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OBJECTIVES: To review the literature on the use of hypertonic saline (HS) in treating cerebral edema and intracranial hypertension. DATA SOURCES: Review of scientific and clinical literature retrieved from a computerized MEDLINE search from January 1965 through November 1999. STUDY SELECTION: Pertinent literature is referenced, including clinical and laboratory investigations, to demonstrate principles and efficacy of treatment with HS in patients with intracranial space-occupying pathology. DATA EXTRACTION: The literature was reviewed to summarize the mechanisms of action, efficacy, adverse effects, systemic effects, and comparisons with standard treatments in both clinical and laboratory settings. DATA SYNTHESIS: HS has an osmotic effect on the brain because of its high tonicity and ability to effectively remain outside the bloodbrain barrier. Numerous animal studies have suggested that fluid resuscitation with HS bolus after hemorrhagic shock prevents the intracranial pressure (ICP) increase that follows resuscitation with standard fluids. There may be a minimal benefit in restoring cerebral blood flow, which is thought to be mitigated through local effects of HS on cerebral microvasculature. In animal models with cerebral injury, the maximum benefit is observed in animals with focal injury associated with vasogenic edema (cryogenic injury). The ICP reduction is seen for < or =2 hrs and may be maintained for longer periods by using a continuous infusion of HS. The ICP reduction is thought to be caused by a reduction in water content in areas of the brain with intact blood-brain barrier such as the nonlesioned hemisphere and cerebellum. Most comparisons with mannitol suggest almost equal efficacy in reducing ICP, but there is a suggestion that mannitol may have a longer duration of action. Human studies published to date reporting on the use of HS in treating cerebral edema and elevated ICP include case reports, case series, and small controlled trials. Results from studies directly comparing HS with standard treatment in regard to safety and efficacy are inconclusive. However, the low frequency of side effects and a definite reduction of ICP observed with use of HS in these studies are very promising. Systemic effects include transient volume expansion, natriuresis, hemodilution, immunomodulation, and improved pulmonary gas exchange. Adverse effects include electrolyte abnormalities, cardiac failure, bleeding diathesis, and phlebitis. Although unproven, a potential for central pontine myelinolysis and rebound intracranial hypertension exists with uncontrolled administration. CONCLUSIONS: HS demonstrates a favorable effect on both systemic hemodynamics and intracranial pressure in both laboratory and clinical settings. Preliminary evidence supports the need for controlled clinical trials evaluating its use as resuscitative fluid in brain-injured patients with hemorrhagic shock, as therapy for intracranial hypertension resistant to standard therapy, as firstline therapy for intracranial hypertension in certain intracranial pathologies, as small volume fluid resuscitation during spinal shock, and as maintenance intravenous fluid in neurocritical care units.  相似文献   
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BackgroundNew-onset diabetes after renal transplantation (NODAT) is one of the most frequent metabolic complications after transplantation; it is present in ~25% of kidney transplant recipients, increasing their cardiovascular risk and inducing graft damage. The medical approach of this entity is still a matter of controversy, so our aim was to review the evidence available and offer a practical approach for diagnosis, treatment, and follow-up.MethodsA systematic review of the literature in the Medline, Embase, Cochrane, and Lilacs databases was carried out with the use of the terms “Diabetes Mellitus,” “Kidney Transplantation,” “Drug Therapy,” “Prognosis,” “Therapeutics,” and “Risk Factors.” Randomized controlled trials, meta-analyses, and observational studies were included.ResultsThe main risk factors were elevated body mass index, family history of diabetes, recipient >60 years old, hepatitis C virus infection, and treatment with tacrolimus/corticosteroids or sirolimus. Some small studies suggest that thiazolidinediones, sulfonylureas, glinides, and dipeptidyl peptidase 4 inhibitors could be useful in the treatment of the disease. NODAT constitutes a prognostic factor for the renal transplant. Although there is a higher risk of developing diabetes in kidney transplant recipients than in the general population, both populations share the same diagnostic criteria.ConclusionsThere is no consensus on the treatment regimen for these patients. It is necessary to review the diagnostic criteria and the screening methods for NODAT, given the higher susceptibility of kidney transplant recipients to develop this entity; therefore, an earlier intervention could be implemented to decrease the negative effects that this disease has on the kidney graft and the recipient.  相似文献   
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Project Kealahou (PK) is a six-year, federally-funded program aimed at improving services and outcomes for Hawai‘i''s female youth who are at risk for running away, truancy, abuse, suicide, arrest and incarceration. PK builds upon two decades of sustained cross-agency efforts among the state''s mental health, juvenile justice, education, and child welfare systems to promote system-of-care (SOC) principles of community-based, individualized, culturally and linguistically competent, family driven, youth-guided, and evidence-based services. In addition, PK emphasizes trauma-informed and gender-responsive care in serving its target population of females ages 11–18 years who have experienced psychological trauma.Results from the first four years of the implementation of PK in the Department of Health''s (DOH) Child and Adolescent Mental Health Division (CAMHD) highlight the serious familial, socioeconomic, functional, and interpersonal challenges faced by the young women who receive services in Hawai‘i''s SOC. Despite the challenges faced by PK youth and their families, preliminary results of the evaluation of PK show significant improvements across multiple clinical and functional domains of service recipients. A financial analysis indicates that these outcomes were obtained with a minimal overall increase in costs when compared to standard care alone. Overall, these results suggest that PK may offer a cost effective way to improve access, care, and outcomes for at-risk youth and their families in Hawai‘i.  相似文献   
66.
Cytogenetic studies in non-African Burkitt lymphoma   总被引:4,自引:0,他引:4  
Douglass  EC; Magrath  IT; Lee  EC; Whang-Peng  J 《Blood》1980,55(1):148-155
A particular translocation between chromosomes 8 and 14 has been found repeatedly in cytogenetic studies of Burkitt lymphoma, both of African and non-African origin. We report here our findings in cytogenetic studies of direct tumor preparations from 18 non-African Burkitt lymphoma patients, 9 of whom also had cell lines available for study. A t(8;14) was found in direct tumor material in 10 of the 18 patients. Seven of the 9 cell lines had a t(8;14). A total of 15 patients had either a t(8;14) or a 14q+ present in tumor material and/or cell lines. In addition, 8 patients had a peculiar marker chromosome 1. The t(8;14) was not found in every malignant cell and, where present, it was rarely the sole karyotypic abnormality. The relationship of the t(8;14) to the evolution of the tumor is discussed.  相似文献   
67.
Ambulatory continuous ECG and arterial pressure (BP) were recorded simultaneously (Delmar Avionics Pressurometer II) for 24 hours in 13 age-matched normotensive subjects, 11 patients with borderline hypertension (HBP), and in 10 patients with uncomplicated established essential HBP. Urinary concentrations of epinephrine, norepinephrine, and dopamine were simultaneously collected over four successive 4-hour periods and one 8-hour period. Prevalence and total number of ventricular and supraventricular ectopic beats was low and not affected by arterial BP. Twenty-four-hour heart rate (HR) and 4-hourly excretion of epinephrine, norepinephrine, and dopamine were comparable between normotensive and HBP persons and no correlation between urinary catecholamines and arterial BP (systolic, diastolic, or mean), HR, or prevalence of ectopic beats was found in any of the three groups or in the total study population. We conclude that HBP patients without ECG evidence of left ventricular hypertrophy do not have a higher prevalence of supraventricular or ventricular ectopic beats. Urinary catecholamines are not related to circadian fluctuations or variability in arterial BP, HR, or prevalence of ectopic beats.  相似文献   
68.
Dose-response curves of interferons in different sensitive cells are regularly sigmoidal. In somatic monkey-mouse hybrid cells, however, a significant decrease in the slope of the curve for primate interferon was observed, while the dose-response effect was unaltered for mouse interferon. High concentrations of primate interferon were 10- to 100-times less effective in hybrid clones than in parental monkey CV-1 cells; at low concentrations the antiviral effect was 10- to 20-times higher in hybrid clones than in the parental cells. The receptor(s) for primate interferon located on the cell membrane was destroyed by trypsin but not by EDTA. Similarly, acid pH inactivated these receptor sites. We, thus, postulate that the antiviral effect is, at least partially, related to the amount of interferon taken up by the cells. Uptake could be conditioned by active cooperation of two cell-specific factors: a receptor and an activator. The activator might be missing or inactivated for primate interferon in the hybrid cells. We suggest that the putative antiviral protein is not cell-species specific, and that information for its synthesis in the hybrid cells might be located on a mouse rather than a monkey chromosome.  相似文献   
69.
Poorly absorbed bismuth preparations may benefit a variety of chronic colonic conditions including ulcerative colitis. Bismuth-induced neurotoxicity is a potential complication of the chronic use of these preparations, and a less-absorbable form of bismuth is needed. If bismuth absorption occurs primarily in the upper gut, a delayed-release bismuth preparation could reduce absorption. We studied the site of bismuth absorption from bismuth subsalicylate (BSS) in rats. For 15 days, BSS (50 mg/day) was ingested or infused directly into the cecum via a chronically implanted cannula. Oral BSS resulted in serum and urine bismuth levels many times higher (3.5 ± 0.3 g/liter and 1570 ± 286 g/g creatinine, respectively) than with cecal administration (undetectable (<1.5 g/liter) and 75 ± 25 g/g creatinine). Thus, bismuth absorption from BSS occurred almost entirely in the upper gut. These findings provide a rationale for a similar study of delayed-release bismuth preparations in humans.  相似文献   
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