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81.
老年人的群体在不断扩大,而他们烧伤的发病率和死亡率都要比年轻人高。最近的一项病例回顾研究分析了一家烧伤中心7年来住院患者的资料,结果显示,1557位住院患者中有221位(11%)年龄在59岁以上(含59岁)。其中有97位(44%)是女性,反映出老年患者中女性比例较高。  相似文献   
82.
The factors governing in vitro basophil histamine release induced by radiocontrast material (RCM) were evaluated by the use of two RCMs (diatrizoate and metrizamide) and three structural analogs of RCM (benzoic acid, diaminobenzoic acid, and 3-acetamidobenzoic acid) in basophil histamine-release studies. Diatrizoate was chosen because it is a commonly used RCM and is routinely administered as a hypertonic drug (958 mOsm/kg or greater). Metrizamide is a newly synthesized RCM and is routinely administered in isotonic form (approximately 280 mOsm/kg). The analogs were used in hope of identifying any structure-function relationship that might exist between RCMs and the activation of a proposed basophil membrane receptor responsible for the induction of de granulation. In addition, results in a control group of normal subjects were compared with those in a group of patients who had experienced anaphylactoid reactions to intravenous RCM. Basophils from both groups were incubated with diatrizoate and metrizamide to assess their relative sensitivity to these drugs. Both metrizamide and diatrizoate induced in vitro histamine release. Therefore hypertonicity is not an absolute requirement for RCM-induced in vitro basophil de granulation. Although there was a trend far reagents without a prosthetic group at position 5 on the benzene ring (especially 3-acetamidobenzoic acid) to induce more release of histamine than reagents with such a prosthetic group, differences between these reagents did not reach statistical significance. Therefore no clearcut structure-function relationship could be demonstrated. “Reactor” subjects released significantly-larger percents of their intracellular histamine than did “nonreactors” (p < 0.05). Degranulated cells retained their ability to exclude trypan blue, an observation suggesting that RCM-induced histamine release does not involve cell death.  相似文献   
83.
Assessment of the growth fraction of non-Hodgkin's lymphomas may provide useful additional prognostic information to that obtained with conventional histological criteria. The monoclonal antibody Ki-67 has been reported to provide such information immunocytochemically in tissue biopsy specimens from lymphoma as well as other tumours. This study was undertaken to assess whether this approach could be extended to fine needle aspiration (FNA) biopsy specimens which are becoming increasingly important in the diagnosis of lymphoma. In 21 cases of non-Hodgkin's lymphoma the rate of tumour proliferation estimated by Ki-67 immunostaining of FNA material, obtained from surgically removed specimens, was compared with that obtained on tissue biopsy. The correlation between both preparations was excellent, indicating that FNA biopsy material is suitable for the immunocytochemical assessment of the growth fraction of non-Hodgkin's lymphoma.  相似文献   
84.
The 7th International Workshop on Human Leucocyte Differentiation Antigens (HLDA7) studied a number of newly characterised molecules relevant to human leucocyte differentiation and function. The HLDA organisation, which devised and continues to maintain the CD nomenclature, is responsible, under the auspices of IUIS and WHO, for the nomenclature of all leucocyte differentiation markers. The 7th Workshop redefined a number of (principally carbohydrate) molecules, and assigned CD names to approximately 80 new molecules. This update lists, in tabular form, the redefined and newly assigned names, together with antibodies, which have been confirmed under Workshop conditions as specific for the new and redefined molecules. The major features of the cellular expression patterns are summarised, and a LocusLink accession number provided to enable the reader to access more detailed information through http://www.ncbi.nlm.nih.gov/LocusLink.  相似文献   
85.
Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.  相似文献   
86.
87.
Experimental transmission of duck hepatitis B virus   总被引:22,自引:0,他引:22  
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88.
89.
Plasmacytoid T-cell lymphoma (PTL) is a rare lymphoma with unique morphologic, immunologic, and clinical features. Thus far, only three cases have been reported, each terminating in myeloid leukemia. The macrophage/monocyte rather than T-cell origin of "plasmacytoid T-cells" in reactive lymph nodes has been suggested in the past, but there has been no extensive investigation to demonstrate whether the PTLs are also of this lineage. The authors now report on a patient with PTL who had a long history of clinically stable idiopathic myelofibrosis. Immunocytochemical staining of the neoplastic plasmacytoid cells, with a large panel of monoclonal antibodies used on fresh-frozen and paraffin-embedded tissue sections, showed that the neoplastic cells expressed several macrophage/monocyte-associated markers, i.e., CD31, CD36 (thrombospondin receptor), and CD68 (KP1). Other markers of the macrophage/monocyte lineage (e.g., CD11b, CD11c, CD16) were absent. The neoplastic cells lacked B-cell-associated antigens and lacked most T-cell-associated markers, with the exception of CD2 and CD4. These findings are in close agreement with those of previous studies on normal plasmacytoid T-cells and support the macrophage/monocytic origin of PTL. Molecular hybridization studies provided additional support for the nonlymphoid origin of the plasmacytoid cells by demonstrating the absence of T-cell-receptor beta-chain and immunoglobulin heavy-chain gene rearrangements in the neoplastic cells. The results of the authors' studies indicate that "plasmacytoid T-cell lymphoma" associated with a chronic myeloproliferative disorder is of macrophage/monocyte lineage.  相似文献   
90.
Structure of the corpus luteum in the ovulatory polycystic ovary.   总被引:2,自引:0,他引:2  
BACKGROUND: Women with polycystic ovaries (PCO) have a wide spectrum of presentation from anovulation and amenorrhoea to apparently regular, ovulatory menstrual cycles. We have recently reported a subtle defect in steroidogenic function in the luteal phase in the latter and an increase in the number of degenerating corpora lutea (CL) were observed in ovulatory PCO (ovPCO) during dissection. The possibility was therefore investigated of differences in structure or degeneration in CL formed during ovulatory cycles in women with PCO. METHODS: This study compared the histology of the CL in ovPCO with that in the normal ovary. Corpora lutea were collected from nine normal ovaries (days 1-27 of the cycle) and from 13 women with ovPCO (days 5-38). RESULTS: Variations in the degree of regression, both in relation to onset of menses and between different areas within individual CL, were recorded in both groups. During development and regression no obvious differences were observed between either group apart from an apparent increase in luteal haemorrhage, which was more common and more extensive in CL from PCO. CONCLUSIONS: The findings suggest that possible luteal phase abnormalities of steroid secretion in women with ovulatory PCO are not associated with obvious morphological defects in the CL, however it is possible that the persistence of luteal structures seen in PCO was a consequence of increased luteal haemorrhage.  相似文献   
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