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21.
One hundred eighty-four telephone calls to the Texas State Poison Center concerning accidental hydrocarbon ingestion were reviewed in an attempt to define the risk of developing any subsequent medical problem requiring therapeutic intervention. Special attention was given to changing symptom severity in an attempt to evaluate its usefulness in predicting future complications. One hundred twenty patients (65%) had no initial symptoms and remained asymptomatic throughout an 18-hour follow-up period. Sixty-two (34%) of patients had symptoms initially but quickly became asymptomatic. Two (1%) developed significant complications (one chemical pneumonitis, one death). These data suggest that the risk of significant complications after accidental hydrocarbon ingestion is low (approximately 1% of patients at risk). Patients who are asymptomatic or who quickly become asymptomatic can be watched safely at home, and referral of asymptomatic patients to a hospital may be unwarranted.  相似文献   
22.
Nosocomial pressure ulcers (PU) occur in approximately 12% of all hospitalized patients. The risk can be determined by a variety of intrinsic and extrinsic factors. As a first line of defense against nosocomial PU, we use the Braden Scale to determine the potential risk of PU development during hospitalization. Once risk was identified, our standard was to implement an individualized plan of care. However, consistent implementation of PU preventative measures was lacking. As a result, a process improvement project was developed and implemented. The purpose of this process improvement project was to increase communication about and awareness of the need to vigorously intervene and document whenever there is risk of, or development of, a nosocomial PU. By initiating consistent use of a PU Tracking Form, developing unit-based wound champions that serve as experts in ulcer prevention, and creating an individual case analysis process, PU prevention and tracking was institutionalized. Results indicate that our nosocomial PU rate has declined from 7% to 4%.  相似文献   
23.
Ischemic stroke occurs in 0.2-0.4% of patients undergoing left heart catheterization, and is responsible for 5-10% of the mortality associated with the procedure. The main predisposing factors for this complication are female gender, complex atherosclerotic plaques in the ascending aorta, and peripheral arterial disease. The possibility of timely intervention with reperfusion therapy supports close clinical monitoring during the immediate post-catheterization period. The cardiologist should be familiar with the various types of stroke reperfusion therapy and its indications according to the time interval between catheterization and the stroke. The decision should be discussed with neurology and neuroradiology.  相似文献   
24.
Ninety-four Olmsted County, Minnesota residents with temporal arteritis (TA) initially diagnosed between 1950 and 1985 (incidence cohort) were identified. The age- and sex-adjusted incidence of TA per 100,000 population age 50 years or older was 17.0 (95% confidence interval [CI] 13.6-20.5), with a marked increase in incidence with age and a threefold greater incidence in women (23.4, 95% CI 18.2-28.7) than in men (7.4, 95% CI 3.7-11.0). The previously described secular increase in TA incidence in Olmsted County women continued from 1970 through 1985, while TA incidence in men declined in this latter time period. Although the frequency of classic clinical manifestations of TA declined over time, the percentage of patients undergoing biopsy who have positive specimens remained relatively constant (women 41%, men 26%). The incidence rate of temporal artery biopsy also increased for women during this period, but declined for men, suggesting that the differing trends in TA incidence by sex may be partially attributable to a detection bias. Future research in TA etiology and epidemiology should focus on possible causal factors linked to the differential TA incidence by sex.  相似文献   
25.
In Corte de Pedra (CP), northeastern Brazil, Leishmania braziliensis causes three distinct forms of American tegumentary leishmaniasis (ATL). To test the hypothesis that strain polymorphism may be involved in this disease spectrum and accurately characterize the parasite population structure in CP, we compared one L. major, two non-CP L. braziliensis, one CP L. amazonensis, and 45 CP L. braziliensis isolates, obtained over a 10-year period from localized cutaneous, mucosal, and disseminated leishmaniasis patients, with randomly amplified polymorphic DNA (RAPD). Electrophoretic profiles were mostly unique across species. All typing protocols revealed polymorphism among the 45 CP L. braziliensis isolates, which displayed eight different RAPD patterns and greater than 80% overall fingerprint identity, attesting to the adequacy of the tools to assess strain variability in CP's geographically limited population of parasites. The dendrogram based on the sum of RAPD profiles of each isolate unveiled nine discrete typing units clustered into five clades. Global positioning showed extensive overlap of these clades in CP, precluding geographic sequestration as the mechanism of the observed structuralization. Finally, all forms of ATL presented a statistically significant difference in their frequencies among the clades, suggesting that L. braziliensis genotypes may be accompanied by specific disease manifestation after infection.  相似文献   
26.
Hematopoietic stem cell transplant recipients lose immune memory of exposure to infectious agents and vaccines accumulated through a lifetime, and therefore need to be revaccinated. Reimmunization protocols vary greatly among hematopoietic stem cell transplant centers. Diphtheria and tetanus toxoids, pertussis vaccine, Haemophilus influenza type B conjugate, 23-valent pneumococcal polysaccharide, inactivated influenza and polio vaccine and live attenuated measles-mumps-rubella vaccine are the currently recommended vaccines to be included in a vaccination program after hematopoietic stem cell transplant. Other variables, such as stem cell source, new adjuvants, T-cell depleted transplants, nonmyeloablative conditioning and donor immunization have recently been introduced and a constant update of current recommendations are needed. Studies recently published, the use of other vaccines and the perspectives for different vaccination protocols are discussed in this review.  相似文献   
27.
Most U.S. medical schools offer courses in the behavioral and social sciences (BSS), but their implementation is frequently impeded by problems. First, medical students often fail to perceive the relevance of the BSS for clinical practice. Second, the BSS are vaguely defined and the multiplicity of the topics that they include creates confusion about teaching priorities. Third, there is a lack of qualified teachers, because physicians may have received little or no instruction in the BSS, while behavioral and social scientists lack experience in clinical medicine. The authors propose an approach that may be useful in overcoming these problems and in shaping a BSS curriculum according to the institutional values of various medical schools. This approach originates from insights gathered during their attempts to teach various BSS topics at four Israeli medical schools. They suggest that medical faculties (1) adopt an integrative approach to learning the biomedical, behavioral, and social sciences using Engel's "biopsychosocial model" as a link between the BSS and clinical practice, (2) define a hierarchy of learning objectives and assign the highest priority to acquisition of clinically relevant skills, and (3) develop clinical role models through teacher training programs. This approach emphasizes the clinical relevance of the BSS, defines learning priorities, and promotes cooperation between clinical faculty and behavioral scientists.  相似文献   
28.
The immunological basis for the production of autoantibodies characteristic of systemic lupus erythematosus (SLE) against a wide range of antigens remains obscure. The specificity of (NZB x NZW)F1 (BWF1) or MRL/Mp-lpr/lpr (MRL/lpr) mouse monoclonal antibodies (mAb) was examined by immunofluorescence, immunoblotting and immunoprecipitation techniques. Using non-synchronized HEp-2 cells as substrate, the murine mAb were classified by indirect immunofluorescence into five groups on the basis of their staining patterns of subcellular components in interphase and mitotic stages of the cell cycle. The nature of the antigens recognized by the murine lupus was assessed by immunoblotting experiments in total, cytoplasmic and nuclear cell extracts from HEp-2 cells. The six antibodies used recognized in total cell extracts a range of polypeptides with apparent molecular weights from 25,000 to 210,000. Three polypeptides of 130,000, 110,000 and 45,000 MW were recognized by all six antibodies in both nuclear and cytoplasmic extracts. Immunoprecipitation of total cellular extracts labelled with [35S]methionine showed almost the same pattern as obtained in the immunoblotting assay. The labelling in vivo of HEp-2 cells with [32P], followed by the immunoprecipitation of the [32P]cell lysate showed that these mAb recognized phosphorylated proteins. The progressive decrease in reactivity of these mAb following treatment with higher concentrations of alkaline phosphatase in both [32P]cell lysate or nitrocellulose membranes indicates that these mAb recognize phosphorylated epitopes.  相似文献   
29.
The present experiment aimed at investigating electrophysiologic changes observed as beta band asymmetry, by Quantitative Electroencephalography (qEEG), when individuals performed a reaching motor task (catching a ball in free fall). The sample was composed of 23 healthy individuals, of both sexes, with ages varying between 25 and 40 years old. All the subjects were right handed. A two-way ANOVA was applied for the statistical analysis, to verify the interaction between task moment (i.e., 2 s before and 2 s after ball's fall) and electrode (i.e., frontal, central and temporal regions). The first analysis compared electrodes placed over the somatosensory cortex. Central sites (C3–C4) were compared with temporal regions (T3–T4). The results showed a main effect for moment and position. The second analysis was focused over the premotor cortex, which was represented by the electrodes placed on the frontal sites (F3–F4 versus F7–F8), and a main effect was observed for position. Taken together, these results show a pattern of asymmetry in the somatosensory cortex, associated with a preparatory mechanism when individuals have to catch an object during free fall. With respect to task moment, after the ball's fall, the asymmetry was reduced. Moreover, the difference in asymmetry between the observed regions were related to a supposed specialization of areas (i.e., temporal and central). The temporal region was associated with cognitive processes involved in the motor action (i.e., explicit knowledge). On the other hand, the central sites were related to the motor control mechanisms per se (i.e., implicit knowledge). The premotor cortex, represented by two frontal regions (i.e., F3–F4 versus F7–F8), showed a decrease on neural activity in the contralateral hemisphere (i.e., to the right hand). This result is in agreement with other experiments suggesting a participation of the frontal cortex in the planning of the apprehension task. This sensorimotor paradigm may contribute to the repertoire of tasks used to study clinical conditions such as depression, alzheimer and Parkinson diseases.  相似文献   
30.
In order to determine the prevalence and risk factors for Chlamydia trachomatis infection in adolescent females and young women in central Brazil, 296 subjects attending two public health services were evaluated. The overall prevalence of C. trachomatis infection, as determined using polymerase chain reaction, was 19.6% (95% confidence interval [CI], 15.3–24.7). In multivariate analysis, young age (odds ratio [OR]adjusted 2.32, 95%CI 1.1–4.8, p<0.05) and having 2–3 (ORadjusted 3.41, 95%CI 1.6–6.3, p<0.05) or ≥4 sexual partners in life (ORadjusted 3.10, 95%CI 1.1–6.3, p<0.05) were factors significantly associated with chlamydial infection. In conclusion, the prevalence of C. trachomatis infection was high in the studied population and risk factors were related to age and sexual behavior.  相似文献   
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