مجله زیست شناسی ایران
سال بیست و سوم شماره 3 (امرداد و شهریور 1389)

Variation in vegetation of forest gaps predominant by several factors. Unerring، the role of physiographic factors within gaps biodiversity process is very considerable. Hence، the relation of vegetation with physiographic positions was investigated within 59 forest gaps in Fagus forests of Lalis located in Chalous. Elevation range classified in three classes (1100-1200، 1200-1300، and 1300-1400) and slope in five classes (%0-20، %20-40، %40-60، %60-80، %80-100)، also. Aspects quantified by Azimuth، and plant species abundance annotated within gaps. Determination of relation between biodiversity indices and physiographic factors were accomplished by correlation coefficients. Results showed that، differences in mean quantities of biodiversity were significant for increasing of elevation. In survey of slope classes، differences in mean quantities of Simpson، Margalef and Peet indices a strong negatively correlation for the increase of slope، but other indices lacked significant correlation. Also in survey of aspects with differences in mean quantities of Shannon-Wiener، Menhinick، Peet and Camargo indices were significant correlation، and totality northern aspects devoted in most of biodiversity indices quantities.

Cardiovascular diseases and atherosclerosis are the leading cause of mortality and morbidity around the world. Inflammation and coagulation are two important risk factors of Cardiovascular disease. In this study, the effect of hydroalcoholic extract of Hypericum perforatum on inflammatory and coagulation factors in hypercholesterolemic rabbits was studied and its effect was compared with lovastatin. 25 adult male Newzeland rabbits were randomly divided into five groups of five and were fed for 60 days as follows: basic diet, high cholesterol, basic diet along with Hypericum extract (150mg/kg), high cholesterol along with Hypericum extract (150mg/kg) and high cholesterol along with lovastatin (10mg/kg). Blood samples were taken at the beginning, one month later and at the end of the study in order to measure their serum factors. The result showed that both the extract and lovastatin reduced significantly C-reactive protein (CRP), white blood cell(WBC), fibrinogen and platelet compared with high cholesterol group. Therefore Hypericum by decreasing inflammation and coagulation risk factor cause prevention of atherosclerosis also results showed that the extract in more effective to decrease cardiovascular risk factor than lovastatin.

The urohyal bone is a single median solid bone with anterior tip generally connected to the ventral hypohyal and to the first basibranchial and the posterior end attached to the pectoral girdle by means of muscle. This bone has been generally used for age determination، but recently it has been distinguished that its morphology is diverse in different groups of fishes such that could be used in fish taxonomy. In the present study، the morphology of urohyal in 19 species fishes from 17 genera، 6 families and 5 orders of Caspian Sea basin has been studied. Results showed that the urohyals were varied in ventral، dorsal and lateral shape، presence and number of process in the anterior part، origin of dorsal keel (distance from anterior tip)، groove in ventral portion and some other attributes. In studied cyprinid fish، the ventral part of the urohyal forms a triangular facet، which may be with or without groove. All the members of Leuciscinae have the same urohyal with two-branched anterior part. But in Cyprininae، it is not two-branched. Base on the morphology of urohyal in different groups of studied fish، it seems that Acheilognathinae، Squalliobarbinae and Leuciscinae are close to each other that the other subfamilies. In Gobiidae and Esocidae، the urohyal lack ventral sides or it is reduced. Based on the urohyal bone morphology we prepared a pictorial key for identification of some fishes of Caspian Sea basin for the first time.