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1.
The study investigated the relationship between five moult stages and the osmoregulatory capacities (OC), moisture content of hepatopancreas (HM%), hepatosomatic indices (HIwet, HIdry) and growth of 6 weight classes of 235 marron (Cherax cainii) and 235 yabbies (Cherax destructor) under laboratory conditions. In each moult stage, OC increased linearly with the increase in wet body weight. Intermoult stage C showed the highest OC significantly lower than premoult stages D0, D1, D2 and postmoult stage AB in every weight class in both crayfish. HM% decreased from AB to D2, while both HIwet and HIdry reduced from C to D2. Percentage dry matter of whole body carcass was highest in stage C and lowest during the AB stage with a significant difference between the two species. Larger than 15-g marron and yabbies differ with each other in OC, HIwet, and HIdry, moult intervals and growth rates.  相似文献   

2.
1. This paper investigates moult stage and size-specific changes in whole body composition during growth in juvenile crayfish in order to better describe the nature of growth and energy use. 2. Composition is described in terms of moult stage and size-specific wet, dry and ash-free dry weight, water, carbon, protein nitrogen, non-protein nitrogen, ash and energy. Dry weight and ash-free dry weight (AFDW) peaked in the middle and in the later stages of premoult. Both peaks were about 2–2.3 times postmoult weight. Losses in tissue weight during ecdysis were substantial in the smallest crayfish but declined with size. Water was taken up between late premoult and early postmoult. Tissue accumulation occurred primarily between B and D1.3, with further weight gain largely the result of fluid uptake. Ash increased immediately postmoult with a major peak occurring during intermoult. Mean organic carbon varied between 33 and 35.5% of the body and 49% of the exuvia. Chitin varied between 9 and 17% of body AFDW and made up about 50.5% of the exuvia. Protein content varied between 47 and 62% of body AFDW and about 25% of the exuvia. Carbon, chitin and protein were not affected by moult stage but protein declined with ocular carapace length (OCL) in larger crayfish. Mean caloric content varied between 19 and 22 J mg-1 AFDW depending on size and moult stage. Caloric content increased with OCL during premoult and early intermoult then declined with size until part of the way through premoult. 3. Relationships between protein, chitin and remaining carbon (organic carbon minus chitin) were examined. It is suggested that protein and some carbon are catabolized during the moulting process, possibly to fuel metabolism. Models are presented showing changes in proximate composition over the moult cycle for two sizes of crayfish, and tissue and energy accumulation and loss over a series of moult cycles and sizes from 3.1 mm to 17 mm OCL.  相似文献   

3.
《Gene》1999,239(2):317-324
Amino acid sequences of cellulases have been determined in insects, nematodes, plants, slime moulds and bacteria but not in crustaceans. However, cellulase activity has been demonstrated in the hepatopancreas of the red claw crayfish, Cherax quadricarinatus. In order to obtain information on the nature of this cellulase, a C. quadricarinatus hepatopancreas cDNA library was screened with a PCR product generated using degenerate oligonucleotide primers derived from conserved regions of known cellulases. Two identical 1.56 kb cDNAs with sequence similarities to known cellulases, particularly the termite endoglucanases, were identified and sequenced. The clones contain the complete cDNA open reading frame for an endo-1,4-beta-glucanase of 469 amino acids termed Cherax quadricarinatus endoglucanase (CqEG). The endogenous origin of the gene was confirmed by PCR amplification and sequencing of a 1012 bp PCR product from genomic DNA. This fragment contains four exon sequences identical to the cDNA and is interrupted by three introns of 371, 102, 194 bp respectively, with one intron exhibiting typical eukaryotic splice sites. The isolation of an endo-1,4-beta-glucanase encoding cDNA from the crayfish C. quadricarinatus provides the first endogenous cellulase sequence in a crustacean species.  相似文献   

4.
Amino acids were measured in claw muscle and haemolymph in the freshwater decapod crustacean, Cherax destructor, at different stages of the moult cycle. The total pool of amino acids in muscles from animals in intermoult (97+/-13 mmol kg(-1) muscle), premoult (80+/-20 mmol kg(-1)) and postmoult (97+/-19 mmol kg(-1)) were not significantly different. Despite the relatively stable total pool of amino acids, there were changes in the concentrations of alanine, glutamine and proline over the moult cycle. Compared to intermoult, claw muscles from animals in premoult had a lower concentration of proline, and animals in postmoult had higher concentrations of alanine and glutamine, but lower concentrations of proline. Concentrations of alanine and glutamine in claw muscle of animals in postmoult were higher and proline concentrations lower than in the same animals during the premoult stage. The concentration of proline in haemolymph was lower in animals in premoult and postmoult compared to intermoult. The total amino acid pool in the claw muscle of Cherax destructor did not change significantly over the moult which is distinctly different to the changes in amino acids reported in the claw muscles of marine decapod crustaceans.  相似文献   

5.
Moult cycle and morphogenesis in larval instars (zoea I, zoea II, megalopa) of the spider crabHyas araneus (L.) were studied in the laboratory. Changes in the epidermis and cuticle were documented photographically at daily intervals to characterize the stages of the moult cycle. Stage A (early postmoult) is a very short period during which the larva takes up water. During late postmoult (B) and intermoult (C) the endocuticle is secreted, and there is conspicuous epidermal tissue condensation and growth. The onset of early premoult (D0) is characterized by epidermal apolysis, occurring first at the bases of the setae in the telson of zoeal instars or in the rostrum of the megalopa, respectively. Intermediate premoult (D1) is the main period of morphogenesis, in particular of setogenesis: in the setae of the zoeal telson and carapace there is invagination or (in the zoea II) degeneration of epidermal tissues. Formation of new setae in the interior of epidermal tubules was observed in zoeal maxillipeds and in the antennae of the zoea II and megalopa instars. During late premoult (Stages D2–4) part of the new cuticle is secreted, and the results of morphogenesis become clearly visible. For technical reasons (rigid exoskeleton) only a preliminary account of the moult cycle in the megalopa can be given. A time schedule is suggested for the stages of the moult cycle. It is estimated that postmoult (A–B) takes ca 9 to 15 % of total instar duration, intermoult (C) ca 22 to 37 %, and premoult (D) ca 48 to 69 %. There is an increasing trend of relative portions of time (% of total instar duration) from instar to instar in Stages A–C (mainly in the latter) and a decreasing trend in Stage D (mainly in D0 and D2–4).  相似文献   

6.
The objective of this study was to elucidate the impact of lactation stage on milk composition, hematological and biochemical parameters of dairy Baladi goats under Egyptian conditions. Forty-eight Baladi goats (32.8 ± 2.9 kg of BW) were enrolled in the current study. The lactation period has been divided into three stages; early (DIM less than 80 days), Mid (DIM 80–140 days), and Late (DIM over 140 days). Baladi goats had decreased daily-MY at a rate of 18.4% and 31.9% at mid and late stages of lactation, compared with early stage, respectively (p = 0.001). Furthermore, lactose% decreased significantly with progress of lactation (p = 0.017). Total solids%, however, decreased significantly at early stage of lactation in comparison with mid and late stages (p = 0.022). On the contrary, no significant differences were found in protein, fat and SNF percentages at different stages of lactation (p = 0.836, 0.625 and 0.281, respectively). Serum glucose and total protein were significantly reduced at late stage of lactation in comparison with early and mid stages (p = 0.001 and 0.001, respectively). On the contrary, no significant differences were found for erythrocytes count, hemoglobin, serum cholesterol, catalase and triiodothyronine at different stages of lactation. There were high and positive correlations between daily-MY and serum total protein (r = 0.87, P < 0.01) and triiodothyronine (r = 0.41, P < 0.01). However, negative estimates were reported between daily-MY and triglycerides (r = ?0.55, P < 0.01) and cholesterol (r = ?0.33, P < 0.05). Our results indicate that dairy Baladi goats produce milk with relatively stable protein, fat and solid not fat (SNF) contents at the different stages of lactation, encouraging the continuous utilization of their milk in processing. Also, dairy Baladi goats seem able to maintain the most vital biochemical parameters.  相似文献   

7.

Aim

To evaluate the dose distribution to the left anterior descending (LAD) coronary artery in patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT).

Background

Postoperative radiotherapy may increase the risk of heart disease, particularly in patients with left-sided breast cancer. Clinical data on doses to the LAD are limited.

Materials and methods

Retrospective study of 14 patients who underwent postoperative 3DCRT for left breast cancer in 2014. All data were retrieved from medical records. Means, medians, ranges, and percentages were calculated.

Results

The mean dose to the LAD in patients with V25 < 1% was 0.12 cGy. Dmean, Dmax and V25 to the heart were, respectively, 3.7 Gy (range, 0.9–4.18), 40.3 Gy (9.28–62.9), and 1.59 cGy. The mean Dmean and Dmax values in the sample were 9.71 Gy and 33.2 Gy, respectively. The maximum dose to the LAD (D2%) ranged from 3.66 to 53.01 Gy. Due to the spacing of the CT slices (5 mm), it was not possible to completely contour the entire artery. The mean dose to the heart (3.3 Gy) was considered acceptable.

Conclusions

The maximum dose to the LAD was as high as 53 Gy, suggesting an increased risk of cardiac morbidity. This study underscores the value of contouring the LAD and the value of the breath hold technique to reduce maximum cardiac doses. Smaller CT cuts (2.5 mm) can improve contouring. Larger studies with long-term follow up are needed to determine the radiation tolerance dose for the LAD.  相似文献   

8.
The moult-staging technique was used to determine the main moult stages (MS) and their duration in laboratory-reared juveniles and subadults of Mysis mixta and Neomysis integer. The relative duration of each stage was similar for both species with premoult occupying the major part of the moult cycle (51% and 44% for M. mixta and N. integer, respectively), followed by postmoult (26% and 34%) and intermoult (23% and 22%). Effects of temperature and feeding regimes on the chronology of the moult cycle were investigated. When the duration of the moult cycle (MCD) was extended by manipulating the feeding regime, animals prolonged their late postmoult and early premoult stages. At 12 and 5 °C, no specific moult stage varied in relative duration as long as food supply was high. Field application of moult staging for growth assessment was tested using wild-caught M. mixta. The MCD estimated via moulting experiments was compared to that obtained by analyzing moult stage distribution combined with the experimentally obtained data on stage duration. Close correspondence between two methods of MCD assessment was observed with moult-staging technique being particularly useful in situations when conducting of experiments immediately after collection is not feasible.  相似文献   

9.
Balanced nutrition is fundamental to health and immunity. For herbivorous insects, nutrient-compositional shifts in host plants due to elevated atmospheric CO2 concentrations and temperature may compromise this balance. Therefore, understanding their immune responses to such shifts is vital if we are to predict the outcomes of climate change for plant–herbivore–parasitoid and pathogen interactions. We tested the immune response of Paropsis atomaria Olivier (Coleoptera: Chrysomelidae) feeding on Eucalyptus tereticornis Sm. seedlings exposed to elevated CO2 (640 μmol mol−1; CE) and temperature (ambient plus 4 °C; TE). Larvae were immune-challenged with a nylon monofilament in order to simulate parasitoid or pathogen attack without other effects of actual parasitism or pathology. The cellular (in vivo melanisation) and humoral (in vitro phenoloxidase PO activity) immune responses were assessed, and linked to changes in leaf chemistry. CE reduced foliar nitrogen (N) concentrations and increased C:N ratios and concentrations of total phenolics. The humoral response was reduced at CE. PO activity and haemolymph protein concentrations decreased at CE, while haemolymph protein concentrations were positively correlated with foliar N concentrations. However, the cellular response increased at CE and this was not correlated with any foliar traits. Immune parameters were not impacted by TE. Our study revealed that opposite cellular and humoral immune responses occurred as a result of plant-mediated effects at CE. In contrast, elevated temperatures within the tested range had minimal impact on immune responses. These complex interactions may alter the outcomes of parasitoid and pathogen attack in future climates.  相似文献   

10.
Six isonitrogenous and isocalorific diets supplemented with five different levels of beta –1,3 – glucan (0.08%, 0.1%, 0.2%, 0.4% and 0.8%) were formulated and tested for marron (Cherax tenuimanus) growth, survival, organosomatic indices, osmoregulatory capacity and immunological parameters (total and differential haemocyte counts, haemolymph clotting time and bacteraemia). The sixth diet without any beta – 1,3 – glucan was used as a control. Each diet was provided to 18 marron (0.47 ± 0.02 g initial weight) replicated 3 times in individual 250 L fiberglass cylindrical tanks. Each tank was provided with a biological filtration recirculating water system. After 84 days of culture, the survival and yield were higher in the marron fed 0.1% beta glucan supplemented diet. The different levels of beta glucan did not alter any of the physiological parameters of marron. However, dietary supplementation with beta glucan resulted in significantly higher (P < 0.05) total haemocyte count (THC) and granular cells. The bacteraemia rank was lower in all diets having beta glucan supplemented with more than or equal to 0.1% compared to the control and 0.08% beta glucan supplemented diets. Results suggest that dietary beta – 1,3 – glucan at a minimum concentration of 0.1–0.2% can improve the immune system of marron.  相似文献   

11.
In order to obtain high productivity for a cotton crop, one of the major requirements is to establish an adequate plant population. The use of good-quality seed may ultimately be the best approach to attain this goal problem. The objective of this research was to study the effect of N-fertilization (at rates of 95.2 and 142.8 kg of N ha?1), foliar application of K (at rates of 0, 0.38, 0.77, 1.15 kg of K2O ha?1, applied twice during square initiation and boll development stages) and the plant growth retardant (PGR), mepiquat chloride (applied twice, 75 days after planting at 0.0 [control] and 0.048 kg a.i. ha?1, and 90 days after planting at 0.0 [control] and 0.024 kg a.i. ha?1), on seed yield, viability, and seedling vigor of Egyptian cotton (Gossypium barbadense cv. Giza 86). A field experiment was conducted at the Agricultural Research Center, Giza, Egypt in two growing seasons. Growth, mineral uptake, seed yield per plant and per ha, seed weight, seed viability, seedling vigor and cool germination test performance were all found to increase significantly due to the addition of the high N-rate, the foliar application of three potassium concentrations, and the PGR mepiquat chloride. The N and K rates as well as application of mepiquat chloride had no significant effect on the germination rate index in both seasons. Under the conditions of this study, applying N at a rate of 142.8 kg ha?1 combined with spraying cotton plants with K2O at 1.15 kg ha?1 and with mepiquat chloride at 0.048 + 0.024 kg ha?1 were found to improve seed yield as well as seed viability and seedling vigor in the next season.  相似文献   

12.
A series of novel pyrazole oxime derivatives containing a substituted oxadiazole group were designed and synthesized. The bioassay results indicated that some title compounds displayed good acaricidal and insecticidal activities against Tetranychus cinnabarinus, Aphis medicaginis, Oriental armyworm, and Nilaparvata lugens. Especially, compounds 7a, 7b, and 7c had 80%, 90%, and 90% insecticidal activities against A. medicaginis at 20 μg/mL, respectively. Interestingly, some of the designed compounds displayed wonderful fungicidal activities in vivo against cucumber Pseudoperonospora cubensis. Furthermore, compounds 7a (EC50 = 4.97 μg/mL) and 7h (EC50 = 0.51 μg/mL) showed excellent fungicidal activity against P. cubensis comparable or better than that of the control Pyraclostrobin (EC50 = 4.59 μg/mL).  相似文献   

13.
As an important member of anti-apoptotic Bcl-2 protein, myeloid cell leukemia sequence 1 (Mcl-1) protein is an attractive target for cancer therapy. In this study, a new series of pyrrolidine derivatives as Mcl-1 inhibitors were developed by mainly modifying the amino acid side chain of compound 1. Among them, compound 18 (Ki = 0.077 μM) exhibited better potent inhibitory activities towards Mcl-1 protein compared to positive control Gossypol (Ki = 0.18 μM). In addition, compound 40 possessed good antiproliferative activities against PC-3 cells (Ki = 8.45 μM), which was the same as positive control Gossypol (Ki = 7.54 μM).  相似文献   

14.
Well-preserved Ginkgo leaves with cuticle were collected from the Middle Jurassic Jiulongshan Formation in the Daohugou area, Inner Mongolia, China, which form the common elements in the Daohugou flora. Three new species of Ginkgo are recognized and their leaf morphology and cuticular structure are described for the first time. Two different pCO2 proxy models were applied to reconstruct palaeo-atmospheric CO2 concentration by using these new Ginkgo material. NLE (nearest living equivalent) suggests a semi-quantitative pCO2 estimate as 839 ± 99 ppmv with Carboniferous standardization and 419 ± 49 ppmv with Recent standardization. While Barclay’s revised SI-pCO2 regression suggests the estimates as 405 ± 71 ppmv. The results show that the pCO2 estimate is higher than today’s atmospheric CO2 concentration but lower than most of the other results on the Jurassic Period. Combined with the floristic composition, the climate at 165 Ma in the Daohugou area is inferred to be warm temperate.  相似文献   

15.
The combined effects of temperature and salinity on both immune responses and survival in air of the clam, Ruditapes philippinarum, were evaluated for the first time. The animals were kept for 7 days at three differing temperature (5 °C, 15 °C, 30 °C) and salinity values (18 psu, 28 psu, 38 psu), and effects of the resulting 9 experimental conditions on total haemocyte count (THC), Neutral Red uptake (NRU), haemolymph protein concentration, and lysozyme activity in both haemocyte lysate (HL) and cell-free haemolymph (CFH) were evaluated. The survival-in-air test was also performed. Two-way ANOVA analysis revealed that temperature influenced significantly THC and NRU, whereas salinity and temperature/salinity interaction affected NRU only. Temperature and salinity did not influence significantly HL and CFH lysozyme activity, as well as haemolymph total protein content. Survival-in-air test is widely used to evaluate general stress conditions in clams. In the present study, temperature and salinity were shown to influence the resistance to air exposure of R. philippinarum. The highest LT50 (air exposure time resulting in 50% mortality) value was recorded in clams kept at 18 psu and 15 °C, whereas the lowest value was observed in clams kept at 28 psu and 30 °C. Overall, results obtained demonstrated that temperature and salinity can affect some functional responses of haemocytes from R. philippinarum, and suggested a better physiological condition for animals kept at 15 °C temperature and 18 psu salinity.  相似文献   

16.
In the search for compounds with potential for development as positron emission tomography radioligands for brain D3 receptor imaging, a series of N-[4-(4-arylpiperazin-1-yl)butyl]arylcarboxamides with appropriate lipophilicity (2 < log P < 3.5) were synthesized and tested in vitro. Some of the final compounds showed moderate-to-high dopamine D3 receptor affinities but lacked selectivity over D2 receptors.  相似文献   

17.
We discuss the excitonic energy landscape of the typically studied wild-type (WT) Fenna-Matthews-Olson (FMO) antenna protein from the green sulfur bacterium Chlorobaculum tepidum (referred to as WTM), which is described as a mixture of intact (WTI) and destabilized (WTD) complexes. Optical spectra of WTM and the L122Q mutant (where leucine 122 near BChl 8 is replaced with glutamine) are compared to WTI FMO. We show that WTM and L122Q samples are mixtures of two subpopulations of proteins, most likely induced by protein conformational changes during the isolation/purification procedures. Absorption, emission, and HB spectra of WTM and L122Q mutant are very similar, in which the low-energy trap (revealed by the nonresonant HB spectra) shifts to higher energies as a function of fluence, supporting a mixture model. No fluence-dependent shift is observed in the WTI FMO trimers. New Hamiltonians are provided for WTI and WTD proteins. Resonant HB spectra show that the internal energy relaxation times in the WTM and L122Q mutant are similar, and depend on excitation frequency. Fast average relaxation times (excited state lifetimes) are observed for burning into the main broad absorption band near 805 nm. Burning at longer wavelengths reveals slower total dephasing times. No resonant bleach is observed at λB  803 nm, implying much faster (femtosecond) energy relaxation in this spectral range in agreement with 2D electronic spectroscopy frequency maps.  相似文献   

18.
A series of novel methyl 4-(4-amidoaryl)-3-methoxythiophene-2-carboxylate derivatives were designed against the active site of protein tyrosine phosphatise 1B (PTP1B) enzyme using MOE.2008.10. These molecules are also subjected for in silico toxicity prediction studies and considering their corresponding drug scores, it implied that, the molecules are promising as anticancer agents. The designed compounds were synthesized by using suitable methods and characterized. They were subjected to inhibitory activity against PTP1B and in vitro anticancer activity by MTT assay. Most of the tested compounds showed potent inhibitory activity against PTP1B, among the compounds tested, compound 5b exhibited the highest activity (IC50 = 5.25 µM) and remarkable cytotoxic activity at 0.09 µM of IC50 against the MCF-7 cell line. In addition to this, compound 5c also showed potential anticancer activity at 2.22 µM of IC50 against MCF-7 and 0.72 µM against HepG2 cell lines as well as PTP1B inhibitory activity at IC50 of 6.37 µM.  相似文献   

19.
The Hout-Kasef is traditional salted fermented fish product of natural fermentation of salted mullet fish of coastal area of Jazan region of Saudi Arabia. The present study was carried out to investigate the microbiological and chemical characteristic of Hout-Kasef. A total of twenty-four salted fish samples were purchased from fish market in Jazan and Abu-Arish at different times of the year. The microbial studies of salted-fermented fish revealed a total bacterial count ranging from 2.81 to 4.72 Log10 CFU/g, yeast and mold counts ranging from 0.48 to 3.14 Log10 CFU/g, total staphylococci count 2.71–3.85 Log10 CFU/g, halophile bacteria count 3.26–5.14 Log10 CFU/g, and coliforms count <1 Log10 CFU/g. However, pathogenic bacteria such as Listeria monocytogenes, Vibrio spp., Campylobacter spp. and Yersinia species were not detected. The major bacteria species isolated and identified from the salted fermented fish were Bacillus Subtilus, Bacillus mycoides, Bacillus licheniformis, Bacillus pumilus, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus xylosus, Staphylococcus saprophticus and Staphylococcus cahnii subsp cahnii. The chemical analysis of salted fermented fish showed high content of moisture (47.96%), protein (25.71%), ash (19.6%) and salt (15.19%) but low contents of lipid (7.25%). The salted-fermented fish also showed high level of total volatile basic nitrogen (78.86 mg/100 gm sample) and thiobarbutric acid number (32.32 mg malonaldehyde/kg) with a pH value of pH 6.3. Finally, this study showed the presence of gram positive and gram negative bacteria in the fish product. The predominant microorganisms found were Bacillus and Staphylococcus spp. The fish product had high content of salt and TVB-N levels.  相似文献   

20.
This study focused on understanding the termite traveling behavior. Artificial tunnels with different curvatures and base surface roughness were constructed. Each tunnel was 50 mm in length, with widths of W (W = 2, 3, or 4 mm). The distance between the two ends of the tunnel was D (D = 20, 30, 40, or 50 mm). A higher value of D means a lower curvature. The roughness, R (R = 60, 120, 240 and ∞), was generated by uniformly sanding the substrate with a sanding machine. A higher R value means a finer base surface. The symbol ∞ represents a smooth surface. Time (τ) taken by a termite to pass through the tunnel was measured. τ was longer in tunnels with a smooth surface compared with the tunnels with a rough surface. When W = 2, there was no effect of the roughness on speed. This is because the narrow tunnel width diluted the effects of the smoothness of the surface. When W = 3, τ was statistically shorter for R = 240, than for R = 60 and 120. This suggests that an appropriate surface roughness could positively contribute to the traveling speed.  相似文献   

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