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排序方式: 共有7988条查询结果,搜索用时 15 毫秒
41.
Satoko Arai Yuka Shinohara Yasuyuki Kato Satoshi Hirano Atsuto Yoshizawa Masaaki Hojyo Nobuyuki Kobayashi Haruhito Sugiyama Koichiro Kudo 《Arerugī》2007,56(10):1293-1297
A 51-year-old man was admitted to our hospital with fever, dry cough and dyspnea. He had taken minocycline for 11 days because of urinary tract infection. Chest X-ray on admission showed diffuse reticular shadows in bilateral lung fields with bilateral pleural effusion. Cessation of minocycline led to spontaneous improvement of symptoms and radiographic findings. The lymphocyte stimulation test for minocycline with peripheral blood and pleural effusion were negative. After provocation test with minocycline, he developed fever and dry cough and bilateral ground glass opacity appeared on his chest X-ray. He was diagnosed as minocycline-induced pneumonitis and recovered rapidly following corticosteroid therapy. 相似文献
42.
It is well-known that the edge effect produced by phase contrast imaging results in the edge enhancement of x-ray images and thereby sharpens those images. It has recently been reported that phase contrast imaging using practical x-ray tubes with small focal spots has improved image sharpness as observed in the phase contrast imaging with x-ray from synchrotron radiation or micro-focus x-ray tubes. In this study, we conducted the phase contrast imaging of a plastic fiber and plant seeds using a customized mammography equipment with a 0.1 mm focal spot, and the improvement of image sharpness was evaluated in terms of spatial frequency response of the images. We observed that the image contrast of the plastic fiber was increased by edge enhancement, and, as predicted elsewhere, spectral analysis revealed that as the spatial frequencies of the x-ray images increased, so did the sharpness gained through phase contrast imaging. Thus, phase contrast imaging using a practical molybdenum anode tube with a 0.1 mm-focal spot would benefit mammography, in which the morphological detectability of small species such as microcalcifications is of great concern. And detectability of tumor-surrounded glandular tissues in dense breast would be also improved by the phase contrast imaging. 相似文献
43.
Tamiya G Shinya M Imanishi T Ikuta T Makino S Okamoto K Furugaki K Matsumoto T Mano S Ando S Nozaki Y Yukawa W Nakashige R Yamaguchi D Ishibashi H Yonekura M Nakami Y Takayama S Endo T Saruwatari T Yagura M Yoshikawa Y Fujimoto K Oka A Chiku S Linsen SE Giphart MJ Kulski JK Fukazawa T Hashimoto H Kimura M Hoshina Y Suzuki Y Hotta T Mochida J Minezaki T Komai K Shiozawa S Taniguchi A Yamanaka H Kamatani N Gojobori T Bahram S Inoko H 《Human molecular genetics》2005,14(16):2305-2321
A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases. 相似文献
44.
Yasuyuki Shibuya Hisashi Yasuda Masaki Tomatsuri Akira Mizoguchi Masatoshi Takeichi Keikichi Shimada Chizuka Ide 《Journal of neurocytology》1996,25(1):615-624
Summary The Ca2+-dependent intercellular adhesion molecule cadherin is known to be linked to the cytoskeleton by the protein catenin, an association of which appears to be important for the cell-adhesion function of cadherin. Catenin consists of three subtypes-, , and . In our previous study, N-cadherin was shown to be localized on the plasmalemma of normal and regenerating chick peripheral nerve. Thus, as N-catenin is a subtype of -catenin (which is specifically associated with N-cadherin), we investigated the immunolocalization of N-catenin in normal and regenerating chick sciatic nerve. In normal nerve, unmyelinated axons exhibited either intense or weak N-catenin immunoreactivity throughout the axoplasm, whereas myelinated axons were completely immunonegative. Regenerating axons, including those derived from parent myelinated axons, showed N-catenin immunoreactivity of variable intensities in growth cones and axon shafts. Schwann cells were invariably devoid of immunoreactivity. Thus N-catenin is not necessarily bound to the surface plasmalemma, but is distributed throughout the cytoplasm, suggesting that most N-catenin molecules are dissociated from N-cadherin. 相似文献
45.
Expression cloning of gamma interferon-inducing antigens of Mycobacterium avium subsp. paratuberculosis 下载免费PDF全文
Three recombinant proteins, Map10, Map39, and Map41, produced based on nucleotide sequences obtained from the screening of Mycobacterium avium subsp. paratuberculosis genomic library expressed in Escherichia coli significantly elicited gamma interferon production in peripheral blood mononuclear cells from infected cattle. Two of these proteins were members of the PPE protein family. 相似文献
46.
Identification of breakpoint cluster regions at 1p36.3 and 3q21 in hematologic malignancies with t(1;3)(p36;q21) 总被引:3,自引:0,他引:3
Shimizu S Suzukawa K Kodera T Nagasawa T Abe T Taniwaki M Yagasaki F Tanaka H Fujisawa S Johansson B Ahlgren T Yokota J Morishita K 《Genes, chromosomes & cancer》2000,27(3):229-238
The reciprocal translocation t(1;3)(p36;q21) is associated with myelodysplastic syndromes (MDSs) and acute myeloid leukemia (AML) characterized by trilineage dysplasia, in particular dysmegakaryocytopoiesis, and a poor prognosis. As yet no molecular genetic analyses of the t(1;3) have been reported. In four patients with t(1;3), all of whom had AML-M4, which evolved from MDS, the breakpoints at 3q21 clustered within a 60-kb region centromeric to the breakpoint of the inv(3)(q21q26), whereas the breakpoints at 1p36 clustered within a 90-kb region at 1p36.3. The presence of novel clusters in both the 3q21 and 1p36 breakpoints (BCRs) suggests a common, underlying molecular mechanism for the development of t(1;3)-positive MDS/AML. The Ribophorin I (RPN1) gene close to the BCR at 3q21 was highly expressed without gross structural changes, whereas the GR6 gene located within the BCR at 3q21 was not expressed. No other highly expressed genes were isolated in a 150-kb region at 3q21. Thus, it is likely that a gene at 1p36.3 is activated by the translocation of the 3q21 region or a gene important for transformation lies on 3q21, outside the 150-kb region. Further characterization of the BCRs at 1p36.3 and 3q21 should provide important insights into the molecular genetic mechanisms involved in the genesis of t(1;3)-positive MDS/AML. Genes Chromosomes Cancer 27:229-238, 2000. 相似文献
47.
Matsuzaki Y Sato K Sugawara K Takashita E Muraki Y Morishita T Kumagai N Suzuki S Hongo S 《Journal of clinical microbiology》2005,43(2):993-995
An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown. 相似文献
48.
Yasuyuki Suzuki Yoshio Inoue Riichir Chûj 《Macromolecular chemistry and physics.》1980,181(1):177-191
The origin of the chemical shift differences of carbons in polypeptides which accompany the helix-coil transition has been investigated by using oligopeptides, benzyloxycarbonyl-γ-ethyl-L -glutamyl-diethyl-L -glutamate and benzyloxycarbonyl-di-(γ-ethyl-L -glutamyl)-diethyl-L -glutamate, as models of the backbone of polypeptides. Structures of aggregates in deuterated chloroform were proposed for these oligopeptides on the basis of concentration dependence and temperature dependence of the chemical shifts of protons and carbons, and spin-lattice relaxation times. Antiparallel and/or parallel “in-register” structures for extended forms and “out-of-register” network of extended forms are coexisting in deuterated chloroform solution for these oligopeptides. From the shift for the carbons of the oligopeptides induced by organic acids, it was in ferred that down-field shifts are induced at α and amide carbons in polypeptides by organic acids. By comparing the induced shift of the carbons in the peptides with the chemical shift differences of the carbons in polypeptides which accompany the helix-coil transitions, it was found that the conformational changes play a predominant role in the origin of the chemical shift differences of the carbons in polypeptides which accompany the helix-coil transitions, it was found that the conformational changes play a predominnant role in the orgin of the chemical shift differences of amide, α, β, and γ carbons in polypeptides. 相似文献
49.
Furukawa Y Nakamaru K Sasaki K Fujisawa Y Minakata H Ohta S Morishita F Matsushima O Li L Alexeeva V Ellis TA Dembrow NC Jing J Sweedler JV Weiss KR Vilim FS 《Journal of neurophysiology》2003,89(6):3114-3127
We have purified a novel pentapeptide from the Aplysia nervous system using bioassay on gut contractions. The structure of the peptide is Pro-Arg-Gln-Phe-Val-amide (PRQFVa). The precursor for PRQFVa was found to code for 33 copies of PRQFVamide and four related pentapeptides. Peaks corresponding to the predicted masses of all five pentapeptides were detected in Aplysia neurons by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Northern analysis revealed that expression of the precursor is abundant in the abdominal ganglion, much less in the pedal and cerebral ganglia, and rarely seen in the buccal and pleural ganglia. PRQFVa-positive neurons, mapped by immunohistochemistry and in situ hybridization, were present in all the central ganglia. PRQFVa immunopositive processes were observed in the gut, particularly in association with the vasculature. Some arteries and other highly vascularized tissues, such as the gill and the kidney, also contain numerous PRQFVa immunopositive processes. Application of synthetic PRQFVa suppresses not only contractions of the gut but also contractions of vasculature. PRQFVa is expressed in some of the neurons within the feeding circuitry and application of synthetic PRQFVa was found to decrease the excitability of some (B4/5 and B31/32) but not all (B8) neurons of the buccal feeding circuit. Our findings suggest that PRQFVa may act as a modulator within the feeding system as well as in other systems of Aplysia. 相似文献
50.
To non-invasively determine abdominal aortic properties, a five-element lumped circuit model was adopted. The model consists
of resistance due to blood viscosity (R1), inertia of blood flow, compliances of the vessel (C1, C2), resistance of the peripheral
arteries (R2) and the impedance of the femoral arteries (termination). Patterns of the central velocity of the upper abdominal
aorta and the femoral artery are measured by pulsed Doppler echocardiography, and confours of flow volume rates are calculated.
The pressure pattern of the lower limb is recorded by a pulse wave rransducer and corrected according to sphygmomanometer
values. Contours are transformed into respective Fourier transform components. The current transfer function is described
theoretically and calculated from the acquired Fourier components. Values of every element are evaluated by the nonlinear
least squares method. In 94 subjects (17–92 years), the values of each element are estimated. R2 values are greater in the
elderly group, than in the young group and r1 (R1/cm) increased with age. This model demonstrates that vessel compliance (c1+c2 (C1+C2/cm)) decreases with age, and it is suggested that this may be a useful marker of arteriosclerosis. 相似文献