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991.
Suicide is a major source of morbidity and mortality in patients with mental illness. The selective serotonin reuptake inhibitors (SSRIs) and other newer nontricyclic antidepressants appear to have less clinically significant toxicity in overdose, resulting in lower costs of treatment when compared with tricyclic antidepressant (TCA) overdoses. The resource utilization and cost of treatment for SSRI overdoses may not be less if (1) these agents are commonly ingested with other potentially toxic substances, or (2) health care practices have not changed in response to the apparent greater safety of SSRIs. This study evaluates demographic variables of antidepressant overdoses to determine whether differences exist in treatments and monitoring. Additionally, this study evaluates costs associated with care and the impact of co-ingestants on those same factors.  相似文献   
992.
BACKGROUND: Critical assessment of diagnostic accuracy is indispensable to resident training and medical education, especially in regard to our situation of the extremely low rate of autopsy. Recent setup of advanced technology for neurological diagnosis has resulted in a tendency to overuse these tools at the expense of using classic bedside diagnostic approach. Disclosing the common errors of daily practices among neurological residents necessitates implementing this pioneer study. METHODS: The tentative diagnosis of each patient, as performed by neurological residents after finishing bedside diagnostic processes, was assessed by final diagnosis concluded from clinical syndrome and/or the results of laboratory studies. The overall rate of diagnostic error and the frequency of diagnostic inaccuracy in various disease entities were evaluated. The reason for the diagnostic error was determined by reviewing the records regarding the entire diagnostic process. RESULTS: 1336 consecutive patients from January 1990 to December 1990 were recruited for this study. The initial bedside diagnosis was correct in 901 (67%) patients. No definite final diagnosis could be obtained in 169 (13%) patients. The diagnoses were incorrect in 266 (20%) patients. The highest rate of inaccuracy was found in the diagnosis of subdural hematoma (56%). The other common diseases of high rate of diagnostic inaccuracy were myasthenia gravis (50%), subarachnoid hemorrhage (42%), Guillain-Barré syndrome (40%), traumatic disorders (39%), herniation of intervertebral disc (33%), metabolic encephalopathy (30%), infection of central nervous system (30%), intracranial neoplasm (24%), drug overdose or intoxication (22%), and mixed neurological and metabolic encephalopathy (21%). The explored reasons for diagnostic inaccuracy were errors of reasoning (38%), inadequate data base (35%), and inadequate fund of knowledge (27%). CONCLUSIONS: This study confirmed that the basic methods of bedside diagnosis with a standardized sequence of history taking, physical examination and diagnostic reasoning are currently still the most fundamental process of achieving an accurate diagnosis in neurological emergencies. No shortcut or mechanical substitute is available for clinical diagnosis.  相似文献   
993.
A decrease in plasma HDL cholesterol concentration is considered as a major cardiovascular risk factor and is a prevalent lipid abnormality among patients with coronary heart disease. This condition is most often observed in the presence of hypertriglyceridaemia, generally linked to the insulin resistance syndrome, but may also be associated to elevated LDL cholesterol level or even be present alone (hypoalphalipoproteinaemia). The decision to treat a patient with low HDL level depends on the individual overall cardiovascular risk which should be evaluated as carefully as possible. The investigation should look for causes which may favour this metabolic condition, such as bad life habits or possible pharmacological interferences.  相似文献   
994.
995.
A small study was performed to examine whether the instillation of ricin toxoid vaccine into the lungs of Porton rats offered protection from lethal effects of subsequent intratracheal challenge with ricin toxin. Further the immune response to liposomally-encapsulated vaccine and the protection offered was compared with vaccine either adsorbed to Alhydrogel adjuvant or as a simple aqueous solution. The formaldehyde-treated ricin toxin vaccine (RTV) was administered at two dose levels, 500 and 100 micrograms kg-1 body weight to groups of rats, on two occasions by intratracheal instillation. Liposomally-encapsulated vaccine (LRTV) produced a higher titre of ricin-specific antibodies than Alhydrogel-vaccine (ARTV) and vaccine solution. When challenged with 3 LD50 of ricin by intratracheal instillation 7 weeks after the second vaccine instillation, all rats in both LRTV dose groups survived with minimal signs of incapacitation. Analysis of antibody secretion by spleen cells, 14 days post challenge, showed that the IgG isotype in the LRTV group was significantly higher than that in the ARTV and RTV groups and also that the proportion of specific IgA in lung fluid was higher in the LRTV group than in the ARTV and RTV groups. The results of this study indicate that effective vaccinations against inhaled ricin could be achieved with liposomally-encapsulated ricin toxoid, via the lung and should be investigated further.  相似文献   
996.
STUDY OBJECTIVE: To evaluate histologic, microbiological, and clinical criteria in the recognition of ventilator-associated pneumonia (VAP) in patients who died while mechanically ventilated. METHODS: The study group consisted of 39 patients who died after a mean of 14 days of mechanical ventilation. Postmortem fiberoptic bronchoscopy (FOB) and open lung biopsy were performed with collection of specimens initiated <1 h after death. The microbiological specimens included suction catheter aspirate of tracheal secretions, FOB-guided protected specimen brush (PSB) of tracheal secretions, blindly placed PSB in a distal airway, FOB-guided PSB in a distal airway, and FOB-guided BAL fluid (BALF) in a distal airway. Qualitative bacteriologic study was performed on all specimens, and quantitative bacteriologic study was performed on all but the suction catheter aspirate of the trachea. A biopsy specimen of peripheral lung parenchyma from the same region sampled by FOB was sent for quantitative culture and histologic analysis. The BALF was analyzed for cell population and percent of neutrophils containing intracellular organisms. The clinical criteria selected for comparison with histologic and microbiological results included a temperature > or =38.5 degrees C during the 48 h prior to death, a WBC count > or =15,000/mm3 in the 48 h prior to death, presence of a bacterial or fungal pathogen on the last sputum culture, radiographic worsening in the week prior to death, and worsening gas exchange defined as a 15% decrease in the PaO2/fraction of inspired oxygen ratio in the 72 h prior to death. RESULTS: None of the quantitative cultures had a reliable positive predictive value for histologic pneumonia. None of the five clinical criteria tested showed agreement with the presence or absence of histologic pneumonia. There was a significant correlation between qualitative and quantitative microbiological results from the distal airway/FOB-guided PSB, distal airway/BALF, and quantitative culture of the lung parenchyma. Also, suction catheter aspirate of the trachea had a sensitivity of 87% in recognizing the bacterial species simultaneously present in lung parenchyma. None of the patients with histologic pneumonia had <50% neutrophils in the BALF. CONCLUSIONS: Neither the bacterial, density from the four airway quantitative cultures, nor the bacterial density from quantitative culture of lung parenchyma accurately separated the histologic pneumonia and nonpneumonia groups. No clinical criteria or combination of clinical criteria correlated with the presence or absence of histologic pneumonia. A BALF with <50% neutrophils had a 100% negative predictive value for histologic pneumonia. A BALF quantitative culture had a sensitivity of 63%, specificity of 96%, and positive predictive value of 91% in recognizing sterile lung parenchyma. Thus, BALF may have a role in excluding pneumonia/infection in the ventilated patient. Antibiotic choice for the empiric therapy of VAP can be accurately guided by the microbial population recognized through culture of a tracheal suction catheter aspirate.  相似文献   
997.
OBJECTIVE: To identify factors contributing to infective endocarditis at a major teaching hospital. METHODS: Retrospective review of clinical records of patients diagnosed with endocarditis by standard case definitions with respect to causative organisms, clinical features and outcome. RESULTS: One hundred and ninety-three episodes of endocarditis seen between 1979 and 1992 at Westmead Hospital, Sydney, were reviewed. In the 174 cases where the causative organism was isolated, 75 (43%) were Staphylococcus aureus and 50 (29%) were viridans streptococci. Nosocomial acquisition and/or inter-hospital transfer accounted for 83 episodes; 48 (58%) S. aureus (P < 0.001) and nine (11%) viridans streptococci (P < 0.001). In cases from the local community, viridans streptococci were more common than S. aureus (37% versus 25%); these included 18 episodes (14 S. aureus) in intravenous drug users. CONCLUSION: We conclude that, compared with community-acquired infections, the aetiology of endocarditis in a large teaching hospital is influenced strongly by the prevalence of nosocomial endocarditis and the need for interhospital transfer of complicated cases.  相似文献   
998.
The distribution of the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) was studied immunocytochemically in bovine ovaries from 3 mo of gestation up to and including puberty, and from adult cows at three stages of the estrous cycle. The appearance of VIP and NPY immunoreactivity of 4.5-6 mo of gestation coincided with the onset of follicular development. In contrast to NPY, VIP was first found in the cortex. Both VIP and NPY immunoreactivity increased with age. From 9 mo of gestation onwards, VIP and NPY were found around blood vessels and non-vascular smooth muscle cells, in the stroma near preantral follicles, and in the theca externa of antral follicles. In addition, VIP-positive cells were observed exclusively in the granulosa layer of the preovulatory follicle at the time of the LH surge. The distribution of VIP- and NPY-immunoreactive fibers in the ovary may point to an effect of these neuropeptides on various physiological processes, including follicle development and ovarian blood flow. In addition, the presence of VIP-positive cells in the granulosa layer of the preovulatory follicle is indicative of a role for VIP in ovulation.  相似文献   
999.
1000.
OBJECTIVES: To identify the causes of and discuss nursing management of those complications that are unique to the brain tumor patient population. DATA SOURCES: Published articles and books related to neurological and nonneurological complications in the neuro-oncology patient. CONCLUSIONS: Seizures, cerebral edema, thromboembolism, and endocrine dysfunction are several complications experienced by the neuro-oncology patient. These complications can be caused by the tumor or treatment of this disease. IMPLICATIONS FOR NURSING PRACTICE: Care of the neuro-oncology patient is complex. Knowledge of the potential complications that patients may experience and how to manage these problems serves to enhance their quality of life.  相似文献   
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