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1.
An investigation on the influence of lead toxicity on some of the hepatic enzymes was studied in rats both after a shorter
interval of 15 d and after longer intervals of 60 and 90 d. Three different doses of lead as 5, 10, and 50 mg/kg body wt were
administered orally on every alternate day. Whereas significant inhibition of succinic dehydrogenase was seen following lead
poisoning, the activity acid and alkaline phosphatase increased with lead intoxication. The histoarchitecture of the liver
was grossly intact. Liver accumulated less lead compared to kidney at 60 and 90 d. 相似文献
2.
《Bioorganic & medicinal chemistry》2020,28(11):115492
Effective chemotherapy for solid cancers is challenging due to a limitation in permeation that prevents anticancer drugs from reaching the center of the tumor, therefore unable to limit cancer cell growth. To circumvent this issue, we planned to apply the drugs directly at the center by first collapsing the outer structure. For this, we focused on cell–cell communication (CCC) between N-glycans and proteins at the tumor cell surface. Mature N-glycans establish CCC; however, CCC is hindered when numerous immature N-glycans are present at the cell surface. Inhibition of Golgi mannosidases (GMs) results in the transport of immature N-glycans to the cell surface. This can be employed to disrupt CCC. Here, we describe the molecular design and synthesis of an improved GM inhibitor with a non-sugar mimic scaffold that was screened from a compound library. The synthesized compounds were tested for enzyme inhibition ability and inhibition of spheroid formation using cell-based methods. Most of the compounds designed and synthesized exhibited GM inhibition at the cellular level. Of those, AR524 had higher inhibitory activity than a known GM inhibitor, kifunensine. Moreover, AR524 inhibited spheroid formation of human malignant cells at low concentration (10 µM), based on the disruption of CCC by GM inhibition. 相似文献
3.
《Saudi Journal of Biological Sciences》2020,27(9):2251-2260
Doxorubicin (DOX) is an anthracycline drug used for cancer treatment. However, its treatment is contiguous with toxic effects. We examined the nephroprotective potential of A. hydaspica polyphenol-rich ethyl acetate extract (AHE) against DOX persuaded nephrotoxicity. 36 male Sprague Dawley rats were randomly assorted into 6 groups. Control group received saline; DOX group: 3 mg/kg b.w. dosage of DOX intraperitoneally for 6 weeks (single dose/week). In co-treatment groups, 200 and 400 mg/kg b.w AHE was given orally for 6 weeks in concomitant with DOX (3 mg/kg b.w, i.p. injection per week) respectively. Standard group received silymarin 400 mg/kg b.w daily + DOX (single dose/week). Biochemical kidney function tests, oxidative stress markers, genotoxicity, antioxidant enzyme status, and histopathological changes were examined. DOX caused significant body weight loss and decrease kidney weight. DOX-induced marked deterioration in renal function indicators in both urine and serum, i.e., PH, specific gravity, total protein, albumin, urea, creatinine, uric acid, globulin, blood urea nitrogen, etc. Also, DOX treatment increases renal tissue oxidative stress markers, while lower antioxidant enzymes in tissue along with degenerative alterations in the renal tissue compared to control rats. AHE co-treatment ameliorates DOX-prompted changes in serum and urine chemistry. Likewise, AHE treatment decreases sensitive markers of oxidative stress and prevented DNA damages by enhancing antioxidant enzyme levels. DOX induction in rats also caused DNA fragmentation which was restored by AHE co-treatment. Moreover, the histological observations evidenced that AHE effectively rescued the kidney tissue from DOX interceded oxidative damage. Our results suggest that co-treatment of AHE markedly improve DOX-induced deleterious effects in a dose-dependent manner. The potency of AHE co-treatment at 400 mg/kg dose is similar to silymarin. These outcomes revealed that A. hydaspica AHE extract might serve as a potential adjuvant that avoids DOX-induced nephrotoxicity. 相似文献
4.
Received 20 September 2001/ Accepted in revised form 10 October 2001 相似文献
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The interactions of the cellulose molecule with several anions, including acetate , alkyl phosphate, tetrafluoroborate and hexafluorophosphate anions which are most commonly involved in the imidazolium ionic liquids (ILs), have been studied by performing density functional theory calculations. Based on calculated geometries, energies, IR characteristics, and electronic properties of the cellulose-anion complexes, it is found that the strength of interactions of anions with cellulose follows the order: acetate anion > alkyl phosphate anion > tetrafluoroborate anion > hexafluorophosphate anion, which is consistent with the experimentally observed solubility trend of cellulose in the corresponding imidazolium-based ILs. The present study may provide basic aids to some extent for understanding the dissolution behavior of cellulose in the imidazolium-based ILs. 相似文献
7.
Minhang Xin 《Steroids》2010,75(1):53-7742
An efficient and practical scheme to synthesize 2-methoxyestradiol has been developed. The key step was the copper-mediated methoxylation using ethyl acetate as a co-catalyst to introduce a methoxyl group. These synthetic procedures of four steps from 17β-estradiol as starting material gave 2-methoxyestradiol with a 61% overall yield. 相似文献
8.
Summary A rapid exchange procedure using ammonium acetate as an extractant was developed for measurement of cation exchange capacity
(CEC) of plant roots. The CEC values obtained with 1∶100 and 1∶200 root/solution ratios were almost equal, though the values
increased with length of the time of immersion in both the root/solution ratios. The method gave higher CEC values with fresh
roots as compared to dried roots. However, dried milled and dried unmilled roots gave identical values. 相似文献
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