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991.
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993.
Nodulation is the predominant insect cellular immune response to bacterial and fungal infections and it can also be induced by some viral infections. Treating seventh instar larvae of greater wax moth Galleria mellonella with Bovine herpes simplex virus-1 (BHSV-1) induced nodulation reactions in a dose-dependent manner. Because eicosanoids mediate nodulation reactions to bacterial and fungal infection, we hypothesized that eicosanoids also mediate nodulation reactions to viral challenge. To test this idea, we injected G. mellonella larvae with indomethacin, a nonsteroidal anti-inflammatory drug immediately prior to intrahemocoelic injection of BHSV-1. Relative to vehicle-treated controls, indomethacin-treated larvae produced significantly reduced numbers of nodules following viral infection (down from approximately 190 nodules/larva to <50 nodules/larva). In addition to injection treatments, increasing dietary indomethacin dosages (from 0.01% to 1%) were associated with decreasing nodulation (by 10-fold) and phenoloxidase activity (by 3-fold) reactions to BHSV-1 injection. We infer from these findings that cyclooxygenase products, prostaglandins, mediate nodulation response to viral infection in G. mellonella. 相似文献
994.
995.
The experiment was conducted to study the effects of supplementing a broiler starter diet with the probiotic Enterococcus faecium NCIMB 10415 and dried whey (80% lactose) on chick performance, gut histomorphology and intestinal microbiota. One-day-old male Ross 308 strain broiler chickens were fed diets containing: (i) control feed, (ii) control + 3.5% dried whey, (iii) control + 0.2% E. faecium, and (iv) control + 3.5% dried whey + 0.2% E. faecium. Birds were maintained in battery brooders confined in an environmentally controlled experimental room. The experiment lasted for 21 days. Birds fed E. faecium or E. faecium + dried whey exhibited significantly improved weight gain and feed conversion rate (FCR). Weight gain and FCR of treatment groups 1-4 were 628.7, 657.8, 690.9, 689.3 and 1.218, 1.193, 1.107, 1.116, respectively. Lactic acid bacteria counts in both the ileal content and excreta were significantly affected by dietary treatment. Supplementation of the E. faecium and dried whey separately and in combination increased lactic acid bacteria colonization in the ileal content from 4.2 to 5.0, 7.8 and to 5.1 log cfu/g, respectively (treatments 1-4). Similarly, supplementation of dried whey and E. faecium separately and in combination increased lactic acid bacteria in the excreta from 5.3 to 5.5, 8.0 and to 7.2 log cfu/g, respectively. Addition of the probiotic E. faecium increased villus height in the ileum (p < 0.05). Thus, supplementation of E. faecium enhanced broiler chick performance with respect to weight gain and FCR. No additive effect of E. faecium and dried whey was detected. Further studies are needed to investigate the relationship between E. faecium and dried whey with respect to gut histomorphology. 相似文献
996.
Fruit juices are targets of spoilage moulds, yeasts and acid tolerant bacteria. They might be contaminated with bacteria from raw materials, environment, packaging and during the handling of the product. These contaminations have frequently resulted in the spoilage of fruit juice and consequently commercial losses. The objective of this study was to determine the influence of propolis in apple juice againstEscherichia coli andE. coli O157:H7 strains of the spoilage and pathogenic bacteria. For this purpose, apple juice was obtained from fresh apples and then was pasteurised. The pH value, titrable acidity (as % malic acid) and Brix degree of this apple juice were 3.72±0.10, 0.67±0.05% and 12.1±0.01, respectively. Propolis extract at 1,2 and 5% concentrations were tested to determine ofE. coli andE. coli O157:H7 inhibition using paper disc diffusion method. The control treatment had no propolis extract. The apple juices were contaminated with these bacteria, and the activity of propolis was observed at first, 18th, 24th, 48th and 72nd hours at 4 and 25°C. The number of cells in the tubes was counted using serial dilution method. Results indicated that propolis extract at 2 and 5% concentrations had significant antimicrobial activity againstE. coli andE. coli O157:H7, therefore we can conclude that propolis extract is worthy of further study as a natural preservative for the foods prone to microbial spoilage. 相似文献
997.
The compact intermediate of the pea lectin found to exist at pH 2.4 was treated with low (PEG-400), medium (PEG-4000) and
high (PEG-20,000) molecular weight PEGs. The changes occurring in the secondary structure of the protein were monitored by
CD spectropolarimetry in the far-UV range, intrinsic fluorescence was used as a probe to observe the changes in the tertiary
structure which is reflected by the changes in the tryptophan environment, further ANS binding studies were made to know the
extent of exposure of the hydrophobic patches which is again indicative of the overall changes occurring in the tertiary structure
of the protein. It was found that the three PEGs altered the secondary as well as tertiary structure of the pH 2.4 intermediate
leading to the formation of three different intermediates. The intermediates were found to have non-native secondary structure
as well as non-native tertiary structure. The intermediate formed by the action of PEG-400 was due to the induction of secondary
and tertiary structure while the intermediates formed under the influence of PEG-4000 and PEG-20,000 were due to loss in secondary
structure and rearrangement in tertiary structure. Also the ANS binding studies showed the absence of any MG or MG-like structures
formed in the folding /unfolding pathway induced by PEGs. 相似文献
998.
Understanding near infrared light propagation in tissue is vital for designing next generation optical brain imaging devices. Monte Carlo (MC) simulations provide a controlled mechanism to characterize and evaluate contributions of diverse near infrared spectroscopy (NIRS) sensor configurations and parameters. In this study, we developed a multilayer adult digital head model under both healthy and clinical settings and assessed light‐tissue interaction through MC simulations in terms of partial differential pathlength, mean total optical pathlength, diffuse reflectance, detector light intensity and spatial sensitivity profile of optical measurements. The model incorporated four layers: scalp, skull, cerebrospinal‐fluid and cerebral cortex with and without a customizable lesion for modeling hematoma of different sizes and depths. The effect of source‐detector separation (SDS) on optical measurements' sensitivity to brain tissue was investigated. Results from 1330 separate simulations [(4 lesion volumes × 4 lesion depths for clinical +3 healthy settings) × 7 SDS × 10 simulation = 1330)] each with 100 million photons indicated that selection of SDS is critical to acquire optimal measurements from the brain and recommended SDS to be 25 to 35 mm depending on the wavelengths to obtain optical monitoring of the adult brain function. The findings here can guide the design of future NIRS probes for functional neuroimaging and clinical diagnostic systems. 相似文献
999.
Biologists and chemists of the world have been attracted towards marine natural products for the last five decades. Approximately
16,000 marine natural products have been isolated from marine organisms which have been reported in approximately 6,800
publications, proving marine microorganisms to be a invaluable source for the production of novel antibiotic, anti tumor, and anti
inflammatory agents. The marine fungi particularly those associated with marine alga, sponge, invertebrates, and sediments
appear to be a rich source for secondary metabolites, possessing Antibiotic, antiviral, antifungal and antiyeast activities. Besides, a
few growth stimulant properties which may be useful in studies on wound healing, carcinogenic properties, and in the study of
cancers are reported. Recent investigations on marine filamentous fungi looking for biologically active secondary metabolites
indicate the tremendous potential of them as a source of new medicines. The present study reviews about some important bioactive
metabolites reported from marine fungal strains which are anti bacterial, anti tumour and anti inflammatory in action. It highlights
the chemistry and biological activity of the major bioactive alkaloids, polyketides, terpenoids, isoprenoid and non-isoprenoid
compounds, quinones, isolated from marine fungi. 相似文献
1000.
Imran Ali Khan Noor Ahmad Shaik Nagarjuna Pasupuleti Srinivas Chava Parveen Jahan Qurratulain Hasan Pragna Rao 《Saudi Journal of Biological Sciences》2015,22(3):243-248
In this study we scrutinized the association between the A8344G/A3243G mutations and a 9-bp deletion polymorphism with gestational diabetes mellitus (GDM) in an Asian Indian population. The A3243G mutation in the mitochondrial tRNALeu(UUR) causes mitochondrial encephalopathy myopathy, lactic acidosis, and stroke-like episodes (MELAS), while the A8344G mutation in tRNALys causes myoclonus epilepsy with ragged red fibers (MERRF). We screened 140 pregnant women diagnosed with GDM and 140 non-GDM participants for these mutations by PCR-RFLP analysis. Both A3243G and A8344G were associated with GDM (A3243: OR-3.667, 95% CI = 1.001–13.43, p = 0.03; A8344G: OR-11.00, 95% CI = 0.6026–200.8, p = 0.04). Mitochondrial DNA mutations contribute to the development of GDM. Our results conclude that mitochondrial mutations are associated with the GDM women in our population. Thus it is important to screen other mitochondrial mutations in the GDM women. 相似文献