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61.
Medical monitoring systems are useful aids assisting physicians in keeping patients under constant surveillance; however, taking sound decision by the systems is a physician concern. As a result, verification of the systems behavior in monitoring patients is a matter of significant. The patient monitoring is undertaken by software in modern medical systems; so, software verification of modern medial systems have been noticed. Such verification can be achieved by the Formal Languages having mathematical foundations. Among others, the Z language is a suitable formal language has been used to formal verification of systems. This study aims to present a constructive method to verify a representative sample of a medical system by which the system is visually specified and formally verified against patient constraints stated in Z Language. Exploiting our past experience in formal modeling Continuous Infusion Insulin Pump (CIIP), we think of the CIIP system as a representative sample of medical systems in proposing our present study. The system is responsible for monitoring diabetic’s blood sugar. 相似文献
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64.
Morteza Mahdizadeh Masoumeh Masoumpour Hossein Ashraf 《Acta ophthalmologica. Supplement》2008,86(3):297-301
Purpose: To compare the anatomical results of scleral buckling with and without retinopexy and to assess the effect of retinopexy on the scleral buckling outcome. Methods: This randomized clinical trial was performed on 55 patients. Twenty‐two eyes were treated with scleral buckling (segmental or encircling) with or without drainage of subretinal fluid without any type of retinopexy (group 1); 33 patients received transscleral retinal cryopexy around retinal break(s) in addition to the former procedure. The two groups were matched regarding age, sex, myopia, aphakia, stage of proliferative vitroretinopathy (PVR) and number, type and location of the break(s). Results: In the non‐retinopexy group, 19 patients (86%) had complete retinal reattachment and one patient had partial reattachment after 34–48 months of follow‐up. One patient did not develop attachment because of missed break out of the buckle, and one had no attachment at all because of PVR. Overall success rate was 91% (20 of 22) in this group. In the retinal cryopexy group, 26 patients (79%) had complete retinal reattachment and two had partial reattachment during 35–56 months of follow‐up. In two patients, no attachment was achieved because of missed break out of the buckle; three patients developed redetachment after 1 and 3 months because of PVR. Overall success rate was 85% (28 of 33). The anatomical results in these two groups were the same statistically. Conclusion: With the permanent scleral buckling technique, retinal cryopexy adds no benefit to the success rate of anatomical retinal reattachment. 相似文献
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66.
Effectiveness and residual activity tests of granular formulations of 2 insect growth regulators (IGRs), s-methoprene and pyriproxyfen, against laboratory-reared larvae of 5 colonized mosquitoes, Aedes aegypti, Aedes albopictus, Aedes taeniorhynchus, Anopheles quadrimaculatus, and Culex nigripalpus, were conducted in the laboratory and outdoors in plastic tubs. Culex quinquefasciatus was exposed to these two IGRs in the laboratory only. Each IGR formulation was applied at 0.02 and 0.05 ppm active ingredient (Al) against 5 of the 6 mosquito species both in the laboratory and the outdoor evaluations, whereas Cx. quinquefasciatus was exposed to 0.2 and 0.4 ppm AI of s-methoprene, and 0.1 and 0.2 ppm AI of pyriproxyfen in the laboratory. s-Methoprene at 0.02 and 0.05 ppm AI resulted in variable levels (<39-100%) of inhibition of adult emergence in the 5 species monitored for 6 weeks after treatment under both test conditions. Aedes taeniorhynchus was the most susceptible to s-methoprene in terms of initial and residual activity. Culex quinquefasciatus and Ae. albopictus were the most tolerant to s-methopene, with maximum emergence inhibitions amounting to 84% in Cx. quinquefasciatus at 0.4 ppm and 44.3% in Ae. albopictus at 0.05 ppm during the 1st week in the laboratory. Pyriproxyfen at comparable treatment rates to s-methoprene caused very high levels (>80-100% in most cases) of initial and residual emergence inhibitions of the tested species in the laboratory as well as outdoors. In several species, pyriproxyfen induced complete inhibition of adult emergence for several weeks after treatment, even at the lower rate of 0.02 ppm. The World Health Organization has recently recommended the use of pyriproxyfen for the control of some mosquito species at specified rates in certain habitats. 相似文献
67.
Boshtam M Rafiei M Sadeghi K Sarraf-Zadegan N 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2002,72(5):309-314
This triple-blind placebo-controlled clinical trial was performed to determine the effects of the anti-oxidant vitamin E on blood pressure and heart rate in patients with mild hypertension. A total of 70 new mild hypertensive subjects (systolic blood pressure, SBP: 140-160 mmHg; diastolic blood pressure, DBP: 90-100 mmHg) without secondary hypertension were selected from among people referred to the Hypertension Unit of Isfahan Cardiovascular Research Center and divided randomly into two groups of drug (DG) and placebo (PG). All subjects were aged from 20 to 60 years old, without any other cardiovascular risk factors. The drug group received vitamin E tablets (200 IU/day) and the placebo group received placebo only for 27 weeks. At the beginning and the end of the study, the blood vitamin E level was measured fluorimetrically in all subjects according to the Hansen and Warwick method [14, 15]. Blood pressure and heart rate were measured at the beginning, during, and at the end of the study. Blood pressure was measured by a physician using one random zero mercury sphygmomanometer. Personal information and dietary habits of subjects were collected by separate questionnaire. At the end of the study, it was found that the vitamin E supplement had caused a remarkable decrease in SBP (-24% in DG versus -1.6% in PG) and a less remarkable decrease in DBP (-12.5% in DG versus -6.2% in PG) (p < 0.05). The change in heart rate was -4.3% in DG, and -14.0% in PG (p < 0.05). It is concluded that a vitamin E supplement of 200 IU/day can be effective in mild hypertensive patients in the long term, probably due to nitric oxide, and improve their blood pressure status. Therefore, vitamin E supplement could be recommended to such patients. 相似文献
68.
Javad Nasrollahzadeh Fereydoun Siassi Mahmood Doosti Mohammad Reza Eshraghian Fazel Shokri Mohammad Hossein Modarressi Javad Mohammadi-Asl Khosro Abdi Arash Nikmanesh Seyed Morteza Karimian 《Lipids in health and disease》2008,7(1):45
Background
Experimental studies indicate that gamma linolenic acid (GLA) and docosahexaenoic acid (DHA) may inhibit glioma cells growth but effects of oral consumption of these fatty acids on brain tumor fatty acid composition have not been determined in vivo. 相似文献69.
In this study, the effect of l-dopa and bromocriptine on morphine withdrawal syndrome was compared. Both l-dopa (125, 250 mg/kg, i.p.) and low doses of bromocriptine (0.04, 0.08 mg/kg, i.p.) potentiated naloxone-induced morphine withdrawal symptoms such as jumping, climbing and rearing in mice. Higher doses of bromocriptine (0.16, 0.32 mg/kg, i.p.) attenuated these naloxone-induced symptoms. SKF 83566, D(1) dopamine antagonist (0.4, 0.8 mg/kg, i.p.) and sulpiride, D(2) dopamine antagonist (5, 10 mg/kg, i.p.) when used alone, also produced inhibitory effects on naloxone-induced morphine withdrawal symptoms. Pretreatment with sulpiride (5, 10 mg/kg, i.p.) and SKF 83566 (0.4, 0.8 mg/kg, i.p.) attenuated the potentiating effects of l-dopa on withdrawal symptoms significantly. Pretreatment with sulpiride also decreased the potentiating effect of bromocriptine and reinforced the inhibitory action of it, but SKF 83566 pretreatment just reinforced the effect of higher doses of bromocriptine. Concurrent pretreatment of animals with sulpiride (10 mg/kg, i.p.) and SKF 83566 (0.8 mg/kg, i.p.) markedly decreased the potentiating effects of l-dopa and bromocriptine and reinforced the inhibitory action of bromocriptine on the naloxone-induced morphine withdrawal syndrome. Prazosin, alpha(1) antagonist (1, 2 mg/kg, i.p.) decreased the naloxone-induced morphine withdrawal syndrome significantly. Pretreatment with yohimbine, alpha(2)-antagonist (5 mg/kg, i.p.) reversed the inhibitory effects of bromocriptine (0.16, 0.32 mg/kg, i.p.) on naloxone-induced morphine withdrawal syndrome significantly. In conclusion, our results show that bromocriptine at lower doses (0.04, 0.08 mg/kg, i.p.) acts similar to l-dopa, but at higher doses (0.16, 0.32 mg/kg, i.p.) shows different effects on naloxone-induced morphine withdrawal syndrome which may be due to the interaction of bromocriptine with alpha-adrenoceptors. Copyright 2000 John Wiley & Sons, Ltd. 相似文献
70.
Behjati F Atri M Najmabadi H Nouri K Zamani M Mehdipour P 《Pathology oncology research : POR》2005,11(3):157-163
Breast cancer is amongst the leading causes of death in women worldwide and the most common cancer amongst Iranian women.
Unfortunately, the current clinical and histological criteria can only help 60 percent of women with breast cancer in diagnosis
and long-term treatment. Therefore, genetic markers both at single gene and chromosomal level can play an important role in
improving the diagnosis and prognosis of breast cancer patients. The aim of this retrospective study was to investigate the
role of chromosome 1 and 8 copy number assessed by interphase fluorescence in situ hybridization (FISH), as prognostic parameters
in 50 Iranian women, aged 35 to 64 years, with sporadic invasive ductal breast carcinoma. Chromosome 1 and 8 copy numbers
were evaluated in relation to established clinicopathological parameters, the immunohistochemical markers ER, PR, P53 and
cathepsin D, DNA index by flow cytometry, age and survival status of the patients. FISH using centromeric probes for chromosomes
1 and 8 was applied to interphase cell suspensions prepared from archived, Carnoyfixed tumor cells and selected paraffin-embedded
tumor sections. Aneusomy for chromosomes 1 and 8 was present in all 50 patients to different levels. The total abnormality
rate for chromosome 1 was 33.92 percent (4.24 percent monosomy and 29.68 percent polysomy), whereas for chromosome 8 this
rate was 28.30 percent (6.48 percent monosomy and 21.82 percent polysomy). Statistically significant association (p<0.05)
was demonstrated between monosomy 1 and patients’ age below 50 years, and between monosomy 1 and poor survival, respectively.
Disomy 8 was significantly associated with P53 expression. A borderline significant correlation was demonstrated between polysomy
8 and diploid DNA content, as well as between disomy 1 and disease-free status of the patients. Chromosome 1 and 8 copy numbers
may be considered as useful prognostic markers in invasive ductal carcinoma of the breast. 相似文献