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11.
The pathways conferring immunity to human filariases are not well known, in part because human-pathogenic filariae do not complete a full life cycle in laboratory mice. We have used the only fully permissive infection of mice with filariae, i.e., infection of BALB/c mice with the rodent filarial nematode Litomosoides sigmodontis. Our previous results showed that worm development is inversely correlated with Th2 cytokine production and eosinophilia. The scope of the present study was to directly elucidate the role of interleukin-5 (IL-5) and eosinophils in controlling the development of L. sigmodontis after vaccination and in primary infection. BALB/c mice immunized with irradiated third-stage larvae (L3) were confirmed to have elevated IL-5 levels as well as high subcutaneous eosinophilia and to attack and reduce incoming larvae within the first 2 days, resulting in 70% reduction of worm load. Treatment of vaccinated mice with anti-IL-5 antibody (TRFK-5) suppressed both blood and tissue eosinophilia and completely abolished protection. This demonstrates, for the first time in a fully permissive filarial infection, that IL-5 is essential for protection induced by irradiated L3 larvae. In contrast, in primary-infected mice, anti-IL-5 treatment did not modify filarial infection within the 1st month, most likely because during primary infection IL-5-dependent mechanisms such as subcutaneous eosinophilia are induced too late to disturb worm establishment. However, there is a role for IL-5 late in primary infection where neutrophil-dependent worm encapsulation is also under the control of IL-5. Received: 30 March 2000  相似文献   
12.
Protective immunity in mice infected with Toxoplasma gondii is mainly mediated by NK cells, CD4 and CD8 T cells, and type 1 cytokines, such as gamma interferon (IFN-gamma). To clarify the roles of NK cells and IFN-gamma in protection against primary congenital toxoplasmosis, we used recombination activating gene 2 knockout (RAG-2(-/-)) mice, which lack T and B lymphocytes, in comparison with the wild-type BALB/c model. RAG-2(-/-) mice had a significantly lower risk of fetal toxoplasmosis than BALB/c mice (25 versus 63.9%; P = 0.003). This protection was associated with an increased number of maternal NK cells, IFN-gamma secretion by spleen cells, and decreased parasitemia. In the RAG-2(-/-) mice, NK cell depletion increased both the rate of fetal infection, to 56.5% (P = 0.02), and the blood parasite burden. Conversely, in the BALB/c mice, this treatment did not modify maternofetal transmission or the blood parasite burden. Neutralization of IFN-gamma in both infected RAG-2(-/-) and BALB/c mice decreased congenital Toxoplasma transmission, contrasting with an exacerbation of maternal infection. These data suggest that a partially protective immunity against congenital toxoplasmosis is achieved due to the increased number of NK cells in RAG-2(-/-) mice. However, it seems that IFN-gamma enhances, directly or indirectly, the transplacental transmission.  相似文献   
13.
BACKGROUND: Translocation of phosphatidylserine (PS) from the inner to the outer leaflet of the plasma membrane is a modification of the lipid architecture occurring in sperm. This is one of the earliest signs of apoptosis that can be monitored by the calcium-dependent binding of annexin V. METHODS AND RESULTS: Flow cytometric analysis of annexin V binding was performed. Calcium ionophore A23187 led to a significant increase in the proportion of living sperm with PS exposure: 7.3 3.2% of cells in the untreated ejaculate versus 47.5 5.6% of cells after 1 h of incubation with A23187. Conversely, diminution of mitochondrial membrane potential [DiOC6(3)/propidium iodide (PI) assay], caspase activation [fluorescein isothiocyanate (FITC)-Val-Ala-Asp-fluoromethylketone (VAD-FMK)/PI assay], increased plasma membrane permeability (Yo-Pro-1/PI assay) and increased DNA fragmentation [TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling assay], which are among the main signs of apoptosis, were not observed in sperm, even after 4 h of incubation with A23187. However, A23187 significantly increased the proportion of sperm with plasma membrane scrambling and with a reacted acrosome, as detected with the merocyanine 540 probe (M540) and the monoclonal anti-human CD46-PE antibody respectively. CONCLUSIONS: Our results suggest that PS exposure in human sperm, as induced by A23187, is mainly related to the acrosome reaction rather than to apoptosis.  相似文献   
14.
Cellular HIV-1 DNA level was sequentially measured by quantitative polymerase chain reaction in 141 patients not previously treated with highly active antiretroviral therapy (HAART), who were enrolled in a 72-week randomized trial (ANRS 081 "Trianon") comparing 2 regimens, including 3 drugs from 2 classes (indinavir + stavudine + lamivudine, group 1) or 3 classes (indinavir + stavudine + nevirapine, group 2). The median decrease from baseline to week 72 in cellular HIV-1 DNA level was not significantly different between the 2 groups (0.54 and 0.45 log10 copies/10 peripheral blood mononuclear cells [PBMCs] in groups 1 and 2, respectively), whereas a higher proportion of patients maintained a plasma HIV-1 RNA level less than 20 copies/mL at week 72 in group 1 than in group 2 (79% and 52%; P = 0.0009). Furthermore, the difference in cellular HIV-1 DNA decrease from baseline to week 72 between patients who achieved a plasma HIV-1 RNA level less than 20 copies/mL at week 72 and those who did not was not statistically significant (0.54 and 0.45 log10 copies/10 PBMCs, respectively; P = 0.14). The decay in cellular HIV-1 DNA from baseline to week 72 was higher in antiretroviral-naive patients than in pretreated patients (0.55 and 0.23 log10 copies/10 PBMCs, respectively; P = 0.0008). The cellular HIV-1 DNA level change under therapy was best fitted to a 2-phase decay model with a junction point at week 16, from which its half-life was estimated at 18 weeks during the initial phase and at 104 weeks thereafter. In conclusion, the changes under therapy in cellular HIV-1 DNA level, which were mostly coincident to those of plasma HIV-1 RNA, did not add significant information to the comparison of the viral efficacy of the 2 studied regimens.  相似文献   
15.
Real-time PCR was compared to Amplified Mycobacterium tuberculosis Direct Test (AMTDII) for 100 clinical specimens. The overall sensitivities of the real-time PCR method and AMTDII were similar for respiratory and nonrespiratory specimens. However, real-time PCR seemed to be less susceptible to amplification inhibitors than AMTDII.  相似文献   
16.
Neuroendocrine differentiation has been reported in both in situ and infiltrating breast cancers. The prognostic significance of neuroendocrine differentiation in mammary carcinoma is unclear. We report a case of infiltrating ductal carcinoma in which there was a morphologically conventional-appearing infiltrating ductal component admixed with nests of cells that resembled a carcinoid tumor and initially mimicked the appearance of intraductal carcinoma. Immunohistochemical stains for synaptophysin and chromogranin demonstrated diffuse, strong positivity uniformly throughout the tumor, even in the more conventional-appearing areas. Electron microscopic examination of tissue retrieved from paraffin blocks was attempted unsuccessfully. We concluded that this was an infiltrating ductal carcinoma with morphologic and immunohistochemical evidence of neuroendocrine differentiation. The case is discussed with a review of the literature and a discussion of nomenclature for tumors of the breast showing variable degrees of neuroendocrine differentiation.  相似文献   
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18.
IntroductionThere is general agreement that it is possible to have an orgasm thru the direct simulation of the external clitoris. In contrast, the possibility of achieving climax during penetration has been controversial.MethodsSix scientists with different experimental evidence debate the existence of the vaginally activated orgasm (VAO).Main Outcome MeasureTo give reader of The Journal of Sexual Medicine sufficient data to form her/his own opinion on an important topic of female sexuality.ResultsExpert #1, the Controversy's section Editor, together with Expert #2, reviewed data from the literature demonstrating the anatomical possibility for the VAO. Expert #3 presents validating women's reports of pleasurable sexual responses and adaptive significance of the VAO. Echographic dynamic evidence induced Expert # 4 to describe one single orgasm, obtained from stimulation of either the external or internal clitoris, during penetration. Expert #5 reviewed his elegant experiments showing the uniquely different sensory responses to clitoral, vaginal, and cervical stimulation. Finally, the last Expert presented findings on the psychological scenario behind VAO.ConclusionThe assumption that women may experience only the clitoral, external orgasm is not based on the best available scientific evidence. Jannini EA, Rubio‐Casillas A, Whipple B, Buisson O, Komisaruk BR, and Brody S. Female orgasm(s): one, two, several. J Sex Med 2012;9:956–965.  相似文献   
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There is increasingly a call for clinical relevance in the teaching of biomedical sciences within all health care courses. However, this presupposes that there is a clear understanding of what can be considered core material within the curricula. To date, the anatomical sciences have been relatively poorly served by the development of core syllabuses, particularly for specialized core syllabuses such as neuroanatomy. One of the aims of the International Federation of Associations of Anatomists (IFAA) and of the European Federation for Experimental Morphology (EFEM) is to formulate, on an international scale, core syllabuses for all branches of the anatomical sciences using Delphi Panels consisting of anatomists, scientists, and clinicians to initially evaluate syllabus content. In this article, the findings of a Delphi Panel for neuroanatomy are provided. These findings will subsequently be published on the IFAA website to enable anatomical (and other cognate learned) societies and individual anatomists, clinicians, and students to freely comment upon, and elaborate and amend, the syllabuses. The aim is to set internationally recognized standards and thus to provide guidelines concerning neuroanatomical knowledge when engaged in course development. Clin. Anat. 28:706–716, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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