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91.
应用兔抗血清对抗鱼类和哺乳类促激素及其受体的多克隆抗体对雄性半滑舌鳎脑垂体和精巢进行了免疫组织化学定位.其结果显示GnRHR、LHR和GtH免疫活性定位在不同发育时期的腺垂体和精巢中.GtH免疫阳性细胞的数量和免疫强度随着精巢发育成熟而明显增强.同时还发现睾酮(T)和雄激素受体(AR)在半滑舌鳎精巢中的定位有别于其他鱼类,尤其是雄激素受体(AR)免疫活性在精原细胞中的数量很少.依据这个特点文中还讨论了其可能与精巢发育的关系,同时证明了半滑舌鳎精巢发育像其他硬骨鱼类一样受激素的调控.  相似文献   
92.
采用改良的DMEM(HG)培养基,建立了近江牡蛎(Crassostrea hongkongensis)鳃细胞体外培养技术,包括鳃组织块培养法和胰酶消化培养法。结果表明,组织块培养法接种6 h后,细胞开始从组织块中迁出,细胞形态较小,呈圆形、椭圆形或多边形,直径3~6μm。培养至3 d时,细胞在组织块周围形成生长晕。培养至6 d时可进行细胞传代,本次实验细胞已传至第6代。胰酶消化法接种约2 h后,细胞逐渐贴壁,从形态上主要分为两类,一类为小型细胞,形态为圆形、椭圆形或多边形,直径3~6μm,数量多,增殖速度较快;另一类为大型细胞,形态为圆形、椭圆形或多边形,直径10~20μm,部分细胞内部含有颗粒,数量较少,增殖速度较慢。培养至2 d时可进行细胞传代,传代培养物中的优势细胞皆为小型细胞。本次实验细胞已传至第6代。  相似文献   
93.
The influence of Bacillus probiotics on the digestive enzyme activity and the growth of Litopenaeus vannamei were de-termined in this study. The shrimp was treated with five percentages (1.5, 3.0, 4.5, 6.0 and 7.5) of probiotics (Bacillus spp.) supple-mented to the feed and cultured for 45d. The growth measured as the weight gain at the end of culturing was significantly (P<0.05) higher in probiotic-treated shrimps than that of the control (without receiving probiotics). Activities of protease and amylase, two digestive enzymes of the midgut gland and the intestine were significantly (P<0.05) higher in probiotic-treated shrimp than in the control.  相似文献   
94.
阐述了南海海龟资源状况,研究了海龟的生态习性及其洄游产卵规律,並进行人工孵化、培育稚龟和标志放流的试验,初步达到了资源繁殖保护的目的。  相似文献   
95.
Captive whitetip reef sharks, Triaenodon obesus,at Sea Life Park (SLP) Hawaii, Waimanalo, Hawaii develop goitre, whereas, T. obesus at the Waikiki Aquarium (WAQ), Honolulu,Hawaii do not develop goitre. To determine theeffects of natural concentrations of iodine on thereduction of goitre, two sharks from SLP with goitrewere placed in an enclosed coastal lagoon with naturalseawater. Using ultrasound measurements the twogoitres were initially 11.4 cm and 14.6 cm in depthand after 3 months decreased to 4.7 cm and 5.7 cm. Radioimmunoassay analysis of the thyroid hormoneT3 sera concentrations were initially 0.22 ng/mland 0.33 ng/ml and increased to 1.84 ng/ml after beingplaced in the lagoon. Sera T4 were initially0.93 ng/ml and 0.99 ng/ml and increased dramaticallyto 17 ng/ml and 56 ng/ml. Over the six month samplingperiod, two resident sharks in the lagoon with normalthyroids had sera T3 concentrations from 0.89ng/ml to 1.1 ng/ml, and sera T4 concentrationsfrom 3.1 ng/ml to 7.9 ng/ml. The hypothyroidcondition in the SLP goitred-sharks is likely linkedto the low environmental iodide (<0.005 M), andhigh nitrate (111 M) of SLP water. The WAQwell-water facility was characterized by anoxic waterwith high iodide (0.60 M), total iodine (1.90M), and typical nitrate (24.6 M)concentrations of interstitial groundwater. Thedifference of iodide concentration of SLP and WAQ tankwater (<0.005 M versus 0.60 M) wasdirectly related to the hydrogeology of the well-watersources. To avoid goitre in marine aquarium systems,we recommend maintaining iodide concentrations of atleast 0.15 M.  相似文献   
96.
与未经水杨酸(SA)处理的低温对照相比,0.1 mmol.L-1SA处理提高了拟南芥悬浮细胞在整个低温胁迫期间超氧化物歧化酶(SOD),过氧化物酶(POD)和过氧化氢酶(CAT)的活性,并在低温胁迫初期提高了细胞抗坏血酸过氧化物酶(APX)的活性.在抗氧化酶系统活力提升的同时,还伴随着相对电导率的降低和丙二醛(MDA)含量的减少,即细胞膜状态的恢复.相关性研究显示,膜状态的恢复与抗氧化酶系统中各类酶活力的增加呈显著正相关.上述结果表明,SA可以通过提高拟南芥悬浮细胞的抗氧化酶系统活力避免氧化损伤,从而协助膜系统在低温胁迫下的自我恢复,使细胞抗寒性得以增强.  相似文献   
97.
The aim of the present work was to determine the activities of selected antioxidant enzymes (SOD, Se-GPX, CAT) in two species of bivalves, Scapharca inaequivalvis and Tapes philippinarum, from two sites of the lagoon of Venice that are characterized by different pO(2) (Marghera and Chioggia). The specimens were collected at four times during a 1-year period. In the two species studied, enzyme activities were found to be present in both digestive glands and gills, but with some species-specific differences that may also represent a different adaptation to seasonal variations. The presence of high SOD activities in the gills of both species may be related to their physiological role in respiration. Scapharca inaequivalvis is less sensitive than T. philippinarum to environmental changes, perhaps due to the presence of hemoglobins in this species. Moreover, in the digestive gland of T. philippinarum we found a significant negative correlation between the activities of SOD and GPX that may indicate the presence of oxidative stress. Some correlations between temperature/dissolved oxygen and antioxidant enzyme activity were present in specimens sampled in Marghera. Only GPX adequately responded to changes in dissolved oxygen and temperature, while the decrease in the activity of SOD and CAT in winter may be directly responsible for an enhanced susceptibility of mussels to oxidative stress during this period. We can conclude that the observed differences between Chioggia and Marghera are due to different concentrations of dissolved oxygen. Marghera is an appropriate location to study seasonal variations in water temperature. In fact, in this site, the differences between hot and cold months are quite evident.  相似文献   
98.
Effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor Ⅱ(IGF-Ⅱ) on cartilage cells from proboscis of skate, Raja porasa Glinther, were investigated in this study. The cartilage cells were cultured in 20% FBS-supplemented MEM medium at 24℃. Twelve hours after culture initiation, the cartilage cells were treated with bFGF and IGF-Ⅱ at different concentration combinations. It was found that 20 ng/ml of bFGF or 80 ng/ml of IGF-Ⅱ was enough to have obvious stimulating effect on the growth and division of skate cartilage cells. Test of bFGF and IGF-Ⅱ together, revealed that 20 ng/ml of bFGF and 80 ng/ml of IGF-Ⅱ together had the best stimulating effect on the growth and division of skate cartilage cells. The cartilage cells cultured could form a monolayer at day 7.  相似文献   
99.
100.
We consider the general atmospheric circulation within the deductive framework of our climate theory. The preceding three parts of this theory have reduced the troposphere to the tropical and polar air masses and determined their temperature and the surface latitude of their dividing boundary, which provide the prior thermal constraint for the present dynamical derivation. Drawing upon its similar material conservation as the thermal property, the (columnar) potential vorticity (PV) is assumed homogenized as well in air masses, which moreover has a zero tropical value owing to the hemispheric symmetry. Inverting this PV field produces an upper-bound zonal wind that resembles the prevailing wind, suggesting that the latter may be explained as the maximum macroscopic motion extractable by random eddies – within the confine of the thermal differentiation.With the polar front determined in conjunction with the zonal wind, the approximate leveling of the isobars at the surface and high aloft specifies the tropopause, which is colder and higher in the tropics than in the polar region. The zonal wind drives the meridional circulation via the Ekman dynamics, and the preeminence of the Hadley cell stems from the singular Ekman convergence at the equator that allows it to supply the upward mass flux in the ITCZ demanded by the global energy balance.  相似文献   
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