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排序方式: 共有1548条查询结果,搜索用时 15 毫秒
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Kowalczyk JR Gaworczyk A Winnicka D Lejman M Babicz M 《Cancer Genetics and Cytogenetics》2003,142(1):51-55
Fluorescence in situ hybridization (FISH) using chromosome-specific DNA probes is rapidly becoming a part of clinical laboratory practice. However, as a relatively new clinical test, it is not yet standardized and for practical reasons each laboratory must establish its own criteria. For this purpose we have evaluated the specificity of a dual-color BCR/ABL translocation probe by establishing the range of BCR/ABL fusion-positive scores in a healthy donor group. The false positive rate (FPR), determined by the percent of FISH BCR/ABL fusion-positive cells found in the specimens of healthy donors, was estimated at 2.3% (mean = 1%-4%). Thus the cut-off value for false positive nuclei was set at 5%. 相似文献
3.
Thyroid-stimulating hormone and thyroid-stimulating hormone receptor structure-function relationships 总被引:9,自引:0,他引:9
This review focuses on recent advances in the structure-function relationships of thyroid-stimulating hormone (TSH) and its receptor. TSH is a member of the glycoprotein hormone family constituting a subset of the cystine-knot growth factor superfamily. TSH is produced by the pituitary thyrotrophs and released to the circulation in a pulsatile manner. It stimulates thyroid functions using specific membrane TSH receptor (TSHR) that belongs to the superfamily of G protein-coupled receptors (GPCRs). New insights into the structure-function relationships of TSH permitted better understanding of the role of specific protein and carbohydrate domains in the synthesis, bioactivity, and clearance of this hormone. Recent progress in studies on TSHR as well as studies on the other GPCRs provided new clues regarding the molecular mechanisms of receptor activation. Such advances are a result of extensive site-directed mutagenesis, peptide and antibody approaches, detailed sequence analyses, and molecular modeling as well as studies on naturally occurring gain- and loss-of-function mutations. This review integrates expanding information on TSH and TSHR structure-function relationships and summarizes current concepts on ligand-dependent and -independent TSHR activation. Special emphasis has been placed on TSH domains involved in receptor recognition, constitutive activity of TSHR, new insights into the evolution of TSH bioactivity, and the development of high-affinity TSH analogs. Such structural, physiological, pathophysiological, evolutionary, and therapeutic implications of TSH-TSHR structure-function studies are frequently discussed in relation to concomitant progress made in studies on gonadotropins and their receptors. 相似文献
4.
Rudolph C Steinemann D Von Neuhoff N Gadzicki D Ripperger T Drexler HG Mrasek K Liehr T Claussen U Emura M Schrock E Schlegelberger B 《Cancer Genetics and Cytogenetics》2004,153(2):144-150
Combining fluorescence R-banding, fluorescence in situ hybridization and spectral karyotyping allowed us to precisely define chromosomal breakpoints, gains, losses and a newly detected amplification in the human mantle cell lymphoma (MCL) cell line GRANTA-519. GRANTA-519 is characterized by the t(11;14)(q13;q32) resulting in overexpression of cyclin D1, a key player in cell cycle control. Hitherto unresolved complex rearrangements involve 1p, 1q, 3cen, 9p, 11q, 12p, 12q, 16p, 17p, and 18cen. Moreover, a 4- to 6-fold gain of sequences on 18q leads to a low-level amplification of the BCL2 gene and to an overexpression of the BCL2 protein. These results provide the basis for the identification of not only candidate oncogenes responsible for MCL in gained regions, but also for the identification of putative tumor suppressor genes in commonly deleted regions like 1p22, which would eventually enable functional studies of these genes. 相似文献
5.
Heidrun Gerr Dorothea Gadzicki Hans Kreipe Brigitte Schlegelberger Ludwig Wilkens 《Pathobiology》2006,73(6):271-279
OBJECTIVES: Fluorescence in situ hybridization (FISH) has become a useful tool to identify chromosomal aberrations in non-dividing cells. Numerous studies have compared chromosomal banding analysis (CBA) and FISH on fixed cultured bone marrow cells. However, up to now, there has been no study comparing two main sources of diagnostic material, i.e. bone marrow aspirates and trephine biopsies. We therefore analyzed these materials by FISH in comparison with CBA. METHODS: CBA revealed chromosomal aberrations in 18 patients suffering from myelodysplastic syndrome (n = 13), acute myeloid leukemia (n = 3), or chronic myeloproliferative syndrome (n = 2). FISH was performed on fixed cultured bone marrow cells, aspirates and trephine biopsies from each patient. RESULTS: Percentages of aberrant cells in the different materials correlated highly with Pearson values of 0.909 for biopsy/fixed cultured cells (p < 0.001), 0.830 for biopsy/aspirate (p < 0.001) and 0.768 for aspirate/fixed cultured cells (p < 0.001). Moreover, in bone marrow biopsies peritrabecular and central intertrabecular areas yielded very similar FISH results with a high correlation (r = 0.968, p < 0.001). FISH revealed a lower proportion of aberrant cells than CBA in 90% of the specimens. CONCLUSIONS: In summary, the different materials available for the FISH examination are comparable in sensitivity and show similar quantitative results. Therefore, the use of biopsy sections for the routine FISH examination of chromosomal abnormalities is a valid method. 相似文献
6.
Sowiska-Klencka D Klencki M Dedecjus M Lewiski A Pawlikowski M 《Endocrine pathology》2000,11(2):173-178
Nucleolar organizer regions (NORs) are segments of DNA, encoding for ribosomal RNA. They are associated with argyrophilic
proteins and, thus, they can be localized through silver staining. A correlation has been shown between the number, the size,
or the intranuclear localization of AgNORs, and the proliferative activity of cells. The aim of this study was to examine
numerous features of AgNORs in pituitary adenomas and to relate them to immunohistochemical typing of tumor. Histologic slides
from 32 pituitary tumors and one normal pituitary were silver-stained and analyzed with a computerized system for microscopic
image analysis, supported by an AgNORmeter95 program. All the tumors were also immunocyto chemically characterized. We have
found that gonadotropinomas, when compared with plurihormonal adenomas, revealed a lower proportion of nuclei with a single
AgNOR and a higher percentage of marginal dots. Recurrent adenomas, when compared with primary adenomas, showed a higher proportion
of nuclei with three AgNOR dots, a larger total area of dots in the nuclei, and a higher standard deviation of the AgNOR dot
area in the nucleus. Adenomas immunopositive for prolactin, when compared with immunonegative ones, showed a larger mean area
of the AgNOR dot, a larger area of the biggest dot in the nucleus, and a higher proportion of nuclei within a single dot.
These results suggest that the estimated parameters of AgNOR dots differ according to tumor aggressiveness and to the hormone
immunopositivity of pituitary adenomas. 相似文献
7.
Mariusz Papp Piotr Gruca Pierre-Alain Boyer Elisabeth Moca?r 《Neuropsychopharmacology》2003,28(4):694-703
Chronic mild stress (CMS), a well-validated model of depression, was used to study the effects of the melatonin agonist and selective 5-HT(2C) antagonist agomelatine (S 20098) in comparison with melatonin, imipramine, and fluoxetine. All drugs were administered either 2 h before (evening treatment) or 2 h after (morning treatment) the dark phase of the 12-h light/dark cycle. Chronic (5 weeks) evening treatment with agomelatine or melatonin (both at 10 and 50 mg/kg i.p.) dose-dependently reversed the CMS-induced reduction in sucrose consumption. The magnitude and time course of the action of both drugs was comparable to that of imipramine and fluoxetine (both at 10 mg/kg i.p.); however, melatonin was less active than agomelatine at this dose. The effect of evening administration of agomelatine and melatonin was completely inhibited by an acute injection of the MT(1)/MT(2) antagonist, S 22153 (20 mg/kg i.p.), while the antagonist had no effect in animals receiving fluoxetine or imipramine. When the drugs were administered in the morning, agomelatine caused effects similar to those observed after evening treatment (with onset of action faster than imipramine) but melatonin was ineffective. Moreover, melatonin antagonist, S 22153, did not modify the intakes in stressed animals receiving morning administration of agomelatine and in any other control and stressed groups tested in this study. These data demonstrate antidepressant-like activity of agomelatine in the rat CMS model of depression, which was independent of the time of drug administration. The efficacy of agomelatine is comparable to that of imipramine and fluoxetine, but greater than that of melatonin, which had no antidepressant-like activity after morning administration. While the evening efficacy of agomelatine can be related to its melatonin receptors agonistic properties, its morning activity, which was not inhibited by a melatonin antagonist, indicates that these receptors are certainly required, but not sufficient to sustain the agomelatine efficacy. It is therefore suggested that the antidepressant-like activity of agomelatine depends on some combination of its melatonin agonist and 5-HT(2C) antagonist properties. 相似文献
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10.
Mariusz Holtzer Rafa Dako Sylwester Piasny Micha Kubecki Dariusz Droyski Agnieszka Roczniak Mateusz Skrzyski Angelika Kmita 《Materials》2021,14(10)
The assessment of the harmfulness of moulding and core sands is mainly based on investigations of compositions of gases emitted by liquid casting alloys during the mould pouring. The results of investigations of moulding sands obtained under industrial conditions are presented in this paper. A unique research stand was designed and built for this aim. It allowed us to determine emissions of gases at individual stages of casting a mass up to 50 kg. This approach enables simulation of foundry conditions. Moulding sands bound by organic binders (phenol-formaldehyde; furan), inorganic binders and green sand, were subjected to investigations. The composition of gases that evolved during the individual stages, pouring, cooling and knocking out, was tested each time, and the contents of Polycyclic Aromatic Hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BETX) were analysed. Investigations indicated that the emission of gases from sands with inorganic binders is negligible when compared with the emission of gases from sands with organic binders. The emission of gases from green sand is placed in the middle of the scale. As an example: the sand with furan resin emitted 84 mg of BTEX (in recalculation for 1 kg of sand) while from sands with inorganic binders there was a maximum of 2.2 mg (for 1 kg of sand). In the case of sands with inorganic binders, MI and MC sands indicated comparable and very low emissions of gases from the PAHs group, at the level of 0.018 mg and 0.019 mg for 1 kg of sand, respectively. The higher emission of PAHs from MG sand is the result of its different way of hardening (a binder was of an organic character) than of sands MI and MC. 相似文献