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991.
Background: Glatiramer acetate (GA, Copaxone®) has beneficial effects on the clinical course of relapsing-remitting multiple sclerosis (RRMS). However, the exact molecular mechanisms of GA effects are only partially understood.
Objective: To characterized GA molecular effects in RRMS patients within 3 months of treatment by microarray profiling of peripheral blood mononuclear cells (PBMC).
Methods: Gene-expression profiles were determined in RRMS patients before and at 3 months after initiation of GA treatment using Affimetrix (U133A-2) microarrays containing 14,500 well-characterized human genes. Most informative genes (MIGs) of GA-induced biological convergent pathways operating in RRMS were constructed using gene functional annotation, enrichment analysis and pathway reconstruction bioinformatic softwares. Verification at the mRNA and protein level was performed by qRT-PCR and FACS.
Results: GA induced a specific gene expression molecular signature that included altered expression of 480 genes within 3 months of treatment; 262 genes were up-regulated, and 218 genes were down-regulated. The main convergent mechanisms of GA effects were related to antigen-activated apoptosis, inflammation, adhesion, and MHC class-I antigen presentation.
Conclusions: Our findings demonstrate that GA treatment induces alternations of immunomodulatory gene expression patterns that are important for suppression of disease activity already at three months of treatment and can be used as molecular markers of GA activity. 相似文献
992.
993.
P Gurevich H Ben-Hur B Sandler V Berman Y Tendler O Zinder I Zusman 《International journal of molecular medicine》1999,4(2):197-202
The role of the splenic immune system in the development of high sensitivity of p53 transgenic mice to low doses of carcinogen and vaccination was investigated immunohistochemically and morphometrically. Spleens were obtained from human p53 promoter-chloramphenicol acetyl transferase transgenic mice, grouped as follows: 1, untreated controls; 2, exposed to dimethylhydrazine (DMH); 3, and 4, vaccinated with polyclonal antibodies to soluble-53 kDa protein (s53); 5, vaccinated with monoclonal PAb DO1; 6, vaccinated with monoclonal PAb 421; 7, vaccinated with polyclonal alphaH-p53 antibody. Mice in groups 4-7 were treated with DMH after the course of vaccination. Six months later all the mice were tumor-free, but effects of the low dose carcinogen were distinct in the splenic immune system. They were mainly manifested in blast transformation: the total number of lymphocytes and lymphoblasts decreased to 56.5% of the controls. The total of lymphoid cells in the follicles (B zone) and periarterial lymph sheath (T zone) declined, reflecting moderate insufficiency of the spleen's lymphoid system. Vaccination of transgenic mice with antibodies to soluble-p53 elicited mainly a B system response, with lesser T system involvement. Only few signs of B system insufficiency were found in these mice. Vaccination of mice with different antibodies, with subsequent carcinogen treatment, caused changes in the spleen that were similar to those described for DMH alone, but varied with different anti-p53 antibodies. Vaccination with polyclonal antibodies to soluble-p53, or with monoclonal antibodies PAb DO1 or PAb 421, stimulated the splenic activity of T system, and therefore can decrease the tumorigenic effect of carcinogens. 相似文献
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995.
Margo Willems Inge Gies Dorien Van Saen 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):356-370
Klinefelter syndrome (KS) is a quite common disorder with an incidence of 1–2 in 1,000 new‐born males. Most patients are diagnosed in the light of a clinical checkup when consulting a fertility clinic with an unfulfilled child wish. Infertility in KS patients is caused by a massive germ cell loss, leading to azoospermia in more than 90% of the adult patients. Most seminiferous tubules in the adult KS testis are degenerated or hyalinized and testicular fibrosis can be observed, starting from puberty. However, focal spermatogenesis can be found in the testis of some patients. This offers the opportunity to extract spermatozoa from the testis by testicular sperm extraction (TESE). Nevertheless, TESE is only successful in about half of the KS adults seeking to father children. The reason for the germ cell loss remains unclear. To date, it is still debated whether the testicular tissue changes and the germ cell loss seen in KS is directly caused by an altered X‐linked gene expression, the altered somatic environment, or a deficiency in the germ cells. In this review, we provide an overview of the current knowledge about the germ cell loss in KS patients. 相似文献
996.
Inge Henselmans Sabrina D. Brugel Hanneke C.J.M. de Haes Kim J.A. Wolvetang Laura M. de Vries Arwen H. Pieterse Monique C.M. Baas-Thijssen Filip Y.F. de Vos Hanneke W.M. van Laarhoven Ellen M.A. Smets 《Patient education and counseling》2019,102(5):916-923
Objective
To learn how to configure a patient communication aid (PCA) to facilitate shared decision-making (SDM) about treatment for advanced cancer.Methods
The PCA consists of education about SDM, a question prompt list, and values clarification methods. Study 1. A first version was presented to 13 patients, 8 relatives and 14 bereaved relatives in interviews. Study 2. A second version was used by 18 patients in a pilot study. Patients and oncologists were interviewed, patients were surveyed, and consultations were audio-recorded.Results
Respondents reported that the aid facilitated patient control over information, raised choice awareness and promoted elaboration. Risks were identified, most importantly that the aid might upset patients. Also, some respondents reported that the PCA did not, or would not support decision making because they felt sufficiently competent, did not perceive a role for themselves, or did not perceive that the decision required elaboration.Conclusions
Opinions on the usefulness of the PCA varied. It was challenging to raise awareness about the presence of a choice, and to find a balance between comprehensive information and sensitivity.Practice implications
A future study should demonstrate whether the PCA can improve SDM, and whether this effect is stronger when oncologists receive training. 相似文献997.
The aluminothermic reduction process of manganese oxide from different slags by aluminum was investigated using pure Al and two types of industrial Al dross. Two types of MnO-containing slags were used: a synthetic highly pure CaO-MnO slag and an industrial high carbon ferromanganese slag. Mixtures of Al and slag with more Al than the stoichiometry were heated and interacted in an induction furnace up to 1873 K, yielding molten metal and slag products. The characterization of the produced metal and slag phases indicated that the complete reduction of MnO occurs via the aluminothermic process. Moreover, as the Al content in the charge was high, it also completely reduced SiO2 in the industrial ferromanganese slag. A small mass transport of Ca and Mg into the metal phase was also observed, which was shown to be affected by the slag chemistry. The obtained results indicated that the valorization of both Al dross and FeMn slag in a single process for the production of Mn, Mn-Al, and Mn-Al-Si alloys is possible. Moreover, the energy balance for the process indicated that the energy consumption of the process to produce Mn-Al alloys via the proposed process is insignificant due to the highly exothermic reactions at high temperatures. 相似文献
998.
999.
1000.
Christina Oetzmann von Sochaczewski Isabel Pintelon Inge Brouns Sofie Thys Nikolaus Deigendesch Joachim F. Kübler Jean-Pierre Timmermans Claus Petersen 《Anatomical record (Hoboken, N.J. : 2007)》2019,302(5):818-824
Vascular damage has been reported to contribute to atresia formation in several diseases including biliary atresia. This study focused on the extrahepatic biliary plexus in experimental biliary atresia. Newborn BALB/cAnNCrl-pups were infected with rhesus rotavirus within 24 hr after birth to induce experimental biliary atresia. The extrahepatic biliary plexus was examined by confocal microscopy on whole-mount preparations, scored by three independent researchers, and further evaluated at the subcellular level with transmission electron microscopy. Imaging results revealed a progressive destruction of the extrahepatic biliary vascular plexus in the course of experimental biliary atresia induced by rotavirus infection. Endothelial cell damage was already visible as cell swelling and necrosis in the first days after infection and a damaged microcirculation that rapidly deteriorated with progression of obliterative cholangiopathy, was observed in the infected mice as early as 72 hr after birth. In experimental biliary atresia, the destruction of the extrahepatic biliary vascular plexus starts already in the first days postinfection and clearly precedes the morphological symptoms of atresia. The deterioration of the vascular bed architecture continues with disease progression. Therefore, we conclude that the (ultra)structural changes in the extrahepatic biliary microvasculature occurring before the visible onset of atresia has a predictive diagnostic value and this impairment in blood supply to the extrahepatic bile duct may be an important contributing factor to the pathogenesis of acquired biliary atresia. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. Anat Rec, 302:818–824, 2019. © 2018 Wiley Periodicals, Inc. 相似文献