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排序方式: 共有5433条查询结果,搜索用时 15 毫秒
81.
Christiane Mariotini-Moura Matheus Silva e Bastos Felipe Freitas de Castro Mellina Lanna Trindade Raphael de Souza Vasconcellos Myrian Augusta Araújo Neves-do-Valle Bernardo Pereira Moreira Ramon de Freitas Santos Claudia Miranda de Oliveira Luana Celina Seraphim Cunha Xênia Macedo Souto Gustavo Costa Bressan Abelardo Silva-Júnior Munira Muhammad Abdel Baqui Maria Terezinha Bahia Márcia Rogéria de Almeida José Roberto Meyer-Fernandes Juliana Lopes Rangel Fietto 《Acta tropica》2014
Previous work has suggested that Trypanosoma cruzi diphosphohydrolase 1 (TcNTPDase-1) may be involved in the infection of mammalian cells and serve as a potential target for rational drug design. In this work, we produced recombinant TcNTPDase-1 and evaluated its nucleotidase activity, cellular localization and role in parasite adhesion to mammalian host cells. TcNTPDase-1 was able to utilize a broad range of triphosphate and diphosphate nucleosides. The enzyme's Km for ATP (0.096 mM) suggested a capability to influence the host's ATP-dependent purinergic signaling. The use of specific polyclonal antibodies allowed us to confirm the presence of TcNTPDase-1 at the surface of parasites by confocal and electron microscopy. In addition, electron microscopy revealed that TcNTPDase-1 was also found in the flagellum, flagellum insertion region, kinetoplast, nucleus and intracellular vesicles. The presence of this enzyme in the flagellum insertion region and vesicles suggests that it may have a role in nutrient acquisition, and the widespread distribution of TcNTPDase-1 within the parasite suggests that it may be involved in other biological process. Adhesion assays using anti-TcNTPDase-1 polyclonal antibodies as a blocker or purified recombinant TcNTPDase-1 as a competitor revealed that the enzyme has a role in parasite–host cell adhesion. These data open new frontiers to future studies on this specific parasite–host interaction and other unknown functions of TcNTPDase-1 related to its ubiquitous localization. 相似文献
82.
Gonadotropes are crucial in the control of reproduction but difficult to isolate for functional analysis due to their scattered distribution in the anterior pituitary gland. We devised a binary genetic approach, and describe a new mouse model that allows visualization and manipulation of gonadotrope cells. Using gene targeting in embryonic stem cells, we generated mice in which Cre recombinase is coexpressed with the GnRH receptor, which is expressed in gonadotrope cells. We show that we can direct Cre-mediated recombination of a yellow fluorescent protein reporter allele specifically in gonadotropes within the anterior pituitary of these knock-in mice. More than 99% of gonadotropin-containing cells were labeled by yellow fluorescent protein fluorescence and readily identifiable in dissociated pituitary cell culture, allowing potentially unbiased sampling from the gonadotrope population. Using electrophysiology, calcium imaging, and the study of secretion on the single-cell level, the functional properties of gonadotropes isolated from male mice were analyzed. Our studies demonstrate a significant heterogeneity in the resting properties of gonadotropes and their responses to GnRH. About 50% of gonadotropes do not exhibit secretion of LH or FSH. Application of GnRH induced a broad range of both electrophysiological responses and increases in the intracellular calcium concentration. Our mouse model will also be able to direct expression of other Cre recombination-dependent reporter genes to gonadotropes and, therefore, represents a versatile new tool in the understanding of gonadotrope biology. 相似文献
83.
Marcello Niceta Domenico Barbuti Neerja Gupta Carlos Ruggiero Eduardo F. Tizzano Luitgard Graul-Neumann Sabina Barresi Gen Nishimura Irene Valenzuela Fermina López-Grondona Paula Fernandez-Alvarez Chiara Leoni Christiane Zweier Andreas Tzschach Emilia Stellacci Andrea Del Fattore Bruno Dallapiccola Giuseppe Zampino Marco Tartaglia 《Clinical genetics》2020,97(2):362-369
84.
Elimination of B-lineage leukemia and lymphoma cells from bone marrow grafts using anti-B4-blocked-ricin immunotoxin 总被引:2,自引:0,他引:2
Denis C. Roy Claude Perreault Robert Bélanger Martin Gyger Christiane Le Houillier Walter A. Blättler John M. Lambert Jerome Ritz 《Journal of clinical immunology》1995,15(1):51-57
Bone marrow is the primary site of disease in patients with acute lymphoblastic leukemia (ALL) and is frequently involved in patients with non-Hodgkin's lymphoma (NHL). At the time of autologous bone marrow transplantation, marrow grafts from patients with leukemia and lymphoma are often still contaminated by malignant cells, even when such patients achieve complete clinical remission. In this study, we evaluated the potential of anti-B4-blocked-ricin (anti-B4-bR) immunotoxin to eliminate residual ALL and NHL cells from bone marrow. Anti-B4-bR binds to the CD19 antigen, which is B-lineage specific, and, at concentrations of 5×10–9
M or greater, could eliminate more than 3 logs of CD19+ Nalm-6 or Namalwa cells in a 20-fold excess of normal irradiated bone marrow after only 5 hr of incubation. This activity was abrogated by the addition of anti-B4 but not by the presence of galactose, which is the natural ligand for native ricin. Also, when used at these high concentrations, anti-B4-bR showed little nonspecific toxicity against normal hematopoietic progenitors. In conclusion, a single short exposure to anti-B4-bR is capable of inducing high levels of depletion of CD19+ leukemia and lymphoma cells without significant nonspecific toxicity against normal marrow progenitors. Therefore, anti-B4-bR offers an interesting approach to the elimination of B-lineage malignant cells prior to autologous bone marrow transplantation. 相似文献
85.
Long‐term follow‐up and management of small and medium‐sized CD4+ T cell lymphoma and CD8+ lymphoid proliferations of acral sites: a multicenter experience 下载免费PDF全文
86.
Fabio Luis-Silva Mayra Gonalves Menegueti Corina dos Reis Sepeda Bruno C. Petroski-Moraes Lucas Sato Leandro Moreira Peres Christiane Becari Anibal Basile-Filho Paulo R.B. Evora Olindo Assis Martins-Filho Maria Auxiliadora-Martins 《Medicine》2022,101(3)
Introduction:Septic shock is a lethal disease responsible for a large proportion of deaths in the Intensive Care Unit (ICU), even with therapy centered on fluid resuscitation, use of vasopressors and empirical antibiotic therapy applied within the first hour of diagnosis. Considering the multifactorial pathophysiology of septic shock and the mechanism of action of vasopressors, some patients may not respond adequately, which can lead to the maintenance of vasodilatation, hypotension and increased morbidity, and mortality. This protocol aims to verify whether the use of methylene blue in septic patients with an early diagnosis can contribute to an earlier resolution of a shock compared to standard treatment.Methods and analysis:This is a study protocol for a single-center randomized clinical trial design in an ICU of a tertiary university hospital. In this study, we intend to include 64 patients aged between 18 and 80 years with a diagnosis of septic shock, of any etiology, with up to 72 hours of evolution after volume restoration, using norepinephrine at a dose ≥0.2 μg/kg/min and vasopressin at a dose of 0.04 IU/min. After the initial approach, we will randomize patients into two groups, standard care, and standard care plus methylene blue. The sample size was calculated in order to show 30% differences in septic shock resolution between groups. The Research Ethics Committee approved the study, and all patients included will sign an informed consent form (Clinical registration: RBR-96584w4). 相似文献
87.
88.
89.
Ulrike Klein Kai Neben Thomas Hielscher Christiane Heiß Anthony D. Ho Hartmut Goldschmidt 《Annals of hematology》2011,90(4):429-439
Over the past decade, treatment options for patients with multiple myeloma (MM) have improved substantially, resulting in
better response rates and prolonged overall survival (OS). Nevertheless, MM remains a challenging disease, especially if renal
insufficiency (RI) or extensive pre-treatment aggravates the assignment of the optimal treatment schedule. In this retrospective
study, we analyzed the outcome of lenalidomide plus dexamethasone in 167 patients with relapsed or refractory MM with focus
on RI. The baseline creatinine clearance (CLCr) was normal in 94 patients (CLCr ≥ 80 ml/min), while RI was observed in 73 patients, including 40 patients with mild RI (50 ≤ CLCr < 80 ml/min) and 33 patients with moderate or severe RI (CLCr < 50 ml/min). Response rates declined depending on the severity of RI, being 67% among patients with normal kidney function,
60% among patients with mild RI and 49% among patients with moderate or severe RI. Time to progression (TTP) was significantly
reduced in patients with severe RI and in case of >2 previous treatment lines. OS was not significantly different between
patients with normal and impaired renal function. In contrast, the number of previous treatment lines (2 vs. <2) and the use
of novel agents like bortezomib or thalidomide prior to lenalidomide plus dexamethasone therapy had a more adverse effect
on OS. In conclusion, lenalidomide plus dexamethasone is an effective regimen for relapsed or refractory patients with MM
complicated by RI with manageable toxicity. 相似文献
90.