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1.
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.
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   
3.
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   
4.
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   
5.
6.
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   
7.
AIM:To report a patient with C282Y homozygocity,depleted body iron and intestinal atrophy caused by celiac disease (CD) who experienced resolution of the enteropathy with subsequent normalization of iron metabolism upon gluten free diet. METHODS:To obtain information on the tissue distribution and quantitative expression of proteins involved in duodenal iron trafficking,we determined the expression of divalent-metal transporter 1 (DMT1),ferroportin 1 (FP1) and transferrin receptor (TfR1) by means of immunohist-ochemistry and real-time PCR in duodenal biopsies of this patient. RESULTS:Whereas in hereditary hemochromatosis patients without CD, DMT1 expression was up-regulated leading to excessive uptake of iron, we identified a significant reduction in protein ana mRNA expression of DMT1 as a compensatory mechanism in this patient with HH and CD. CONCLUSION:Occult CD may compensate for increased DMT1 expression in a specific subset of individuals with homozygous C282Y mutations in the hemochromatosis (HFE) gene,thus contributing to the low penetrance of HH.  相似文献   
8.
AIMS: Manufacturers of pacemakers (PM) and of magnetic resonance imaging (MRI) devices state that MRI scanning of PM wearers is contraindicated. This paper tries to summarise which effects can interfere with PM, what can be hazardous, and how treatment of PM in MRI can be modified to guarantee compatibility. MATERIAL AND METHODS: All PM tested were from deceased patients. Reed contact thresholds and reactions were investigated in low magnetostatic fields and compared with those in strong magnetostatic fields. Influence of gradient fields on PM and heating due to radiofrequency (RF) pulses were estimated. Thirty Legal Medicine Departments were questioned whether deaths of PM patients during MRI are known. RESULTS: Reed contacts are influenced above 0.7 mT. In MRI fields only 28% of the PM in magnet mode remained so in all orientations. Of synchronous PM, 76% remained synchronous in all orientations. Gradient fields can influence sensing but cannot stimulate. Power density and temperature rise produced by RF fall rapidly with distance. Our question revealed six deaths. All suffered from sick-sinus-syndrome and all were not PM dependent. In three cases ventricular fibrillation was proven as the cause of death. DISCUSSION: Asynchronous pacing due to magnetostatic and gradient fields may be problematic in patients with spontaneous rhythm. To avoid them, PM triggered MRI scan restricted to refractory period is proposed. Neither inhibition of PM nor heating of the electrode poses real risks. So far, we have examined eight patients 12 times in MRI triggered mode without problems.  相似文献   
9.
In the present article, the authors want to present the results of a retrospectively evaluated consecutive series of patients with surgically treated isolated orbital floor fractures (OFF; "blow-out fractures") concerning the functional outcome after OFF and give detailed recommendations based on the clinical and radiological findings. A series of 60 patients with isolated OFF over a 5-year period needing surgically repair at the same institution were evaluated. Patient data were analysed in terms of preoperative and postoperative clinical parameters and radiological findings. The analysed parameters were type of fracture, diplopia, gaze restriction, enophthalmos, materials used for repair, surgical approach and timing of the surgical intervention. Burst type fractures were more often found than punched-out fractures. The most frequently used surgical approach was a preseptal transconjunctival approach. An overall decrease of gaze restriction (93%), diplopia (89%) and enophthalmos (86%) was observed. According to the fracture size, we used Ethisorb patches in smaller fractures and resorbable or titanium meshes or autologous bone in larger fractures in most cases. Patients who underwent surgery more than 7 days after the trauma showed better results with regard to an improvement of diplopia and motility disturbances than patients who were treated immediately. In indicated cases, the surgical repair of OFF leads to very good results if the anatomical and functional properties of the orbit and its contents are respected. The applied strategy and means presented in our study proved of value and can therefore be recommended.  相似文献   
10.
Genetic polymorphisms near IL28B are associated with spontaneous and treatment-induced clearance of hepatitis C virus (HCV), two processes that require the appropriate activation of the host immune responses. Intrahepatic inflammation is believed to mirror such activation, but its relationship with IL28B polymorphisms has yet to be fully appreciated. We analyzed the association of IL28B polymorphisms with histological and follow-up features in 2335 chronically HCV-infected Caucasian patients. Assessable phenotypes before any antiviral treatment included necroinflammatory activity (n = 1,098), fibrosis (n = 1,527), fibrosis progression rate (n = 1,312), and hepatocellular carcinoma development (n = 1,915). Associations of alleles with the phenotypes were evaluated by univariate analysis and multivariate logistic regression, accounting for all relevant covariates. The rare G allele at IL28B marker rs8099917-previously shown to be at risk of treatment failure-was associated with lower activity (P = 0.04), lower fibrosis (P = 0.02) with a trend toward lower fibrosis progression rate (P = 0.06). When stratified according to HCV genotype, most significant associations were observed in patients infected with non-1 genotypes (P = 0.003 for activity, P = 0.001 for fibrosis, and P = 0.02 for fibrosis progression rate), where the odds ratio of having necroinflammation or rapid fibrosis progression for patients with IL28B genotypes TG or GG versus TT were 0.48 (95% confidence intervals 0.30-0.78) and 0.56 (0.35-0.92), respectively. IL28B polymorphisms were not predictive of the development of hepatocellular carcinoma. CONCLUSION: In chronic hepatitis C, IL28B variants associated with poor response to interferon therapy may predict slower fibrosis progression, especially in patients infected with non-1 HCV genotypes.  相似文献   
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