive and interactive roles of 6 sociodemographic factors (education, age, sex, marital status, parental depression, and early parental death), 3 resources (health, social support, and locus of control), and 3 categories of life events (bereavement, health problem, and loss events) in the development of depressive symptoms. A probability sample of 1,233 persons (aged 55+ yrs) were interviewed twice in their homes, with a 6-mo interval between Times 1 and 2. All Ss were below a Center for Epidemiologic Studies Depression Scale (CES-D) cutoff point of 16 at Time 1. An onset group (n?=?66) was identified that had increases in depression to above a CES-D cut point of 20 at Time 2. A hierarchical discriminant analysis revealed significant effects for the following factors after initial symptom levels were statistically controlled: physical health, social support, social support and health interaction, loss events, and the interaction of social support and loss events. It is concluded that health and social support played both additive and interactive roles, life events had weak effects, and sociodemographic factors did not contribute to depressive onset in the Ss studied. (85 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
DNA hybridization with oligonucleotide probes is a powerful technique to study population genetics and structures. The use of probes which recognize ubiquitously interspersed DNA sequences has a distinct advantage over other techniques (e.g. the analysis of patterns of restriction fragment length polymorphism) in that many independent loci can be detected simultaneously. In this communication, we investigated the use of a trinucleotide repetitive DNA oligonucleotide, poly(GTG)5, in Southern blot analysis of Salmonella serotypes and Shigella species. The strains in this study were isolated over several years from widely disparate geographic locations and can therefore be considered to represent the structure of part of the natural populations of these organisms. In most of the Salmonella serotypes, the poly(GTG)5-associated profile (GTG profile) phenotypes appeared to be clonally stable; in cases where only one isolate of a serotype was tested, the GTG profile was distinct from the others. On the other hand, when GTG profile analysis was applied to Shigella strains, each of the 12 isolates, belonging to the four Shigella species, produced a unique pattern phenotype of both the chromosome and plasmid DNA.  相似文献   

13.
BACKGROUND: The Canadian Coronary Atherectomy Trial (CCAT) assessed, in a randomized comparison, the clinical and angiographic outcomes following atherectomy with those following balloon angioplasty for the treatment of de novo lesions in the proximal one-third of the left anterior descending artery (LAD). Although the procedural success rate was somewhat higher and the postprocedure lumen larger in patients treated with atherectomy, lumen dimensions, restenosis rates and clinical outcomes were similar in the two groups at six months. To determine whether late differences emerged between the groups, clinical follow-up was obtained at a median of 18 (range 10 to 31) months after randomization. METHODS AND RESULTS: Patients were contacted monthly by telephone for the first six months. Subsequent follow-up information was obtained in 272 (99%) of the 274 randomized patients via a clinic visit or telephone interview with the patient and/or a relative. Additional information was obtained from the referring physician as required. There were no differences in adverse events between the two groups during follow-up. In patients randomized to atherectomy compared with balloon angioplasty, death occurred in 1.5% versus 2.2% (cardiac death 0.7% versus 0.7%); myocardial infarction in 5.1% versus 5.9% (Q wave 1.5% versus 1.5%); coronary bypass surgery in 13.1% versus 12.6%; and repeat target lesion intervention in 22.6% versus 21.5%. Persistent or recurrent Canadian Cardiovascular Society class III/IV angina not treated by a further intervention was present in 1.5% versus 2.2%. The combined end-point of death or nonfatal myocardial infarction occurred in nine (6.6%) versus 11 (8.1%) patients and any adverse cardiac event in 50 (36.5%) versus 53 (39.3%). Multivariate logistic regression indicated that unstable angina, reference vessel size and preprocedure minimum lumen diameter were the only variables independently associated with adverse events. CONCLUSIONS: The initial choice of directional atherectomy or balloon angioplasty had no impact on clinical outcome over a period of 18 months in this patient population. With either technique, just over 60% of patients with proximal LAD disease experienced sustained symptomatic improvement without an adverse event following a single procedure, and 80% achieved this status following a repeat percutaneous intervention.  相似文献   

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OBJECTIVE: To determine the correlation between water content and magnetization transfer (MT) ratio of the water component in normal bone marrow using gradient-echo (GRE) magnetic resonance (MR) imaging. DESIGN: Three types of GRE sequence--using fat suppression, using a combination of MT and fat suppression techniques, and without MT or fat suppression--were performed in nine healthy subjects. The water content of bone marrow assessed with GRE imaging was compared with that assessed with MR spectroscopy in three cases. The correlation between water content and MT ratio was observed using GRE imaging in nine subjects. RESULTS AND CONCLUSIONS: The water content as assessed by GRE imaging and by MR spectroscopy were closely correlated (P<0.005, r=0.932). An inverse correlation between water content and MT ratio was observed in normal bone marrow (P<0.03, r=-0.432), which suggests that the water component in bone marrow includes free water protons.  相似文献   

16.
A multicompartmental model is developed to simulate the biokinetics in the human body following the ingestion of an inert gas. It was assumed that 100% of the radon ingested appears in the stomach, from which it is transported through the body to different organs via the blood stream. Each of these organs absorbs and releases radon differently, and, amongst all, the fat retains radon for the longest time. To test the model, the information on elimination rates of 222Rn in expired breath was obtained from other experiments done at the University of Maine. The data included male and female participants with a wide range of ages and physical activity levels. The radiation doses in the different organs and tissues were computed. As was expected, the stomach sustained the maximum dose. In this study, the highest stomach dose to any volunteer was evaluated as 115 mSv y(-1).  相似文献   

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18.
This paper reports an assessment of various methods for sampling particulate surface contamination for use in the field. The results from the study will be used to develop guidance for monitoring particulate surface contamination in the workplace. Three types of adhesive tape, two manual and two 'semi-automatic' wipe methods, and one Smair method were assessed. A field assessment of selected methods was carried out in two stages. In stage one, the manual wipes, semi-automatic wipes and adhesive tape (Scotch Tape) were compared. In stage two, the adhesive tape (Scotch Tape), black forensic tape, clear forensic tape and Smair were compared. Visits were made to ten metal processing facilities and particulate contamination was sampled from six locations at each site. Sampling locations were chosen for their potential as points of worker dermal contact and also to represent a range of surface characteristics. The metal content of the samples were analysed using Atomic Absorption Spectrophotometry (AAS) and X-ray Fluorescence Spectrometry (XRF). It was found that the Smair method proved to be inefficient in removing surface contamination, particularly where the surface was damp or greasy. Tape methods were found to be the most satisfactory and have considerably greater efficiency than wipe sampling. The black forensic tape is the preferred sampling medium as it is highly efficient, reproducible and easy to use.  相似文献   

19.
In this era of interventional electrophysiology, the accuracy of the electrocardiogram in diagnosis of supraventricular tachycardia could be improved by detailed endocardial mapping and confirmed by results of radiofrequency catheter ablation. This article describes the electrocardiographic characteristics for different types of supraventricular tachycardia: atrial fibrillation, atrial flutter, atrial tachycardia, atrioventricular reciprocating tachycardia using an accessory pathway, and atrioventricular node reentrant tachycardia. Several limitations, including the identification of P wave morphologies and polarities and separation between the terminal part of T wave and P wave during tachycardia, should be resolved before an accurate algorithm of the 12-lead surface electrocardiogram is developed for the diagnosis of supraventricular tachycardia.  相似文献   

20.
Fluorescence spectral features of 6-propionyl-2-dimethylaminonaphthalene (Prodan) in phospholipid vesicles of different phase states are investigated. Like the spectra of 6-lauroyl-2-dimethylaminonaphthalene (Laurdan), the steady-state excitation and emission spectra of Prodan are sensitive to the polarity of the environment, showing a relevant shift due to the dipolar relaxation phenomenon. Because of the different lengths of their acyl residues, the partitioning of the two probes between water and the membrane bilayer differs profoundly. To account for the contribution of Prodan fluorescence arising from water, we introduce a three-wavelength generalized polarization method that makes it possible to separate the spectral properties of Prodan in the lipid phase and in water, and to determine the probe partitioning between phospholipid and water and between the gel and the liquid-crystalline phases of phospholipids. In contrast to Laurdan, Prodan preferentially partitions in the liquid-crystalline phase with respect to the gel and is sensitive to the polar head pretransition, and its partition coefficient between the membrane and water depends on the phase state, i.e., on the packing of the bilayer. Prodan is sensitive to polarity variations occurring closer to the bilayer surface than those detected by Laurdan.  相似文献   

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