Some aspects of the verb system in the language of deaf students

Approximately 480 deaf students (age 10 to 19 years) and 60 hearing students (age eight to 10 years) were asked to judge the grammaticality of sentences containing auxiliary verbs, of sentences where the verb had been deleted, and of sentences in which the verb tense was not marked. The results indicated that deaf students have considerable difficulty with the verb system of English. This difficulty was most pronounced in the formation of tense and voice and in agreement in number and tense. A possible ordering for the acquisition of tense did emerge; from earliest to latest it is: simple past, future, present progressive, perfective, and passive. Improvement in grammaticality judgments appeared to come from an increase in recognition that incorrect sentences were ungrammatical.     

Gallium citrate Ga 67 scanning: clinical usefulness in lymphoma patients

Gallium citrate Ga 67 (67Ga) scans were performed in 50 consecutive lymphoma patients who underwent routine staging. The overall accuracy of 67Ga scans was greater than 80% for all nodal sites except the spleen (68%). Sensitivity was greater than 88% in the neck and mediastinum, 67% in the abdomen-pelvis, and 33% for the spleen. Specificity was greater than 85% for all nodal sites except for the mediastinum (67%). The accuracy of pedal lymphangiograms was 75%, sensitivity 87%, and specificity 68%. Gallium 67 scans complemented the lymphogram in the abdomen-pelvis but, due to limited sensitivity and high number of equivocal studies (16%), did not replace it. Infraclavicular, pectoral, and mediastinal lesions were detected by 67Ga scans when missed by other means. In 20% to 25% of patients, 67Ga scans provided information not afforded by other diagnostic studies and are therefore considered an important staging procedure for lymphoma patients.     

The relationship of hypercapnic ventilatory responses to age, gender and athleticism

When a gas mixture containing carbon dioxide (CO2) is inhaled by an individual, alveolar ventilation is increased. This ventilatory response to CO2 highlights the relationship between the increase in exercise ventilation and the increase in alveolar CO2 pressure (paCO2). This response is mediated centrally by brainstem chemoreceptors in the medulla and, to a lesser extent, peripherally by the carotid and aortic bodies. However, the response of increased breathing to rising paCO2 varies markedly among individuals. The responses to CO2 rebreathing have been investigated by a variety of research groups for different reasons. The range of responses by children and adults including: gender differences; responses by athletes; the relationship between age and body size; and whether it is an acquired or inherited response have been studied. The following is a summary of these different aspects of CO2 rebreathing has been complied to assist researchers studying any single or multiple facets of the area.     

A randomized comparative study on the safety and efficacy of clarithromycin and erythromycin in treating community-acquired pneumonia

BACKGROUND: Clarithromycin, a new macrolide, has distinct microbiological and pharmacokinetic advantages compared with erythromycin. This study was designed to compare the safety and efficacy of clarithromycin and erythromycin in the treatment of community-acquired pneumonia. METHODS: Forty adult patients, diagnosed with community-acquired pneumonia, were randomly arranged to received either clarithromycin 250 mg twice daily (20 patients) or erythromycin 500 mg four times daily (20 patients), over a period of 14 days each. RESULTS: There were no statistically significant differences between the two groups in terms of clinical cure (65% for clarithromycin, 65% for erythromycin), clinical success (clinical cure and improvement: 95% for clarithromycin, 90% for erythromycin) and radiological response (95% for clarithromycin, 90% for erythromycin). However, adverse effects, mainly gastrointestinal, were significantly higher among patients treated with erythromycin than among patients treated with clarithromycion (p < 0.05). CONCLUSIONS: These results demonstrate that clarithromycin 250 mg twice daily is at least as effective as erythromycin 500 mg four times daily for the treatment of community-acquired pneumonia, and is much better tolerated.     

D2 dopamine receptor antisense oligodeoxynucleotide inhibits the synthesis of a functional pool of D2 dopamine receptors

In vivo administration of an antisense oligonucleotide targeted toward the D2 dopamine (DA) receptor mRNA (D2 AS) markedly inhibited D2 receptor-mediated behaviors but produced only a relatively small reduction in the levels of D2 DA receptors in mouse striatum. This apparent dissociation between DA receptor-mediated behaviors and the levels of D2 DA receptors was addressed by inhibiting the total number of D2 DA receptors by intraperitoneal administration of the selective, irreversibly acting D2 DA receptor antagonist fluphenazine-N-mustard (FNM) and then determining the effects of D2 AS, administered intracerebroventricularly, on the rate of synthesis of D2 DA receptors and on the recovery of D2 receptor-mediated behaviors. FNM inactivated approximately 90% of D2 DA receptors within 4 hr of treatment, after which the receptors returned to normal levels by approximately 8 days. D2 AS treatment significantly inhibited the rate of recovery of D2 DA receptors in striatum of FNM-treated mice. FNM treatment also produced a number of behavioral alterations, including catalepsy, and the inhibition of stereotypic behavior induced by the D2/D3 DA receptor agonist quinpirole. Both of these behaviors returned to normal within 8 days after FNM treatment. D2 AS treatment delayed the restoration of these FNM-induced behaviors. Thus, it reduced the rate of disappearance of the cataleptic behavior induced by FNM and significantly delayed the restoration of the stereotypic behavior induced by quinpirole. The changes induced by D2 AS on D2 receptor-mediated behaviors were reversed on cessation of D2 AS treatment. A random oligomer given in the same amount and for the same length of time as that of the D2 AS had no significant effects on either D2 DA receptor synthesis or DA receptor-mediated behaviors. These studies demonstrate that in vivo administration of D2 AS decreased the rate of recovery of D2 DA receptors and inhibited the recovery of D2 DA receptor-mediated behaviors after irreversible receptor inactivation and suggest that D2 AS treatment inhibits the synthesis of a functional pool of D2 DA receptors.     

Noninvasive measurement of tissue magnesium and correlation with cardiac levels

BACKGROUND: Intracellular magnesium ([Mg]i) plays an important role in the regulation of myocardial metabolism, contractility, and the maintenance of transsarcolemmal and intracellular ionic gradients. An understanding of the role of magnesium in the clinical setting, however, is hampered by the lack of an assay of intracellular tissue magnesium levels. METHODS AND RESULTS: We used energy-dispersive x-ray analysis to measure [Mg]i in sublingual epithelial cells and to correlate the level with those in atrial biopsy specimens from the same patients during cardiopulmonary bypass. Levels were also measured in acute myocardial infarction (AMI) patients before and after intravenous magnesium sulfate administration and compared with those from intensive care unit (ICU) patients and healthy individuals. A strong correlation between sublingual epithelial cell (mean, 32.1 +/- 0.3 mEq/L) and atrial tissue (mean, 32.1 +/- 0.3 mEq/L) [Mg]i was present in 18 cardiac surgery patients (r = .68, P < .002). Epithelial and atrial [Mg]i levels were lower than in healthy individuals (33.7 +/- 0.5 mEq/L, P < .01) studied at that time and correlated poorly with serum magnesium. Mean [Mg]i in 22 AMI patients was 30.7 +/- 0.4 mEq/L, which was significantly lower than in 21 ICU patients and 15 healthy individuals (35.0 +/- 0.5 mEq/L and 34.5 +/- 0.7 mEq/L, respectively, P < .001). Intravenous magnesium sulfate was administered to most of the AMI patients (mean dose, 36 +/- 6 mmol). [Mg]i rose significantly in the AMI patients over the first 24 hours, and the magnitude of the increase was greater in those who received higher doses of intravenous magnesium sulfate. CONCLUSIONS: Sublingual epithelial cell [Mg]i correlates well with atrial [Mg]i but not with serum magnesium. [Mg]i levels are low in patients undergoing cardiac surgery and those with AMI. Intravenous magnesium sulfate corrects low [Mg]i levels in AMI patients. Energy-dispersive x-ray analysis determination of sublingual cell [Mg]i may expedite the investigation of the role of magnesium deficiency in heart disease.     

Thermonuclear reaction rates V

Analytic expressions are given for the reaction rates of astrophysically important thermonuclear reactions involving low-mass nuclei (1 Z 14). Numerical values of the rates are tabulated for the temperature range 10⁶ T 10¹⁰ K. This provides a comprehensive update of our previous publications.