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51.
Shrimps are believed to lack an adaptive immune system and therefore rely heavily on their innate immune mechanisms to ward off pathogens. Moreover, their innate defense reactions are triggered by bacterial and fungal cell wall components such as lipopolysaccharides, peptidoglycan and β-glucans. In this study, we used microarray to examine the gene expression profile of kuruma shrimp, Marsupenaeus japonicus, after stimulation with peptidoglycan. Subsequent results show that the number of upregulated genes and percentage of differential expression (21%) was highest at day 1 poststimulation. Differentially expressed genes in day 7 and day 14, on the other hand, were 3.25% and 11.21%, respectively. Sixty-one (61) genes of unknown function were found to have responded outright to peptidoglycan (PG) stimulation. Administration of PG also caused increases in the expressions of crustin, lysozyme, and a few antibacterial peptides, all of which are known to be involved in crustacean immune response. Taken together, our results suggest that innate response in shrimp is triggered instantaneously upon exposure to a bacterial component. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
52.
Objective: EM‐652 is a pure antiestrogen in human breast and uterine cancer cells that also reduces bone loss and plasma lipid levels in the rat. This study aimed to assess the ability of EM‐652, alone or with dehydroepiandrosterone (DHEA), to prevent obesity and related metabolic abnormalities induced by an obesity‐promoting diet and ovariectomy. Research Methods and Procedures: Female rats were fed a high‐sucrose, high‐fat (HSHF) diet, were left intact or ovariectomized (OVX), and were treated with EM‐652, DHEA, or both for 20 days. Variables of energy balance and determinants of lipid metabolism and insulin sensitivity were assessed. Results: The HSHF diet (vs. chow) and OVX both increased energy intake and gain, as well as energetic efficiency. Both EM‐652 and DHEA prevented diet‐ and OVX‐induced energy gain mainly by decreasing fat deposition, without being additive. The modest EM‐652‐induced increase in liver triglycerides of intact rats was prevented by its combination with DHEA. EM‐652, but not DHEA, decreased cholesterolemia. The HSHF diet and OVX reduced insulin sensitivity, an effect that was attenuated by EM‐652 and abrogated by DHEA and EM‐652+DHEA. Treatment with EM‐652, DHEA, or their combination abolished the diet‐ and OVX‐induced increase in adipose lipoprotein lipase activity that accompanied fat gain. Discussion: EM‐652 is an effective agent to prevent diet‐ and OVX‐induced obesity and its associated cardiovascular risk factors such as insulin resistance. The addition of DHEA prevents hepatic lipid accumulation and further ameliorates insulin sensitivity. The beneficial metabolic effects of such combined steroid therapy may, therefore, eventually prove to be clinically relevant.  相似文献   
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Lysozyme is an enzyme that cleaves the β-1,4-glycosidic linkages between N-acetylmuramic acid and N-acetylglucosamine in peptidoglycan, leading to bacterial lysis. Recently, lysozyme has been found to have anti-HIV and anti-cancer properties in mammals. However, most functional analyses were done in vitro using purified or recombinant lysozyme protein. Here, we used RNA interference to silence c-type lysozyme expression in penaeid shrimp, Marsupenaeus japonicus, to analyze the function of lysozyme in vivo. Silencing of lysozyme expression by dsRNA lysozyme (dsLYZ) led to 100% mortality without any artificial bacterial infection in 5 days. Lysozyme deficiency caused the number of hemocytes in hemolymph to decrease from 1.3 × 10(7) to 2.3 × 10(6) cells/ml and caused the number of bacteria to increase from 78 to 764 colony-forming units/ml. Suppression of bacterial growth using oxytetracycline and kanamycin showed improvement in mortality, suggesting that shrimp mortality post- dsLYZ injection can be attributed to bacterial growth in the shrimp hemolymph. The majority of the bacteria, identified by 16 S rRNA analysis, were Gram-negative species such as Vibrio and Pseudomonas. Furthermore, PKH26 staining showed that the dsLYZ-injected shrimp were unable to eliminate non pathogenic Escherichia coli or Staphylococcus aureus in 24 h. These data suggest that c-type lysozyme in shrimp serves to regulate the growth of bacterial communities, particularly Gram-negative bacteria, in the hemolymph.  相似文献   
55.
Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, is characterized by hyperandrogenism, oligo/amenorrhea, and polycystic ovaries. We aimed to determine whether low-frequency electro-acupuncture (EA) would decrease hyperandrogenism and improve oligo/amenorrhea more effectively than physical exercise or no intervention. We randomized 84 women with PCOS, aged 18-37 yr, to 16 wk of low-frequency EA, physical exercise, or no intervention. The primary outcome measure changes in the concentration of total testosterone (T) at week 16 determined by gas and liquid chromatography-mass spectrometry was analyzed by intention to treat. Secondary outcome measures were changes in menstrual frequency; concentrations of androgens, estrogens, androgen precursors, and glucuronidated androgen metabolites; and acne and hirsutism. Outcomes were assessed at baseline, after 16 wk of intervention, and after a 16-wk follow-up. After 16 wk of intervention, circulating T decreased by -25%, androsterone glucuronide by -30%, and androstane-3α,17β-diol-3-glucuronide by -28% in the EA group (P = 0.038, 0.030, and 0.047, respectively vs. exercise); menstrual frequency increased to 0.69/month from 0.28 at baseline in the EA group (P = 0.018 vs. exercise). After the 16-wk follow-up, the acne score decreased by -32% in the EA group (P = 0.006 vs. exercise). Both EA and exercise improved menstrual frequency and decreased the levels of several sex steroids at week 16 and at the 16-wk follow-up compared with no intervention. Low-frequency EA and physical exercise improved hyperandrogenism and menstrual frequency more effectively than no intervention in women with PCOS. Low-frequency EA was superior to physical exercise and may be useful for treating hyperandrogenism and oligo/amenorrhea.  相似文献   
56.
Thiosemicarbazones have become one of the promising compounds as new clinical candidates due to their wide spectrum of pharmaceutical activities. The wide range of their biological activities depends generally on their related aldehyde or ketone groups. Here, we report the pharmacological activities of some thiosemicarbazones synthesized in this work. Benzophenone and derivatives were used with N(4)-phenyl-3-thiosemicarbazide to synthesize corresponding five thiosemicarbazones (1–5). Their structures were characterized by spectrometrical methods analysis IR, NMR 1H & 13C and MS. The compounds were then screened in vitro for their antiparasitic activity and toxicity on Trypanosoma brucei brucei and Artemia salina Leach respectively. The selectivity index of each compound was also determined. Four thiosemicarbazones such as 4, 2, 3 and 1 reveal interesting trypanocidal activities with their half inhibitory concentration (IC50) equal to 2.76, 2.83, 3.86 and 8.48 μM respectively, while compound 5 (IC50 = 12.16 μM) showed a moderate anti-trypanosomal activity on parasite. In toxicity test, except compound 1, which showed a half lethal concentration LC50 >281 μM, the others exerted toxic effect on larvae with LC50 of 5.56, 13.62, 14.55 and 42.50 μM respectively for thiosemicarbazones 4, 5, 3 and 2. In agreement to their selectivity index, which is greater than 1 (SI >1), these compounds clearly displayed significant selective pharmaceutical activities on the parasite tested. The thiosemicarbazones 2–5 that displayed significant anti-trypanosomal and cytoxicity activities are suggested to have anti-neoplastic and anti-cancer activities.  相似文献   
57.
The isoenzymes of the 3β-hydroxysteroid dehydrogenase/5-ene-4-ene-isomerase (3β-HSD) gene family catalyse the transformation of all 5-ene-3β-hydroxysteroids into the corresponding 4-ene-3-keto-steroids and are responsible for the interconversion of 3β-hydroxy- and 3-keto-5-androstane steroids. The two human 3β-HSD genes and the three related pseudogenes are located on the chromosome 1p13.1 region, close to the centromeric marker D1Z5. The 3β-HSD isoenzymes prefer NAD+ to NADP+ as cofactor with the exception of the rat liver type III and mouse kidney type IV, which both prefer NADPH as cofactor for their specific 3-ketosteroid reductase activity due to the presence of Tyr36 in the rat type III and of Phe36 in mouse type IV enzymes instead of Asp36 found in other 3β-HSD isoenzymes. The rat types I and IV, bovine and guinea pig 3β-HSD proteins possess an intrinsic 17β-HSD activity psecific to 5-androstane 17β-ol steroids, thus suggesting that such “secondary” activity is specifically responsible for controlling the bioavailability of the active androgen DHT. To elucidate the molecular basis of classical form of 3β-HSD deficiency, the structures of the types I and II 3β-HSD genes in 12 male pseudohermaphrodite 3β-HSD deficient patients as well as in four female patients were analyzed. The 14 different point mutations characterized were all detected in the type II 3β-HSD gene, which is the gene predominantly expressed in the adrenals and gonads, while no mutation was detected in the type I 3β-HSD gene predominantly expressed in the placenta and peripheral tissues. The mutant type II 3β-HSD enzymes carrying mutations detected in patients affected by the salt-losing form exhibit no detectable activity in intact transfected cells, at the exception of L108W and P186L proteins, which have some residual activity (1%). Mutations found in nonsalt-loser patients have some residual activity ranging from 1 to 10% compared to the wild-type enzyme. Characterization of mutant proteins provides unique information on the structure-function relationships of the 3β-HSD superfamily.  相似文献   
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Sampling of the central region of the North Sea was carried out to study the spatial and seasonal changes of dissolved and particulate organic C (DOC and POC, respectively). The surface waters were collected during four cruises over a year (Autumn 2004–Summer 2005). DOC and POC concentrations were measured using high temperature catalytic oxidation methods. The surface water concentrations of DOC and POC were spatially and temporally variable. There were significantly different concentrations of DOC and POC between the inshore and offshore waters in winter and summer only, with no clear trend in autumn and spring. Highest mean concentrations of DOC were measured in spring with lower and similar mean concentrations for other seasons. POC showed a clear seasonal cycle throughout the year with highest surface mean concentrations found in autumn and spring, but lowest in winter and summer. The DOC distributions during autumn and spring were strongly correlated with chlorophyll suggesting extracellular release from phytoplankton was an important DOC source during these two seasons. The lower concentrations of DOC in summer were probably due to the heterotrophic uptake of labile DOC. The seasonal changes in the C:N molar ratios of surface DOM (dissolved organic matter) resulted in higher mean C:N molar ratios in spring and lower ratios in winter. These high ratios may indicate nutrient limitation of heterotrophic uptake immediately after the spring bloom. There is limited data available for DOC cycling in these productive shelf seas and these results show that DOC is a major component of the C cycle with partial decoupling of the DOC and DON cycling in the central North Sea during the spring bloom. Handling editor: Luigi Naselli-Flores  相似文献   
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