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991.
992.
Pratip Chakraborty Sanghamitra Ghosh S.K. Goswami Syed N. Kabir Baidyanath Chakravarty Kuladip Jana 《Biological trace element research》2013,152(1):9-15
Insulin resistance is a very common associate of polycystic ovary syndrome (PCOS). Pathophysiology in relation with the essential elements including copper, magnesium, zinc, manganese, chromium, and calcium has been reported in women with insulin resistance. This prospective study was designed to explore whether the women with PCOS do exhibit altered serum element levels in association with/without insulin resistance. One hundred and thirty-two women with PCOS and forty-six control women were studied. Women with PCOS were further divided based on the presence of insulin resistance (insulin resistant: n?=?50; non-insulin resistant: n?=?82). In all women, basal levels of gonadotropins, prolactin, testosterone, insulin, glucose, and the six different elements were measured. Serum levels of testosterone (p?<?0.001), luteinizing hormone (p?<?0.05), and fasting insulin (p?<?0.004) were significantly higher in the PCOS population compared to controls as well as PCOS women without insulin resistance. Women with PCOS exhibited a significantly high calcium (p?<?0.04) and lower manganese levels (p?<?0.002) when compared to controls. However, the PCOS women with insulin resistance exhibited significantly lower serum levels of magnesium and chromium (p?<?0.04), in addition to higher levels of zinc and copper (p?<?0.04). The differences in calcium (p?<?0.03) and manganese levels (p?<?0.0001) became aggravated with the presence of insulin resistance when compared to control as well as PCOS women without insulin resistance. In PCOS-associated insulin resistance, circulating serum magnesium (r?=??0.31; p?<?0.03) and chromium (r?=??0.38; p?<?0.006) status significantly correlated with fasting insulin levels. We conclude that imbalanced element status may be a key foundation for insulin resistance in PCOS. The findings in this study should be investigated with further trials in order to obtain new insights into PCOS. 相似文献
993.
Md. Wasim Siddiqui Changrime M. Momin Pinaki Acharya J. Kabir Manoj Kanti Debnath R. S. Dhua 《Acta Physiologiae Plantarum》2013,35(4):1141-1148
The changes in bioactive molecules (capsaicin, total phenol, total flavonoid, ascorbic acid and β-carotene) and antioxidant potential in Capsicum chinense Jacq. cv. Habanero were examined during nine maturity stages (at 7-day interval from fruit set). The rate of in vivo synthesis of these antioxidants increased progressively with advancing maturity. Capsaicin, ascorbic acid, and β-carotene contents increased about 3, 10, and 9 times, respectively, at 63 days after fruit set (DAFS) while the highest value for total phenol (~330 mg CE/100 g), flavonoid (~138 mg RE/100 g), DPPH radical scavenging activity (~82 %), and metal chelating activity (~75 %) recorded in 42–49 DAFS. Bioactive molecules were positively correlated with radical scavenging and metal chelating activities. The results underline the effect of maturity on the bioactive molecules and antioxidant potential suggesting that fruits at the red stage (42–49 DAFS) are optimal from the nutritional point of view. 相似文献
994.
Salt-bridges (sb) play an important role in the folding and stability of proteins. This is deduced from the evaluation of net energy in the microenvironments (ME, residues that are 4 Å away from positive and negative partners of salt-bridge and interact with them). MEs act as a determinant of net-energy due to the intrinsic features in the sequence. The stability of extremophilic proteins is due to the presence of favorable residues at the ME without any unfavorable residues. We studied a dataset of four structures from the protein data bank (PDB) and a homology model (1HM5) to gain insights on this issue. Data shows that the presence of isolated charges and polar residues in the core of extremophilic proteins helps in the formation of stable salt-bridges with reduced desolvation. Thus, site-specific mutations with favorable residues at the ME will help to develop thermo stable proteins with strong salt bridges. 相似文献
995.
Rakhra Gurseen Masih Daisy Vats Annu Vijay Aatira Ashraf Mohammad Zahid Singh Som Nath 《Biological trace element research》2020,195(1):95-104
Biological Trace Element Research - From the time of dietary intake to their utilization, the number of important interactions occurs among mineral elements, which can affect their bioavailability... 相似文献
996.
Cengiz Kaya David Higgs Muhammad Ashraf Mohammed N. Alyemeni Parvaiz Ahmad 《Physiologia plantarum》2020,168(2):256-277
There seems to be no report in the literature on the effect of melatonin (MT) in relieving the detrimental effects of combined application of salt stress (SS) and iron deficiency (ID). Therefore, the effect of MT on the accumulation/synthesis of endogenous nitric oxide (NO) and hydrogen sulphide (H2S) and how far these molecules are involved in MT-improved tolerance to the combined application of ID and SS in pepper (Capsicum annuum L) were tested. Hence, two individual trials were set up. The treatments in the first experiment comprised: Control, ID (0.1 mM FeSO4), SS (100 mM NaCl) and ID + SS. The detrimental effects of combined stresses were more prominent than those by either of the single stress, with respect to growth, oxidative stress and antioxidant defense attributes. Single stress or both in combination improved the endogenous H2S and NO, and foliar-applied MT (100 µM) led to a further increase in NO and H2S levels. In the second experiment, 0.1 mM scavenger of NO, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (cPTIO) and that of H2S, hypotuarine (HT) were applied along with MT to get further evidence whether NO and H2S are involved in MT-induced tolerance to ID and SS. MT combined with cPTIO and HT under a single or combined stress showed that NO effect was reversed by the NO scavenger, cPTIO, alone but the H2S effect was inhibited by both scavengers. These findings suggested that tolerance to ID and SS induced by MT may be involved in downstream signal crosstalk between NO and H2S. 相似文献
997.
998.
Changes in mangrove forest soils: a comparison between cultured and naturally inundated conditions 总被引:1,自引:0,他引:1
A study was carried out in three shrimp farms in a natural mangrove area at the southeastern part of Bangladesh that dealt
mainly with the changes in mangrove soil characteristics in both cultured and naturally inundated conditions. Some noticeable
changes were observed in case of soil pH, sulfate sulfur(SO4-S) and extractable aluminium (Al) where, soil pH has shown a negative correlation with the other two parameters. Al concentration
reached its minimum 145 days after pond preparation (DAP) proving that flooding for longer periods reduced the possibility
of acid and Al toxicity. Extractable sodium (Na) and potassium (K) gradually increased in the cultured ponds while in the
inundated ponds, Na concentration remained stable but K increased significantly at the end of the study period. Results of
the present study indicate that shrimp farming in an already depleted mangrove forest helps to improve soil quality but still,
other management and environmental concerns related to intensive shrimp culture are unavoidable and should be taken into account
before promoting such activities in mangrove areas. It is recommended that shrimp culture zone be established beyond the mangrove
fringe where possible, to enable mangroves to buffer aquaculture effluent.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
Mohammad Z. Ashraf Niladri S. Kar Eugene A. Podrez 《The international journal of biochemistry & cell biology》2009,41(6):1241-1244
Biologically active oxidized phospholipids can initiate and modulate many of the cellular events attributed to inflammation leading to atherosclerosis. Produced by enzymatic or non-enzymatic processes, these molecules interact with various cells via specific receptors and in general give rise to inflammatory signals. There is considerable evidence that oxidized phospholipids accumulate in vivo and play significant roles in atherosclerosis and thrombosis, suggesting that oxidized phospholipids could be biomarkers that reflect the global extent of these diseases in vivo. Thus, understanding the biosynthetic pathways, receptor specificity and signaling processes of oxidized phospholipids is important in understanding atherosclerosis, thrombosis and related inflammatory diseases. 相似文献
1000.
Ghulam Raza Aquil Siddique Imtiaz Ahmad Khan Muhammed Yasin Ashraf Abdullah Khatri 《植物学报(英文版)》2009,51(12):1080-1085
The present study aimed to quantify the methyl esters of lenoleic acid (LA), γ-lenolenic acid (LNA) and oleic acid (OL) in the oil of Brassica napus mutants. Five stable mutants (ROO-75/1, ROO-100/6, ROO-125/12, ROO-125/14, and ROO-125/17)of B. napus cv. 'Rainbow' (P) and three mutants (W97-95116, W97-0.75/11 and W97-.075/13) of B. napus cv. 'Westar' (P) at M6 stage, exhibiting better yield and yield components, were analyzed for essential fatty acids. The highest seed yield was observed in the mutant (ROO-100/6) followed by ROO-125/14 of Rainbow, that is, 34% and 32% higher than their parent plants, respectively. Westar mutant W97-75/11 also showed 30% higher seed yield than its parent plant. High performance liquid chromatography analysis of the composition of fatty acids indicated that OL was the most dominant fatty acid, ranging from 39.1 to 66.3%; LA was second (15.3-41.6%) and LNA was third (18.1-28.9%). Mutant ROO-125/14 showed higher OL contents than parent (Rainbow). These results are expected to support the approval of ROO-125/14 in the National Uniform Varietal Yield Trials (NUVYT) as a new variety based on high oil quality. 相似文献