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51.
52.
Development of a high-level expression system for deuterium-labeled human serum albumin 总被引:1,自引:0,他引:1
Tomida M Kimura M Kuwata K Hayashi T Okano Y Era S 《The Japanese journal of physiology》2003,53(1):65-69
We have developed an expression system for recombinant human serum albumin (rHSA) using methylotrophic yeast Pichia pastoris Mut(+) transformants together with the multiple cross-over integration of the vector containing human serum albumin (HSA). After 86 h of methanol induction, the secreted rHSA reached levels of approximately 320 mg/l in 100% H(2)O medium and approximately 180 mg/l in 70% D(2)O/30% H(2)O (v/v) medium in a fed-batch fermenter. The structures of the obtained rHSA and plasma-derived HSA (pHSA) were virtually identical as viewed from various physicochemical techniques such as HPLC, SDS gel electrophoresis, and CD. NMR peaks of the partially deuterium (D)-labeled rHSA (DrHSA) were quite sharp compared to those of pHSA due to suppression of the intramolecular nuclear Overhauser effect, promising further structural studies of the whole HSA molecule in the solution state using the recent NMR techniques. 相似文献
53.
Therapeutic effect of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in treatment of corneal alkali burns in mice 总被引:1,自引:0,他引:1 下载免费PDF全文
Saika S Miyamoto T Yamanaka O Kato T Ohnishi Y Flanders KC Ikeda K Nakajima Y Kao WW Sato M Muragaki Y Ooshima A 《The American journal of pathology》2005,166(5):1393-1403
We evaluated the therapeutic efficacy of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in a corneal alkali burn model in mice. An alkali burn was produced with 1 N NaOH in the cornea of C57BL/6 mice under general anesthesia. SN50 (10 microg/microl) or vehicle was topically administered daily for up to 12 days. The eyes were processed for histological or immunohistochemical examination after bromodeoxyuridine labeling or for semi-quantification of cytokine mRNA. Topical SN50 suppressed nuclear factor-kappaB activation in local cells and reduced the incidence of epithelial defects/ulceration in healing corneas. Myofibroblast generation, macrophage invasion, activity of matrix metalloproteinases, basement membrane destruction, and expression of cytokines were all decreased in treated corneas compared with controls. To elucidate the role of tumor necrosis factor (TNF)-alpha in epithelial cell proliferation, we performed organ culture of mouse eyes with TNF-alpha, SN50, or an inhibitor of c-Jun N-terminal kinase (JNK) and examined cell proliferation in healing corneal epithelium in TNF-alpha-/- mice treated with SN50. An acceleration of epithelial cell proliferation by SN50 treatment was found to depend on TNF-alpha/JNK signaling. In conclusion, topical application of SN50 is effective in treating corneal alkali burns in mice. 相似文献
54.
Kazuo Tamura Yoshihiro Yamamoto Yoshifumi Saeki Jun-ichi Furuyama Joji Utsunomiya 《Human mutation》1993,2(6):478-484
Germline mutations in patients with familial adenomatous polyposis were analyzed by polymerase chain reaction (PCR) amplification of the adenomatous polyposis coli gene. PCR products from heterozygous patients for deletions of this gene formed four distinct bands on polyacrylamide gel electrophoresis. The four fragments were subsequently purified and both strands of each fragment were directly sequenced, using an automated DNA sequencer and the same primers as those for PCR amplification. It was found that the two slower migrating fragments were “bulge” heteroduplexes, while the other two were homoduplexes made up of two wild-type strands and two deletion-mutant strands, respectively. The sites of deletions in the adenomatous polyposis coli gene could be exactly determined in four of the five patients. In an attempt to identify deletion-carriers of familial adenomatous polyposis at the presymptomatic stage, a family study was also carried out, and two children were found to have the same mutations as those of their affected parents. The direct sequencing of heteroduplex fragments generated during PCR amplification is a potentially useful method for detecting mutations of not only the adenomatous polyposis coli gene but also many other genes of genetic diseases. © 1993 Wiley-Liss, Inc. 相似文献
55.
Numerical aberrations of chromosome 9 in bladder cancer. A possible prognostic marker for early tumor recurrence 总被引:3,自引:0,他引:3
Tsukamoto M Matsuyama H Oba K Yoshihiro S Takahashi M Naito K 《Cancer Genetics and Cytogenetics》2002,132(1):41-45
Bilharzial bladder cancer is one of the most common types of malignancy in both men and women in several developing countries including Egypt. It has several unique clinical, epidemiological, and histological characteristics, suggesting that it is an entity distinct from bladder cancer seen in Western countries. Genetic alterations in bilharzial-related bladder cancer have been studied infrequently, especially in the advanced stages of disease, that is, T3 and T4 classifications. The objective of this study was to extend establishing the baseline cytogenetic profile of this type of malignancy to early T1 and T2 classifications. For this purpose, fluorescence in situ hybridization was applied to interphase nuclei of frozen-stored samples with biotinylated repetitive DNA probes specific for all chromosomes to detect numerical chromosome changes in 35 patients presenting with relatively early-stage pT1 and pT2 disease. Eleven cases had squamous cell carcinoma (SCC) and 24 had transitional cell carcinoma. Six of 24 transitional cell carcinomas had diploid chromosome counts with all the probes. Numerical chromosome aberrations were detected in 18 cases (75%). In 12 cases, a loss of chromosome 9 was observed. In three cases, an additional loss of chromosome 17 was detected. One case demonstrated a loss of chromosome 10, whereas another two cases showed a gain of chromosome 7, next to a loss of chromosome 9. Loss of chromosome Y was observed in nine of the 27 male cases studied (33.3%), in which only one case showed an abnormality whereas four cases were detected next to loss of chromosome 9, and one case showed gain of chromosome 7. Five cases showed loss of chromosome 19 whereas gain of chromosome 4 was detected in two cases. Two of 11 samples of SCC had normal diploid chromosome counts with all the probes used. In four of 11 cases (36.4%) underrepresentation of chromosome 9, compared with the other chromosomes, was detected. An additional loss of chromosome 17 and gain of chromosome 7, next to loss of chromosome 9, was detected in three cases. One case showed loss of chromosome 17 as the only numerical aberration. Loss of the Y chromosome was detected in three cases of which one case had gain of chromosome 7 and one case had loss of chromosome 19. No correlation was found between any of the clinicopathologic parameters examined in this study and the presence or absence of any numerical chromosomal aberrations except for the significant association between schistosomal history and loss of Y chromosome (P=0.007). 相似文献
56.
Kazuo Umetsu Isao Yuasa Takao Yamashita Susumu Saito Tomio Yamaguchi Srinama B. Ellepola Takafumi Ishida Tsuneo Suzuki 《Journal of human genetics》1989,34(3):195-202
The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1
*
15 in Thai,ORM1
*
16 in Paraguayan,ORM2
*
21 andORM2
*
22 in Sri Lankan. 相似文献
57.
Kazuo Takayama Kanichi Yagawa Akiko Takahashi Hironori Nishio Morio Sudo Nobuyuki Sasaki Toru Yoshida Masanobu Satoh Hisaaki Abiko Akio Nunokawa Mitsuo Okazaki 《Pathology international》1969,19(4):547-562
A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation. 相似文献
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation. 相似文献
58.
Inhibition of p38MAP kinase suppresses fibrotic reaction of retinal pigment epithelial cells 总被引:3,自引:0,他引:3
59.
Kazuo Soga Takeshi Shiono Hyun Joon Kim 《Macromolecular chemistry and physics.》1993,194(12):3499-3504
A modified SiO2 was prepared by reacting SiO2 with Cl2Si(CH3)2 in toluene, on which methylaluminoxane (MAO) was supported to obtain a catalyst precursor. The mixture of the precursor and Cp2ZrCl2 (Cp: cyclopentadienyl) gave polyethylene in a high yield even by using common trialkylaluminiums as cocatalyst. Surprisingly, the MAO-free catalyst system composed of the modified SiO2 and Cp2ZrCl2 was also found to be activated by common trialkylaluminiums. 相似文献
60.
Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks. 相似文献