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141.
The objective of this study was to monitor ovarian function in postpartum primiparous and pluriparous Mediterranean Italian buffaloes (Bubalus bubalis) during months of increasing daylength. Ovarian ultrasound monitoring was carried out for a total of 60 days from calving in 10 primiparous and 10 pluriparous buffaloes. Progesterone was determined from calving until a week after first postpartum ovulation. The study was undertaken during months of increasing day length. Time required for complete postpartum uterine involution was 31 +/- 1.0 and 33 +/- 1.3 days in primiparous and pluriparous buffaloes respectively (P = 0.1). The first postpartum ovulation was recorded on 4 primiparous and 8 pluriparous buffaloes (P = 0.16). Time for first postpartum ovulation to occur was 25.5 +/- 6.9 and 15.5 +/- 1.3 days in primiparous and pluriparous buffaloes, respectively (P = 0.07). Overall, 8 of the 12 first postpartum ovulations (66.6%) occurred in the ovary contra-lateral to the one bearing the gravidic CL, one out of 4 in primiparous and 3 out of 8 in pluriparous buffaloes (P = 1.0). Following a first postpartum ovulation, 3 primiparous and 4 pluriparous buffaloes displayed a complete wave of follicular development leading to a new ovulation. Ovulation following parturition was not recorded in 6 primiparous and two pluriparous buffaloes for the 60 days of ultrasound monitoring. Growth rate (mm/d) and largest size (mm) of first postpartum ovulating follicle was 0.95 +/- 0.18 and 1.07 +/- 0.07 (P = 0.4), and 13.5 +/- 0.8 and 14.1 +/- 0.4 (P = 0.4) in primiparous and pluriparous buffaloes, respectively. Following calving, the total number of available antral follicles (> or =2 mm) declined gradually towards the end of the study period. Follicles greater or equal to 3 mm in diameter on the contrary showed a prominent increase in the first 2 weeks from calving. The number of follicles greater or equal to 3 mm in diameter was significantly higher in the ovary contra-lateral to the one bearing the gravidic CL. A balance in the number of such follicles was reached toward the end of the first month. In conclusion, although some follicular activity was recorded in the ovaries of all buffaloes, true postpartum resumption of cyclicity in the months of increasing daylight hours was delayed in the majority of animals.  相似文献   
142.
143.
We determined the response of the small southern pine engraver, Ips avulsus (Eichhoff); eastern fivespined ips, Ips grandicollis (Eichhoff); sixspined ips, Ips calligraphus (Germar); and pine engraver, Ips pini (Say) to the pheromones (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone in the southeastern United States. Catches of I. avulsus and I. grandicollis to baited multiple-funnel traps were increased by (+/-)-ipsenol and (+/-)-ipsdienol in Florida, Georgia, Louisiana, and North Carolina. In all four localities, the highest numbers of I. avulsus were caught in traps baited with the combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone. In Florida, the highest numbers of I. grandicollis were captured in traps baited with the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). In the remaining three localities, the largest catches of I. grandicollis occurred in traps baited with (+/-)-ipsenol alone or the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). (+/-)-Ipsdienol was the only consistent attractant for I. calligraphus and I. pini. Attraction of I. pini in North Carolina to (+/-)-ipsdienol-baited traps was synergized by lanierone but interrupted with (+/-)-ipsenol. The interruptive effect of (+/-)-ipsenol on attraction of I. pini to (+/-)-ipsdienol was negated by lanierone. (+/-)-Ipsdienol was attractive to black turpentine beetle, Dendroctonus terebrans (Olivier), in Florida but not North Carolina, whereas (+/-)-ipsdienol was attractive to I. calligraphus in Louisiana, Georgia, and Florida. Both (+/-)-ipsenol and (+/-)-ipsdienol affected catches of Gnathotrichus materiarus (Fitch) in North Carolina. Trap catches of Hylurgops rugipennis pinifex (Fitch), Hylastes salebrosus Eichhoff, and Hylastes tenuis Eichhoff were unaffected by the pheromone treatments. The combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone may be a cost-effective general lure for I. avulsus, I. grandicollis, and I. pini.  相似文献   
144.
We describe the application of an intracellular antibody capture technology (IACT) as a generic in vivo selection procedure for isolating intracellular antibodies or ICAbs. IACT was applied to the de novo selection of functional ICAbs against the microtubule-associated protein TAU, found in neurofibrillary lesions of Alzheimer's disease brains. A panel of 17 different ICAbs was created which bind TAU inside cells and the epitopes recognized by the selected ICAbs have been determined by an in vivo epitope mapping procedure. Finally, sequence analysis showed that the IACT-derived ICAbs are characterized by a common signature of conserved amino acid residues, suggesting that the IACT naturally selects a sort of "captured consensus sequence" for intracellular antibodies. The development of IACT, together with the possibility of scaling up in a high throughput and automated format, makes IACT a new enabling tool for target validation in functional genomics and global proteomics.  相似文献   
145.
A novel human X-linked gene shows placenta-specific expression and has been named PLAC1. The gene maps 65 kb telomeric to HPRT at Xq26 and has been completely sequenced at the cDNA and genomic levels. The mouse orthologue Plac1 maps to the syntenically equivalent region of the mouse X chromosome. In situ hybridization studies with the antisense mRNA during mouse embryogenesis detect Plac1 expression from 7.5 dpc (days postcoitum) to 14.5 dpc in ectoplacental cone, giant cells, and labyrinthine trophoblasts. The putative human and murine PLAC1 proteins are 60% identical and 77% homologous. Both include a signal peptide and a peptide sequence also found in an interaction domain of the ZP3 (zona pellucida 3) protein. These results make PLAC1 a marker for placental development, with a possible role in the establishment of the mother–fetus interface.  相似文献   
146.
147.
Antimetabolites are a class of effective anticancer drugs interfering in essential biochemical processes. 5-Fluorouracil (5-FU) and its prodrug Capecitabine are widely used in the treatment of several solid tumors (gastro-intestinal, gynecological, head and neck, breast carcinomas). Therapy with fluoropyrimidines is associated with a wide range of adverse effects, including diarrhea, dehydration, abdominal pain, nausea, stomatitis, and hand-foot syndrome. Among the 5-FU side effects, increasing attention is given to cardiovascular toxicities induced at different levels and intensities. Since the mechanisms related to 5-FU-induced cardiotoxicity are still unclear, we examined the effects of 5-FU on primary cell cultures of human cardiomyocytes and endothelial cells, which represent two key components of the cardiovascular system. We analyzed at the cellular and molecular level 5-FU effects on cell proliferation, cell cycle, survival and induction of apoptosis, in an experimental cardioncology approach. We observed autophagic features at the ultrastructural and molecular levels, in particular in 5-FU exposed cardiomyocytes. Reactive oxygen species (ROS) elevation characterized the endothelial response. These responses were prevented by a ROS scavenger. We found induction of a senescent phenotype on both cell types treated with 5-FU. In vivo, in a xenograft model of colon cancer, we showed that 5-FU treatment induced ultrastructural changes in the endothelium of various organs. Taken together, our data suggest that 5-FU can affect, both at the cellular and molecular levels, two key cell types of the cardiovascular system, potentially explaining some manifestations of 5-FU-induced cardiovascular toxicity.  相似文献   
148.
An important hallmark of CRC is the evasion of immune surveillance. HLA-G is a negative regulator of host’s immune response. Overexpression of HLA-G protein in primary tumour CRC tissues has already been associated to worse prognosis; however a definition of the role of immunogenetic host background is still lacking. Germline polymorphisms in the 3’UTR region of HLA-G influence the magnitude of the protein by modulating HLA-G mRNA stability. Soluble HLA-G has been associated to 3’UTR +2960 Ins/Ins and +3035 C/T (lower levels) and +3187 G/G (high levels) genotypes. HLA-G 3’UTR SNPs have never been explored in CRC outcome. The purpose of this study was to investigate if common HLA-G 3’UTR polymorphisms have an impact on DFS and OS of 253 stage II-III CRC patients, after primary surgery and ADJ-CT based on FL. The 3’UTR was sequenced and SNPs were analyzed for their association with survival by Kaplan-Meier and multivariate Cox models; results underwent internal validation using a resampling method (bootstrap analysis). In a multivariate analysis, we estimated an association with improved DFS in Ins allele (Ins/Del +Ins/Ins) carriers (HR 0.60, 95% CI 0.38–0.93, P = 0.023) and in patients with +3035 C/T genotype (HR 0.51, 95% CI 0.26–0.99, P = 0.045). The +3187 G/G mutated carriers (G/G vs A/A+A/G) were associated to a worst prognosis in both DFS (HR 2.46, 95% CI 1.19–5.05, P = 0.015) and OS (HR 2.71, 95% CI 1.16–6.63, P = 0.022). Our study shows a prognostic and independent role of 3 HLA-G 3’UTR SNPs, +2960 14-bp INDEL, +3035 C>T, and +3187 A>G.  相似文献   
149.
Undetected and untreated, low-levels of drug resistant (DR) subpopulations in clinical Mycobacterium tuberculosis (Mtb) infections may lead to development of DR-tuberculosis, potentially resulting in treatment failure. Current phenotypic DR susceptibility testing has a theoretical potential for 1% sensitivity, is not quantitative, and requires several weeks to complete. The use of “single molecule-overlapping reads” (SMOR) analysis with next generation DNA sequencing for determination of ultra-rare target alleles in complex mixtures provides increased sensitivity over standard DNA sequencing. Ligation free amplicon sequencing with SMOR analysis enables the detection of resistant allele subpopulations at ≥0.1% of the total Mtb population in near real-time analysis. We describe the method using standardized mixtures of DNA from resistant and susceptible Mtb isolates and the assay’s performance for detecting ultra-rare DR subpopulations in DNA extracted directly from clinical sputum samples. SMOR analysis enables rapid near real-time detection and tracking of previously undetectable DR sub-populations in clinical samples allowing for the evaluation of the clinical relevance of low-level DR subpopulations. This will provide insights into interventions aimed at suppressing minor DR subpopulations before they become clinically significant.  相似文献   
150.

Background

The detection of mutations in the gyrA and gyrB genes in the Mycobacterium tuberculosis genome that have been demonstrated to confer phenotypic resistance to fluoroquinolones is the most promising technology for rapid diagnosis of fluoroquinolone resistance.

Methods

In order to characterize the diversity and frequency of gyrA and gyrB mutations and to describe the global distribution of these mutations, we conducted a systematic review, from May 1996 to April 2013, of all published studies evaluating Mycobacterium tuberculosis mutations associated with resistance to fluoroquinolones. The overall goal of the study was to determine the potential utility and reliability of these mutations as diagnostic markers to detect phenotypic fluoroquinolone resistance in Mycobacterium tuberculosis and to describe their geographic distribution.

Results

Forty-six studies, covering four continents and 18 countries, provided mutation data for 3,846 unique clinical isolates with phenotypic resistance profiles to fluoroquinolones. The gyrA mutations occurring most frequently in fluoroquinolone-resistant isolates, ranged from 21–32% for D94G and 13–20% for A90V, by drug. Eighty seven percent of all strains that were phenotypically resistant to moxifloxacin and 83% of ofloxacin resistant isolates contained mutations in gyrA. Additionally we found that 83% and 80% of moxifloxacin and ofloxacin resistant strains respectively, were observed to have mutations in the gyrA codons interrogated by the existing MTBDRsl line probe assay. In China and Russia, 83% and 84% of fluoroquinolone resistant strains respectively, were observed to have gyrA mutations in the gene regions covered by the MTBDRsl assay.

Conclusions

Molecular diagnostics, specifically the Genotype MTBDRsl assay, focusing on codons 88–94 should have moderate to high sensitivity in most countries. While we did observe geographic differences in the frequencies of single gyrA mutations across countries, molecular diagnostics based on detection of all gyrA mutations demonstrated to confer resistance should have broad and global utility.  相似文献   
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