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ABSTRACT: Among all of the decapods that have been studied, only one kind of gland, the androgenic gland, has been found attached to the subterminal ejaculatory region of the vas deferens. In the present study of the red swamp crayfish, it was found that two kinds of gland-like tissues were attached to the subterminal ejaculatory region of the vas deferens. One of the tissues, which is referred to as TIB, is located inside the body cavity, whereas the other tissue, which is referred to as TIC, is inside the coxa. The characteristics of TIB resemble those of the androgenic gland of other malacostracans. The TIC cells, however, are smaller and more basophilic due to the small size and high density of their cytoplasm and nuclei. Moreover, black fibers, similar to the nerve fibers of the ganglion, were detected among the TIC cells after Bodian's stain. The conclusion is that TIC may be a newly found male sexual characteristic and further research is needed to confirm its functions. 相似文献
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Shiro Suzuki Kunihiro Suda Nozomu Sakurai Yoshiyuki Ogata Takefumi Hattori Hideyuki Suzuki Daisuke Shibata Toshiaki Umezawa 《Journal of Wood Science》2011,57(1):40-46
Acacia mangium is a fast-growing tree widely planted in tropical countries because of its rapid growth, high wood density, high fiber quality,
and good adaptability. Despite its importance as a fiber source in the pulp and paper industry, a large-scale analysis of
expressed sequence tags (ESTs) has not been performed in A. mangium. In this study, we sequenced 10 752 clones of a normalized complementary DNA (cDNA) library prepared from A. mangium developing secondary xylem and shoot, and obtained a total of 8963 ESTs. The ESTs were assembled into 6220 unigenes comprising
1614 contigs and 4606 singletons. The unigene set was then subjected to various bioinformatic analyses. BlastN searches of
the unigene set against the Gene Index Databases of soybean, Medicago truncatula, Lotus japonicus, grape, poplar, spruce, and pine demonstrated that the largest number of unigenes shared homologies with the soybean Gene
Indices. BlastX searches against the TAIR9 peptide database enabled us to annotate the unigenes. Based on the annotation,
we discussed whether the unigenes involved in the cell cycle, cell growth, shoot apical meristem development, and cell wall
biosynthesis were present. This new genomic resource will accelerate the functional genomics of wood formation and molecular
breeding to improve the wood properties of A. mangium. 相似文献
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Kim DH Feinbaum R Alloing G Emerson FE Garsin DA Inoue H Tanaka-Hino M Hisamoto N Matsumoto K Tan MW Ausubel FM 《Science (New York, N.Y.)》2002,297(5581):623-626
A genetic screen for Caenorhabditis elegans mutants with enhanced susceptibility to killing by Pseudomonas aeruginosa led to the identification of two genes required for pathogen resistance: sek-1, which encodes a mitogen-activated protein (MAP) kinase kinase, and nsy-1, which encodes a MAP kinase kinase kinase. RNA interference assays and biochemical analysis established that a p38 ortholog, pmk-1, functions as the downstream MAP kinase required for pathogen defense. These data suggest that this MAP kinase signaling cassette represents an ancient feature of innate immune responses in evolutionarily diverse species. 相似文献
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Kubota K Ohsako S Kurosawa S Takeda K Qing W Sakaue M Kawakami T Ishimura R Tohyama C 《The Journal of reproduction and development》2003,49(5):403-412
The effect of vinclozolin (VCZ), used as a fungicide and known to have anti-androgenic effects on spermatogenesis and gene expression in the male rat testis was investigated. In Experiment 1, VCZ (100 mg/kg/day) or flutamide (FM, 25 mg/kg/day) was orally administered to male Holzman rats for six days. 8 days after the last administration (D8), a drastic increase in intratesticular testosterone was detected in FM (4.2-fold over control) but not in VCZ treated animals, whereas on D36 post-administration, both groups showed similar levels. Significant decreases in daily sperm production were seen in both VCZ and FM-treated rats on D36. Semiquantitative RT-PCR analysis with testicular and pituitary mRNAs on D8 revealed that LHbeta and FSHbeta mRNAs were increased in the pituitary by VCZ, as well as by FM. Among the four testicular steroidogenic enzyme genes, cytochrome P450 side chain cleavage (P450scc) and cytochrome P450 17alpha/C(17-20) lyase (P450c17) mRNAs were significantly increased, whereas 17beta-hydroxysteroid dehydrogenase type III (17betaHSD) mRNA was not changed. A significant increase in 3beta-hydroxysteroid dehydrogenase type I (3betaHSD) and a decrease in androgen receptor (AR) mRNA were observed only in FM treated rats. Immunohistochemistry demonstrated intense staining of P450scc in the interstitial cells of VCZ-treated testis on D8. In Experiment 2, hormone levels were measured at 1, 3, 6, 12 and 24 hours after VCZ (100 mg/kg) administration to Sprague-Dawley rats. Serum LH level remained constant for the first 3 hours and started to increase at 6 hrs. In contrast, serum and intratesticular testosterone levels increased 2-fold at 1 hr and maintained the level until 24 hrs. P450c17 mRNA level was 2-fold increased at all periods, whereas no obvious changes were detected in the other steroidogenic enzyme genes. Although not statistically significant, AR mRNA level increased 2-fold, 3 hrs after VCZ administration. These results indicate that VCZ affects the pituitary in a similar manner as FM, but functions differently on testicular gene expression. 相似文献
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Funaba M Matsumoto C Matsuki K Gotoh K Kaneko M Iriki T Hatano Y Abe M 《American journal of veterinary research》2002,63(9):1247-1251
OBJECTIVE: To compare the nutritional value of corn gluten meal (CGM) and meat meal (MM) as a dietary source of protein in dry food formulated for adult cats. ANIMALS: 8 healthy adult cats (4 males and 4 females). PROCEDURE: Diets containing CGM or MM as the main protein source were each fed for a 3-week period in a crossover study. Digestibility and nutritional balance experiments were conducted during the last 7 days of each period. Furthermore, freshly voided urine was obtained to measure urinary pH, struvite crystals, and sediment concentrations. RESULTS: Daily food intake and dry-matter digestibility were significantly higher for the MM diet. Fecal moisture content also was higher for the MM diet. Apparent nitrogen (N) absorption and N retention were higher for the MM diet, even when values were expressed as a percentage to account for differences in N intake. Urinary pH, struvite activity product, number of struvite crystals in urine, and urinary sediment concentrations were not different between diets. Retention of calcium, phosphorus, and magnesium was lower for the CGM diet, and cats lost body calcium and magnesium when fed the CGM diet. CONCLUSIONS AND CLINICAL RELEVANCE: Meat meal was superior to CGM as a protein source in dry foods formulated for cats, because dry-matter digestibility and N utilization were higher for the MM diet. In addition, net loss of body calcium and magnesium for the CGM diet suggests that mineral requirements increase when CGM is used as a protein source. 相似文献
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Following two weeks of a warm period, beech trees at the study site began leafing. However, a spring frost occurred in the cold morning of April 21, 2001 (Day111, Julian day) and killed about 80% of the fresh leaves on a 40-year-old Siebold's beech (Fagus crenata Blume) stand in Morioka, Japan. Leaves emerged on sprouts from latent buds (latent leaves) 36 days after the frost. Field measurements between 1999 and 2003 revealed the following: (1) Leaf area index was about 4 in normal years and about 1.2 in 2001. (2) The elongation of latent leaves took 55 days about 40 days longer, and they matured about 30 days faster than normal leaves in regular years. (3) Photosynthetic capacities were similar between the latent leaves in 2001 and the normal leaves in 2002 at the top of the canopy. A longer leafing period, faster maturation and sustained photosynthetic capacity of the latent leaves would be helpful to reduce the impacts of frost damage on growth. (4) The frost damage greatly reduced NPP from about 2100 DW g m−2 y−1 in the previous two years to about 1000 DW g m−2 y−1 in 2001. However, NPP recovered almost completely (about 1800 DW g m−2 y−1) in 2002. (5) Seasonal NPP increased similarly in 2001 with other years before Day150 for 40 days after the frost, and decreased afterwards. Shoot elongation also stopped at approximately Day150 in normal years. These findings suggested that radial and height growth in the early growing season was supported by the storage of previous year photosynthesis. (6) A regression growth model was created using meteorological data from 1999 and 2000, and the model was applied to data from 2001 to estimate the potential growth under normal conditions. The ratio of measured and estimated NPP changed seasonally, greater than 0.4 between Day150 and Day210, but below 0.25 between Day210 and Day250. This suggests that beech allocated more photosynthetic products for the next year's growth rather than the current growth in the latter growing season, thereby achieving the same initial growth with other years and amazing recovery in 2002. 相似文献
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Kuhara A Okumura M Kimata T Tanizawa Y Takano R Kimura KD Inada H Matsumoto K Mori I 《Science (New York, N.Y.)》2008,320(5877):803-807
Temperature is an unavoidable environmental cue that affects the metabolism and behavior of any creature on Earth, yet how animals perceive temperature is poorly understood. The nematode Caenorhabditis elegans "memorizes" temperatures, and this stored information modifies its subsequent migration along a temperature gradient. We show that the olfactory neuron designated AWC senses temperature. Calcium imaging revealed that AWC responds to temperature changes and that response thresholds differ depending on the temperature to which the animal was previously exposed. In the mutant with impaired heterotrimeric guanine nucleotide-binding protein (G protein)-mediated signaling, AWC was hyperresponsive to temperature, whereas the AIY interneuron (which is postsynaptic to AWC) was hyporesponsive to temperature. Thus, temperature sensation exhibits a robust influence on a neural circuit controlling a memory-regulated behavior. 相似文献
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We have developed a method for temporal and regional gene expression targeting (TARGET) in Drosophila and show the simultaneous spatial and temporal rescue of a memory defect. The transient expression of the rutabaga-encoded adenylyl cyclase in the mushroom bodies of the adult brain was necessary and sufficient to rescue the rutabaga memory deficit, which rules out a developmental brain defect in the etiology of this deficit and demonstrates an acute role for rutabaga in memory formation in these neurons. The TARGET system offers general utility in simultaneously addressing issues of when and where gene products are required. 相似文献