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1.
Management of fibroadenoma of the breast.   总被引:3,自引:0,他引:3       下载免费PDF全文
Fibroadenoma is a common cause of discrete breast lumps in young women. There is agreement that fibroadenomas can be diagnosed preoperatively with a high degree of confidence and that some of the lesions thus diagnosed will resolve, possibly obviating the need for excision. There is, however, wide disagreement over the proportion of fibroadenomas that resolve spontaneously and therefore the benefit that accrues from an expectant policy. The aim of this study was to audit the management of fibroadenomas on one unit and clarify their natural history over a 5-year period. A cohort of 70 women with 87 fibroadenomas diagnosed using a triple assessment of clinical examination, cytology and imaging (sonomammography) have been followed for a minimum of 5 years. In all, 53 of the 'fibroadenomas' have been excised. In four cases the histology revealed benign disease other than fibroadenoma; there were no neoplasms. The sensitivity of cytology and sonomammography for the diagnosis of fibroadenoma were 84% and 98% respectively. Thirty-four fibroadenomas have not been excised. Of 25 fibroadenomas that have been reassessed after at least 5 years of follow-up, 13 (52%) have reduced in size, 4 (16%) are unchanged in size and 8 (32%) have grown. No patient has developed a carcinoma at the site of the presumed fibroadenoma. This study confirms that an expectant management policy of fibroadenomas has not resulted in misdiagnosis of carcinomas. Further, since a significant proportion of fibroadenomas remain static or reduce in size over a 5-year period many women can avoid excision.  相似文献   
2.
Larger numbers of pneumococci were detected in the nasal tract compared to the lung, cervical lymph nodes, and spleen 1, 2, 4, 7, 14, and 21 days after nasal challenge with Streptococcus pneumoniae strain EF3030. In this mouse model of pneumococcal carriage, peripheral S. pneumoniae pneumococcal surface adhesin A (PsaA)-specific humoral responses (immunoglobulin G2a [IgG2a] > IgG1 = IgG2b > IgG3) were significantly higher than pneumococcal surface protein A (PspA)-specific, genetic toxoid derivative of pneumolysin (PdB)-specific, or pneumococcal surface protein C (PspC)-specific serum antibody levels. However, PspA-specific mucosal IgA antibody levels were significantly higher than those against PsaA, PdB, and PspC. In general, both PsaA- and PspA-specific lung-, cervical lymph node-, nasal tract-, and spleen-derived CD4(+) T-cell cytokine (interleukin-4, interleukin-6, granulocyte-macrophage colony-stimulating factor, gamma interferon, and tumor necrosis factor alpha) and proliferative responses were higher than those for either PspC or PdB. Taken together, these findings suggest that PsaA- and PspA-specific mucosal responses as well as systemic humoral and T helper cell cytokine responses are predominantly yet differentially induced during pneumococcal carriage.  相似文献   
3.
Journal of Public Health - This study analyzes a number of diabetic mastopathy cases in long-standing type 1 diabetes to obtain a detailed history and examination findings from these patients and...  相似文献   
4.
A new approach for the design and synthesis of cyclic N-halamine polymers having anti-bacterial activity based on a vinyl derivative of tyrosine-derived hydantoin is reported. The synthesis of N-halamine polymers generally involves the chemical modification of 5,5′-disubstituted hydantoin to introduce polymerizable vinyl moieties thereby restricting the halogen capture only on the amide nitrogen. Here we show the possibility of synthesizing vinyl monomers of N-halamine from α-amino acids wherein both the amide and imide nitrogens are available for halogen capture. Thus, a hydantoin monomer was synthesized from L-tyrosine and copolymerized with methyl methacrylate and 2-(hydroxyethyl)methacrylate, to obtain random co-polymers. The monomer and its co-polymers were characterized using NMR, IR, HRMS, GPC, DSC, EDAX and TGA analysis. Films of the co-polymers cast from 10% acetone solutions were exposed to sodium hypochlorite solution to activate the hydantoin moieties. The oxidative chlorine content of the films ranged from 0.6 to 0.9%. The activated films were exposed to both Gram positive (S. aureus) and Gram negative (E. coli) bacteria using standard protocols. Polymers having chlorine content as little as 0.6% exhibited 6 log reduction in the bacterial growth within 30 min of exposure. The method allows the halogenation of both amide and imide nitrogens and could be applied to the preparation of a number of vinyl hydantoins from many amino acids.  相似文献   
5.
Immune cell-based therapies are emerging as a promising tool to tackle malignancies, both solid tumors and selected hematological tumors. Vast experiences in literature have documented their safety and added survival benefits when such cell-based therapies are combined with the existing treatment options. Numerous methodologies of processing and in vitro expansion protocols of immune cells, such as the dendritic cells, natural killer (NK) cells, NKT cells, αβ T cells, so-called activated T lymphocytes, γδ T cells, cytotoxic T lymphocytes, and lymphokine-activated killer cells, have been reported for use in cell-based therapies. Among this handful of immune cells of significance, the NK cells stand apart from the rest for not only their direct cytotoxic ability against cancer cells but also their added advantage, which includes their capability of (i) action through both innate and adaptive immune mechanism, (ii) tackling viruses too, giving benefits in conditions where viral infections culminate in cancer, and (iii) destroying cancer stem cells, thereby preventing resistance to chemotherapy and radiotherapy. This review thoroughly analyses the sources of such NK cells, methods for expansion, and the future potentials of taking the in vitro expanded allogeneic NK cells with good cytotoxic ability as a drug for treating cancer and/or viral infection and even as a prophylactic tool for prevention of cancer after initial remission.  相似文献   
6.
7.
Next‐generation sequencing has aided characterization of genomic variation. While whole‐genome sequencing may capture all possible mutations, whole‐exome sequencing remains cost‐effective and captures most phenotype‐altering mutations. Initial strategies for exome enrichment utilized a hybridization‐based capture approach. Recently, amplicon‐based methods were designed to simplify preparation and utilize smaller DNA inputs. We evaluated two hybridization capture‐based and two amplicon‐based whole‐exome sequencing approaches, utilizing both Illumina and Ion Torrent sequencers, comparing on‐target alignment, uniformity, and variant calling. While the amplicon methods had higher on‐target rates, the hybridization capture‐based approaches demonstrated better uniformity. All methods identified many of the same single‐nucleotide variants, but each amplicon‐based method missed variants detected by the other three methods and reported additional variants discordant with all three other technologies. Many of these potential false positives or negatives appear to result from limited coverage, low variant frequency, vicinity to read starts/ends, or the need for platform‐specific variant calling algorithms. All methods demonstrated effective copy‐number variant calling when evaluated against a single‐nucleotide polymorphism array. This study illustrates some differences between whole‐exome sequencing approaches, highlights the need for selecting appropriate variant calling based on capture method, and will aid laboratories in selecting their preferred approach.  相似文献   
8.
International Journal of Diabetes in Developing Countries - Urinary progranulin is an inflammatory marker that may indicate renal damage at an early stage of diabetic nephropathy. To determine...  相似文献   
9.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - L-asparaginase (ASNase), a tetrameric enzyme, holds comprehensive applications in food industries as a...  相似文献   
10.
In this work, core–shell Fe3O4@Cu2O and Fe3O4@Cu2O–Cu nanomaterials for aerobic oxidation of benzylic alcohols are reported with 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and N-methylimidazole (NMI) as the co-catalysts. To anchor Cu2O nanoparticles around the magnetic particles under solvothermal conditions, the magnetic material Fe3O4 was modified by grafting a layer of l-lysine (l-Lys) to introduce –NH2 groups at the surface of the magnetic particles. With amine groups as the anchor, Cu(NO3)2 was used to co-precipitate the desired Cu2O by using ethylene glycol as the reducing agent. Prolonging the reaction time would lead to over-reduced forms of the magnetic materials in the presence of copper, Fe3O4@Cu2O–Cu. The nanomaterials and its precursors were fully characterized by a variety of spectroscopic techniques. In combination with both TEMPO and NMI, these materials showed excellent catalytic activities in aerobic oxidation of benzylic alcohols under ambient conditions. For most of the benzylic alcohols, the conversion into aldehydes was nearly quantitative with aldehydes as the sole product. The materials were recyclable and robust. Up to 7 repeat runs, its activity dropped less than 10%. The over-reduced materials, Fe3O4@Cu2O–Cu, exhibited slightly better performance in durability. The magnetic properties allowed easy separation after reaction by simply applying an external magnet.

Robust core–shell magnetic materials catalyse quantitatively the aerobic oxidation of a wide range of benzylic alcohols into corresponding aldehydes at room temperature showing excellent tolerance towards the substituents on the phenyl ring.  相似文献   
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