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41.
Background: Chronotherapy studies with inhaled corticosteroids have shown optimal therapeutic benefit when steroids are administered four times per day (QID) or once daily at 3 PM.Objective: This study evaluated whether more convenient once-daily dosage times (8 AM and 5:30 PM) produce improvement in asthma equivalent to QID.Methods: Efficacy outcome measures included FEV1, peak expiratory flow rates, bronchial responsiveness, use of β2-agonists, nocturnal awakenings, and responses to a quality of life questionnaire. Systemic effects were blood eosinophil count, cortisol level, 24-hour urinary cortisol, and evaluation for oral candidiasis and dysphonia.Results: Baseline measurements for all three treatment groups were similar. For morning peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.001) and the 5:30 PM group (p = 0.003), but not the 8 AM group (p = 0.75). For evening peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.005) and the 5:30 PM group (p = 0.01), but not for the 8 AM group (p = 0.47). There were significant improvements in all other outcome variables for each group except PC20. There was a significant improvement in PC20 only in the QID group. The systemic effects of the three regimens were comparable.Conclusion: Dosing of inhaled steroid at 5:30 PM had no increased systemic effects and produced efficacy similar to QID dosing. Dosing at 8 AM did not produce results consistently comparable to QID dosing. Optimal once-daily dosing of inhaled steroid is between 3 PM and 5:30 PM.  相似文献   
42.
Hitherto, various critics have claimed that the most commonly used measure for daily hassles is confounded with psychological well-being in both content and format. In order to circumvent such contamination, the Survey of Recent Life Experiences (SRLE) was developed by Kohn and MacDonald (1992). In the present study, the SRLE was psychometrically evaluated within a general sample of the Dutch population. Confirmatory factor analysis showed that, with the exception of one item, the original six-factor structure was strongly replicated. For five of six factors, internal consistency reliabilities proved satisfactory. It is argued that the rather low internal consistency reliability of the sixth factor may be improved if additional items are subjoined. In addition, yielded relationships between the SRLE and other variables were in accordance with previous research. It is therefore argued that the results are in support of cross-cultural construct validity of the SRLE. Future use within other Western European societies is recommended.  相似文献   
43.
This study was designed to evaluate the toxicity of the aqueous extract of Aspilia africana leaves. Oral doses of 500 mg/kg and 1000 mg/kg were administered for 28 days to rats after every 2 days for sub-acute toxicity. For acute toxicity, 5 doses of 2, 4, 8, 12 and 16g/Kg body weight were investigated in mice. The control groups consisted of mice or rats administered with distilled water. The signs of toxicity fluctuated lightly from one mammal to another throughout the experiment. The liver, kidneys and heart weight of rats revealed no significant differences between the test groups and the control. The results indicated that the medium lethal dose (LD50) was found to be greater in females than males with an average of 6.6g/Kg body weight for both sexes. Regardless of the significant differences observed at certain points in some biochemical parameters (ALT, AST, ALP, Creatinine and Glutathione); none showed any linear dose responsiveness. On the other hand, most of the parameters investigated were found to be gender dependent. These results suggested that A Africana can be classified among substances with low toxicity.  相似文献   
44.
目的:目前,国内X(γ)刀的国家检定规程正在起草之中,本文的目的是为X(γ)刀剂量测量提供合理的设备与吸收剂量计算方法。材料与方法:利用德国PTW-UNIDOS剂量仅与有效体积为0.015cc的针尖电离室及自制的小体积半导体探测器相匹配,在160mm直径的有机玻璃球形模体内测量X(γ)刀的输出吸收剂量,并验证其治疗计划的实际输出剂量,得到较满意的结果。结论:为了保证剂量的准确度,X(γ)刀治疗计划系统的实际输出剂量应定期在现场测量与验证,所用探测器的直径应小于射野直径的1/2,小灵敏体积的半导体探测器适宜X(γ)刀小野(如:Ф4mm)的测量。  相似文献   
45.
Review of the mutagenicity of ethylene oxide   总被引:4,自引:0,他引:4  
Ethylene oxide has been shown to be an effective mutagen in a variety of organisms ranging from bacteria to mammalian cells. There is also an association between ethylene oxide exposure and human somatic cell cytogenetic damage. Furthermore, ethylene oxide has been shown to alkylate protein and DNA at exposure levels that have been encountered occupationally. Ethylene oxide is not only effective at producing somatic cell mutations but also at inducing genetic damage in germ cells. While it is clear that ethylene oxide is a germ cell mutagen in whole mammals, the mechanism(s) by which it produces genetic lesions in germ cells is uncertain.  相似文献   
46.
Evaluated the utility of neuropsychological testing in predictingacademic outcome in children 1 year following traumatic braininjury (TBI). Fifty-one schoolage children who were admittedto hospital after TBI were assessed with a battery of neuropsychologicalmeasures at 3 months postinjury. Academic achievement was assessedat 3 and 12 months postinjury. The neuropsychological batteryincluded intelligence testing and measures of memory, learning,and speed of information processing. Academic outcome was assessedin terms of post-TBI changes in reading, spelling, and arithmetic;changes in teacher ratings of school performance; and changein school placement. According to logistic regression analysis,change in placement from regular to special education at 1-yearpost-TBI was predicted by injury severity and by neuropsychologicalperformance at 3 months post-TBI. Findings suggest that neuropsychologicaltesting is useful in identifying children with special educationalneeds subsequent to TBI.  相似文献   
47.
Examined the utility of a new parent-report measure designedspecifically for pediatric inpatients, the Behavioral Upsetin Medical Patients-Revised (BUMP-R). The BUMP-R was administeredto 151 mothers of hospitalized children ages 4–12 yearsthe day following the child's hospital admission. The BUMP-Rdemonstrated good internal consistency and a factor analysisrevealed four factors identified as negativity/agitation, amiability,dysphoria, and noncom-pliance. Children exhibiting behavioraldistress at home were more likely to experience adjustment problemsupon hospitalization. Demographic and illness-related variableswere not substantial risk factors for hospital adjustment difficulties.  相似文献   
48.
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS.  相似文献   
49.
This retrospective study involved 463 breast cancer patients treated by radiotherapy alone at the Princess Margaret Hospital and at the Institut Gustave-Roussy. These patients either had operable tumors, but were unfit for general anesthesia, or had inoperable tumors due to local contraindications to surgery. Results were analyzed according to tumor response, local recurrence rate, tumor size, tumor fixation, nodal fixation and tumor dose. Conventional statistical analysis of local control showed two significant factors: tumor dose and tumor size. Multivariate analysis permitted to define an "individual risk" (IR) of local recurrence according to three independent factors: tumor size, tumor fixation, and nodal fixation. It was shown that the IR was a good prognostic factor for local control. Increase in tumor dose gave a similar effect in the local recurrence relative risk for all the IR groups. According to the slope of the dose-effect curve, it was deduced that a dose increase of 15 Gy can decrease the relative risk of local recurrence 2-fold. In fact, it was shown that tumor dose was the most significant independent factor on local control, able to produce up to a 10-fold increase compared to 2-fold decrease for tumor size. If the IR of local recurrence is known, a theoretical predictive value on local control, taking into account the tumor dose, can be determined according to the present data.  相似文献   
50.
Zusammenfassung Anhand einer prospektiven, auslesefreien Serie von 22 Patienten mit perforierten Ulcera im Gastroduodenalbereich verweisen wir auf die begrenzte diagnostische Aussagekraft einfacher anamnestischer, klinischer und radiologischer Daten. Lediglich bei acht Patienten (36%) ergaben sich wesentliche Indizien aus Krankengeschichte und Aufnahmebefund. Bei 16 Patienten (73%) verriet die Thoraxübersichtsaufnahme durch Nachweis einer subphrenischen Luftsichel eine Perforation im Magen-Darm-Trakt. Die Ultraschalluntersuchung wird als bedeutungsvolle Ergänzungsmethode vor allem in der diagnostischen Abklärung radiologisch negativer Ulcusperforationen vorgestellt und diskutiert. Dabei werden die sonographisch faßbare flüssigkeitsbedingte Magendistension sowie das Magenwandödem als unspezifische Kriterien gewertet. Der Objektivierung einer pathologischen Magenkokarde kommt bei gleichzeitigem Nachweis freier Luft und/oder extraluminärer Ingesta sowie freier echoloser Transsudatflüssigkeit pathognomonische Beweiskraft zu. Selbige Ultraschallkriterien erlaubten im einschlägigen Krankengut bei 16 Patienten (73%) eine definitive Diagnose und erfaßte 4 Patienten mit negativem Röntgen. Die kombinierte Analyse radiologischer und sonographischer Befunde führte somit bei 20 Patienten (91 %) unverzüglich zur korrekten Diagnose.
Perforated peptic ulcer: Diagnosis and assessment by sonography
Summary In a prospective unselected series of 22 patients with perforated gastroduodenal ulcers the diagnostic efficacy of clinical and radiologic data was modest. In eight patients only (36%), clinical data yielded sufficient evidence; in 16 patients (73%), plain X-ray demonstrated subphrenic gas. Sonography was proven to be a major advance, especially rewarding in the diagnosis of perforations with negative plain X-ray. Gastric distention and stomach wall edema are unspecifc sonographic criteria, whereas objectivation of a pathologic stomach cockade in the presence of free gas, extraluminary ingesta or echofree fluid in the peritoneal cavity are pathognomonic data. These criteria yielded a definite diagnosis in 16 patients (73%) including four patients with negative X-ray. The combined analysis of radiologic and sonographic findings yielded an immediate correct diagnosis in 20 patients (91%).
  相似文献   
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