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991.
Presented is the case of a normal two-month-old girl who developed seizures secondary to water intoxication. The infant had been fed 20 to 30 oz of water daily for three days, while her usual formula was withheld because of vomiting and diarrhea. On the day of admission, the infant exhibited signs of water intoxication in the form of lethargy, vomiting, and seizures. Hyponatremia, hypothermia, and hyperglycemia were noted on admission, and are common features of the syndrome. The patient responded well to fluid restriction and salt replacement. Previous reports have attributed water intoxication to feeding mismanagement, vigorous hydration, dilute formulas, and swimming lessons.  相似文献   
992.
The incidence and prevention of systemic embolism in patients with chronic left ventricular aneurysm have been controversial. This retrospective study investigated the incidence of clinically evident embolic events and the effect of oral anticoagulation in patients with unequivocal angiographically defined left ventricular aneurysm. Between 1971 and 1979, 76 patients met the ventriculographic criteria and received initial medical management. The median interval from myocardial infarction to ventriculography was 11 months (range 1 month to 16 years) and subsequent median follow-up time was 5 years. Twenty patients receiving anticoagulant therapy were followed up for a total of 40 patient-years and 69 patients not on anticoagulant therapy were followed up for a total of 288 patient-years; 13 patients were included in both subsets. Twenty-eight patients died during follow-up and the 3 and 5 year survival rates were 75 and 61%, respectively. Only one patient not receiving anticoagulant therapy had a clinical embolic event, resulting in an incidence of 0.35 per 100 patient-years. Therefore, in the absence of other predisposing conditions, the extremely low incidence of systemic emboli in these patients with chronic (first documented at least 1 month after myocardial infarction) left ventricular aneurysm does not justify the use of long-term oral anticoagulant therapy.  相似文献   
993.
The serologic and viral profiles of 24 patients who presented with acute hepatitis B virus (HBV) infection were studied. Although in rare cases, HBV-DNA was detectable before hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), in the majority the viral proteins appeared first. In acute hepatitis followed by recovery, as IgM anti-HBc (hepatitis B core antigen) titres rose, the level of HBV replication fell and serum transaminases became elevated. In patients progressing to chronic HBV infection, IgM anti-HBc titres rose early, viral replication was initially low but continued to rise as the serum transaminase levels became elevated. 7S IgM anti-HBc, although present in the phase of established chronic HBV infection, was not found in the early phase of the chronic infection. Thus this antibody appears to be a consequence of, rather than a causative factor in, chronic HBV infection.  相似文献   
994.
The effect of cost containment on the practice of cardiology: predictions   总被引:1,自引:0,他引:1  
When health care cost containment is tied to unit pricing, the system may become price-driven rather than care-driven. Although the incentives engendered by unit pricing may not necessarily result in practices detrimental to the young or the patient with relatively pure disease, the potential for adverse effects on the elderly, the poor and the chronically ill is real. Hospitals will soon emphasize quick turnover, efficiency and intensive care. Diagnostic evaluations and chronic disease care will be moved out of hospitals into physician owned-and-operated facilities and out-of-hospital settings, respectively. The health care system will fractionate, and quality control will require restructuring to achieve the present level of quality assurance. Cardiologists, as well as other physicians, will need to alter their teaching style and teaching locations. Better methods for predicting outcomes will need to be developed; we will no longer have the safety net of following a patient closely and altering management plans according to the patient's response. Cost containment may occur under diagnosis related groups, preferred provider organizations, health maintenance organizations and other prepaid or "capped" systems. There are, however, many issues relative to cost versus quality that need to be resolved if severe detrimental effects on care are to be avoided.  相似文献   
995.
Pneumococcal sepsis is a life-threatening complication in splenectomised patients even since the introduction of a polyvalent pneumococcal vaccine. Eight episodes of pneumococcal sepsis in seven properly vaccinated splenectomised patients are described. All but two of the causative serotypes were included in the vaccine. The fact that most of the patients were immunosuppressed may explain the failure of the vaccine in these particular patients. A survey of 59 episodes of pneumococcal bacteraemia during 1982 at the Soroka Medical Center, however, shows that 32% of the strains of pneumococci isolated were among seven types not included in the vaccine. The addition of continuous antibiotic prophylaxis in vaccinated and splenectomised patients is suggested.  相似文献   
996.
Arterial blood gases are difficult to obtain during cardiopulmonary resuscitation (CPR) in human beings, and the possibility of venous sampling is raised frequently. The reliability of central venous gases as a substitute for arterial blood gases in assessing acid base status, however, has not been investigated adequately under conditions of CPR. Therefore, femoral arterial and central venous catheters were placed in 24 mongrel dogs, and ventricular fibrillation was electrically induced. After varying predetermined downtimes from five to 60 minutes, open-chest CPR was begun, and arterial and central venous blood gases were simultaneously drawn every five minutes during a 30-minute period. Arterial pH (pHa) was consistently higher than central venous pH (pHcv) by an average of .048 units. A significant correlation existed between the pHa and pHcv at all times during CPR, with an overall r = .9771 (P less than .0001). The difference between central venous PCO2 (PcvCO2) and arterial PCO2 (PaCO2) was 5.17 mm Hg prior to cardiac arrest, but it increased 300% to a mean of 15.51 mm Hg during CPR. Correction of pHcv using conventional methods to account for this respiratory component decreased the correlation between pHa and pHcv to r = .6905. The ability of pHcv to substitute for pHa was assessed, and showed a sensitivity of 100% when pHa of 7.2 was used as a criterion for treatment. In this model, pHcv is a sensitive indicator of pHa and it may be used to guide bicarbonate therapy. The increased PcvCO2 during CPR probably results from the marked tissue lactic acid production and subsequent shift of the bicarbonate buffer into free carbon dioxide.  相似文献   
997.
The use of carbamazepine (CBZ) and oxcarbazepine (OXC) as first‐line antiepileptic drugs in the treatment of focal epilepsy is limited by hyponatremia, a known adverse effect. Hyponatremia occurs in up to half of people taking CBZ or OXC and, although often assumed to be asymptomatic, it can lead to symptoms ranging from unsteadiness and mild confusion to seizures and coma. Hyponatremia is probably due to the antidiuretic properties of CBZ and OXC that are, at least partly, explained by stimulation of the vasopressin 2 receptor/aquaporin 2 pathway. No known genetic risk variants for CBZ‐ and OXC‐induced hyponatremia exist, but likely candidate genes are part of the vasopressin water reabsorption pathway.  相似文献   
998.
999.
1000.
There are two popular strategies for current drug treatment of epilepsy; starting early may be better and polytherapy conveys advantages over monotherapy. This review briefly examines if the historical record is much of a guide to determine the clinical value of these two strategies. Great clinical scientists of the 19th and early 20th century, such as Sir William Gowers, and William Aldren Turner, offered vivid single case studies and showed early results of seizure remission in groups of subjects. The historical record offered, however, no evidence of clear clinical benefits for early treatment and polytherapy. Combination treatment was thought to be useful in only some cases. In agreement, current evidence shows no clear clinical benefit of starting treatment early, except perhaps in severe epilepsy. Polytherapy is clinically useful in a subgroup of subjects, but despite being a standard treatment strategy for over one hundred years, it has been poorly studied. In fact, there is no compelling experimental or clinical evidence for a difference in seizure outcome between monotherapy and polytherapy. This surprising finding should prompt a re‐appraisal regarding the need to test both strategies separately for the licensing of new antiepileptic drugs.  相似文献   
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