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91.
Seven 9,10-seco-9,19-cyclolanostane arabinosides, named podocarpasides A-G (1-7), were isolated from the roots of Actaea podocarpa DC., a species closely related to black cohosh (a well known dietary supplement). Their structures were determined with the help of spectroscopic data including extensive 2D NMR spectroscopy. The isolates were found inactive, when tested for cytotoxic, estrogenic, and antioxidant activities in cell based assays. They were also tested for anticomplement activity against the classical pathway of complement system and only podocarpaside C (3) inhibited modest complement activity with an IC50 value of 200 microM. 相似文献
92.
Rhagodes Pocock, 1897 is the most speciose genus within the family Rhagodidae and species diagnosis is often very difficult. We found Rhagodes eylandti (Walter, 1889) for the first time again since the 1930s and redescribe some morphological features of the male and compare them with the literature. The main diagnostic characters are illustrated. 相似文献
93.
Amir Ahmad Akhavan Ali Khamesipour Yavar Rassi Shaden Kamhawi Mohammad Hossein Arandian Niloufar Jalali-zand Niloufar Shareghi Mohammad Reza Yaghoobi-Ershadi 《Experimental parasitology》2010,126(4):552-556
Many rodent species act as reservoir hosts of zoonotic cutaneous leishmaniasis in endemic areas. In the present study a simple and reliable assay based on nested PCR was developed for the detection and identification of Leishmania parasites from rodent skin samples. We designed Leishmania-specific primers that successfully amplified ITS regions of Leishmania major, Leishmania gerbilli and Leishmania turanica using nested PCR. Out of 95 field collected Rhombomys opimus, 21 were positive by microscopic examination and 48 by nested PCR. The percentage of gerbils infected with L. major, L. gerbilli and L. turanica was 3.2%, 1.1% and 27.4%, respectively. In 15.8% of the rodents, we found mixed natural infections by L. major and L. turanica, 1.1% by L. major and L. gerbilli, and 2.1% by the three species. We concluded that this method is simple and reliable for detecting and identifying Leishmania species circulating in rodent populations. 相似文献
94.
Mohammadreza Nematollahi Mohsen Razeghi Sina Mehdizadeh Hamidreza Tabatabaee Soraya Piroozi Zahra Rojhani Shirazi Ali Rafiee 《PloS one》2016,11(2)
Anterior cruciate ligament injury is a debilitating pathology which may alter lower limb coordination pattern in both intact and affected lower extremities during activities of daily living. Emerging evidence supports the notion that kinematic variables may not be a good indicator to differentiate patients with anterior cruciate ligament deficiency during step descent task. The aim of the present study was to examine alterations in kinematics as well as coordination patterns and coordination variability of both limbs of these patients during a single step descent task. Continuous relative phase technique was used to measure coordination pattern and coordination variability between a group of anterior cruciate ligament deficient (n = 23) and a healthy control group (n = 23). A third order polynomial Curve fitting was utilized to provide a curve that best fitted to the data points of coordination pattern and coordination variability of the healthy control group. This was considered as a reference to compare to that of patient group using nonlinear regression analysis. The results of the present study demonstrated an altered coordination pattern of the supporting shank-thigh and the stepping foot-shank couplings in anterior cruciate ligament deficient subjects. It was further noticed that there was an increased coordination variability in foot-shank and shank-thigh couplings of both supporting and stepping legs. There was no significant difference in the hip, knee and ankle joints kinematics in either side of these patients. Anterior cruciate ligament deficient individuals showed altered strategies in both intact and affected legs, with increased coordination variability. Kinematic data did not indicate any significant difference between the two groups. It could be concluded that more sophisticated dynamic approach such as continuous relative phase would uncover discrepancies between the healthy and anterior cruciate ligament deficient individuals. 相似文献
95.
Faramarzi MA Tabatabaei Yazdi M Amini M Zarrini G Shafiee A 《FEMS microbiology letters》2003,222(2):183-186
Microbial hydroxylation of progesterone occurred in the culture of Acremonium strictum PTCC 5282 to produce two hydroxylated pregnene-like steroids. The metabolites were purified and characterized using spectroscopic methods and identified as 15alpha-hydroxyprogesterone and 15alpha-hydroxydeoxycorticosterone. 相似文献
96.
Bouchra Benmansour Feriel Youssef Manel Ben Ali Bander Albogami Fehmi Boufahja 《Saudi Journal of Biological Sciences》2022,29(5):3610-3616
Between 2018 and 2020, 696 fish belonging to two species of sharks from the Family Triakidae (Mustelus mustelus and M. punctulatus) were collected from the coasts of Tunisia and inspected for parasites. Six copepod taxa (Perissopus dentatus Steenstrup & Lütken, 1861, Eudactylinella alba Wilson, 1932, Kroyeria lineata Van Beneden, 1853, Nesippus orientalis Heller, 1865 and Lernaeopoda galei Krøyer, 1837, Kroyeria sp.), four isopod species (Anilocra physodes (Linnaeus, 1758), Emetha audouini (H. Milne Edwards, 1840), Ceratothoa parallela (Otto, 1828) and Ceratothoa oestroides (Risso, 1816)) and two monogenean species (Erpocotyle sp1. And Erpocotyle sp2) were collected. A large number of global host records was reported, including the occurrence of E. audouini on M. mustelus and of Erpocotyle sp.2 on M. punctulatus. The study of the diversity of parasites per host species revealed that M. mustelus had a higher parasitic richness compared to M. punctulatus. In this study, it was provided for the first records on ectoparasites on Triakidae sharks from Tunisian coasts and their infection indices. 相似文献
97.
The kinetics of microbial degradation of naphthalene from a two-component non-aqueous-phase liquid (NAPL) coated onto uniformly sized nonporous particles were evaluated in a completely mixed batch reactor (CMBR) system and in flow-through column systems to examine the differences in the biodegradation kinetic coefficients, micro(max), the maximum specific growth rate coefficient, and K(s), the half saturation constant in the two systems. The values of these coefficients were estimated by nonlinear least-squares regression of the naphthalene mineralization profiles obtained from both CMBR and column biodegradation experiments. The results show that the range of values for micro(max) and K(s) obtained from column systems are very similar to the range of values obtained from CMBR systems. This suggests that coefficients estimated from CMBR or column systems are equally applicable for modeling studies. The presence of microorganisms and the development of biofilms at the NAPL-water interface reduced the mass transfer rates of naphthalene from the NAPL by 60% in CMBR and by 70% in column systems. If such changes in mass transfer coefficients are not accounted for, significantly erroneous values of biokinetic coefficients may be obtained. 相似文献
98.
99.
McCulloch CC Kay DM Factor SA Samii A Nutt JG Higgins DS Griffith A Roberts JW Leis BC Montimurro JS Zabetian CP Payami H 《Human genetics》2008,123(3):257-265
The objective of this study was to explore combined effects of four candidate susceptibility genes and two exposures on Parkinson’s
disease (PD) risk; namely, α-synuclein (SNCA) promoter polymorphism REP1, microtubule-associated protein tau (MAPT) H1/H2 haplotypes, apolipoprotein E (APOE) ε2/ε3/ε4 polymorphism, ubiquitin carboxy-terminal esterase L1 (UCHL1) S18Y variant, cigarette smoking and caffeinated coffee consumption. 932 PD patients and 664 control subjects from the NeuroGenetics
Research Consortium, with complete data on all six factors, were studied. Uniform protocols were used for diagnosis, recruitment,
data collection and genotyping. A logistic regression model which included gene-exposure interactions was applied. Likelihood
ratio tests (LRTs) were used for significance testing and Bayesian inference was used to estimate odds ratios (ORs). MAPT (P = 0.007), SNCA REP1 (P = 0.012), smoking (P = 0.001), and coffee (P = 0.011) were associated with PD risk. Two novel interactions were detected: APOE with coffee (P = 0.005), and REP1 with smoking (P = 0.021). While the individual main effects were modest, each yielding OR < 1.6, the effects were cumulative, with some combinations
reaching OR = 12.6 (95% CI: 5.9–26.8). This study provides evidence for the long-held notion that PD risk is modulated by
cumulative and interactive effects of genes and exposures. Furthermore, the study demonstrates that while interaction studies
are useful for exploring risk relationships that might otherwise go undetected, results should be interpreted with caution
because of the inherent loss of power due to multiple testing. The novel findings of this study that warrant replication are
the evidence for interaction of coffee with APOE, and of smoking with REP1 on PD risk.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
100.
Mohammed Hadi Latifi Kunalan Ganthel Shanmugam Rukmanikanthan Azura Mansor Tunku Kamarul Mehmet Bilgen 《Biomedical engineering online》2012,11(1):1-18