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21.
With regard to adaptation of green ash (Fraxinus pennsylvanica Marshall) to ecological conditions in Croatia, pollen germination and pollen tube length after 2, 4 and 6 hours were examined in vitro at 10, 15, 20 and 25°C during two years 2001 and 2002. Narrow leaved ash (F. angustifolia Vahl) pollen served as a control in 2002. The year, time and temperature, and the interaction between time and temperature were significant for both germination percentage and pollen tube length. Interactions year × temperature and year × time were significant for pollen tube length only. The highest germination percentage (17.86% in 2001 and 19.40% in 2002) of green ash pollen was at 15°C after 6 hours. The pollen tube length was greatest at 20°C (393.46 μm) in 2001 and 25°C (899.50 μm) in 2002 after 6 hours. Narrow leaved ash pollen had the highest germination percentage (19.22%) at 20°C after 6 hours and was significantly reduced at 25°C. The pollen tube length was greatest at 25°C (518.90 μm) after 6 hours. It can be concluded that green ash pollen has satisfactory germination in ecological conditions in Croatia and that the optimum temperature for pollen germination is higher than 20°C.  相似文献   
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Neurofibromatosis type 1 (NF 1) is an autosomal dominant disorder with high index of spontaneous mutations and extremely varied and impredictible clinical manifestations. The aim of this work was to give an account of eye disorders in NF1. 132 patients of age 0-16 years with NF1 were followed up for 15 years. They were checked repeatedly for ophthalmologic disorders. Frequent eye disorders were: Lisch nodules (Iris hamartomas, IH) 78%, hyperthelorism 19.7%, bulbomotoric disorders 15.9%, disorders of the optic disc 16.7% and optic gliomas (18.9%). The highest incidence of eye disorders by NF1 patients showed Lisch nodules (IH). Its ease of clinical recognition and if present with other diagnostic signs (for instance café au lait patches) could be deemed as reliable diagnostic criterion of NF1 in childhood.  相似文献   
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This study was undertaken to evaluate the effect of galanthamine, a new cholinesterase inhibitor on cognitive performances in 84 patients with various apoE genotype and Alzheimer's disease (AD) during the six-month treatment. The diagnosis of AD was made on the basis of NINCDS/ADRDN criteria. ApoE4 genotype was determined by PCR procedure. The cognitive performance was assessed MMSE at baseline and six months later. The difference among the groups was statistically analyzed by ANOVA model and Pearson's chi2-test. The MMSE at baseline in all completes was 18.0 +/- 3.73, whereas the mean value of MMSE after 6 months was 16.4 +/- 5.61 indicating significant deterioration (p < 0.01). Of the 84 patients, 14 (169%) were apoE4 homozygous, 41 (49%) were heterozygous, whereas 29 (35%) were apoE4 negative. The significant number of responders was observed among apoE4 homozygous patients (71%; chi2 = 6.89; p = 0.032). The subgroup of apoE4 homozygous patients with AD in its mild to moderate stage may be considered as responders to galanthamine.  相似文献   
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Talocrural joint injuries are among the most common injuries of the joints and therefore there is a need for a holistic approach to analysis of morphology, biomechanics and visualization of the talocrural joint ligamentary apparatus in different positions. The research was carried out on 20 fresh and conserved anatomical specimens of the lower leg on which X-ray, computed tomography, ultrasonography and stress analysis were performed before and after the lesion of ligaments. Also the gait of 130 adults without (100) and with ligament and joint capsule lesion (30) was analyzed by infrared telemetry. After complete discission of the lateral ligaments, arthrography and CT could register the lesion, while X-ray and ultrasonography could not detect it. Gait analysis of healthy and injured leg showed that the injured leg was significantly less loaded.  相似文献   
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Macroevolutionary trends traditionally are studied by fossil analysis, comparative morphology or evo-devo approaches. With the availability of genome sequences and associated data from an increasing diversity of taxa, it is now possible to add an additional level of analysis: genomic phylostratigraphy. As an example of this approach, we use a phylogenetic framework and embryo expression data from Drosophila to show that grouping genes by their phylogenetic origin can uncover footprints of important adaptive events in evolution.  相似文献   
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Insulin resistance has been documented in type 1 diabetes and may contribute to the high risk for cardiovascular disease in this population and progression of nephropathy. We investigated associations of renal parameters, including urinary albumin excretion rate (UAE), serum creatinine and creatinine clearance, with surrogate measure of insulin sensitivity calculated using a formula derived from euglycemic-hyperinsulinemic clamp studies (estimated glucose disposal rate, eGDR). Study included 353 patients with type 1 diabetes, none showed signs of adrenal, thyroid, renal, or cardiovascular diseases. Insulin sensitivity was measured with eGDR calculated with the equation: 24.31-(12.22xWHR)-(3.29xHT)-(0.57xHbA1c). The units were mgkg(-1)min(-1); WHR=waist to hip ratio; HT=hypertension. Correlations and logistic regression analysis were performed to identify relationships between renal parameters and eGDR, individual components of insulin resistance and risk of insulin resistance. UAE and serum creatinine significantly correlated with insulin resistance measured by eGDR (r=-0.13, and -0.17, all p<0.05), and its components disorders, WHR and HbA1c. After stratifying patients in quartiles of eGDR, those in the upper quartile of the eGDR had significantly reduced levels of UAE and serum creatinine, compared to subjects in lowest quartile. In a logistic regression analysis risk for development of insulin resistance in our subjects were independently predicted only by UAE (odds ratio = 1.01, p<0.01). Our results provide evidence of associations between insulin resistance and its components disorders with renal parameters, such as UAE and serum creatinine. Insulin resistance, measured with eGDR, predicts the increment in UAE in subjects with type 1 diabetes. Since progression to microalbuminuria is likely to occur in majority of diabetic patients, there is a need to further explore the role of risk factors such as insulin resistance.  相似文献   
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The structure of teeth in all living beings is genetically predetermined, although it can change under external physiological and pathological factors. The author's hypothesis was to indicate evolutional shifts resulting from genetic, functional and other differences. A comparative study about certain characteristics of incisors in humans and myomorpha, the fat dormouse (Glis glis) being their representative as well, comprised measurements of enamel and dentin thickness in individual incisor segments, evaluation of external enamel index, and also assessment of histological structure of enamel and dentin. The study results involving dormice showed the enamel to be thicker in lower than in the upper teeth, quite contrary to enamel thickness in humans. In the upper incisors in dormice the enamel is the thickest in the medial layer of the crown, and in the cervical portion of the crown in the lower incisors. The thickness of dentin in dormice is greater in the oral than in the vestibular side. These findings significantly differ from those reported in reference literature, but they are based on the function of teeth in dormice. Histological characteristics of hard dental tissues in dormice are similar to those in humans, with exception of uniserial structure of enamel and appearance of dentinoenamel junction.  相似文献   
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