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Selenium status of malnourished hospitalized patients   总被引:1,自引:0,他引:1  
We evaluated selenium (Se) status of 44 hospitalized patients with protein-energy malnutrition. The patients were assigned to "normal" or "low" Se groups-1 and 2, respectively-based on whether the plasma Se level exceeded or was below the value of the mean-2SD of healthy Georgians'. Plasma and erythrocyte Se levels correlated significantly (r = .52, P less than .01). Erythrocyte glutathione peroxidase activity was highly correlated with plasma Se (r = .68) in group 2; there was no significant correlation between these parameters in group 1. In group 2 the mean plasma prealbumin level was significantly lower, and the mean corpuscular volume and serum glutamic oxaloacetic transaminase level were significantly higher compared to group 1. Other nutritional parameters did not correlate with Se status. Concomitant deficiencies of other nutrients were common in both patient groups. Se levels may relate to protein status, and abnormal hematologic and hepatic parameters may reflect low Se status and/or protein-energy malnutrition. Low Se status is common in malnourished patients from a low Se area, and Se supplementation should be included in their nutritional-repletion regimens.  相似文献   
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Reproductive effects of four phthalic acid esters in the mouse   总被引:7,自引:0,他引:7  
These studies compared the reproductive toxicity of four phthalates by a continuous breeding protocol. Mice were given diets with diethyl phthalate (DEP) (0.0, 0.25, 1.25, or 2.5%), di-n-butyl phthalate (DBP) (0.0, 0.03, 0.3, or 1.0%), di-n-hexyl phthalate (DHP) (0.0, 0.3, 0.6, or 1.2%), or di(2-ethylhexyl) phthalate (DEHP) (0.0, 0.01, 0.1, or 0.3%). Both male and female CD-1 mice were dosed for 7 days prior to and during a 98-day cohabitation period. Reproductive function was evaluated during the cohabitation period by measuring the numbers of litters per pair and of live pups per litter, pup weight, and offspring survival. There was no apparent effect on reproductive function in the animals exposed to DEP, despite significant effects on body weight gain and liver weight. DBP exposure resulted in a reduction in the numbers of litters per pair and of live pups per litter and in the proportion of pups born alive at the 1.0% amount, but not at lower dose levels. A crossover mating trial demonstrated that female mice, but not males, were affected by DBP, as shown by significant decreases in the percentage of fertile pairs, the number of live pups per litter, the proportion of pups born alive, and live pup weight. DHP in the diet resulted in dose-related adverse effects on the numbers of litters per pair and of live pups per litter and proportion of pups born alive at 0.3, 0.6, and 1.2% DHP in the diet. A crossover mating study demonstrated that both sexes were affected. DEHP (at 0.1 and 0.3%) caused dose-dependent decreases in fertility and in the number and the proportion of pups born alive. A crossover mating trial showed that both sexes were affected by exposure to DEHP. These data demonstrate the ability of the continuous breeding protocol to discriminate the qualitative and quantitative reproductive effects of the more and less active congeners as well as the large differences in reproductive toxicity attributable to subtle changes in the alkyl substitution of phthalate esters.  相似文献   
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Serial changes in various markers of disease activity with corticosteroid therapy were assessed in 12 patients with active sarcoidosis. After six weeks of treatment with 40 mg daily of prednisone, all but one patient demonstrated symptomatic and radiographic improvement. For the entire patient group, there were corresponding improvements in forced vital capacity, from 59.2 +/- 5.5 to 70.5 +/- 5.3 percent of the predicted value (p less than 0.001, Student paired t test), serum angiotensin-converting enzyme levels, from 66.0 +/- 12.1 to 28.2 +/- 4.0 U/ml (p = 0.003), 67gallium lung scanning scores, from 3.6 +/- 0.2 to 0.8 +/- 0.3 (p less than 0.001), serum gamma globulin levels, from 2.40 +/- 0.2 to 1.5 +/- 0.1 g/dl (p less than 0.001), and erythrocyte sedimentation rate, from 26.8 +/- 2.7 to 14.8 +/- 3.0 mm per hour (p less than 0.001). Changes in percent of bronchoalveolar lavage fluid lymphocytes were less impressive (from 28.7 +/- 4.9 to 21.2 +/- 5.1, p = 0.034), but the geometric mean number of bronchoalveolar lavage fluid-IgG-secreting cells decreased from 23,861 to 3,830 (p = 0.013). Serial evaluations in five patients treated with decreasing doses of alternate-day prednisone for an additional 10 1/2 months indicated that changes in 67gallium lung scanning scores corresponded most closely to the clinical course in five of five patients. Determination of serum angiotensin-converting enzyme levels also closely paralleled the clinical course in four of five patients, whereas the other parameters measured were more variable markers of clinical response. However, abnormalities of bronchoalveolar lavage fluid-IgG-secreting cells often persisted in the absence of clinically evident disease, and the percentages of bronchoalveolar lavage fluid lymphocytes were frequently normal in patients who responded subsequently to corticosteroids. Larger prospective studies are warranted to more extensively evaluate various measurements of disease activity, especially bronchoalveolar lavage fluid analysis, in sarcoidosis.  相似文献   
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Prevalence of viral respiratory tract infections in children with asthma   总被引:1,自引:0,他引:1  
BACKGROUND: Previous studies support a strong association between viral respiratory tract infections and asthma exacerbations. The effect of newly discovered viruses on asthma control is less well defined. OBJECTIVE: We sought to determine the contribution of respiratory viruses to asthma exacerbations in children with a panel of PCR assays for common and newly discovered respiratory viruses. METHODS: Respiratory specimens from children aged 2 to 17 years with asthma exacerbations (case patients, n = 65) and with well-controlled asthma (control subjects, n = 77), frequency matched by age and season of enrollment, were tested for rhinoviruses, enteroviruses, respiratory syncytial virus, human metapneumovirus, coronaviruses 229E and OC43, parainfluenza viruses 1 to 3, influenza viruses, adenoviruses, and human bocavirus. RESULTS: Infection with respiratory viruses was associated with asthma exacerbations (63.1% in case patients vs 23.4% in control subjects; odds ratio, 5.6; 95% CI, 2.7- 11.6). Rhinovirus was by far the most prevalent virus (60% among case patients vs 18.2% among control subjects) and the only virus significantly associated with exacerbations (odds ratio, 6.8; 95% CI, 3.2-14.5). However, in children without clinically manifested viral respiratory tract illness, the prevalence of rhinovirus infection was similar in case patients (29.2%) versus control subjects (23.4%, P > .05). Other viruses detected included human metapneumovirus (4.6% in patients with acute asthma vs 2.6% in control subjects), enteroviruses (4.6% vs 0%), coronavirus 229E (0% vs 1.3%), and respiratory syncytial virus (1.5% vs 0%). CONCLUSION: Symptomatic rhinovirus infections are an important contributor to asthma exacerbations in children. CLINICAL IMPLICATIONS: These results support the need for therapies effective against rhinovirus as a means to decrease asthma exacerbations.  相似文献   
8.

Background and Objectives:

Surgeons constantly struggle with the formation of condensation on the lens of a laparoscope, which prolongs procedures and reduces visibility of the abdominal cavity. The goal of this project was to build a device that would direct a flow of carbon dioxide (CO2) into an open chamber surrounding the lens of a laparoscope, acting to keep moisture away from the lens and eliminate condensation.

Methods:

The device isolates the lens of the laparoscope from the humid environment of the intraperitoneal cavity by creating a microenvironment of dry CO2. This was accomplished by building a communicating sleeve that created an open chamber around the distal 2 to 3 cm of the scope. Into this cavity, dry cool CO2 was pumped in from an insufflator so that the path of the gas would surround the lens of the scope and escape through a single outlet location through which the scope views the intraperitoneal cavity. This chamber is proposed to isolate the lens with a high percentage of dry CO2 and low humidity. The device was tested in 7 different adverse conditions that were meant to challenge the ability of the device to maintain the viewing field with no perceptible obstruction.

Results:

In all of the conditions tested, 25 trials total, the device successfully prevented and/or eliminated laparoscopic lens fogging.

Conclusions:

The device designed for this project points to the potential of a simple and effective mechanical method for eliminating laparoscopic lens fogging.  相似文献   
9.
Germ-line events, such as paternal mutation or genomic imprinting, contribute to the early onset of childhood cancers such as retinoblastoma, Wilms tumors, and neuroblastoma. Given the high frequency of deletion involving chromosome 9p in childhood acute lymphoblastic leukemia (ALL), this study investigated whether 9p deletion might reflect preexisting germ-line gene inactivation. To do this the parental origin of deletion was determined in 10 cases of ALL with 9p21 loss of heterozygosity. Of these cases, 9 showed loss of the maternally derived allele, suggesting that a germ-line event involving a 9p gene may play a role in the onset of childhood ALL.  相似文献   
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