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排序方式: 共有687条查询结果,搜索用时 15 毫秒
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32.
Franzon RC Montenegro MA Guimarães CA Guerreiro CA Cendes F Guerreiro MM 《Journal of child neurology》2004,19(6):418-423
This study describes the clinical, electroencephalographic, and behavioral features of 36 children with temporal lobe epilepsy. Patients were divided into two groups: group A, with 6 patients (< 6 years), and group B, with 30 patients (6-18 years). Statistical analysis was performed considering the significance level of .05. Regarding the clinical features of the focal seizures, motor components were more frequently seen in children younger than 6 years of age (P < .01), whereas automatisms were more frequently seen in patients older than 6 years of age (P < .05). Associated myoclonic seizures were more frequent in the younger age group (P < .01). Behavioral disorders such as hyperactivity and aggressiveness and speech delay were more common in the younger age group (P < .05). Temporal lobe epilepsy in children younger than 6 years of age is more frequently associated with motor components, myoclonic seizures, behavioral disorders, and speech delay. Conversely, temporal lobe epilepsy in older patients has frequent automatisms. 相似文献
33.
Searching for preeclampsia genes: the current position 总被引:12,自引:0,他引:12
Lachmeijer AM Dekker GA Pals G Aarnoudse JG ten Kate LP Arngrímsson R 《European journal of obstetrics, gynecology, and reproductive biology》2002,105(2):94-113
Although there is substantial evidence that preeclampsia has a genetic background, the complexity of the processes involved and the fact that preeclampsia is a maternal-fetal phenomenon does not make the search for the molecular basis of preeclampsia genes easy. It is possible that the single phenotype 'preeclampsia' in fact should be divided into different sub-groups on genetic or biochemical level. In the present review, the preeclampsia phenotype and its pathophysiologic features are discussed. Family studies and postulated inheritance models are summarized. A systematic overview is given on the numerous candidate gene studies and gene-expression studies performed so far and on the currently available genome-wide scan data. Despite extensive research the molecular genetic basis of preeclampsia remains unclear. Future studies will hopefully enhance our insights in the molecular pathogenesis of preeclampsia. 相似文献
34.
Pucci V Bugamelli F Mandrioli R Luppi B Raggi MA 《Journal of pharmaceutical and biomedical analysis》2003,30(5):1549-1559
Progesterone was determined in commercial pharmaceutical formulations and experimental micellar systems by means of two analytical methods based on liquid chromatography and derivative spectrophotometry. The chromatographic analysis, with ultraviolet detection at 245 nm, was carried out on a C8 column using a mobile phase composed of 2-propanol and a pH 2.5, 30 mM phosphate buffer. Derivative spectrophotometry (DS) used the difference between the values of the first derivative at 227.2 and 253.6 nm. Both methods require only a simple extraction procedure of progesterone from the formulations before analysis. The high-performance liquid chromatography (HPLC) procedure allows for the quantitative determination of progesterone in all pharmaceutical formulations tested (oily and alcoholic injectable solutions, gel preparations and soft capsules) and also of the newly-developed polymeric micellar system. On the contrary, the derivative spectrophotometric method is not suitable for the pharmaceutical formulation containing estradiol and for the new micellar systems. The results obtained with the two methods are in good agreement and always satisfactory in terms of precision and accuracy. 相似文献
35.
Ferreira MA Nunes Odel R Leal LK Pessoa OD Lemos TL Viana GS 《Biological & pharmaceutical bulletin》2003,26(5):595-599
In previous studies in vitro we showed that the quinone fraction (QF) from the heartwood of Auxemma oncocalyx TAUB. presented antiplatelet and antioxidant activities. In the present work, the QF antioxidant property was evaluated in models of CCl(4)-induced hepatotoxicity in rats, and prolongation of pentobarbital-induced sleeping time in mice. Our results showed that levels of plasma glutamate-pyruvate-transaminase (GPT), as well as glutamate-oxalate-transaminase (GOT), were increased by the administration of CCl(4). On the other hand, only GPT levels were reduced by the QF treatment. Pentobarbital sleeping time was prolonged by the administration of CCl(4) and reduced by the QF treatment. Moreover, QF did not alter the pentobarbital-induced sleeping time. In conclusion, we showed that QF, represented mainly by oncocalyxone A, has hepatoprotective activity, and this effect is at least in part due to the antioxidant activity of this quinone. 相似文献
36.
Bisacchi D Benelli R Vanzetto C Ferrari N Tosetti F Albini A 《Cancer Detection and Prevention》2003,27(3):229-238
The recognition that angiogenesis is a key early event in tumor progression and metastasis has led to the development of new strategies for cancer therapy. The generation of a new blood vessel network under physiological conditions is regulated by the concerted action of activators and inhibitors. Perturbation of this balance, as it occurs in solid tumor growth and metastasis, appears to be a critical point in tumorigenesis. This has led to the "angiogenic switch" hypothesis: the point at which a tumor acquires the potential to induce angiogenesis is a critical step towards malignancy. Based on experimental evidence, prevention of blood vessel development appears to be the mechanism of action of many successful chemopreventive drugs of natural or synthetic origin: a novel concept that we termed "angioprevention". The hypothesis that anti-angiogenesis is at the basis of tumor prevention also suggests that many anti-angiogenic drugs could be used for chemoprevention in higher risk populations or in early intervention. There is a growing body of experimental evidence that anti-angiogenic strategies will contribute to the future therapy of cancer, several compounds with anti-angiogenic properties are now under clinical investigation including anti-inflammatory compounds, as inflammation may play a key role in angiogenesis. We must persevere in the development of novel, powerful and safer angiogenesis inhibitors and in the use of anti-angiogenic drugs in combination with other natural or synthetic anti-cancer agents in a biological therapy strategy. 相似文献
37.
Dermatoscopy improves the sensitivity and the specificity in the diagnosis of melanoma. Although the reproducibility of dermatoscopic features has been the subject of research, no study up to now has compared the reproducibility of dermatoscopic features to the reproducibility of the clinical criteria of the ABCDE rule. For this reason we decided to examine the reproducibility of the clinical ABCDE rule and of our diagnostic dermatoscopic method 7FFM, as well as of the individual criteria of both. A total of 73 dermatologists attended three dermatoscopic courses and examined a set of clinical and dermatoscopic slides of 50 pigmented skin tumors. Agreement % and K value for a kappa statistical analysis have been calculated to evaluate inter-rater reliability. The clinical and the dermatoscopic methods showed similar values of concordance: clinical score 2 mean agreement = 68%, mean K = 0.44; clinical score 3 mean agreement = 73%, mean K = 0.61; 7FFM mean agreement = 83%, mean K = 0.64. The clinical criteria A, B, and C and the dermatoscopic features of our method presented similar values of concordance as well: clinical criteria mean K range 0.35-0.25, dermatoscopic features mean K range 0.62-0.25. The dermatoscopic features of our method 7FFM show a good reproducibility after a short training program, similar to the reproducibility of the clinical criteria of the ABCDE rule for the diagnosis of melanoma. 相似文献
38.
Guido Bocci Romano Danesi Umberto Benelli Federico Innocenti Antonello Di Paolo Stefano Fogli Mario Del Tacca 《Cancer chemotherapy and pharmacology》1999,43(3):205-212
The aim of the present study was to test the ability of the chemotherapeutic agent suramin to inhibit angiogenesis in experimental
models in vitro and in vivo. In the culture of rat aortic rings on fibronectin, suramin dose-dependently inhibited vascular
cell growth, achieving the maximal effect (mean − 88% versus controls, P < 0.05) at 400 μg/ml. Image analysis showed that suramin could inhibit microvessel sprouting in fibrin from rat aortic rings
as evaluated by the ratio between the cellular area and the mean gray value of the sample (sprouting index); suramin at 50 μg/ml
significantly reduced the sprouting index from the control value of 0.35 ± 0.04 to 0.14 ± 0.02 mm2/gray level (P < 0.05). Likewise, the area occupied by cells was 19.2 ± 1.8 mm2 as compared with 41.8 ± 4.2 mm2 in controls (P < 0.05). In the rat model of neovascularization induced in the cornea by chemical injury, suramin at 1.6 mg/eye per day reduced
the length of blood vessels (0.7 ± 0.1 mm as compared with 1.5 ± 0.1 mm in controls, P < 0.05). In the same model the ratio between the area of blood vessels and the total area of the cornea (area fraction score)
was decreased by suramin from 0.19 ± 0.02 in controls to 0.03 ± 0.003 (P < 0.05). Suramin given i.p. at 30 mg/kg per day markedly inhibited the neovascularization induced in the rat mesentery by
compound 48/80 or conditioned medium from cells secreting the angiogenic protein fibroblast growth factor-3 (FGF-3). The area
fraction score in control rats treated with compound 48/80 was 0.31 ± 0.03, and this was reduced to 0.07 ± 0.01 by suramin
(P < 0.05). After i.p. administration of FGF-3 the area fraction score was reduced by suramin from 0.29 ± 0.03 to 0.05 ± 0.01
(P < 0.05). These results provide evidence that suramin exerts inhibitory effects on angiogenesis in both in vitro and in vivo
models.
Received: 9 January 1998 / Accepted: 29 June 1998 相似文献
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