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201.
Coxiella burnetii, an obligate intracellular bacterium of worldwide distribution, is responsible for Q fever. Domestic ruminants are the main source of infection for humans. The objectives of this study were to determine (1) whether C. burnetii would adhere to the intact zona pellucida (ZP-intact) of early in vitro–produced bovine embryos; (2) whether the bacteria would adhere to or infect the embryos (ZP-free) after in vitro infection; and (3) the efficacy of the International Embryo Transfer Society (IETS) washing protocol. One hundred and sixty, eight- to 16-cell bovine embryos produced in vitro, were randomly divided into 16 batches of 10 embryos. Twelve batches (eight ZP-intact and four ZP-free) were incubated in a medium containing C. burnetii CbB1 (Infectiologie Animale et Santé Publique, Institut National de Recherche Agronomique Tours, France). After 18 hours of incubation at 37 °C and 5% CO2 in air, the embryos were washed in 10 successive baths of a PBS and 5% fetal calf serum solution in accordance with the IETS guidelines. In parallel, four batches (two ZP-intact and two ZP-free) were subjected to similar procedures but without exposure to C. burnetii to act as controls. Ten washing fluids from each batch were collected and centrifuged for 1 hour at 13,000× g. The embryos and wash pellets were tested using conventional polymerase chain reaction. C. burnetii DNA was found in all ZP-intact and ZP-Free embryos after 10 successive washes. It was also detected in the first four washing fluids for ZP-intact embryos and in the 10th wash fluid for two of the four batches of ZP-free embryos. In contrast, none of the embryos or their washing fluids in the control batches were DNA positive. These results demonstrate that Cburnetii adheres to and/or penetrates the early embryonic cells and the ZP of in vitro bovine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS for bovine embryos, failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor cows to healthy recipients and/or their offspring. Further studies are required to investigate whether enzymatic and/or antibiotic treatment of bovine embryos infected by C. burnetii would eliminate the bacteria from the ZP and to verify if similarly results are obtained with in vivo–derived embryos.  相似文献   
202.
203.
In mammals, two carotenoid cleaving oxygenases are known; beta-carotene 15,15′-monooxygenase (BCMO1) and beta-carotene 9′,10′-oxygenase (BCO2). BCMO1 is a key enzyme in vitamin A synthesis by symmetrically cleaving beta-carotene into 2 molecules of all-trans-retinal, while BCO2 is responsible for asymmetric cleavage of a broader range of carotenoids. Here, we show that the Atlantic salmon beta-carotene oxygenase (bco) gene family contains 5 members, three bco2 and two bcmo1 paralogs. Using public sequence databases, multiple bco genes were also found in several additional teleost species. Phylogenetic analysis indicates that bco2a and bco2b originate from the teleost fish specific genome duplication (FSGD or 3R), while the third and more distant paralog, bco2 like, might stem from a prior duplication event in the teleost lineage. The two bcmo1 paralogs (bcmo1 and bcmo1 like) appear to be the result of an ancient duplication event that took place before the divergence of ray-finned (Actinopterygii) and lobe-finned fish (Sarcopterygii), with subsequent nonfunctionalization and loss of one Sarcopterygii paralog. Gene expression analysis of the bcmo1 and bco2 paralogs in Atlantic salmon reveals regulatory divergence with tissue specific expression profiles, suggesting that the beta-carotene oxygenase subtypes have evolved functional divergences. We suggest that teleost fish have evolved and maintained an extended repertoire of beta-carotene oxygenases compared to the investigated Sarcopterygii species, and hypothesize that the main driver behind this functional divergence is the exposure to a diverse set of carotenoids in the aquatic environment.  相似文献   
204.
The physical and chemical properties of biochar vary based on feedstock sources and production conditions, making it possible to engineer biochars with specific functions (e.g. carbon sequestration, soil quality improvements, or contaminant sorption). In 2013, the International Biochar Initiative (IBI) made publically available their Standardized Product Definition and Product Testing Guidelines (Version 1.1) which set standards for physical and chemical characteristics for biochar. Six biochars made from three different feedstocks and at two temperatures were analyzed for characteristics related to their use as a soil amendment. The protocol describes analyses of the feedstocks and biochars and includes: cation exchange capacity (CEC), specific surface area (SSA), organic carbon (OC) and moisture percentage, pH, particle size distribution, and proximate and ultimate analysis. Also described in the protocol are the analyses of the feedstocks and biochars for contaminants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), metals and mercury as well as nutrients (phosphorous, nitrite and nitrate and ammonium as nitrogen). The protocol also includes the biological testing procedures, earthworm avoidance and germination assays. Based on the quality assurance / quality control (QA/QC) results of blanks, duplicates, standards and reference materials, all methods were determined adequate for use with biochar and feedstock materials. All biochars and feedstocks were well within the criterion set by the IBI and there were little differences among biochars, except in the case of the biochar produced from construction waste materials. This biochar (referred to as Old biochar) was determined to have elevated levels of arsenic, chromium, copper, and lead, and failed the earthworm avoidance and germination assays. Based on these results, Old biochar would not be appropriate for use as a soil amendment for carbon sequestration, substrate quality improvements or remediation.  相似文献   
205.
The vertebrate A-P axis is a time axis. The head is made first and more and more posterior levels are made at later and later stages. This is different to the situation in most other animals, for example, in Drosophila. Central to this timing is Hox temporal collinearity (see below). This occurs rarely in the animal kingdom but is characteristic of vertebrates and is used to generate the primary axial Hox pattern using time space translation and to integrate successive derived patterns (see below). This is thus a different situation than in Drosophila, where the primary pattern guiding Hox spatial collinearity is generated externally, by the gap and segmentation genes.  相似文献   
206.
The tumor suppressor TP53 gene is one of the most frequently mutated in different types of human cancer. Particularly in colorectal cancer (CRC), it is believed that TP53 mutations play a role in the adenoma–carcinoma transition of tumors during pathological process. In order to analyze TP53 expressed alleles in CRC, we examined TP53 mRNA in tumor samples from 101 patients with sporadic CRC. Samples were divided in two groups defined according to whether they exhibit positive or negative P53 protein expression as detected by immunohistochemistry (IHC). The presence of TP53 mutation was a common event in tumors with an overall frequency of 54.5%. By direct sequencing, we report 42 different TP53 sequence changes in 55 CRC patients, being two of them validated polymorphisms. TP53 mutations were more frequent in positive than in negative P53 detection group (p < 0.0001), being the precise figures 79.6% and 30.8%, respectively. In addition, the mutation profiles were also different between the two groups of samples; while most of the mutations detected in P53 positive group were missense (38 out of 39), changes in P53 negative detection group include 7 insertions/deletions, 6 missense, 2 nonsense and 1 silent mutation. As previously observed, most mutations were concentrated in regions encoding P53 DNA binding domain (DBD). Codons 175, 248 and 273 together account for 36.7% of point mutations, in agreement with previous observations provided that these codons are considered mutation hotspots. Interestingly, we detected two new deletions and two new insertions. In addition, in three samples we detected two deletions and one insertion that could be explained as putative splicing variants or splicing errors.  相似文献   
207.
We describe the case of a boy with psychomotor delay and dysmorphic features, with a germline 16q22.1 microdeletion identified by array-CGH. The deletion spans 0.24Mb and encompasses three genes (ZFP90, CDH3 and CDH1). The deletion has been demonstrated to be inherited from his mother who was affected by lobular breast cancer (LBC) without any other apparently phenotypic features. We suppose that the microdeletion, in particular ZFP90 which is cerebrally expressed, is causative for the boy's phenotype. Mental retardation in the affected boy can recognize several mechanisms such as variable expressivity, non-penetrance, multifactorial/polygenic inheritance, recessive inheritance, a second rearrangement event and epigenetics. Furthermore, we suggest that the deletion of the CDH1, a tumor suppressor gene, involved in hereditary diffuse gastric cancer (HDGC) and LBC predisposed the mother to the carcinoma.  相似文献   
208.

Aims

Considering the key role played by the apolipoprotein E (Apo E) gene in the regulation of lipid metabolism and obesity, the current study has evaluate the association between abdominal obesity and Apo E gene polymorphism in a population of Tehran.

Materials and methods

A cross-sectional study was performed on 345 men and 498 women, aged 19–86 years, selected from among participants of the Tehran Lipid and Glucose Study. The RFLP-PCR technique was employed to investigate polymorphism in the gene fragments. Based on the national survey of risk factors for non-communicable diseases of Iran, waist circumference (WC) cut off was set at 89 cm for men and 91 cm for women. The risk effect of obesity related variables and lipid profiles in two groups of WC were examined by logistic regression. For body mass index (BMI), waist to hip ratio (WHR), high-density lipoprotein-cholesterol (HDL-C), triglyceride (TG), fasting blood sugar (FBS), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and blood pressure (BP), the standard risk cut-offs were applied.

Results

Frequencies of E2, E3, and E4 alleles were 9.7, 73, and 14.6%, respectively. The presence of the E3 allele was significantly associated with higher TG level in subjects with high WC, while, the presence of E4 allele decreased the plasma HDL-C (E2:52.1 ± 13.1 vs., E3:48.9 ± 11.2 vs., E4:44.6 ± 10.6 mg/dl, p < 0.05), HDL-C2 (E2:20.4 ± 9.2 vs., E3:19.1 ± 8.8 vs., E4:16.3 ± 7.9 mg/dl, p < 0.05), and HDL-C3 (E2:32.1 ± 7.4 vs., E3:30.3 ± 6.2 vs., E4:28.3 ± 6.1 mg/dl, p < 0.05) in normal WC subjects. The presence of the E3 carrier increased the risk of having higher plasma TG, compared with the E2 carrier (95% CI OR = 1.91, 1.02–3.57; p = 0.04).

Conclusion

According to the results of this study, the E3 carrier, caused an approximately 90% increase in the levels of TG in the group with abdominal obesity.  相似文献   
209.
Macrotrachela quadricornifera, a bdelloid rotifer, is the animal model of an experiment scheduled on the International Space Station (ISS). The focus of the experiment is the role of the cytoskeleton during oogenesis and early development. Bdelloids will fly desiccated, be rehydrated on the ISS and cultivated for five generations. We present the outline of the ISS experiment, the expectations and the state-of-the-art of ground-based research run to date on the major topics of the planned experiment: anhydrobiosis and embryogenesis. Anhydrobiosis focuses on two major aspects, storage conditions that enhance recovery rate and comparison of the resistance between dormant and active rotifers to UV radiation and other environmental injuries. Embryogenesis has been approached at the morphological level under ground conditions: developing embryos have been studied by light and confocal microscopes.  相似文献   
210.
This Editorial has four goals: (1) to inform the readers of ‘Photosynthesis Research‘ about the past of the ‘Historical corner’; which began 20 years ago; (2) to encourage photosynthesis researchers and historians of science to contact me for publishing papers of historical interest; these include: (a) Obituaries and Tributes; (b) historical papers on current and past discoveries and controversies; (c) history of research in specific laboratories, or in specific countries, or at specific conferences; (d) Personal perspectives (not discussed any further); (3) to encourage researchers not to discard, but to save correspondence and data of their discoveries for the future historians by donating them to their Archives, when appropriate (not discussed any further); and (4) to reinforce to the readers that the concept of two-light reaction and two-pigment system was already there in 1959. I mention here three key papers presented at the IXth International Botanical Congress, held at Montreal Canada (in August, 1959) prior to the famous April 9, 1960 paper by Robert Hill and Fay Bendall on the ‘Z-scheme’ of photosynthesis, that was based on thermodynamic and energetic considerations.  This Historical corner Editorial is dedicated to Bessel Kok (1918–1978).  相似文献   
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