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排序方式: 共有649条查询结果,搜索用时 15 毫秒
1.
Microglial Reaction in the Rat Cerebral Cortex Induced by Cortical Spreading Depression 总被引:4,自引:0,他引:4
Jochen Gehrmann Guenter Mies Petra Bonnekoh Richard Banati Takehiko Iijima Georg W. Kreutzberg Konstantin-Alexander Hossmann 《Brain pathology (Zurich, Switzerland)》1993,3(1):11-17
The response of microglial cells to cortical spreading depression (CSD) was studied in rat brain by immunocytochemistry. CSD was elicited for one hour by the topical application of 4M potassium chloride solution and the microglial reaction examined immunocytochemically after 4, 16, 24 and 72 hours. CSD was sufficient to induce a microglial reaction throughout the cortex at 24 hours. Activated microglial cells furthermore showed a striking de-novo expression of major histocompatibility complex class II antigens. In contrast, no microglial reaction was observed in the cortex of sham-operated animals. This microglial reaction in response to CSD was not associated with histologically detectable neuronal damage. These results support the view that microglial cells are extremely sensitive to changes of the brain microenvironment. Their activation may be related to changes of ion homeostasis in the brain which are not sufficient to trigger neuronal injury. 相似文献
2.
Involvement of nitric oxide in angiogenic activities of vascular endothelial growth factor isoforms 总被引:1,自引:0,他引:1
Józkowicz A Dulak J Nigisch A Funovics P Weigel G Polterauer P Huk I Malinski T 《Growth factors (Chur, Switzerland)》2004,22(1):19-28
We compared effects of vascular endothelial growth factor-121 (VEGF121) and vascular endothelial growth factor-165 (VEGF165) on generation of NO in HUVEC and the involvement of NO in VEGF121- and VEGF165-induced angiogenesis. VEGF stimulated synthesis of NO within seconds, reaching peak concentrations of 450 +/- 25 and 180 +/- 15 nmol/l for VEGF121, and VEGF165, respectively. The VEGF121 increased NO production for about 40 s while VEGF165-stimulated NO release lasted only for about 20 s. Accordingly, cGMP elevation was stronger in VEGF121- than in VEGF165-treated cells. The VEGF121 was a very weak mitogen but strong chemoattractant for HUVEC, whereas VEGF165 potently induced both cell proliferation and migration. NO appeared to be involved in the endothelial migration and morphogenesis but not in the proliferation. NO was also a permissive molecule for VEGF121- but not for VEGF165-induced capillary sprouting in spheroid culture. In conclusion, VEGF121 is a stronger stimulator of endothelial nitric oxide synthase (eNOS) activity, and angiogenic potential of VEGF121 is more reliant on NO contribution. 相似文献
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Ethical considerations in international HIV vaccine trials: summary of a consultative process conducted by the Joint United Nations Programme on HIV/AIDS (UNAIDS) 总被引:2,自引:2,他引:0 下载免费PDF全文
Research that is initiated, designed or funded by sponsor agencies based in countries with relatively high social and economic development, and conducted in countries that are relatively less developed, gives rise to many important ethical challenges. Although clinical trials of HIV vaccines began ten years ago in the US and Europe, an increasing number of trials are now being conducted or planned in other countries, including several that are considered "developing" countries. Safeguarding the rights and welfare of individuals participating as research subjects in developing countries is a priority. In September, 1997, the Joint United Nations Programme on HIV/AIDS (UNAIDS) embarked on a process of international consultation; its purpose was further to define the important ethical issues and to formulate guidance that might facilitate the ethical design and conduct of HIV vaccine trials in international contexts. This paper summarises the major outcomes of the UNAIDS consultative process. 相似文献
5.
Thomas Lenarz Hubert H Lim Guenter Reuter James F Patrick Minoo Lenarz 《Otology & neurotology》2006,27(6):838-843
The auditory midbrain implant (AMI) is a new central auditory prosthesis designed for penetrating stimulation of the human inferior colliculus. The major group of candidates for the AMI consists of neurofibromatosis type 2 (NF2) patients who develop neural deafness because of growth and/or surgical removal of bilateral acoustic neuromas. Because of the absence of a viable auditory nerve, these patients cannot benefit from cochlear implants. An alternative solution has been the auditory brainstem implant (ABI), which stimulates the cochlear nucleus. However, speech perception performance in NF2 ABI patients has been limited. The fact that the ABI is able to produce high levels of speech perception in nontumor patients (with inaccessible cochleae or posttraumatic damage to the cochlear nerve) suggests that limitations in ABI performance in NF2 patients may be associated with cochlear nucleus damage caused by the tumors or the tumor removal process. Thus, stimulation of the auditory midbrain proximal to the damaged cochlear nucleus may be a better alternative for hearing restoration in NF2 patients. We propose the central nucleus of the inferior colliculus (ICC) as the potential site. A penetrating electrode array aligned along the well-defined tonotopic gradient of the ICC should selectively activate different frequency regions, which is an important elementfor supporting good speech understanding. The goal of this article is to present the ICC as an alternative site for an auditory implant for NF2 patients and to describe the design of the first human prototype AMI. Practical considerations for implementation of the AMI will also be discussed. 相似文献
6.
Erin Gallagher Elizabeth Alvarez Lin Jin Dale Guenter Lydia Hatcher Andrea Furlan 《Canadian family physician Médecin de famille canadien》2022,68(5):e169
ObjectiveTo describe how and why patient contracts are used for the management of chronic medical conditions.Data sourcesA scoping review was conducted in the following databases: MEDLINE, Embase, AMED, PsycInfo, Cochrane Library, CINAHL, and Nursing & Allied Health. Literature from 1997 to 2017 was included.Study selectionArticles were included if they were written in English and described the implementation of a patient contract by a health care provider for the management of a chronic condition. Articles had to present an outcome as a result of using the contract or an intervention that included the contract.SynthesisOf the 7528 articles found in the original search, 76 met the inclusion criteria for the final review. Multiple study types were included. Extensive variety in contract elements, target populations, clinical settings, and cointerventions was found. Purposes for initiating contracts included behaviour change and skill development, including goal development and problem solving; altering beliefs and knowledge, including motivation and perceived self-efficacy; improving interpersonal relationships and role clarification; improving quality and process of chronic care; and altering objective and subjective health indices. How contracts were developed, implemented, and assessed was inconsistently described.ConclusionMore research is required to determine whether the use of contracts is accomplishing their intended purposes. Questions remain regarding their rationale, development, and implementation. 相似文献
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Lorena Rosik Günter Niegisch Ute Fischer Manfred Jung Wolfgang Arthur Schulz Michèle Janine Hoffmann 《Cancer biology & therapy》2014,15(6):742-757
Epigenetic modifiers such as histone deacetylases (HDACs) have come into focus as novel drug targets for cancer therapy due to their functional role in tumor progression. Since common pan-HDAC inhibitors have adverse side effects and minor anti-cancer activity against solid tumors, enzyme-specific inhibitors were developed. HDAC6 is especially well-suited for specific inhibition due to its unique domain structure and mode of action and has been suggested to provide an exceptionally suitable target for cancer therapy. However, expression and function of HDACs have been insufficiently studied in urothelial cancers (UC), a disease urgently requiring new therapeutic approaches. The present study sought to evaluate HDAC6 as a target for treatment of urothelial cancers with enzyme-specific inhibitors. We observed moderate HDAC6 overexpression in urothelial cancer tissues and a broad range of expression in urothelial cancer cell lines. In the cell lines Tubacin was the most potent inhibitor, compared with Tubastatin and ST-80, but still active only at high micromolar concentrations. HDAC6 expression levels correlated poorly with sensitivity to enzyme inhibition. Combined treatments with heat shock, HSP90 inhibition by 17-AAG, proteasome inhibition by bortezomib, or DNA-damaging agents did not result in significant synergistic effects. Experiments with siRNA-mediated knockdown further underlined that urothelial cancer cells do not critically depend on HDAC6 expression for survival. 相似文献
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10.
Hans Guenter Drexler Mira Menon Kimitaka Sagawa Eiji Tatsumi Hirofumi Koshiba Toshioki Koishi Keisuke Minato Tohru Sugimoto Masaki Saito Masuji Morita John L. Pauly Tin Han Arnold I. Freeman Harry Messmore Jun Minowada 《Annals of hematology》1986,52(2):99-109
Summary 1255 cases of leukemia-lymphoma were tested between 1972 and 1984 by multiple marker analysis. Routine leukemia phenotyping was performed using standard morphological and cytochemical techniques in combination with clinical and histo-pathological information; the main emphasis was put on immunological surface marker analysis using erythrocyte rosette assays, TdT and a large panel of poly- and monoclonal antibody tests. The 1255 cases were divided into these major types and subtypes: 349 cases of ALL and related immature T- and Burkitt-lymphomas (cALL, pre B-ALL, B-ALL and Burkitt-lymphomas, T-ALL and immature, mostly leukemic T-lymphomas, Null-ALL), 454 cases of mature T- and B-cell malignancies (T-CLL, mycosis fungoides, Sezary-syndrome, T-lymphomas, B-CLL, hairy cell leukemia, multiple myeloma, B-lymphomas), 263 cases of acute myeloid leukemias (AML, AMMoL/AMoL), 182 cases of chronic myeloid leukemias (CML in chronic phase, CMoL, CML in blast crisis), 6 cases of erythroleukemia and 1 case of megakaryoblastic leukemia. A simplified classification scheme which has been used in our laboratories is presented. Phenotyping is of diagnostic, prognostic and therapeutic relevance, most evidently for patients with ALL. Routine leukemia phenotyping should be performed with highly standardized techniques and reagents and by combining information from several fields in the multiple marker analysis. New areas of leukemia research might become very useful for the routine procedure of phenotyping.Abbreviations ALL
acute lymphoblastic leukemia
- AML
acute myeloblastic leukemia
- AMMoL
acute myelomonoblastic leukemia
- AMoL
acute monoblastic leukemia
- cALL
common ALL
- CLL
chronic lymphocytic leukemia
- CML
chronic myelocytic leukemia
- CML-BC
CML in blastic crisis
- CMoL
chronic monocytic leukemia 相似文献