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11.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
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Daniel R. Einstein Blazej Neradilak Nayak Pollisar Kevin R. Minard Chris Wallis Michelle Fanucchi James P. Carson Andrew P. Kuprat Senthil Kabilan Richard E. Jacob Richard A. Corley 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(12):1628-1648
We present the results of an automated analysis of the morphometry of the pulmonary airway trees of the Sprague–Dawley rat. Our work is motivated by a need to inform lower‐dimensional mathematical models to prescribe realistic boundary conditions for multiscale hybrid models of rat lung mechanics. Silicone casts were made from three age‐matched, male Sprague–Dawley rats, immersed in a gel containing a contrast agent and subsequently imaged with magnetic resonance (MR). From a segmentation of this data, we extracted a connected graph, representing the airway centerline. Segment statistics (lengths and diameters) were derived from this graph. To validate this MR imaging/digital analysis method, airway segment measurements were compared with nearly 1,000 measurements collected by hand using an optical microscope from one of the rat lung casts. To evaluate the reproducibility of the MR imaging/digital analysis method, two lung casts were each imaged three times with randomized orientations in the MR bore. Diameters and lengths of randomly selected airways were compared among each of the repeated imaging datasets to estimate the variability. Finally, we analyzed the morphometry of the airway tree by assembling individual airway segments into structures that span multiple generations, which we call branches. We show that branches not segments are the fundamental repeating unit in the rat lung and develop simple mathematical relationships describing these structures for the entire lung. Our analysis shows that airway diameters and lengths have both a deterministic and stochastic character. Anat Rec, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
14.
Characterization of a 10- to 14-kilodalton protease-sensitive Mycobacterium tuberculosis H37Ra antigen that stimulates human gamma delta T cells. 总被引:4,自引:0,他引:4
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W H Boom K N Balaji R Nayak K Tsukaguchi K A Chervenak 《Infection and immunity》1994,62(12):5511-5518
gamma delta T-cell receptor-bearing T cells (gamma delta T cells) are readily activated by intracellular bacterial pathogens such as Mycobacterium tuberculosis. The bacterial antigens responsible for gamma delta T-cell activation remain poorly characterized. We have found that heat treatment of live M. tuberculosis bacilli released into the supernatant an antigen which stimulated human gamma delta T cells. gamma delta T-cell activation was measured by determining the increase in percentage of gamma delta T cells by flow cytometry in peripheral blood mononuclear cells stimulated with antigen and by proliferation of gamma delta T-cell lines with monocytes as antigen-presenting cells. Supernatant from heat-treated M. tuberculosis was fractionated by fast-performance liquid chromatography (FPLC) on a Superose 12 column. Maximal gamma delta T-cell activation was measured for a fraction of 10 to 14 kDa. Separation of the supernatant by preparative isoelectric focusing demonstrated peak activity at a pI of < 4.0. On two-dimensional gel electrophoresis, the 10- to 14-kDa FPLC fraction contained at least seven distinct molecules, of which two had a pI of < 4.5. Protease treatment reduced the bioactivity of the 10- to 14-kDa FPLC fraction for both resting and activated gamma delta T cells. Murine antibodies raised to the 10- to 14-kDa fraction reacted by enzyme-linked immunosorbent assay with antigens of 10 to 14 kDa in lysate of M. tuberculosis. In addition, gamma delta T cells proliferated in response to an antigen of 10 to 14 kDa present in M. tuberculosis lysate. gamma delta T-cell-stimulating antigen was not found in culture filtrate of M. tuberculosis but was associated with the bacterial pellet and lysate of M. tuberculosis. These results provide a preliminary characterization of a 10- to 14-kDa, cell-associated, heat-stable, low-pI protein antigen of M. tuberculosis which is a major stimulus for human gamma delta T cells. 相似文献
15.
Mathur SR Dahiya S Nayak A Bhatla N Singh MK 《Indian journal of pathology & microbiology》2004,47(3):333-335
We describe the clinicopathological and immunohistochemical findings in five cases of sclerosing stromal tumours of ovary and compare our findings with other reported cases of this uncommon tumour and with fibromas and thecomas which they may mimic. 相似文献
16.
The dynamics of synthesis of alpha-fetoprotein (AFP) and albumin have been studied in rat and man by immunocytochemical localization of each protein in the liver and its quantitation in serum at different periods of normal intrauterine and extrauterine life. The proteins are present only in the cytoplasm of hepatocytes. During physiologic development, an inverse relationship exists between the serum concentrations of the two proteins, the latter for each appearing to be directly related to the number of hepatocytes synthesizing it. AFP-containing cells are randomly distributed, while albumin-containing cells are more uniformly spread out. Both, however, are often preferentially located around venous channels. In the case of AFP-containing cells, the last to disappear with advancing postnatal age are seen around the hepatic veins. When both proteins are present in serum, several hepatocytes seem to syntehsize the two simultaneously, though others contain only one of them. It is unlikely that in the physiologic state different populations of hepatocytes are assigned to synthesize AFP and albumin separately. 相似文献
17.
Identification of the defects in the hemagglutinin gene of two temperature-sensitive mutants of A/WSN/33 influenza virus 总被引:4,自引:0,他引:4
S Nakajima D J Brown M Ueda K Nakajima A Sugiura A K Pattnaik D P Nayak 《Virology》1986,154(2):279-285
Two temperature-sensitive mutants of WSN influenza virus, ts-61S and ts-134, possess defects in the hemagglutinin (HA) gene. These defects are characterized as a defective intracellular transport of the HA at the nonpermissive temperature and a marked thermolability. The nucleic acid sequences of the HA gene of these two viruses, as well as a series of revertant viruses, were determined. The deduced amino acid sequences demonstrate that the HA of ts-61S varied from the wild type protein by three amino acids while that of ts-134 differed by two residues. For both mutants, analysis of revertant viruses indicated that the phenotype of transport inhibition at the nonpermissive temperature and heat lability were associated with a single amino acid change in the globular portion of the molecule. In the case of ts-61S, the critical change in the HA was the replacement of a serine residue at position 110 with that of a proline. The mutational defect in the HA of ts-134 was due to the substitution of a tyrosine residue at position 159 with that of a histidine residue. Four of five revertants of ts-134 were suppressor revertants, of which some of the compensatory changes did not restore thermostability to the HA. 相似文献
18.
Primary and revision total knee arthroplasty have become common orthopaedic procedures. The operating surgeon, at times, may be faced with a difficult surgical case due to soft tissue contractures or bone deformities. A review of multiple surgical techniques using soft tissue releases and osteotomies are presented including their potential complications. Although these techniques are aimed at the atypical operative case, the operating surgeon may utilize them for ‘routine’ exposures as well. Importance is focused on the functional integrity of the knee extensor mechanism. 相似文献
19.
20.
Frederic Shapiro Christopher Cahill George Malatantis Ramesh C. Nayak 《Anatomical record (Hoboken, N.J. : 2007)》1995,241(1):39-48
Background: The immunogold labeling technique and transmission electron microscopy were used to demonstrate the expression and position of the intermediate filament vimentin in rat osteoblast and osteocyte cell bodies and cell processes. Conventional light and transmission electron microscopic studies of bone cells demonstrated adjacent cell linkage to be mediated by osteoblast and osteocyte processes present within the canalicular system traversing the bone matrix. The cell processes were filled with densely packed filaments, many of which have been shown previously to be actin microfilaments. The appearance, however, of 10 nm diameter filaments in some cell processes and the fact that the intermediate filament vimentin has been defined in many cells of mesenchymal origin raised the possibility that some of these filaments might be vimentin. The ultrastructural colloidal gold immunochemical technique allowed for demonstration in situ of the expression of vimentin filaments plus accurate definition of their position. Methods: The studies were performed in newborn rat femoral and tibial diaphyseal cortical bone and in 1-week-old repair bone from 2.4 mm diameter defects made through the lateral cortex in 6-week-old rat femurs and tibias. The bone tissues for the immunochemical study were fixed in 1% glutaraldehyde, 4% paraformaldehyde, and 0.1 M phosphate buffer (pH 7.4) for 2 days. Decalcification was performed in 6% EDTA for 2–3 days. Infiltration involved use of Lowicryl resin K4M, and the embedding and curing processes were performed in a cryostat with temperatures ?30°C. An antivimentin monoclonal antibody was used for labeling using the postembedding technique. Effective antibody dilutions ranged from 1:10 to 1:200, with the dilutions of 1:25 and 1:100 showing the best combination of filament labeling with the least matrix background. The grids were exposed to 10 nanometer gold colloid conjugated goat anti-mouse IgM for demonstration of binding. Results: Vimentin immunolabeling was defined clearly in relation to filaments within the osteoblast and osteocyte cell body cytoplasm, throughout the entire length of the osteoblast and osteocyte cell processes, and in close relationship to the intercellular gap junctions which were present within the cell processes both close to the cell bodies and within the canaliculi well away from them. Conclusions: Immunogold labeling demonstrates the presence of the intermediate filament vimentin in osteoblast and osteocyte cell bodies and processes of rat bone. Vimentin distribution is not concentrated to specific areas, is present throughout the extent of the bodies and processes, and is seen immediately adjacent to gap junctions. © 1995 Wiley-Liss, Inc. 相似文献