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排序方式: 共有5475条查询结果,搜索用时 46 毫秒
91.
Tarta C Teixeira CR Burger MB Rosito MA Cardoso AA Gus P Damin D 《Arquivos de gastroenterologia》2000,37(2):125-128
The development of colonoscopy with image magnification has enable to study the colonic mucosa in detail and to do differential diagnosis between neoplastic and non-neoplastic lesions from the observation of pit patterns. The results are comparable to stereomicroscopy being possible to predict the histologic diagnosis. In a patient with familial adenomatous polyposis magnifying colonoscopy was performed and this method demonstrated a wide variation of benign polypoid lesions and the morphological features of early colorectal cancer. In this patient, the evaluation by image magnification, together with indigo carmin 0.4% chromoscopy, showed a wide variety of lesions in the colon and rectum: laterally spreading tumor in the cecum, with IIIL + IV pits, subpediculate polyp in the transverse colon with approximately 2.0 cm diameter and IV + V pits, flat elevated lesions IIIL type, and in the sigmoid colon IIa + IIc lesion with V type of Kudo's classification were observed. The evaluation of pit patterns of the lesions in the transverse and sigmoid colon has enable to do the endoscopic diagnosis of the lesion with submucosal invasion. 相似文献
92.
José Wellington Alves dos Santos Fabiani Palagi Machado Felipe Schaich Douglas Zaione Nascimento Tiago Teixeira Simon Luis Fernando Cibin Keli Cristina Mann Vinícius André Guerra Mateus Correa Marcos Ferreira Gazzoni Marta Pires da Rocha Melissa Daubermann Falster Ronaldo Manfredini Vassoler 《Respiratory Medicine Extra》2007,3(4):186-188
93.
94.
Laurich VM Trbovich AM O'Neill FH Houk CP Sluss PM Payne AH Donahoe PK Teixeira J 《Endocrinology》2002,143(9):3351-3360
Müllerian inhibiting substance (MIS) is produced by fetal Sertoli cells and causes regression of the Müllerian duct in male fetuses shortly after commitment of the bipotential embryonic gonad to testes differentiation. MIS is also produced by the Sertoli cells and granulosa cells of the adult gonads where it plays an important role in regulating steroidogenesis. We have previously shown that MIS can dramatically reduce testosterone synthesis in Leydig cells by inhibiting the expression of cytochrome P450 17alpha-hydroxylase/C(17-20) lyase (Cyp17) mRNA in vitro and in vivo. To characterize the signal transduction pathway used by MIS to control expression of endogenous Cyp17 in a mouse Leydig cell line, we demonstrate that MIS inhibits both LH- and cAMP-induced expression of Cyp17 at concentrations as low as 3.5 nM and for as long as 18 h. The induction of steroidogenic acute regulatory protein (StAR) mRNA by cAMP, however, was slightly increased by addition of MIS. Protein kinase A (PKA) inhibition with H-89 blocked Cyp17 mRNA induction, suggesting that MIS interferes with the PKA signal transduction pathway. Inhibition of Cyp17 induction was not seen with added U0126, and wortmannin inhibited the induction incompletely. In addition, phosphorylation of the cAMP responsive element binding protein (CREB) was not detected following 50 micro M cAMP exposure, a concentration sufficient for Cyp17 mRNA induction. Moreover, CREB phosphorylation, which was observed with addition of 500 micro M cAMP, was not inhibited by coincubation with MIS. Taken together, these results suggest that cAMP induces expression of Cyp17 by a PKA-mediated mechanism and that this induction, which is inhibited by MIS signal transduction, does not require CREB activity, and is distinct from that used to induce steroidogenic acute regulatory protein expression. 相似文献
95.
96.
Izabela Guimar?es Barbosa Natália Pessoa Rocha Frankcinéia Assis érica Leandro Marciano Vieira Jair C Soares Moises Evandro Bauer Ant?nio Lúcio Teixeira 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(1)
Background:
This study tested the hypothesis that the low-grade inflammation presented in patients with bipolar disorder (BD) is associated with expansion of activated T cells, and this activated state may be due to a lack of peripheral regulatory cells.Methods:
Specifically, we investigated the distribution of monocytes and lymphocyte subsets, and investigated Th1/Th2/Th17 cytokines in plasma by flow cytometry. Twenty-one BD type I patients and 21 age- and sex-matched controls were recruited for this study.Results:
BD patients had increased proportions of monocytes (CD14+). Regarding lymphocyte populations, BD patients presented reduced proportions of T cells (CD3+) and cytotoxic T cells (CD3+CD8+). BD patients also exhibited a higher percentage of activated T CD4+CD25+ cells, and a lower percentage of IL-10 expressing Treg cells.Conclusions:
Our data shed some light into the underlying mechanisms involved with the chronic low-grade inflammatory profile described in BD patients. 相似文献97.
Luduvico Karina Pereira Spohr Luiza de Aguiar Mayara Sandrielly Soares Teixeira Fernanda Cardoso Bona Natália Pontes de Mello Julia Eisenhardt Spanevello Roselia Maria Stefanello Francieli Moro 《Metabolic brain disease》2022,37(6):2133-2140
Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This... 相似文献
98.
João Dallyson Sousa de Almeida Aristófanes Corrêa Silva Jorge Antonio Meireles Teixeira Anselmo Cardoso Paiva Marcelo Gattass 《Journal of digital imaging》2015,28(4):462-473
Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist. 相似文献
99.
Joana Vieira Carla Pinto Mariana Afonso Maria do Bom Sucesso Paula Lopes Manuela Pinheiro Isabel Veiga Rui Henrique Manuel R Teixeira 《European journal of human genetics : EJHG》2015,23(5):715-718
Fibromatous soft tissue lesions, namely desmoid-type fibromatosis and Gardner fibroma, may occur sporadically or as a result of inherited predisposition (as part of familial adenomatous polyposis, FAP). Whereas desmoid-type fibromatosis often present β-catenin overexpression (by activating CTNNB1 somatic variants or APC biallelic inactivation), the pathogenetic mechanisms in Gardner fibroma are unknown. We characterized in detail Gardner fibromas diagnosed in two infants to evaluate their role as sentinel lesions of previously unrecognized FAP. In the first infant we found a 5q deletion including APC in the tumor and the novel APC variant c.4687dup in constitutional DNA. In the second infant we found the c.5826_5829del and c.1678A>T APC variants in constitutional and tumor DNA, respectively. None of the constitutional APC variants occurred de novo and both tumors showed nuclear staining for β-catenin and no CTNNB1 variants. We present the first comprehensive characterization of the pathogenetic mechanisms of Gardner fibroma, which may be a sentinel lesion of previously unrecognized FAP families. 相似文献
100.
Thiago Magalh?es da Silva M R Sandhya Rani Gustavo Nunes de Oliveira Costa Maria A Figueiredo Paulo S Melo Jo?o F Nascimento Neil D Molyneaux Maurício L Barreto Mitermayer G Reis M Glória Teixeira Ronald E Blanton 《European journal of human genetics : EJHG》2015,23(7):984-989
The degree of admixture in Brazil between historically isolated populations is complex and geographically variable. Studies differ as to what the genetic and phenotypic consequences of this mixing have been. In Northeastern Brazil, we enrolled 522 residents of Salvador and 620 of Fortaleza whose distributions of self-declared color were comparable to those in the national census. Using the program Structure and principal components analysis there was a clear correlation between biogeographic ancestry and categories of skin color. This correlation with African ancestry was stronger in Salvador (r=0.585; P<0.001) than in Fortaleza (r=0.236; P<0.001). In Fortaleza, although self-declared blacks had a greater proportion of European ancestry, they had more African ancestry than the other categories. When the populations were analyzed without pseudoancestors, as in some studies, the relationship of ‘race'' to genetic ancestry tended to diffuse or disappear. The inclusion of different African populations also influenced ancestry estimates. The percentage of unlinked ancestry informative markers in linkage disequilibrium, a measure of population structure, was 3–5 times higher in both Brazilian populations than expected by chance. We propose that certain methods, ascertainment bias and population history of the specific populations surveyed can result in failure to demonstrate a correlation between skin color and genetic ancestry. Population structure in Brazil has important implications for genetic studies, but genetic ancestry is irrelevant for how individuals are treated in society, their health, their income or their inclusion. These track more closely with perceived skin color than genetic ancestry. 相似文献