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71.
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   
72.
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   
73.
A retrospective multicentre study of 341 children with persistent/recurrent, isolated haematuria is described. The haematuria was isolated for at least 6 months at the beginning of observation. The duration of follow-up was 2–5 years in 201, 5–10 years in 119, 10–15 years in 19, and over 15 years in 2 cases. Of these patients 47.8% became symptom-free. In 18.4% the haematuria remained isolated; in 13.8% it was combined with proteinuria over 250 mg/day more than 2 years later. The occurrence of associated proteinuria increased progressively with time. It was 8.6% between the 3rd and 5th years, and 37.0% after the 5th year. Renal biopsy was performed because of the symptoms of glomerular disease in 47 cases at an average time of 12 months following the appearance of proteinuria. Proteinuria appeared after a 2–5, 5–10, 10–15 and more than 15 years follow-up period in 16, 23, 6, and 2 patients respectively; 14 of them had Alport's nephropathy. The percentage of more serious azotaemia was 1.7 (creatinine clearance: 10–50 ml/min per 1.73 m2) and 0.3 (creatinine clearance: < 10 ml/min per 1.73 m2). Mortality was 0.58%. Most of the patients who developed severe azotaemia had persistent microscopic haematuria at the beginning. The prevalence of hypertension was only 1.2%. The time of its appearance was above 5 years in 2 and below 5 years in 2 cases. All these patients had chronic glomerulonephritis. The haematuria was associated with hypercalciuria in 19.9%. In 14.3% of the overall group of patients urolithiasis developed 2–15 years after onset. All of these had hypercalciuria. Our findings suggest that symptoms of isolated haematuria may last for a longterm period and need systematic control. When proteinuria and/or hypertension is associated with haematuria a worse prognosis can be expected.Participating paediatric hospitals and university departments: Second Department of Paediatrics, I. Semmelweis Medical University of Budapest (M. Visy); Department of Paediatrics, University Medical School of Pécs (V. Jászai); Department of Paediatrics, A. Szent-Györgyi Medical University of Szeged (I. Haszon, S. Túri); County Children's Hospital, Miskolc (Á. Vissy); P. Heim Children's Hospital, Budapest (Z. Czirbesz); County Children's Hospital, Györ (Zs. Szelid); Buda-Children's Hospital, Budapest (I. Ferkis); I. Apáthy Hospital, Budapest (J. Kisbán); János Hospital, Budapest (I. Marosváry); Hospital of Hungarian State Railway, Budapest (J. Fehér); L. Madarász Hospital, Budapest (F. Kalmár); South Pest Hospital, Budapest (G. Halász); County Children's Hospital, Pécs (E. Kolman); County Children's Hospital, Gyula (P. Sipos); County Children's Hospital, Szolnok (I. Jaksics); County Children's Hospital, Debrecen (Á. Miskolczi); County Children's Hospital, Tatabánya (I. Kiss); County Children's Hospital, Eger (M. Frank, E. Ladányi); County Children's Hospital, Nyíregyháza (E. Bujdosó); County Children's Hospital, Szombathely (M. Andics); Kerepestarcsa Hospital, Budapest (M. Marcell); Komárom Hospital, Komárom (J. Kecskés)  相似文献   
74.
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   
75.
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   
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78.
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   
79.
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   
80.
Acute toxicity of ammonia to Artemia sp.]   总被引:1,自引:0,他引:1  
The acute toxicity of total ammonia-N, (NH3 + NH4+), and un-ionized ammonia-N, NH3-N, on newly hatched Artemia nauplii and Artemia adults was measured in 24, 48, 72, and 96-h semi-static bioassays system. There was a significant difference (P < 0.05) in medial lethal concentrations (LC50) obtained during the tests. The LC50 values on nauplii ranged from 650 mg/l, in 24-h, to 399.1 mg/l total ammonia-N, in 96-h, while the LC50 values on adults ranged from 1290.4 mg/l to 600.5 mg/l total ammonia-N, in the same period. Two methods for calculations of un-ionized ammonia toxicity are analyzed and discussed.  相似文献   
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