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BACKGROUND: Chronic anal fissure is a lineal ulcer of the lower part of the anal canal. It is a painful condition characterized by postdefecational pain and bleeding. It is associated with internal anal sphincter spasm. The relief of internal anal sphincter spasm is the key for providing fissure healing. Gold standard in the treatment of chronic anal fissure is partial lateral internal anal sphincterotomy. METHODS: Sixty patients with chronic anal fissure were randomly assigned into two groups treated either by surgical sphincterotomy or injections of botulinum toxin into internal anal sphincter. Manometric measurements were performed before and three months after treatment. Follow up period was six months. The aim of the study was to compare results between these two groups. RESULTS: Both methods efficiently reduced resting anal pressure and successfully healed chronic anal fissure. CONCLUSION: Surgical and biologic sphincterotomy are almost equally effective in the treatment of chronic anal fissure. Injecting botulinum toxin into internal anal sphincter is a safe, easy to apply and effective method in the management of anal fissure.  相似文献   
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The charging behavior of water‐soluble cellulose‐4‐[N‐methylamino]butyrate hydrochloride (CMABH) with different degree of substitution (DS) is investigated by polyelectrolyte titration at different pH values. Samples of high DS (0.92) and low DS (0.31) exhibit a decrease in positively charged groups from pH 2 (3.9 and 1.9 mmol g?1) to pH 9 (0.81 and 0.65 mmol g?1) due to the deprotonation of the ammonium groups. The stability of the ester linkage of CMABH is examined as a function of pH value and storage time (up to 28 d). A hydrolysis of the ester moiety is evident after 2 h at pH 8, which is also proved by ATR‐FTIR‐ and Raman spectroscopy.  相似文献   
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The accessibility of functional groups of 3,6‐O‐chitosansulfate in water is studied using conductometric and polyelectrolyte titration techniques. These studies reveal the good accessibility of protonated amino groups following conductometric titrations and pH dependency on the accessibility of negatively charged sulfate groups following polyelectrolyte titrations. In addition, the influence of negatively charged sulfate groups, introduced onto polymer backbone by synthesis, is analyzed regarding the well‐known antimicrobial activities of chitosan. The assessment of the mortality rates of Gram‐negative, Gram‐positive bacteria, and pathogenic fungi reveal that sulfate groups in chitosan lead to a tremendous loss in antimicrobial activity compared with nonmodified chitosan.  相似文献   
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The prognostic potential of apparent diffusion coefficient (ADC) mapping was studied as complemented by high-resolution 3D T(1)-weighted MRI in the assessment of dentin-pulp complex response to caries. Twenty-six extracted human teeth, with or without caries lesions of different grades in accord with the International Caries Detection and Assessment System (ICDAS), were analyzed by high-resolution MRI at 2.35 T. A signal rise in demineralized hard dental tissues in high-resolution T(1)-weighted MR images enabled assessment of the demineralization depth over the whole range of ICDAS scores. ADC maps of the teeth were calculated from corresponding diffusion-weighted images of four different b values: 0, 132, 317, 635 s/mm(2). These maps enabled reliable differentiation between intact (ADC > 1.0·10(-9) m(2)/s) and affected (ADC < 1.0·10(-9) m(2)/s) regions of dental pulp. Linear regression analyses of demineralization depth in relation to ICDAS score and then also to average ADC of dental pulp showed that a demineralization depth increase of one millimeter corresponds to an ICDAS score increase of 1.2 and an average ADC decrease of 0.07·10(-9) m(2)/s. Results of the study indicate that the average ADC value of dental pulp could be used as a potential marker to assess tissue response to caries comparable to that of ICDAS scoring.  相似文献   
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Since 2000, GAVI provided essential support for an unprecedented increase in the use of hepatitis B (HepB) and Haemophilus influenzae (Hib) containing vaccines in resource poor countries. This increase was supported with significant funding from international donors, intended to be time-limited. To assess the sustainability of this important expansion of the global access to vaccines, we reviewed supply chains, financial resources for procurement and decision-making in countries that introduced hepatitis B or Hib vaccines with GAVI support. During the period studied, the types of vaccine products supplied fluctuated rapidly in relationship with the number of suppliers and availability of more combination products. The price of the cheaper vaccines decreased while that of pentavalent DTwP-HepB-Hib remained stable. In average, vaccine introduction was associated with an increase of national programs budget, with new vaccines representing more than half of that increase, while the part of GAVI contributions to the budget went from 25% to 46%. Less than 20% of the vaccine introductions were decided by a national advisory body. Strengthening supply chains, adjusting funding schemes and increasing national ownership will be key to the sustained use of hepatitis B and Hib vaccines and the eventual addition of other important vaccines where they are the most needed.  相似文献   
57.
PET Imaging with [11C]-choline has become a useful tool in the investigation of prostate cancer, with as main application the assessment of previously treated patients presenting with rising PSA and negative conventional imaging procedures. In this case report we describe [11C]-choline PET/CT findings in a patient with a locally advanced cancer, which could be successfully identified thanks to the early image acquisition and the delayed urinary excretion of the carbon-11 labeled tracer.  相似文献   
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Purpose: Ultraviolet (UV) radiation-induced apoptosis enabled us to study the mechanism of DNA damage and to investigate how cells avoid consequences of damaged DNA. Cells with extensive DNA damage activate extrinsic and intrinsic pathways of apoptosis. The extrinsic pathway is coupled to a FAS-associated protein with death domain (FADD), an adaptor protein molecule necessary for mediating apoptotic signals through the cell.

Materials and methods: Viability and apoptosis of wild-type and FADD-deficient mouse embryonic fibroblasts were investigated 1, 3, 24 and 48?h after exposure to three doses (50, 75 and 300 J/m2) of UVC radiation. Morphological changes were observed using DNA binding dyes (Hoechst and propidium iodide) while biochemical changes were monitored using immunodetection of the poly (ADP-ribose) polymerase (PARP) protein cleavage and caspase-3 activity assay.

Results: Results showed that the difference in cell death response between wild-type and FADD-deficient cells depended on dose and incubation time after exposure to UVC radiation. FADD-deficient cells are more sensitive to UVC radiation. Even though FADD-deficient cells lack an adapter protein of apoptotic extrinsic pathway, higher doses of UVC triggered their apoptotic response, while wild-type cells die mainly due to necrosis. A different pattern of caspase 3 activity and PARP cleavage was observed 24?h after radiation between two cell lines confirming higher apoptotic response in FADD-deficient cells.

Conclusions: Wild-type cells can execute apoptosis via both, the mitochondrial and the receptor-mediated pathway whereas FADD-deficient cells can only activate the intrinsic pathway. There is a difference in UVC radiation response between two cell lines indicating the role of FADD in the selection of cell death modality.  相似文献   
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