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排序方式: 共有1464条查询结果,搜索用时 15 毫秒
81.
Baririan N Chanteux H Viaene E Servais H Tulkens PM 《The Journal of antimicrobial chemotherapy》2003,51(3):651-658
Cefepime has been examined for stability, potential liberation of degradation products and compatibility with other drugs under conditions mimicking its potential use by continuous infusion in cystic fibrosis and intensive care patients (5-12% w/v solutions; temperatures from 20 to 37 degrees C; 1 h contact at 25 degrees C with other drugs frequently co-administered by intravenous route to these types of patients). Ceftazidime was used as a comparator based on a previous normative study with this antibiotic for the same indications. Based on a limit of max. 10% degradation, cefepime can be considered stable for a maximum of 24 h at 25 degrees C, but for only approximately 14 h at 30 degrees C, and for <10 h at 37 degrees C. Cefepime released so far unidentified degradation products if maintained at >30 degrees C for >12 h as shown from a marked increase in pH and from the development of a strong red-purple colour. Incompatibilities were observed with erythromycin, propofol, midazolam, phenytoin, piritramide, theophylline, nicardipine, N-acetylcysteine and a concentrated solution of dobutamine. We conclude that: (i) cefepime cannot be used safely by continuous infusion if containers are kept for more than a few hours at 37 degrees C (as will be the case for cystic fibrosis patients if using portable pumps carried under clothes); (ii) caution must be exercised in intensive care patients if the temperature and co-administration of other drugs is not kept under tight control. The nature and safety of the cefepime degradation products need to be studied further. 相似文献
82.
For many years, the detection of antigen-specific T cells has relied on indirect in vitro assays such as cytokine secretion, proliferation or chromium release assays. Things have dramatically changed during the past few years, thanks to the imagination of several investigators who have developed very elegant strategies to produce multivalent peptide/MHC complexes. One of these strategies has been to produce peptide-loaded monomeric biotinylated MHC molecules, which could be obtained as tetramers upon incubation with tetravalent streptavidin. Although this latter approach has been by far the most popular, this review focuses on other strategies which have also been successful. 相似文献
83.
The construction of hybrids between the variable fragment (Fv) of antibodies and protein MalE of Escherichia coli at the genetic level makes possible their preparation in a functional state, independently of any interaction with the antigen. We used such hybrids and a mutagenesis approach to study the recognition between antibody D1.3 and its antigen lysozyme, and its maturation. We subsequently transformed D1.3 into a reagentless fluorescent biosensor by knowledge-based design. 相似文献
84.
Siddiqui AA Phillips T Charest H Podesta RB Quinlin ML Pinkston JR Lloyd JD Pompa J Villalovos RM Paz M 《Vaccine》2003,21(21-22):2882-2889
Schistosomiasis afflicts an estimated 200 million people in 76 countries and an additional 600 million people are at risk of acquiring this infection. Even though effective anthelmintic treatment and snail eradication control programs exist, the discovery of an effective vaccine still remains the most potentially powerful means of control for this disease. We have concentrated on a vaccine candidate (large subunit of calpain or Sm-p80) because of its potential in conferring protection against challenge infection and its pivotal role in surface membrane biogenesis of schistosomes. Since surface membrane renewal is a major phenomenon employed by hemohelminths to evade host immune system; an immune response directed against Sm-p80 should make the parasite prone to immune clearance from the host by both providing a well-targeted attack and by potentially inhibiting the surface membrane biogenesis process. In the present study, we have utilized DNA immunization protocols using Sm-p80 with plasmids encoding interleukin-2 (IL-2) and interleukin-12 (IL-12). Sm-p80 by itself provided a 39% protection (P=0.0001) against challenge infection in C57BL/6 mice. This protection was increased to 57% (P=0.0001) when plasmid encoding IL-2 was co-administered with Sm-p80 DNA. Co-injection of plasmid DNA encoding IL-12 with Sm-p80 DNA yielded a protection level of 45% (P=0.0001). Statistically, the protection conferred by including IL-2 and IL-12 was significantly greater than when only the Sm-p80 was used. Sm-p80 DNA by itself elicited strong responses that includes IgG(2A) and IgG(2B) antibody isotypes. The introduction of IL-2 DNA with Sm-p80 DNA led to an increase in total IgG and IgG(2A) and IgG(2B) titres. Whereas co-administration of IL-12 DNA with Sm-p80 DNA resulted in the augmentation of only total IgG and IgG(2A). This data reinforces the potential of Sm-p80 as an excellent candidate for a schistosomiasis vaccine. 相似文献
85.
Frappaz D Chinot O Bataillard A Ben Hassel M Capelle L Chanalet S Chatel M Figarella-Branger D Guegan Y Guyotat J Khé HX Jouanneau E Keime-Guibert F Laforêt C Linassier C Loiseau H Menel P Rousmans S Sanson M Sunyach MP 《Bulletin du cancer》2003,90(10):873-886
CONTEXT: The "Standards, Options and Recommendations" (SOR) project, which started in 1993, is a collaboration between the Federation of French Cancer Centers (FNCLCC), the 20 French Regional Cancer Centers, and specialists from French public universities, general hospitals and private clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and the outcome of cancer patients. OBJECTIVE: To define clinical practice guidelines for the management of adult patients with intracranial glioma in collaboration with the Association of French-speaking Neuro-oncologists (Anocef) and the French society of neurosurgeons (SNCLF). These recommendations cover diagnosis, classification, treatment and follow-up of patients with these tumors. METHOD: The methodology is based on a literature review and critical appraisal by a multidisciplinary group of experts who define the CPGs according to the definitions of the Standards, Options and Recommendations project. Once the guidelines has been defined, the document is submitted for review by independent reviewers. RESULTS: This article is a summary version of the full document presenting the clinical practice guidelines with algorithms. The main recommendations concern the place of the surgery, radiotherapy, chemiotherapy, imagery and concomitant medical treatments in the specific treatment strategy of grade III and IV glioma, grade II glioma, gliomatosis cerebri, pilocytic astrocytoma, subependymoma, xanthoastrocytoma, intracranial ependymoma and brain stem glioma. 相似文献
86.
87.
Chanteux H Paternotte I Mingeot-Leclercq MP Brasseur R Sonveaux E Tulkens PM 《Pharmaceutical research》2003,20(4):624-631
Purpose. The purpose of this work was to examine and understand the cellular pharmacokinetics of two basic esters of ampicillin, pivaloyloxymethyl (PIVA) and phthalimidomethyl (PIMA), in comparison with lysosomotropic drugs (chloroquine, azithromycin).
Methods. Cell culture studies (J774 macrophages) were undertaken to study uptake and release kinetics and to assess the influence of concentration, pH, proton ionophore (monensin), and MRP and P-gp inhibitors (probenecid, gemfibrozil, cyclosporin A, GF 120918). Equilibrium dialysis with liposomes were performed to directly asses the extent of drug binding to bilayers. Conformational analysis modeling of the drug penetration in bilayers was conducted to rationalize the experimental observations.
Results. PIVA and PIMA showed properties in almost complete contrast with those of chloroquine and azithromycin, i.e., fast apparent accumulation and fast release at 4°C as well as at 37°C, saturation of uptake (apparent K
d 40 M), no influence of monensin, MRP, or P-gp inhibitors; tight binding to liposomes (K
d approx. 40 M); and sharp increase in calculated free energy when forced in the hydrophobic domain.
Conclusions. Although they are weak organic bases, PIVA and PIMA show none of the properties of lysosomotropic agents. We hypothesize that they remain locked onto the pericellular membrane and may never penetrate cells as such in significant amounts. 相似文献
88.
89.
Melatonin, secreted only during the night by the pineal gland, transduces the photoperiodic message to the organism. One important target for the hormone is the pars tuberalis (PT) of the adenohypophysis which displays a very high number of melatonin binding sites in mammals and is implicated in the seasonal regulation of prolactin secretion. To gain insight into the mechanism by which the melatonin signal is decoded in the PT, we studied the effect of photoperiod on the PT cells expressing the MT1 melatonin receptor in a highly photoperiodic species, the European hamster. Recently, we showed that, in the rat, the MT1 receptor mRNA is expressed in PT-specific cells characterized by their expression of beta-thyroid stimulating hormone (beta-TSH) along with the alpha-glycoprotein subunit (alpha-GSU). As the cellular composition of the PT shows variability among species, we first identified the cell type expressing the MT1 receptor in the European hamster by combining immunocytochemistry and nonradioactive in situ hybridization for the MT1 receptor mRNA. Our results show that, in the European hamster, as in the rat, the MT1 receptor is only expressed by the PT-specific-cells, beta-TSH and alpha-GSU positive. In a second step, we analysed the effects of photoperiod on the MT1 mRNA, and on beta-TSH and alpha-GSU both at the mRNA and protein levels. Our data show that, compared to long photoperiod, short photoperiod induces a dramatic decrease of MT1, beta-TSH and alpha-GSU expression. Protein levels of beta-TSH and alpha-GSU were also dramatically reduced in short photoperiod. Together, our data suggest that melatonin exerts its seasonal effects in the PT by signalling to PT specific-cells through the MT1 receptor subtype. 相似文献
90.