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21.
This work describes the synthesis of new amphiphilic perfluorohexyl- and perfluorooctyl-propanethio-beta-cyclodextrins and the comparison of the ability of these molecules and alkyl analogue, nonanethio-beta-cyclodextrin to form nanospheres. Nanospheres were prepared using nanoprecipitation method (perfluoroalkylthio-beta-cyclodextrin in THF [0.11 x 10(-3)M], stirring rate 700rpm, addition of aqueous phase at 64 degrees C into organic phase at 50 degrees C). They were characterised by Photon Correlation Spectroscopy (PCS) and by electron microscopy (SEM and cryo-TEM). The nanospheres prepared from these new beta-cyclodextrin derivatives have an average size of 260nm, and appear to be spherical in cryo-TEM images. Whereas alkyl analogue forms polydisperse aggregates with sizes in the range 60-350nm.  相似文献   
22.
Misuse of zopiclone and convulsions during withdrawal.   总被引:3,自引:0,他引:3  
It has been documented that benzodiazepines have the potential to cause dependence and withdrawal reactions, including convulsions. However, the available data concerning zopiclone, a nonbenzodiazepine hypnotic, are insufficient. The present study describes the case of a 36-year-old man who repeatedly misused zopiclone, in daily doses of 60-90 mg. Furthermore, the patient suffered from convulsion on two occasions following abrupt withdrawal of zopiclone. The concomitant use of alcohol, trimipramine, and promazine may have contributed to the development of convulsions. It is concluded that zopiclone may cause problems associated with misuse and withdrawal reactions similar to those of benzodiazepines.  相似文献   
23.
J Gaál  Z Sziray  G Papp  M Gávai 《Orvosi hetilap》1989,130(9):447-452
The incidence over 10% of premature delivery in Hungary was studied. The cause which motivated this work was the fact that despite of several preventive and therapeutic measures the incidence e.g. in BAZ county surpassed even the average of the country. Professors of clinics in different countries of Europe as well as medical societies dealing with this question have been consulted about the matter of whether it was sufficient to consider a neonate a premature infant and the delivery a premature one solely on the basis of birth weight (under 2.500 g). Data of BAZ county proved that this determination was misleading and proposals are made concerning the modification on the basis of the examinations of the authors.  相似文献   
24.
We describe an unusual case of absolute bilateral phakolytic glaucoma. On admission for cataract surgery the 75-year-old patient was found to be totally blind, no light perception in either eye. The ocular tensions were about 75 mmHg in both eyes, corneas hazy, the fundi could not be seen. The swollen lens of the right eye had slightly subluxated downwards. In the left eye the ultrasound showed a luxated swollen lens in the vitreous space. The ultrasound also revealed totally excavated optic discs. This patient had been on the waiting list for 8 months. Information of the stage of the cataracts of patients on the waiting lists for operation is of paramount importance in the prevention of lens induced problems which may lead to irreversible visual deterioration.  相似文献   
25.
26.
BACKGROUND: Many interrelationships exist between the thyroid gland and the gastrointestinal tract. Several past and recent studies have shown that the thyroid gland profoundly influences the structure and function of the exocrine pancreas in the rat. In the present study we investigated the effect of methimazole (METZ), an antithyroid drug, on cerulein induced acute pancreatitis (AP) in rats. METHODS: Rats were divided into 3 groups (10-12 weeks age, 200-250 g weight, n: 10). Group B was made hypothyroid with methimazole 5 mg/kg daily for 10 days and the others were untreated euthyroid groups. After 10 days, acute pancreatitis was induced with four doses of 20 microg/kg body weight of cerulein administered s.c at hourly intervals in group A and B while the control group C was given 4 doses of I ml saline. Pancreas wet weight (mg), plasma amylase activity (IU/l) and pancreatic histology were used as endpoints to quantify the severity of the AP. RESULTS: Plasma tri-iodothyronine (T3) (ng/dl) and thyroxine (T4) (microg/dl) levels were significantly reduced after METZ treatment for 10 days (p < 0.01). METZ pretreatment reduced significantly the cerulein induced increase in pancreatic weight (1,205 +/- 12 mg in METZ treated AP group versus 1,617 +/- 14 mg in AP group, p < 0.05) and the rise in amylase activity (7,078 +/- 816 IU/l in METZ treated AP group versus 8,611 +/- 830 IU/l in AP group p < 0.05). CONCLUSION: METZ reduces the severity of cerulein induced AP in rats. This effect might be through its antithyroid property.  相似文献   
27.
The authors measure the efficacy of three methods for predicting the time to infection for susceptible individuals in a population undergoing an HIV epidemic. The methods differ in whether they require detailed information of the contact network and whether they require knowledge of the initial source of infection. Efficacy is evaluated using simulations for 20 different contact patterns. Only the risk score that uses both kinds of information accounts for more than 15 per cent of individual variability. The efficacy of this score ranges from 10 per cent in very unstructured populations to 60 per cent for spatially localized contact networks. This improved performance may be explained by the larger fraction of the total variability not due to the disease dynamics. When all variables are dichotomized, the two poorer methods produce odds ratios between 1.4 and 2.3. The odds ratio for the risk score with full information ranges from 2.5 to 17. Risk assessment protocols and intervention programmes are encouraged to assess contact patterns and detect sources of infection.  相似文献   
28.
Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures. The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral vascular disease.  相似文献   
29.
The aim of this experimental ultrasound study on six fetal lambs was to evaluate how blood flow variables and vessel diameters of the descending aorta and the common carotid artery change during fetal asphyxia in the acute preparation. When acute asphyxia was induced by obstructing the maternal aortic blood flow all fetuses reacted with significant decrease in the aortic diameter and blood flow. In the common carotid artery vessel diameter and the blood flow increased significantly. The results support the theory of a brain sparing effect during fetal distress with significant changes of blood vessel diameters occurring in opposite directions in the aorta and the common carotid artery, thereby contributing to the centralisation of circulation.  相似文献   
30.
The work situation of 66 male patients who underwent elective coronary artery bypass surgery (CABS) and who had been randomly allocated to receive cardiac rehabilitation (group R) was compared with the work situation of 59 similar patients allocated to receive only standard care (group H). The follow-up time was one year. The proportions of subjects working in groups R and H were 26% and 20% (p=ns) before the CABS, 45% and 34% (p=ns) 6 months and 56% and 38% (p=ns) 12 months after the CABS, repectively. The increase in proportion of subjects who worked was significant in both groups at both 6 and 12 months after the CABS (p<0.05 for all changes). The increases were not significantly different between the whole groups, but in patients younger than 55 years of age, return to work was more frequent in group R than in group H (at 12 months 60% vs. 35%, p for the difference in change=0.02). Stepwise logistic regression analysis of the factors influencing return to work showed that a patient's judgement of his own working capacity as good 6 months after CABS (odds ratio (OR) 8.5, confidence interval (CI) 2.3–32.0), functional class 16 months after the CABS (OR 6.7, CI 1.8–24.5), his desire to work (OR 6.4, CI 1.6–26.0) and absence from work of less than 3 months before the CABS (OR 4.9, CI 1.2–20.2) were significant positive predictors of return to work 1 year after the CABS.  相似文献   
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