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51.
The effects of dietary 0.2% inositol stereoisomers on the hepatic lipids and myo-inositol (MI) status in rats fed with 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT) were investigated. Dietary MI reduced the hepatic lipids in the rats fed with DDT. Dietary D-chiro-inositol (DCI) and L-chiro-inositol (LCI) both had a promoting effect on the increase in hepatic lipids due to DDT feeding. Dietary MI enhanced the hepatic free MI level and the phosphatidylinositol/phosphatidylcholine ratio, but dietary DCI reduced the level and ratio.  相似文献   
52.
Recently, candidates for umami receptors have been identified in taste cells, but the precise transduction mechanisms of the downstream receptor remain unknown. To investigate how intracellular Ca(2+) increases in the umami transduction pathway, we measured changes in intracellular Ca(2+) levels in response to umami stimuli monosodium glutamate (MSG), IMP, and MSG + IMP in mouse taste receptor cells (TRCs) by Ca(2+) imaging. Even when extracellular Ca(2+) was absent, 1/3 of umami-responsive TRCs exhibited increased intracellular Ca(2+) levels. When intracellular Ca(2+) was depleted, half of the TRCs retained their response to umami. These results suggest that umami-responsive TRCs increase their intracellular Ca(2+) levels through two pathways: by releasing Ca(2+) from intracellular stores and by an influx of Ca(2+) from extracellular sources. We conclude that the Ca(2+) influx from extracellular source might play an important role in the synergistic effect between MSG and IMP.  相似文献   
53.
Actin-related proteins (Arps) were recently shown to contribute to the organization and regulation of chromatin structures. The nuclear functions of Arps have been investigated principally in budding yeast in which six of the ten Arp subfamilies are localized in the nucleus. In vertebrates, only two isoforms of Arp4 have so far been identified as showing localization to the nucleus. Here we show the predominant nuclear localization of another Arp subfamily, Arp6, in vertebrate cells. Vertebrate Arp6 directly interacted with heterochromatin protein 1 (HP1) orthologs and the two proteins colocalized in pericentric heterochromatin. Yeast Arp6 is involved in telomere silencing, while Drosophila Arp6 is localized in the pericentric heterochromatin. Our data strongly suggest that Arp6 has an evolutionarily conserved role in heterochromatin formation and also provide new insights into the molecular organization of heterochromatin.  相似文献   
54.
In this study, we investigated the expression of TLR5 in human corneal epithelial cells (CEC), and the functional outcome of TLR5 triggering by flagellins of pathogenic- and nonpathogenic bacteria. Flagellins derived from Pseudomonas aeruginosa, Salmonella typhimurium, Serratia marcescense or Bacillus subtilis were used. The TLR5 protein and TLR5 specific mRNA expression was evident on human CEC. In human corneal epithelium tissues, TLR5 protein was detected at the basal and wing cells of the tissues. Ocular pathogenic bacteria, namely P. aeruginosa and S. marcescense, derived flagellin induced the significantly increased level of gene activation and IL-6 and IL-8 production. In contrast, ocular nonpathogenic S. typhimurium- and B. subtilis-derived flagellin induced neither the gene activation nor the increased production of IL-6 and IL-8 in human CEC. Human CEC would respond only to flagellin derived of ocular pathogenic bacteria, but not to those derived of ocular nonpathogenic bacteria, to generate pro-inflammatory cytokines.  相似文献   
55.
AimsTo investigate the participation of KATP channels on the ischemia-reperfusion (IR)-induced apoptosis in the rat testis.Main methodsEight-week-old male Sprague–Dawley rats were divided into three groups: control and IR rats without or with cromakalim (300 μg/kg intraperitoneally), 30 min before the induction of ischemia. The right testicular artery and vein were clamped to induce ischemia in the testis. Sixty minutes after the ischemia, a 24 h period of reperfusion followed. Then, expressions of KIR6.1, KIR6.2, caspase-3, PARP, Fas, FasL, and KIR6.1 and KIR6.2 mRNAs were investigated by Western blot analyses and real-time PCR methods, respectively. Furthermore, testicular tissues were processed for histological evaluation and TUNEL staining.Key findingsExpressions of KIR6.1 protein and mRNA were more than 10-fold of those of KIR6.2 protein and mRNA in the testis. IR significantly increased the expressions of KIR6.1 protein and mRNA as well as KIR6.2 mRNA, caspase-3, and TUNEL index in the testis compared to the control. PARP expressions were significantly lower in the IR group than those of the control. Histologically, severe acute germ cell damage was observed in the IR testis. Treatment with cromakalim ameliorated these parameters compared to the non-treated IR group. There were no significant differences on Fas, FasL and protein level of KIR6.2 expressions between any of the groups.SignificanceTreatment with cromakalim has a protective effect against IR-induced testicular damage via activating KATP channels. This is the first study to give evidence for the advantageous effect of cromakalim in the germ cell-specific apoptosis induced by testicular IR.  相似文献   
56.
57.
Despite the prognostic importance of mitotic count as one of the components of the Bloom-Richardson grade, several studies have found that pathologists' agreement on the mitotic grade is fairly modest. Collecting a set of more than 4,200 candidate mitotic figures, we evaluate pathologists' agreement on individual figures, and train a computerized system for mitosis detection, comparing its performance to the classifications of three pathologists. The system's and the pathologists' classifications are based on evaluation of digital micrographs of hematoxylin and eosin stained breast tissue. On figures where the majority of pathologists agree on a classification, we compare the performance of the trained system to that of the individual pathologists. We find that the level of agreement of the pathologists ranges from slight to moderate, with strong biases, and that the system performs competitively in rating the ground truth set. This study is a step towards automatic mitosis count to accelerate a pathologist's work and improve reproducibility.  相似文献   
58.
The cyprinid tribe Labeonini (sensuRainboth, 1991) is a large group of freshwater fishes containing around 40 genera and 400 species. They are characterized by an amazing diversity of modifications to their lips and associated structures. In this study, a total of 34 genera and 142 species of putative members of this tribe, which represent most of the generic diversity and more than one third of the species diversity of the group, were sampled and sequenced for four nuclear genes and five mitochondrial genes (totaling 9465bp). Phylogenetic relationships and subdivision of this tribe were investigated and the placement and status of most genera are discussed. Partitioned maximum likelihood analyses were performed based on the nuclear dataset, mitochondrial dataset, combined dataset, and the dataset for each nuclear gene. Inclusion of the genera Paracrossochilus, Barbichthys, Thynnichthys, and Linichthys in the Labeonini was either confirmed or proposed for the first time. None of the genera Labeo, Garra, Bangana, Cirrhinus, and Crossocheilus are monophyletic. Taxonomic revisions of some genera were made: the generic names Gymnostomus Heckel, 1843, Ageneiogarra Garman, 1912 and Gonorhynchus McClelland, 1839 were revalidated; Akrokolioplax Zhang and Kottelat, 2006 becomes a junior synonym of Gonorhynchus; the species Osteochilus nashii was found to be a member of the barbin genus Osteochilichthys. Five historical hypotheses on the classification of the Labeonini were tested and rejected. We proposed to subdivide the tribe, which is strongly supported as monophyletic, into four subtribes: Labeoina, Garraina, Osteochilina, and Semilabeoina. The taxa included in each subtribe were listed and those taxa that need taxonomic revision were discussed.  相似文献   
59.
ABSTRACT: Epithelial cancers account for substantial mortality and are an important public health concern. With the need for earlier detection and treatment of these malignancies, the ability to accurately detect precancerous lesions has an increasingly important role in controlling cancer incidence and mortality. New optical technologies are capable of identifying early pathology in tissues or organs in which cancer is known to develop through stages of dysplasia, including the esophagus, colon, pancreas, liver, bladder, and cervix. These diagnostic imaging advances, together as a field known as optical endomicroscopy, are based on confocal microscopy, spectroscopy-based imaging, and optical coherence tomography (OCT), and function as "optical biopsies," enabling tissue pathology to be imaged in situ and in real time without the need to excise and process specimens as in conventional biopsy and histopathology. Optical biopsy techniques can acquire high-resolution, cross-sectional images of tissue structure on the micron scale through the use of endoscopes, catheters, laparoscopes, and needles. Since the inception of these technologies, dramatic technological advances in accuracy, speed, and functionality have been realized. The current paradigm of optical biopsy, or single-area, point-based images, is slowly shifting to more comprehensive microscopy of larger tracts of mucosa. With the development of Fourier-domain OCT, also known as optical frequency domain imaging or, more recently, volumetric laser endomicroscopy, comprehensive surveillance of the entire distal esophagus is now achievable at speeds that were not possible with conventional OCT technologies. Optical diagnostic technologies are emerging as clinically useful tools with the potential to set a new standard for real-time diagnosis. New imaging techniques enable visualization of high-resolution, cross-sectional images and offer the opportunity to guide biopsy, allowing maximal diagnostic yields and appropriate staging without the limitations and risks inherent with current random biopsy protocols. However, the ability of these techniques to achieve widespread adoption in clinical practice depends on future research designed to improve accuracy and allow real-time data transmission and storage, thereby linking pathology to the treating physician. These imaging advances are expected to eventually offer a see-and-treat paradigm, leading to improved patient care and potential cost reduction. Virtual Slide The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5372548637202968.  相似文献   
60.

Background

The ability to distinguish hepatocellular carcinoma (HCC) from metastatic carcinoma (MC) involving the liver and cholangiocarcinoma (CC) by immunohistochemistry has been limited by the lack of a reliable positive marker for hepatocellular differentiation. Arginase-1 is a marker for HCC recently described in some literature.

Aim

To examine the immunohistochemical staining of arginase-1 in cases of HCC, MC involving the liver and CC as compared to hepatocyte paraffin antigen -1 (HepPar-1) in an attempt to further define the diagnostic utility of arginase-1 in differentiating these tumors.

Materials and methods

A comparative immunohistochemical study of arginase-1 and HepPar-1expression was performed in 50 HCC cases, 38 cases of MC to the liver from varying sites, 12 cases of CC and 10 specimens of normal liver tissues. The predictive capacity of arginase-1 and HepPar-1 staining was determined using sensitivity, specificity, positive predictive value, and negative predictive value calculations.

Results

All normal liver tissues (no=10), non- neoplastic cirrhotic liver tissues adjacent to HCC (no=42) as well as those adjacent to MC (no= 9) showed diffuse and strong immunostaining for both arginase-1 and HepPar-1. Arginase-1 demonstrated positive immunoreactivity in 42 of 50 (84%) cases of HCC compared with 35 of 50 (70%) for HepPar-1. Only one of 38 (2.6%) cases of MC and one of 12 (8.3%) cases of CC showed positive immunoreactivity for arginase-1. In contrast, HepPar-1 immunoreactivity was detected in 6 of 38 (15.8%) cases of MC and in 2 of 12 (16.7%) cases of CC. Arginase -1 showed a significantly higher sensitivity for HCC diagnosis (84%) compared to HepPar -1(70%) (p=0.016). The specificity of arginase-1 for HCC diagnosis was higher (96%) than that of HepPar -1 (84%); nevertheless, this was not statistically significant (p=0.109). Howerver, the combination of both immunomarkers for the diagnosis of HCC, raised the specificity to 100%.

Conclusion

Arginase-1 immunostaining has a higher sensitivity and specificity than HepPar-1 for HCC diagnosis. Furthermore, the combined use of arginase-1 and HepPar-1 can provide a potentially promising tool to improve the accuracy in distinguishing HCC from metastatic carcinoma and cholangiocarcinoma.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9991436558072434.  相似文献   
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