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321.
Ma Q  Liu S  Zhuang Z  Lin L  Sun Z  Liu C  Ma H  Su Y  Tang Q 《Gene》2012,493(1):92-104
Growth hormone (GH) is a polypeptide which is an important regulator of development and somatic growth in teleosts, and may be associated with the mechanisms which drive sexual growth dimorphism in the Half-smooth tongue sole (Cynoglossus semilaevis). In this study, the full length gh cDNA was cloned from C. semilaevis by homology cloning and the rapid amplification of cDNA ends polymerase chain reaction (RACE-PCR). The full-length gh cDNA is 826 bp and contains an open reading frame (ORF) of 603 bp encoding a protein of 200 amino acids (AA). The precursor of gh consists of a 17 amino-acid signal peptide followed by a 183 amino-acid mature polypeptide. GH gene sequences obtained from female and male adults consist of 3428 bp and 3371 bp, respectively, each of which includes six exons and five introns, and the difference in the GH gene size was mainly caused by the microsatellites. When 14 tissues from females, normal males and extra-large male adults were analyzed for sex-specific tissue expression, the gh mRNA was found to be predominantly expressed in the pituitary, and the expression levels in females were 3.6 times as much as those in normal males, while the mRNA expression in extra-large males was 1.7 times as much as those in normal males. Sex differences in gh mRNA expression during development were also examined by using a full-sib family of C. semilaevis, and the gh mRNA was detected at all of the 12 time points sampled from 10 to 380 days-old. A significant increase in gh mRNA was detected starting in 80 day old fish and was then followed by a drop to very low levels starting at 230 day old fish. Differential expression indicated that the gh expression level in females was significantly higher than males (P < 0.01) at all of the stages except for 10 days-old. Two microsatellite loci were identified in the second intron of the GH gene. Using these two polymorphic markers to genotype 224 individuals, there was no significant difference between the females and males in the Bohai Sea, the Yellow Sea and the hatchery samples.  相似文献   
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The nanos gene family was essential for germ line development in diverse organisms. In the present study, the full-length cDNA of a nanos1 homologue in A. sinensis, Asnanos1, was isolated and characterized. The cDNA sequence of Asnanos1 was 1489 base pairs (bp) in length and encoded a peptide of 228 amino acid residues. Multiple sequence alignment showed that the zinc-finger motifs of Nanos1 were highly conserved in vertebrates. By RT-PCR analysis, Asnanos1 mRNAs were ubiquitously detected in all tissues examined except for the fat, including liver, spleen, heart, ovary, kidney, muscle, intestines, pituitary, hypothalamus, telencephalon, midbrain, cerebellum, and medulla oblongata. Moreover, a specific polyclonal antibody was prepared from the in vitro expressed partial AsNanos1 protein. Western blot analysis revealed that the tissue expression pattern of AsNanos1 was not completely coincided with that of its mRNAs, which was not found in fat, muscle and intestines. Additionally, by immunofluoresence localization, it was observed that AsNanos1 protein was in the cytoplasm of primary oocytes and spermatocytes. The presented results indicated that the expression pattern of Asnanos1 was differential conservation and divergence among diverse species.  相似文献   
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We analysed one nuclear gene (18S) and seven plastid markers [five protein coding (atpA, atpB, rbcL, rpoC1, rps4) and two non‐coding (trnHpsbA, trnLtrnF] for 31 members of Polypodiales and four outgroup taxa. We focused our sampling on the lindsaeoids and associated ferns in order to obtain a better understanding of the diversification of the early polypods. However, the exact phylogenetic position of Saccoloma and Cystodium remained uncertain. Based on relaxed molecular clock analyses, it appears that the crown group lindsaeoids diversified in the Caenozoic, more or less simultaneously with the main radiation of other Polypodiales, even though the original divergence between the lindsaeoid and non‐lindsaeoid polypods occurred before the end of the Jurassic. The current pantropical distribution of lindsaeoids can be explained by either long‐distance dispersal across the oceans or vicariance caused by the retreat of previously widely distributed tropical forests from higher to lower latitudes. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 170 , 489–503.  相似文献   
326.
Of great importance to clinical cancer diagnosis is the use of organic biomarkers. The detection of RNA, DNA, and protein antigen are all established methods for identifying specific cancer types and instrumental in promoting greater survivorship of the patient. Despite many decades of intense cancer research, we have yet to identify a "universal" protein or nucleic acid that allows us to diagnose more than a small subset of cancers at a time. In this review, we examine the use of localized cellular acidity as a universal marker for solid tumors, outlining some successes with a small peptide we call pHLIP, a pH-sensitive biosensor that allows us to label tumor tissue in live mice.  相似文献   
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The increasing prevalence of chronic wounds has significant financial implications for nations with advanced healthcare provision. Although the diseases that predispose to hard‐to‐heal wounds are recognized, their etiology is less well understood, partly because practitioners in wound management lack specialized diagnostic support. Prognostic indicators for healing may be inherent to wound biochemistry but remain invisible under routine clinical investigation; lactate is an example of this. In this study, lactate concentration in exudate obtained from 20 patients undergoing wound management in hospital was variable but in some cases approached or exceeded 20 mM. In vitro viability studies indicated that fibroblasts and endothelial cells tolerated low levels of lactate (1–10 mM), but cell viability was severely compromised by high lactate concentrations (=20 mM). Scratched monolayer experiments revealed that cell migration was affected earlier than viability in response to increasing lactate dose, and this was shown by immunocytochemistry to be associated with cytoskeletal disruption. A prototype enzyme‐based colorimetric assay for lactate generating a color change that was rapid in the context of clinical practise, and capable of functioning within a gel vehicle, was developed with point‐of‐care dipstick applications in mind. A randomized single‐blinded trial involving 30 volunteers and using a color chart to calibrate the assay demonstrated that lactate concentration could be reliably estimated with 5 mM precision; this suggesting that “physiological” and “pathological” lactate concentration could be distinguished. The present data suggest that a dipstick‐type colorimetric assay could comprise a viable diagnostic tool for identifying patients at‐risk from high‐wound lactate. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 917–924, 2012  相似文献   
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Leptospirosis, a zoonosis of global importance and it is underreported in India and more than 50,000 severe cases are reported each year. Here we present the evaluation of 16S rRNA based nested PCR assay for the rapid identification of human leptospires using serum and urine samples. The study includes 261 suspected cases for leptospirosis with different clinical manifestations. 16S rRNA based nested PCR assay was compared and evaluated against the conventional serological methods such as MAT and ELISA. The technique enabled amplification of a 289 bp product with notable percentage of positivity in all sample groups including 94.8 in pediatric cases, 93 in pregnant women, 94.2 in renal failure, 87.8 in jaundice and 94.6 in common febrile cases. The sensitivity and specificity was 94.4% and 100%, respectively. The technique proved to be prompt and effective for the diagnosis of leptospiral infection at the acute phase of the disease. PCR based approach detects leptospiral DNA from the clinical samples both at the acute and leptospiruria phase on comparison with its counter parts where detection is made possible only after 7 days or 7–30 days post-infection. In this regard PCR based diagnosis of leptospirosis should be made available for clinicians for the early diagnosis and prompt treatment of the disease.  相似文献   
329.
Prolidase is a multifunctional enzyme that possesses the unique ability to degrade imidodipeptides in which a proline or hydroxyproline residue is located at the C-terminal end. Prolidases have been isolated from archaea and bacteria, where they are thought to participate in proline recycling. In mammalian species, prolidases are found in the cytoplasm and function primarily to liberate proline in the final stage of protein catabolism, particularly during the biosynthesis and degradation of collagen. Collagen comprises nearly one-third of the total protein in the body, and it is essential in maintaining tissue structure and integrity. Prolidase deficiency (PD), a rare autosomal recessive disorder in which mutations in the PEPD gene affect prolidase functionality, tends to have serious and sometimes life-threatening clinical symptoms. Recombinant prolidases have many applications and have been investigated not only as a possible treatment for PD, but also as a part of anti-cancer strategies, a component of biodecontamination cocktails and in the dairy industry. This review will serve to discuss the many in vivo functions of procaryotic and eucaryotic prolidases, as well as the most recent advances in therapeutic and biotechnological application of prolidases.  相似文献   
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