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1.
An intertidal oyster reef (~260 ha) was created by planting hatchery-reared seed oysters (Crassostrea rivularis) on an artificial concrete modular reef in the Deepwater Navigation Channel Regulation Project of the Yangtze River estuary. We examined the development of reef communities (oyster, barnacle and motile epibenthic macrofauna), characterized nekton use and assessed the habitat value of the constructed reef. The C. rivularis oyster population showed a rapid exponential increase with time and reached maximum density (3410 ± 241 ind./m2) and biomass (3175 ± 532 g/m2) after one year of restoration. The barnacle Balanus albicostatus was the most abundant sessile macrofauna and had a significantly greater density in the high intertidal zone than in the low intertidal zone (P < 0.05). The reef also supported diverse motile epibenthic macrofauna (11 mollusks, 11 crustaceans, 4 annelids and 2 fishes), and the reef-associated communities were numerically dominated by Neanthes japonica, Perinereis aibuhitensis, Nerita yoldi and Littorinopsis intermedia. A total of 50 nekton species (31 fishes, 9 shrimps and 10 crabs) utilized the constructed intertidal oyster reef, and grass shrimp Palaemon spp. dominated the nekton communities in term of abundance. Since the constructed intertidal oyster reef supports a variety of reef communities and abundant nektons, it should be recognized as an important and protective fish habitat in the Yangtze River estuary.  相似文献   

2.
《Aquatic Botany》2004,80(3):177-191
Lack of submerged vegetation was studied in a small, shallow, alkaline, clear-water lake with high nitrate concentration (mean 9 mg NO3–N L−1) and profuse filamentous green algae (FGA) (mainly Spirogyra sp.). A laboratory microcosm and two lake enclosure experiments were carried out using Elodea nuttallii (Planchon) St John. E. nuttallii grew about 1.7 times as well in sediment from its place of origin compared with sediment from the lake. Differential water quality had no effect, and neither sediment nor water prevented growth in the lake. Nutrient addition reduced plant growth by more than 55% because of shading from epiphytic filamentous green algae (shoot dry weight versus epiphytic algal dry weight, r = −0.491, P < 0.05). Transplanted Elodea plants grew better in enclosures in the lake than in laboratory conditions with lake water and sediment (P < 0.001, t-test). Rare Elodea individuals in the lake indicate the presence of plant propagules in the lake sediment, but excessive growth of filamentous green algae (summer mean 3.2 g dry weight m−2) significantly hamperd plant growth (shoot length reduced from 29 ± S.E.M. 1 to 25 ± 1 cm) and bird herbivory significantly reduced survival (from 82 ± 7 to 40 ± 6%) and shoot growth (from 78 ± 6 to 18 ± 5 cm) and thus eliminates establishment of even modest plant beds. Fish disturbance and sediment stability were not important. Restoration of submerged plants may require reduction of nitrate input, control of filamentous green algae and protection from birds.  相似文献   

3.
The Valdavara-1 cave, located in the westernmost part of the Iberian Peninsula, is an archaeological site that has been excavated since 2007. At least two main sedimentary units have been identified: an upper one, 30 cm-thick, that has yielded many fragments of ceramic characteristic of the Recent Prehistory (with a radiocarbon age of 4.490 ± 40 years BP), and a lower one, 90 cm-thick, separated from the upper one by an erosive discontinuity and late Pleistocene in age (radiocarbon ages between 13.770 ± 70 and 15.120 ± 70 years BP). The small-vertebrate assemblages recovered from the sieving-washing of all the sediment from the excavation campaigns include a total of at least 34 taxa (six amphibians, nine squamate reptiles, five insectivores, two chiropterans and 12 rodents). The materials from this locality constitutes the first mention in northwestern Spain for Microtus (Iberomys) cabrerae and Micromys minutus, currently absent from this area, as well as the first mention in the fossil record for Chioglossa lusitanica, Discoglossus galganoi and Chalcides striatus. In both layers, such small-vertebrate associations suggest a patchy landscape dominated by humid meadows and woodland areas, with the existence of water areas in the vicinity of the cave. The climate shows a more continental pattern during the late Pleistocene, as evidenced by the presence of Microtus arvalis, Sorex minutus and Rana temporaria, and was milder during the Recent Prehistory, with the occurrence of typically Mediterranean taxa such as Crocidura russula, Chioglossa lusitanica, Discoglossus galganoi, Rana iberica, Chalcides striatus and Timon lepidus. The amphibian and squamate associations suggest that the climate change recorded at the Valdavara-1 cave between the latest Pleistocene and Holocene levels may correspond to a difference of 0.8 °C in terms of mean annual temperature, although the difference is 2.8 °C for the mean temperature of the coldest month.  相似文献   

4.
To identify distinguishing characteristics for knee surgery patients who experience a protracted recovery process, we sought to determine if there is an association between the neuromuscular stretch reflex and psychological factors of pain perception and anxiety on the range of motion (ROM) recovery rate of post-operative anterior cruciate ligament reconstruction (ACLR) rehabilitation patients. The ACLR participants were categorized into a slow recovery group (SRG: >6 weeks to recover 0–125° knee flexion [n = 10]) and a normal recovery group (NRG: <6 weeks to recovery 0–125° knee flexion [n = 12]). Control participants (n = 22) were age, gender and activity-level matched to the surgical participants. Neuromuscular testing consisted of sagittal plane video kinematics of the Wartenberg Pendulum Test for determining lower limb stiffness indices and electromyography-monitored patellar tendon tap reflex responses. Psychological and health status assessments consisted of the State–Trait Anxiety Inventory and SF-36? Health Survey. Data revealed that neuromuscular reflex profiles, lower limb stiffness indices, pain, anxiety and SF-36? indices of function were not significantly different between the two surgical groups (SRG and NRG). The surgical groups exhibited significantly greater pain (2.67 ± 2.27 SRG, 1.49 ± 1.15 NRG) than the control group (p ? .05). SF-36? indices were significantly lower for the surgical groups for total score (546.55 ± 94.70 SRG, 577.57 ± 125.58 NRG), function 69.00 ± 20.24 SRG, 67.08 ± 19.12 NRG), role physical (53.75 ± 22.85 SRG, 53.12 ± 23.15 NRG), social (76.24 ± 25.31 SRG, 65.62 ± 27.24 NRG), and emotional (82.49 ± 19.81 SRG, 81.38 ± 23.02 NRG) subscales (p ? .05). These results suggest that neuromuscular reflex responses, visual analogue scale (VAS) pain, and anxiety are not distinguishing factors for ROM recovery rate between the SRG and NRG. Decreased SF-36? indices, including pain as it influences function, though clinically relevant factors, were not statistically associated with post-operative ROM recovery rate.  相似文献   

5.
The purpose of this study was to describe, interpret and compare the EMG activation patterns of ankle muscles – tibialis anterior (TA), peroneus longus (PL) and gastrocnemius lateralis (GL) – in volleyball players with and without ankle functional instability (FI) during landing after the blocking movement. Twenty-one players with FI (IG) and 19 controls (CG) were studied. The cycle of movement analyzed was the time period between 200 ms before and 200 ms after the time of impact determined by ground reaction forces. The variables were analyzed for two different phases: pre-landing (200 ms before impact) and post-landing (200 ms after impact). The RMS values and the timing of onset activity were calculated for the three studied muscles, in both periods and for both groups. The co-activation index for TA and PL, TA and GL were also calculated. Individuals with FI presented a lower RMS value pre-landing for PL (CG = 43.0 ± 22.0; IG = 26.2 ± 8.4, p < 0.05) and higher RMS value post-landing (CG = 47.5 ± 13.3; IG = 55.8 ± 21.6, p < 0.10). Besides that, in control group PL and GL activated first and simultaneously, and TA presented a later activation, while in subjects with FI all the three muscles activated simultaneously. There were no significant differences between groups for co-activation index. Thus, the rate of contraction between agonist and antagonist muscles is similar for subjects with and without FI but the activation individually was different. Volleyball players with functional instability of the ankle showed altered patterns of the muscles that play an important role in the stabilization of the foot–ankle complex during the performance of the blocking movement, to the detriment of the ligament complex, and this fact could explain the usual complaints in these subjects.  相似文献   

6.
Several EMG-based approaches to muscle fatigue assessment have recently been proposed in the literature. In this work, two multivariate fatigue indices developed by the authors: a generalized mapping index (GMI) and the first component of principal component analysis (PCA) were compared to three univariate indices: Dimitrov’s normalized spectral moments (NSM), Gonzalez-Izal’s waveletbased indices (WI), and Talebinejad’s fractal-based Hurst Exponent (HE). Nine healthy participants completed two repetitions of fatigue tests during isometric, cyclic and random fatiguing contractions of the biceps brachii. The fatigue assessments were evaluated in terms of a modified sensitivity to variability ratio yielding the following scores (mean ± std.dev.): PCA: (12.6 ± 5.6), GMI: (11.5 ± 5.4), NSM: (10.3 ± 5.4), WI: (8.9 ± 4.6), HE: (8.0 ± 3.3). It was shown that PCA statistically outperformed WI and HE (p < 0.01) and that GMI outperformed HE (p < 0.02). There was no statistical difference among NSM, WI and HE (p > 0.2). It was found that taking the natural logarithm of NSM and WI, although reducing the parameters’ sensitivity to fatigue, increased SVR scores by reducing variability.  相似文献   

7.
Some coral species of the genus Porites can produce thick mucous sheets that partially or completely envelope the colony’s surface. This phenomenon has been reported many times, but the cause and ecological significance remains unclear. In this study, sheet production was examined in response to elevated suspended sediment concentrations associated with a large-scale, extended dredging project on a coral reef. Approximately 400 corals at 16 locations situated from 0.2–33 km from the excavation area were examined at fortnightly intervals over the 1.5 year dredging campaign. Mucous sheets were observed on 447 occasions (from 10,600 observations), with average mucous prevalence ranging from 0–10%. Overall 74 ± 5% of the colonies <1.5 km from the dredging produced one or more sheets. High levels of mucous coverage (≥95% of the colony surface) was observed on 68 occasions, and 82% of these occurred at sites close to the dredging. Approximately 50% of colonies produced ≥3 sheets over the monitoring period, and 90% of these were located close to the dredging. In contrast, at distantly located reference sites (>20 km away), mean mucous sheet prevalence was very low (0.2% ± 0.1), no colonies produced more than 1 sheet, and only 1 colony was observed with high mucous coverage. In a laboratory-based experiment, explants of Porites spp. exposed to fine silt also produced mucous sheets (105 sheets recorded in 1100 observations), with nearly 30% of the fragments exposed to repeated sediment deposition events of 10 and 20 mg cm−2 d−1 producing 2 new sheets over the 28 day exposure period. These multiple lines of evidence suggest a close association between mucous sheet formation and sediment load, and that sheet formation and sloughing are an additional mechanism used by massive Porites spp. to clear their surfaces when sediment loads become too high. These results suggest that mucous sheet formation is an effective bioindicator of sediment exposure.  相似文献   

8.
Clitostethus arcuatus is a major, cosmopolitan predator of some Aleyrodidae. Field collected adult beetles were reared in the laboratory on different diets: Siphoninus phillyreae eggs, Trialeurodes vaporariorum eggs, Sitotroga cerealella eggs, or an artificial diet consisting of honey, yeast, and pollen. All experiments were conducted at 25 ± 2 °C, 65 ± 5% RH and a photoperiod of 16:8 (L:D) h. Female and male C. arcuatus consumed a mean (± SE) of 61 ± 0.6 and 27 ± 0.9 T. vaporariorum eggs d? 1, respectively, and a mean of 56 ± 2.2 and 29 ± 1.1 S. phillyreae eggs d? 1, respectively. Significant differences were noted between sexes and between hosts consumed by female C. arcuatus. No feeding occurred on S. cerealella eggs. Although there was a significant difference between rates of oviposition due to diet, fertility rates on different diets did not show significant differences. The sex ratio of C. arcuatus (female:male) was 51.4:48.6, 55.2:44.8, and 54.6:45:4 when adults fed on T. vaporariorum, S. phillyreae, and artificial diet, respectively. These differences were not significantly different. Average longevity (± SE) was 66.4 ± 2.6, 54.9 ± 2.5; 77.3 ± 6.9, 67.5 ± 7.2; and 86.4 ± 4.5 70.3 ± 3.6 days for female and male C. arctuatus, respectively, on T. vaporariorum, S. phillyreae and artificial diet, respectively, with significant differences between sexes and diets. Although developmental duration on T. vaporariorum was longer than ash whitefly, this difference was not significant (mean 27.68 ± 0.31 and 25.09 ± 0.21 days for predators reared on T. vaporariorum and S. phillyreae, respectively). Given its longevity and fecundity on T. vaporariorum, C. arcuatus may be a good choice for mass release on glasshouse crops infected by greenhouse whitefly.  相似文献   

9.
The 2011 Great East Japan Earthquake and the subsequent huge tsunami greatly affected both human activity and the coastal marine ecosystem along the Pacific coast of Japan. The tsunami also reached Funka Bay in northern Japan and caused serious damage to the scallop cultures there, and this tsunami was believed to have affected the coastal environments in the bay. Therefore, we investigated the changes in the spatial abundance and distribution of the toxic dinoflagellates Alexandrium tamarense cysts before the tsunami (August 2010) and after the tsunami (May 2011, August 2011, May 2012 and August 2012) in the bay. Further, monthly sampling was conducted after the tsunami to identify seasonal changes of Alexandrium catenella/tamarense cysts and vegetative cells. Significant increases were observed in the populations of A. catenella/tamarense cysts, comparing the abundances before the tsunami (in August 2010; 70 ± 61 cysts g−1 wet sediment) to those just after it (in May 2011; 108 ± 84 cysts g−1 wet sediment), and both A. tamarense bloom (a maximum density was 1.3 × 103 cells L−1) and PSP (Paralytic Shellfish Poisoning) toxin contamination of scallops (9.4 mouse unit g−1 was recorded) occurred in the bay. Seasonal sampling also revealed that the encystment of A. tamarense and the supply of the cysts to bottom sediments did not occur in the bay from September to April. These results strongly suggested that the mixing of the bottom sediments by the tsunami caused the accumulation of the toxic A. tamarense cysts in the surface of bottom sediment through the process of redeposition in Funka Bay. Moreover, this cyst deposition may have contributed to the toxic bloom formation as a seed population in the spring of 2011.  相似文献   

10.
Secoisolariciresinol diglucosides (SDGs) (S,S)-SDG-1 (major isomer in flaxseed) and (R,R)-SDG-2 (minor isomer in flaxseed) were synthesized from vanillin via secoisolariciresinol (6) and glucosyl donor 7 through a concise route that involved chromatographic separation of diastereomeric diglucoside derivatives (S,S)-8 and (R,R)-9. Synthetic (S,S)-SDG-1 and (R,R)-SDG-2 exhibited potent antioxidant properties (EC50 = 292.17 ± 27.71 μM and 331.94 ± 21.21 μM, respectively), which compared well with that of natural (S,S)-SDG-1 (EC50 = 275.24 ± 13.15 μM). These values are significantly lower than those of ascorbic acid (EC50 = 1129.32 ± 88.79 μM) and α-tocopherol (EC50 = 944.62 ± 148.00 μM). Compounds (S,S)-SDG-1 and (R,R)-SDG-2 also demonstrated powerful scavenging activities against hydroxyl [natural (S,S)-SDG-1: 3.68 ± 0.27; synthetic (S,S)-SDG-1: 2.09 ± 0.16; synthetic (R,R)-SDG-2: 1.96 ± 0.27], peroxyl [natural (S,S)-SDG-1: 2.55 ± 0.11; synthetic (S,S)-SDG-1: 2.20 ± 0.10; synthetic (R,R)-SDG-2: 3.03 ± 0.04] and DPPH [natural (S,S)-SDG-1: EC50 = 83.94 ± 2.80 μM; synthetic (S,S)-SDG-1: EC50 = 157.54 ± 21.30 μM; synthetic (R,R)-SDG-2: EC50 = 123.63 ± 8.67 μM] radicals. These results confirm previous studies with naturally occurring (S,S)-SDG-1 and establish both (S,S)-SDG-1 and (R,R)-SDG-2 as potent antioxidants and free radical scavengers for potential in vivo use.  相似文献   

11.
《Theriogenology》2008,69(9):1251-1259
Two-dimensional real-time and Doppler ultrasonography are valuable non-invasive methods to assess reproductive anatomy and physiology. In adult, postpubertal female Cebus apella (capuchin monkeys), the objectives were to determine (1) uterine and ovarian dimensions, ovarian follicular dynamics, day of ovulation, and arterial blood flow of uterus and utero-ovarian ligament during the follicular phase of the menstrual cycle and (2) the number of oocytes aspirated from antral follicles at laparotomy. Based on two-dimensional, transabdominal B-mode ultrasonography, mean (± S.E.M.) length, height, width, and volume of the uterus were 17.9 ± 0.4, 12.4 ± 0.3, 13.6 ± 0.3 mm, and 1.55 ± 0.08 mL, respectively, and of the ovary were 13.4 ± 0.2, 8.2 ± 0.1, 7.7 ± 0.1 mm, and 4.5 ± 0.2 mL. Ovarian follicles were monitored for 6 days before ovulation, which occurred on day 9.3 ± 0.5 (range, days 7–11; day 1 = start of menses), with 10 of 12 ovulations in the right ovary. Diameter and volume of the preovulatory follicle were 10.1 ± 0.2 mm and 0.55 ± 0.03 mL (on the estimated day of ovulation) and of the CL were 8.1 ± 0.4 mm and 0.3 ± 0.05 mL. Resistivity and pulsatility indices were 0.86 ± 0.02 and 2.15 ± 0.11 for uterine arteries, and were 0.69 ± 0.04 and 1.63 ± 0.15 for the utero-ovarian ligament (UOL) artery; just prior to ovulation, both indices peaked (P < 0.05) in the uterine artery ipsilateral to the side of ovulation, but both reached a nadir (P < 0.05) in the UOL artery. In the absence of ovarian stimulation, 31 oocytes (diameter, 137 ± 10 μm) were aspirated (average of 2 oocytes/(female attempt)) on days 5, 7, and 9. In conclusion, transabdominal ultrasonography facilitated assessment of reproductive anatomy and physiology in C. apella adult females. Resistance and pulsatility indices of uterine and UOL arteries changed near the time of ovulation. Dominant follicles were easiest to aspirate at 8–9 mm in diameter (∼day 9), with intact cumulus-oocyte complexes recovered from ovarian follicles 2–9 mm in diameter.  相似文献   

12.
EPA, DHA, cholesterol and phospholipid content were determined in the Trachinus draco, Trigla lyra and (wild and cultured) Pagrus pagrus muscles.The EPA and DHA levels – as determined by GC-GC/MS – in the cultured P. pagrus muscles (233.20 ± 16.3 and 399.39 ± 31.1 mg/100 g of the wet tissue respectively) were found to be significantly higher compared to the ones in the wild P. pagrus, T. draco and T. lyra (26.31 ± 2.26, 158.24 ± 10.92 mg/100 g, 28.65 ± 1.68, 155.97 ± 2.63 mg/100 g 35.66 ± 0.66 and 102.52 ± 1.71 mg/100 g of the wet muscles respectively). The amounts of cholesterol (determined by GC on a capillary column) and phospholipids in the cultured P. pagrus muscles were significantly higher (149.3 mg/100 g and 0.80 g/100 g of the wet tissue respectively) compared to the ones in the wild P. pagrus (8.73 mg/100 g and 0.40 g/100 g), T. draco (41.72 mg/100 g and 0.59 g/100 g) and T. lyra muscles (38.63 mg/100 g and 0.40 g/100 g of the wet tissue respectively).The highest DHA/EPA and ω-3/ω-6 ratios were 6.00 and 5.93 in wild P. pagrus and T. draco muscles respectively, while the lowest in cultured P. pagrus (1.71 and 1.48 respectively).  相似文献   

13.
The aim of the present study is to evaluate the transition metals overload in Abu-Qir Bay in Egypt, as compared to a less polluted area (reference area) through some biomarkers of oxidative stress. Catalase enzyme activity, malondialdehyde (MDA) concentration and DNA damage (number of apurinic/apyrimidinic sites) were the tested biomarkers. The levels of iron and copper in Mugil cephalus liver tissues were significantly higher in samples from the polluted area as compared to the reference area: Fe: 407 ± 38 vs. 216 ± 21 μg/g wet wt; p = 0.008, Cu: 54 ± 6 vs. 17.7 ± 4 μg/g wet wt; p = 0.0001. This could account for the observed increase in MDA concentration (15.7 ± 5.7 vs. 2.5 ± 0.5 U/g; p = 0.035), and the elevated number of AP sites (13.9 ± 2.6 vs. 0.37 ± 0.2 AP site/1 × 105 bp; p = 0.0001). Similarly, the activity of catalase enzyme responsible for the cellular defense was significantly high (58.3 ± 12.2 vs. 28.4 ± 4.0 U/mg; p = 0.032). The present data indicated a clear relationship between the pollution degree of the above marine environment and both biochemical and molecular responses of the piscine system.  相似文献   

14.
The suitability of frozen host larvae for rearing Pteromalus cerealellae (Ashmead) (Hymenoptera: Pteromalidae), an ectoparasitoid of Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) and other stored-product insects was investigated. The reproductive potential (number and sex ratio of progeny) of female P. cerealellae was compared on live (fresh) C. maculatus larvae (concealed within cowpea seeds) versus frozen larvae (obtained by freezing infested cowpea seeds at ?20 °C for 48 h) which were subsequently thawed and held at ambient conditions (~25 ± 1 °C, 50 ± 5% RH) for 4, 24, 48, 72, 96, and 120 h before exposure to female parasitoids. No significant differences were recorded in the numbers and sex ratios of the progeny produced by female P. cerealellae on live larvae compared to frozen host larvae that were thawed and held at ambient conditions for up to 96 h, suggesting that live and frozen larvae of C. maculatus are equally suitable for rearing P. cerealellae. However, the data showed that progeny production on frozen hosts gradually declined with thawing duration and was significantly reduced at the thawing duration of 120 h. When live and frozen host larvae were simultaneously presented together to female P. cerealellae at different exposure periods, relatively greater progeny production was recorded on live hosts than on frozen hosts at 12, 24, and 48 h of exposure. This may suggest preference of female P. cerealellae for live versus frozen host larvae. These results are discussed in relation to the life history strategy and host location behavior of P. cerealellae, and may have practical implications in the development of efficient mass rearing systems for the parasitoid.  相似文献   

15.
《Reproductive biology》2014,14(4):298-301
The acute effects of short-term glutamate administration on the number of antral follicles and ovulation rate were examined in adult goats. Neither live weight (44.5 ± 1.3 kg) nor body condition (3.3 ± 0.8 units) differed between the control (untreated) and glutamate-treated (0.175 mg/kg) animals (p > 0.05). However, the number of antral follicles (3.4 vs. 2.1, p = 0.05) and ovulation rate (2.5 vs. 1.5, p = 0.05) was higher in the glutamate-administered group than in the controls.  相似文献   

16.
The purpose of this study was to determine the impact of the core to skin temperature gradient during incremental running to volitional fatigue across varying environmental conditions. A secondary aim was to determine if a “critical” core temperature would dictate volitional fatigue during running in the heat. 60 participants (n=49 male, n=11 female; 24±5 yrs, 177±11 cm, 75±13 kg) completed the study. Participants were uniformly stratified into a specific exercise temperature group (18 °C, 26 °C, 34 °C, or 42 °C) based on a 3-mile run performance. Participants were equipped with core and chest skin temperature sensors and a heart rate monitor, entered an environmental chamber (18 °C, 26 °C, 34 °C, or 42 °C), and rested in the seated position for 10 min before performing a walk/run to volitional exhaustion. Initial treadmill speed was 3.2 km h−1 with a 0% grade. Every 3 min, starting with speed, speed and grade increased in an alternating pattern (speed increased by 0.805 km h−1, grade increased by 0.5%). Time to volitional fatigue was longer for the 18 °C and 26 °C group compared to the 42 °C group, (58.1±9.3 and 62.6±6.5 min vs. 51.3±8.3 min, respectively, p<0.05). At the half-way point and finish, the core to skin gradient for the 18 °C and 26 °C groups was larger compared to 42 °C group (halfway: 2.6±0.7 and 2.0±0.6 vs. 1.3±0.5 for the 18 °C, 26 °C and 42 °C groups, respectively; finish: 3.3±0.7 and 3.5±1.1 vs. 2.1±0.9 for the 26 °C, 34 °C, and 42 °C groups, respectively, p<0.05). Sweat rate was lower in the 18 °C group compared to the 26 °C, 34 °C, and 42 °C groups, 3.6±1.3 vs. 7.2±3.0, 7.1±2.0, and 7.6±1.7 g m−2 min−1, respectively, p<0.05. There were no group differences in core temperature and heart rate response during the exercise trials. The current data demonstrate a 13% and 22% longer run time to exhaustion for the 18 °C and 26 °C group, respectively, compared to the 42 °C group despite no differences in beginning and ending core temperatures or baseline 3-mile run time. This capacity difference appears to result from a magnified core to skin gradient via an environmental temperature advantageous to convective heat loss, and in part from an increased sweat rate.  相似文献   

17.
This study investigated the phytochemical, antioxidative, antimicrobial and cytotoxic effects of Leea indica leaf ethanol extract. Phytochemical values namely total phenolic and flavonoid contents, total antioxidant capacity, DPPH radical scavenging effect, FeCl3 reducing power, DMSO superoxide scavenging effect and Iron chelating effects were studied by established methods. Antibacterial, antifungal and cytotoxic effects were screened by disk diffusion technique, food poison technique and brine shrimp bioassay, respectively. Results showed the total phenolic content 24.00 ± 0.81 g GAE/100 g, total flavonoid content 194.68 ± 2.43 g quercetin/100 g and total antioxidant capacity 106.61 ± 1.84 g AA/100 g dry extract. Significant (P < 0.05) IC50 values compared to respective standards were recorded in DPPH radical scavenging (139.83 ± 1.40 μg/ml), FeCl3 reduction (16.48 ± 0.64 μg/ml), DMSO superoxide scavenging (676.08 ± 5.80 μg/ml) and Iron chelating (519.33 ± 16.96 μg/ml) methods. In antibacterial screening, the extract showed significant (P < 0.05) zone of inhibitions compared to positive controls Ampicillin and Tetracycline against Gram positive Bacillus subtilis, Bacillus cereus, Bacillus megaterium, and Staphylococcus aureus and Gram negative Salmonella typhi, Salmonella paratyphi, Pseudomonas aeroginosa, Shigella dysenteriae, Vibrio cholerae, and Escherichia coli. Significant minimum inhibitory concentrations compared to tetracycline were obtained against the above organisms. In antifungal assay, the extract inhibited the growth of Aspergillus flavus, Candida albicans and Fusarium equisetii by 38.09 ± 0.59, 22.58 ± 2.22, and 22.58 ± 2.22%, respectively. The extract showed a significant LC50 value compared to vincristine sulfate in cytotoxic assay. The results evidenced the potential antioxidative, antimicrobial and cytotoxic capacities of Leea inidica leaf extract to be processed for pharmaceutical use.  相似文献   

18.
The results presented describe and compare the fatty acid composition and melting properties of captive, healthy wild, and pansteatitis-affected wild crocodiles (Crocodylus niloticus). Differences in fatty acid composition between intramuscular and adipose fat is noted in captive crocodiles, and the latter differs from wild crocodiles as a result of different diets. Adipose fat of healthy wild crocodiles differs minimally from diseased ones, respectively with 37.3 ± 2.6% vs. 43.2 ± 2.3% monounsaturated fatty acids, and 43.2 ± 2.9% in dead crocodiles, while polyunsaturated fatty acids decrease from 27.3 ± 1.9% to as low as 21.9 ± 3.6% respectively. Of the unsaturated fatty acids 18:2n? 6 decreased from 6.5 ± 2.6% in unaffected crocodiles to 3.5 ± 0.6% in highly affected and 3.2 ± 0.4% in dead crocodiles, and 22:5n?3 from 2.8 ± 0.6% to 1.8 ± 0.3% and 2.2 ± 0.3% respectively. The melting properties as determined by differential scanning calorimetry show that extracted adipose fat is a small degree softer in pansteatitis-affected tissue, specifically in the temperature range 7–36 °C, and does not contribute to the hard texture noted for adipose fat tissue of pansteatitis-affected animals. A high moisture content of 51.0 ± 19.7% of the fat tissue of pansteatitis-affected animals vs.17.1 ± 8.0% of healthy ones, suggests that physiological changes due to interstitial inflammation may contribute to the hard texture.  相似文献   

19.
A library of 4,6-dihydroxypyrimidine diones (135) were synthesized and evaluated for their urease inhibitory activity. Structure-activity relationships, and mechanism of inhibition were also studied. All compounds were found to be active with IC50 values between 22.6 ± 1.14–117.4 ± 0.73 µM, in comparison to standard, thiourea (IC50 = 21.2 ± 1.3 µM). Kinetics studies on the most active compounds 27, 16, 17, 28, and 33 were performed to investigate their modes of inhibition, and dissociation constants Ki. Compounds 2, 3, 7, 16, 28, and 33 were found to be mixed-type of inhibitors with Ki values in the range of 7.91 ± 0.024–13.03 ± 0.013 µM, whereas, compounds 46, and 17 were found to be non-competitive inhibitors with Ki values in the range of 9.28 ± 0.019–13.05 ± 0.023 µM. In silico study was also performed, and a good correlation was observed between experimental and docking studies. This study is continuation of our previously reported urease inhibitory activity of pyrimidine diones, representing potential leads for further research as possible treatment of diseases caused by ureolytic bacteria.  相似文献   

20.
Isatin base Schiff bases (1–20) were synthesized, characterized by 1H NMR and EI/MS and evaluated for α-glucosidase inhibitory potential. Out of these twenty (20) compounds only six analogs showed potent α-glucosidase inhibitory potential with IC50 value ranging in between 2.2 ± 0.25 and 83.5 ± 1.0 μM when compared with the standard acarbose (IC50 = 840 ± 1.73 μM). Among the series compound 2 having IC50 value (18.3 ± 0.56 μM), 9 (83.5 ± 1.0 μM), 11 (3.3 ± 0.25 μM), 12 (2.2 ± 0.25 μM), 14 (11.8 ± 0.15 μM), and 20 (3.0 ± 0.15 μM) showed excellent inhibitory potential many fold better than the standard acarbose. The binding interactions of these active analogs were confirmed through molecular docking.  相似文献   

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