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951.
Martin-McNulty B Zhang L da Cunha V Vincelette J Rutledge JC Vergona R Sullivan ME Wang YX 《Translational Research, The Journal of Laboratory and Clinical Medicine》2007,149(2):70-75
It has been demonstrated that urokinase-type plasminogen activator (uPA) plays an important role in vascular remodeling. This study was designed to determine whether uPA deficiency (KO) affects carotid artery ligation-induced vessel remodeling and the interaction with angiotensin II (Ang II). Ligation of the left common carotid artery in 6-month-old wild-type (C57 black/6J) mice for 4 weeks induced a concentric remodeling with vessel wall thickening, characterized by cell proliferation in neointima, media, and adventitia, and with lumen narrowing without a significant enlargement of overall vessel dimension. Intima lesions were characterized by alpha-actin positive smooth muscle cell (SMC) proliferation in a matrix background. No detectable presence of MAC-3 positive macrophages existed in the vascular wall. The ligation-induced vascular neointimal formation and adventitial proliferation, but not lumen narrowing and media expansion, were completely prevented in age-matched uPA-KO mice. Chronic infusion of Ang II (1.44 mg/kg per day) via a subcutaneously implanted osmotic minipump did not significantly affect the gross morphology of the nonligated carotid artery from both wild-type and uPA-KO mice, but it enhanced ligation-induced vascular remodeling. However, in the presence of Ang II, uPA deficiency had no effects on ligation-induced mophermetric change, but it partially and significantly reduced cell proliferation. These data indicate that uPA may play a critical role in ligation-induced vessel remodeling. Ang II may activate other mechanisms independent of uPA to exacerbate ligation-induced vascular remodeling. 相似文献
952.
Amanda Karolina Soares e Silva Dilênia de Oliveira Cipriano Torres Sura Wanessa Santos Rocha Fabiana Oliveira dos Santos Gomes Bruna dos Santos Silva Mariana Aragão Matos Donato Catarina Raposo Ana Célia Oliveira Santos Maria do Carmo Alves de Lima Suely Lins Galdino Ivan da Rocha Pitta José Roberto Botelho de Souza Christina Alves Peixoto 《Cardiovascular pathology》2013,22(1):81-90
BackgroundAtherosclerotic cardiovascular disease is a chronic inflammatory condition. Thiazolidinediones (TZDs) are used to enhance sensitivity to insulin and have demonstrated a protective effect over a variety of cardiovascular markers and risk factors. Controversially, the TZDs are associated with the development of heart failure. Thus, lines of research have invested in the search for new molecules in order to obtain more selective and less harmful treatment alternatives for the pathogenesis of atherosclerosis and its risk factors.MethodsAnimals were fed a diet rich in fat for 10 weeks. In the last 2 weeks, animals received either pioglitazone, LPSF/GQ-02, or LPSF/GQ-16 daily through gavage. At the end of the treatment, blood was collected for biochemical analysis and the aortas were dissected for subsequent analyses.ResultsNo changes in the blood lipid profile were found following the use of the drugs in comparison to the control. However, the new thiazolidine derivatives were more efficient in improving insulin resistance in comparison to pioglitazone and the control group. Morphometric analyses revealed that neither pioglitazone nor LPSF/GQ16 led to satisfactory effects over atherosclerosis. However, LPSF/GQ-02 led to a reduction in area of the atherosclerotic lesions. Ultrastructural analyses revealed extensive degeneration of the endothelium and an increase in apoptotic cells in the subendothelial space following the use of pioglitazone and LPSF/GQ-16. However, LPSF/GQ-02 caused minimal cell alterations in the aortic endothelium. Regarding markers, endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase 9 (MMP-9), LPSF/GQ-16, and pioglitazone exerted similar effects, increasing the expression of MMP-9, and had no effect on the expression of eNOS compared with the control group. On the other hand, LPSF/GQ-02 was effective in reducing the expression of MMP-9 and increased eNOS significantly.ConclusionsThe results suggest that the new thiazolidine derivative LPSF/GQ-02 is a promising candidate for the treatment of atherosclerosis. 相似文献
953.
Estela Kaminagakura Patrícia Luciana Batista Domingos Marize Raquel Diniz da Rosa Adriano Mota Loyola Sérgio Vitorino Cardoso Maria Cândida de Almeida Lopes Paulo Rogério Ferreti Bonan Paulo Rogério de Faria 《Annals of diagnostic pathology》2013,17(6):514-517
Calcifying cystic odontogenic tumors (CCOTs) are benign cystic lesions of odontogenic origin characterized by an ameloblastoma-like epithelium and the presence of a group of cells named ghost cells. The pattern of cytokeratin (Ck) expression on these lesions remains unclear and needs to be clarified. To this end, the expression of Ck6, Ck13, Ck14, Ck18, and Ck19 in the epithelium lining of 7 cases of CCOTs was evaluated by immunohistochemistry. For this, the epithelium lining was divided into 3 distinct regions: basal layer, suprabasal layer, and the compartment composed of ghost cells. In this study, 6 cases (85.7%) were classified as type 1 and 1 (14.3%) as type 4. All cases were negative for Ck13 and Ck18, despite the epithelial layer, as well as in the ghost cells. Ck6 was only positive in the ghost cells. Positivity for Ck14 and Ck19 was found in the basal and suprabasal layers, including the ghost cells. The results showing positivity for Ck14 and Ck19 in all of the analyzed cases reinforce CCOT as being of odontogenic origin, and the restricted expression of Ck6 in the ghost cells may be indicative that these cells suffer an altered differentiation into hair follicles in CCOTs. 相似文献
954.
A.C. da Costa I. Bendit A.C.S. de Oliveira E.G. Kallas E.C. Sabino S.S. Sanabani 《Clinical microbiology and infection》2013,19(1):E31-E43
Human parvovirus B19V (B19V) has been associated with various haematological disorders, but data on its prevalence in leukaemia are scarce. In this cross-sectional study, we investigated patients in Sao Paulo, Brazil with leukaemia to determine the molecular frequency of B19 variants and characterize the viral genetic variability by partial and complete sequencing of the coding of non-structural protein 1 (NS1)/viral capsid proteins 1 and 2 (VP1/VP2). The presence of B19V infections was investigated by PCR amplification of the viral NS1 gene fragment and confirmed by sequencing analysis. The NS1/VP1/VP2 and partially larger gene fragments of the NS1-positive samples were determined by overlapping nested PCR and direct sequencing results. The B19V NS1 was detected in 40 (16%) of 249 bone marrow samples including 12/78 (15.4%) acute lymphoblastic leukaemia, 25/155 (16.1%) acute myeloid leukaemia and 3/16 (18.7%) chronic myeloid leukaemia samples. Of the 40 participants, 25 (62.5%) were infected with genotype 1a and 15 (37.5%) with genotype 3b. The phylogenetic analysis of other regions revealed that 12/40 (30%) of the patients with leukaemia were co-infected with genotypes 1a and 3b. In addition, a new B19V intergenotypic recombinant (1a/3b) and an NS1 non-recombinant genotype 1a were detected in one patient. Our findings demonstrated a relatively high prevalence of B19V monoinfections and dual infections and provide, for the first time, evidence of inter-genotypic recombination in adults with leukaemia that may contribute to the genetic diversity of B19V and may also be a source of new emerging viral strains with future implications for diagnosis, therapy and efficient vaccine development. 相似文献
955.
956.
Flavia Corvello da Silva Francisco Maikon Corrêa de Barros Josiane Somariva Prophiro Onilda Santos da Silva Thiago Nunes Pereira Sérgio A. de Loreto Bordignon Vera Lucia Eifler-Lima Gilsane Lino von Poser 《Parasitology research》2013,112(6):2367-2371
In this study, the larvicidal activity of an enriched fraction of the major lipophilic phenolic compounds from Hypericum carinatum Griseb. (Clusiaceae) was investigated against larvae of Aedes aegypti (Diptera: Culicidae), the main vector of dengue virus in Brazil. The larval mortality rate ranged 37.33 to 72.00 % at concentrations of 66–200 μg/mL. The effect demonstrated to be dose-dependent. The lethal concentration 50 % and confidence interval were 100 and 88–111 μg/mL, respectively. The results could be attributed to the presence of cariphenone A and cariphenone B in concentrations of 1.24?±?0.04 and 0.56?±?0.01 %, respectively, determined by high-performance liquid chromatography. Besides, the results reinforce the potential of genus Hypericum as source of alternative insecticides. 相似文献
957.
L.A. Afonso W.M. Rocha F.N. Carestiato E.A. Dobao L.F. Pesca M.R.L. Passos S.M.B. Cavalcanti 《Brazilian journal of medical and biological research》2013,46(6):533-538
Cervical cancer is a major source of illness and death among women worldwide and
genital infection with oncogenic human papillomavirus (HPV) its principal cause.
There is evidence of the influence of the male factor in the development of
cervical neoplasia. Nevertheless, the pathogenic processes of HPV in men are
still poorly understood. It has been observed that different HPV types can be
found among couples. The objective of the present study was to investigate HPV
infections in female patients (n = 60 females/group) as well as in their sexual
partners and to identify the concordance of HPV genotypes among them. By using
the polymerase chain reaction, we detected a 95% prevalence of HPV DNA in women
with cervical intraepithelial neoplasia (CIN) compared to 18.3% in women with
normal cervical epithelium, with a statistically significant difference (P <
0.001). The HPV DNA prevalence was 50% in male partners of women with CIN and
16.6% in partners of healthy women. In the control group (healthy women), only 9
couples were simultaneously infected with HPV, and only 22.2% of them had the
same virus type, showing a weak agreement rate (kappa index = 0.2). Finally, we
observed that HPV DNA was present in both partners in 30 couples if the women
had CIN, and among them, 53.3% shared the same HPV type, showing moderate
agreement, with a kappa index of 0.5. This finding supports the idea of
circulation and recirculation of HPV among couples, perpetuating HPV in the
sexually active population, rather than true recurrences of latent
infections. 相似文献
958.
Genetic Analysis of PARK2 and PINK1 Genes in Brazilian Patients with Early-Onset Parkinson's Disease
Karla Cristina Vasconcelos Moura Mário Campos Junior Ana Lúcia Zuma de Rosso Denise Hack Nicaretta Jo?o Santos Pereira Delson José Silva Flávia Lima dos Santos Fabíola da Costa Rodrigues Cíntia Barros Santos-Rebou?as Márcia Mattos Gon?alves Pimentel 《Disease markers》2013,35(3):181-185
Parkinson''s disease is the second most frequent neurodegenerative disorder in the world, affecting 1-2% of individuals over the age of 65. The etiology of Parkinson''s disease is complex, with the involvement of gene-environment interactions. Although it is considered a disease of late manifestation, early-onset forms of parkinsonism contribute to 5–10% of all cases. In the present study, we screened mutations in coding regions of PARK2 and PINK1 genes in 136 unrelated Brazilian patients with early-onset Parkinson''s disease through automatic sequencing. We identified six missense variants in PARK2 gene: one known pathogenic mutation, two variants of uncertain role, and three nonpathogenic changes. No pathogenic mutation was identified in PINK1 gene, only benign polymorphisms. All putative pathogenic variants found in this study were in heterozygous state. Our data show that PARK2 point mutations are more common in Brazilian early-onset Parkinson''s disease patients (2.9%) than PINK1 missense variants (0%), corroborating other studies worldwide. 相似文献
959.
Juliana Cruz da Silva Henrique Ataide Mariz Laurindo Ferreira da Rocha Júnior Priscilla Stela Santana de Oliveira Andrea Tavares Dantas Angela Luzia Branco Pinto Duarte Ivan da Rocha Pitta Suely Lins Galdino Maira Galdino da Rocha Pitta 《Clinics (S?o Paulo, Brazil)》2013,68(6):766-771
OBJECTIVES:
Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients.METHODS:
Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients.RESULTS:
We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine.CONCLUSIONS
Our in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication. 相似文献960.
Liz Girardi Müller Camila Simonetti Pase Patrícia Reckziegel Raquel C.S. Barcelos Nardeli Boufleur Ana Cristina P. Prado Roseane Fett Jane Mara Block Maria Amália Pavanato Liliane F. Bauermann João Batista Teixeira da Rocha Marilise Escobar Burger 《Experimental and toxicologic pathology》2013,65(1-2):165-171
The hepatoprotective activity of the aqueous extract of the shells of pecan nut was investigated against ethanol-induced liver damage. This by-product of the food industry is popularly used to treat toxicological diseases. We evaluated the phytochemical properties of pecan shell aqueous extract (AE) and its in vitro and ex vivo antioxidant activity. The AE was found to have a high content of total polyphenols (192.4 ± 1.9 mg GAE/g), condensed tannins (58.4 ± 2.2 mg CE/g), and antioxidant capacity, and it inhibited Fe2+-induced lipid peroxidation (LP) in vitro. Rats chronically treated with ethanol (Et) had increased plasmatic transaminases (ALT, AST) and gamma glutamyl transpeptidase (GGT) levels (96%, 59.13% and 465.9%, respectively), which were effectively prevented (87; 41 and 383%) by the extract (1:40, w/v). In liver, ethanol consumption increased the LP (121%) and decreased such antioxidant defenses as glutathione (GSH) (33%) and superoxide dismutase (SOD) (47%) levels, causing genotoxicity in erythrocytes. Treatment with pecan shell AE prevented the development of LP (43%), GSH and SOD depletion (33% and 109%, respectively) and ethanol-induced erythrocyte genotoxicity. Catalase activity in the liver was unchanged by ethanol but was increased by the extract (47% and 73% in AE and AE + Et, respectively). Therefore, pecan shells may be an economic agent to treat liver diseases related to ethanol consumption. 相似文献