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61.
62.
Effects of rhG-CSF on neutrophil functions and bone marrow parameters in diabetic rats 总被引:1,自引:0,他引:1
Cantürk Z Cantürk NZ Cetinarslan B Erçin C Dökmetaş S Sencan M 《Endocrine research》1999,25(3-4):381-395
Neutrophils have an important role in the host defense. The elevated serum glucose levels of diabetics affect traditional host defenses such as neutrophil counts and functions. The causes of these impairments are not clear. We aimed to investigate changes of peripheral neutrophil counts and functions and their relation with bone marrow cells in diabetic rats. Thirty-two rats were divided into four equal groups. Group 1 were controls and Groups 2 and 4 were made diabetic by a single intraperitoneal injection of streptozotocin. Granulocyte colony stimulating factor (G-CSF) was injected subcutaneously into Groups 3 and 4. White blood cell count, neutrophil counts and function and bone marrow cell count were determined. Peripheral blood cell counts, neutrophil phagocytosis index were decreased but neutrophil adhesivity index was not different in the diabetes-induced group. There was a difference in circulating white blood cell counts and neutrophil counts between the rhG-CSF treated and non-treated groups. The phagocytosis index of neutrophil in diabetic rats was significantly diminished by rhG-CSF treatment. A hyperplasia of early cells of the myeloid series in G-CSF treated groups was observed when compared with those of nontreated groups (p<0.001). A significant decrease was noted in the number of mature marrow segmented cells diabetic groups (p<0.001). Finally, G-CSF has been shown to cause neutrophilia by acting as a releasing factor for mature marrow neutrophils in diabetic rats. These results suggest that G-CSF may be used to improve nonspecific immunity in diabetic patients. 相似文献
63.
Theresa Cole Fiona McKendrick Penny Titman Andrew J. Cant Mark S. Pearce Catherine M. Cale David Goldblatt Andrew R. Gennery 《Journal of clinical immunology》2013,33(1):8-13
Purpose
Chronic Granulomatous Disease (CGD) is a rare primary immunodeficiency that predisposes to life-threatening infections and inflammation. Haematopoietic stem cell transplant (HSCT) can cure CGD. Chronic illness reduces quality of life. Children with haematological malignancies report improved quality of life post-HSCT. There are no data for children with CGD. This study evaluated quality of life and emotional well-being in CGD children treated conventionally or transplanted.Methods
Parents and children completed the Pediatric Quality of Life Inventory v4.0 (PedsQL) and Strengths and Difficulties Questionnaires (SDQ). Mean scores were compared with published UK norms. Comparisons were made for those that had or had not undergone HSCT.Results
Forty-seven parents completed PedsQL (children aged 3–15). Twenty-one were post-HSCT. Forty-two completed SDQ (children aged 3–15). Nineteen post-HSCT. Median age for non-HSCT group 9 years. Median age for post-HSCT group 10 years. The HSCT group were median 3 years post-HSCT (range 1–9 years). HSCT survival was 90 %—two died without completing questionnaires Parent and self-reported quality of life for non-transplanted children was significantly lower than healthy children. Parents reported increased emotional difficulties compared to published norms. PedsQL and SDQ scores for transplanted children were not significantly different from healthy norms.Conclusions
This study demonstrates the quality of life is reduced in CGD. Transplanted patients have quality of life comparable to levels reported in healthy children. This data will help inform families and clinicians when deciding about treatment and may have relevance for other immunodeficiencies treated with transplant. 相似文献64.
Nicole Lovato Leon Lack Helen Wright Megan Cant Joanne Humphreys 《Journal of sleep research》2013,22(3):251-257
Older individuals suffering insomnia typically report declines in their cognitive performance beyond what they consider to be normal changes due to the aging process. Recent neuro‐imaging studies have demonstrated frontal lobe hypo‐activation among insomniac populations when compared with healthy, good sleepers. However, research is yet to confirm whether frontal lobe hypo‐activation translates into objective declines when performing tasks hypothesized to draw upon this brain region. This study aimed to investigate whether older insomnia sufferers demonstrate significantly impaired performance on a challenging working memory task when compared with age‐matched good sleepers. Forty‐nine older individuals (mean age = 69.43 years, SD = 4.83) suffering from sleep maintenance insomnia were compared with 49 age‐matched good sleepers. Cognitive performance was assessed using the Double Span Memory Task, a computer‐based working memory task that requires participants to indicate the names and/or spatial locations of increasingly longer sequences of visually presented objects. After controlling for general intelligence, the individuals suffering from insomnia did not perform differently when compared with the good sleepers on either the simpler or more cognitively demanding components of the task. Older individuals with insomnia did not display an observable impairment of working memory in this study relative to good sleepers. Despite the mixed results from previous research, this study adds weight to the absence of objective impairment in insomniacs, at least while performing short‐term demanding cognitive tasks. 相似文献
65.
M. Díez-Aguilar P. Ruiz-Garbajosa A. Fernández-Olmos P. Guisado R. Del Campo C. Quereda R. Cantón M. A. Meseguer 《European journal of clinical microbiology & infectious diseases》2013,32(6):769-772
The purpose of the study was to describe the microbiological and clinical features of ten cases of lower respiratory tract infection due to Corynebacterium striatum, Corynebacterium propinquum and Corynebacterium pseudodiphtheriticum. Respiratory samples were recovered from hospitalised patients who were diagnosed of pneumonia and exacerbations of chronic respiratory infections. The samples were Gram-stained and seeded on conventional bacterial growing media. Bacteria were identified by matrix-assisted linear desorption/ionisation–time-of-flight mass spectrometry (MALDI-TOF MS). Antibiotic susceptibility was tested by the disk diffusion method. All patients presented an acute respiratory onset, most of them in the context of an underlying disease and/or immunosuppression. In all patients, the microscopical examination of Gram-stained respiratory samples showed numerous polymorphonuclear cells and Gram-positive bacilli, suggestive of the Corynebacterium morphotype. A pure culture growth of Corynebacterium was obtained in the majority (72 %) of samples. The conclusions are that non-diphtheriae Corynebacterium species are an emerging cause of respiratory infection among patients with chronic respiratory disease and/or immunosuppression, and cannot always be considered as mere colonisers. The microorganism’s predominance in Gram-stained purulent respiratory samples together with abundant growth in the culture is the key for the microbiological diagnosis. 相似文献
66.
Marcela Rodríguez-Flores Joel Rodríguez-Saldaña Carlos Cantú-Brito Jesús Aguirre-García González-Garay Alejandro 《Cardiovascular pathology》2013,22(5):332-338
BackgroundThere is uneven association between obesity, traditional risk factors, and cardiovascular events. We aimed to analyze the relation between cardiovascular risk factors, including obesity, with the severity of atherosclerosis in different arterial territories.MethodsArteries from five territories (circle of Willis, carotids, coronaries, aorta, and renal) were taken from 185 persons, newborn to 90 years undergoing autopsy in the Forensic Medical Service in Mexico City, to determine atherosclerotic lesions by histopathological study. Lesions were classified according to the American Heart Association grading system as early (types I–III) and advanced (types IV–VI). The degree of atherosclerosis was correlated with arterial territories and risk factors.ResultsFrequencies of advanced lesions according to arterial territories were as follows: circle of Willis, 28%; right carotid, 36%; left carotid, 25%; right coronary, 71%; left coronary, 85%; right renal, 26%; left renal, 29%; and aorta, 52%; P=.0001, for all analyses. There was a higher risk for advanced lesions with increasing body mass index (BMI) (P=.004). However, after adjusting for age, gender, smoking status, hypertension, and diabetes mellitus, BMI was not independently associated with advanced lesions.ConclusionsCoronary arteries are significantly more affected than other arterial territories regardless of risk factors, showing the effect of local and systemic factors in the severity of atherosclerosis. We did not find an independent association between advanced atherosclerotic lesions and obesity. 相似文献
67.
Antioxidative effects of cysteamine,hyaluronan and fetuin on post‐thaw semen quality,DNA integrity and oxidative stress parameters in the Brown Swiss bull 下载免费PDF全文
S. Sarıözkan P. B. Tuncer S. Büyükleblebici M. N. Bucak F. Cantürk A. Eken 《Andrologia》2015,47(2):138-147
The aim of this study was to compare the effectiveness of antioxidants including cysteamine (2.5, 7.5 mm ), hyaluronan (0.25, 1 mg ml?1) and fetuin (5, 10 mg ml?1) in the freezing of Brown Swiss bull semen. The best percentages of CASA motilities were achieved with 10 mg ml?1 of fetuin and 2.5 mm of cysteamine. For sperm morphology, 10 mg ml?1 of fetuin and 2.5 mm of cysteamine had better protective effects (P < 0.001). The results of hypo‐osmotic swelling test showed that the percentage values of membrane integrity in all the groups, excluding that supplemented with 5 mg ml?1 of fetuin, were higher than those of the control group (P < 0.001). Results obtained for the DNA damage of sperm cells demonstrated that 0.25 mg ml?1 of hyaluronan, and 2.5 and 7.5 mm of cysteamine led to lower rates of spermatozoa with damaged DNA, compared with the control group (P < 0.001). The maintenance of superoxide dismutase and glutathione peroxidase antioxidant activities following freeze‐thawing with 2.5 and 7.5 mm of cysteamine and 10 mg ml?1 of fetuin was demonstrated to be at a higher level in comparison with the control group (P < 0.001). Malondialdehyde formation was found to be lower in the groups supplemented with 0.25 mg ml?1 of hyaluronan and 7.5 mm of cysteamine after the freeze‐thawing process (P < 0.001). 相似文献
68.
Tingting Wang Lei Mo Ce Mo Li Hai Tan Jonathan S. Cant Luojin Zhong Gerald Cupchik 《Social cognitive and affective neuroscience》2015,10(6):814-823
Is moral beauty different from facial beauty? Two functional magnetic resonance imaging experiments were performed to answer this question. Experiment 1 investigated the network of moral aesthetic judgments and facial aesthetic judgments. Participants performed aesthetic judgments and gender judgments on both faces and scenes containing moral acts. The conjunction analysis of the contrasts ‘facial aesthetic judgment > facial gender judgment’ and ‘scene moral aesthetic judgment > scene gender judgment’ identified the common involvement of the orbitofrontal cortex (OFC), inferior temporal gyrus and medial superior frontal gyrus, suggesting that both types of aesthetic judgments are based on the orchestration of perceptual, emotional and cognitive components. Experiment 2 examined the network of facial beauty and moral beauty during implicit perception. Participants performed a non-aesthetic judgment task on both faces (beautiful vs common) and scenes (containing morally beautiful vs neutral information). We observed that facial beauty (beautiful faces > common faces) involved both the cortical reward region OFC and the subcortical reward region putamen, whereas moral beauty (moral beauty scenes > moral neutral scenes) only involved the OFC. Moreover, compared with facial beauty, moral beauty spanned a larger-scale cortical network, indicating more advanced and complex cerebral representations characterizing moral beauty. 相似文献
69.
Durante W; Schini VB; Kroll MH; Catovsky S; Scott-Burden T; White JG; Vanhoutte PM; Schafer AI 《Blood》1994,83(7):1831-1838
We have investigated the role of platelets in regulating the hemostatic and vasomotor properties of vascular smooth muscle. Experiments were performed to examine the effect of the releasate from activated platelets on the production of nitric oxide from interleukin-1 beta (IL- 1 beta)-treated cultured rat aortic smooth muscle cells. Treatment of vascular smooth muscle cells with IL-1 beta resulted in significant accumulation of nitrite in the culture media and in marked elevation of intracellular cyclic guanosine monophosphate (GMP) levels. The releasate from collagen-aggregated platelets blocked the IL-1 beta- mediated production of nitrite and the accumulation of cyclic GMP in smooth muscle cells in a platelet number-dependent manner. In functional assays, the perfusates from columns containing IL-1 beta- treated smooth muscle cells relaxed detector blood vessels without endothelium and the addition of IL-1 beta-treated smooth muscle cells to suspensions of platelets inhibited their thrombin-induced aggregation. The simultaneous treatment of smooth muscle cells with IL- 1 beta and the platelet releasate abolished both the vasorelaxing activities of the perfusates and the inhibition of platelet aggregation. Platelet releasates treated with a neutralizing antibody to platelet-derived growth factor (PDGF) failed to block IL-1 beta- induced nitric oxide production by the smooth muscle cells, as measured by both biochemical and functional assays. The platelet releasate from a patient with gray platelet syndrome likewise failed to block IL-1 beta-induced nitrite release by smooth muscle cells. These results demonstrate that platelets downregulate the production of nitric oxide by IL-1 beta-treated vascular smooth muscle cells through the release of PDGF. This effect may represent a novel mechanism by which platelets regulate vasomotor tone and thrombus formation at sites of vascular injury. 相似文献
70.
Seiffert M Cant C Chen Z Rappold I Brugger W Kanz L Brown EJ Ullrich A Bühring HJ 《Blood》1999,94(11):3633-3643
Signal-regulatory proteins (SIRPs) comprise a novel transmembrane glycoprotein family involved in the negative regulation of receptor tyrosine kinase-coupled signaling pathways. To analyze the expression and function of SIRPs, we prepared soluble recombinant fusion proteins of the extracellular regions of SIRPalpha1 and SIRPalpha2, as well as a variety of monoclonal antibodies (MoAbs) against these domains. The antibodies reacted predominantly with monocytes, granulocytes, dendritic cells, and their precursors, as well as with bone marrow CD34(+), AC133(+), CD90(+) hematopoietic stem/progenitor cells. In contrast, SIRP expression was absent or significantly reduced on the majority of myeloid blasts from patients with acute myeloid leukemia (AML) or chronic myeloid leukemia (CML). Functional studies showed that the extracellular domains of SIRPalpha1 and SIRPalpha2 support adhesion of a number of primary hematopoietic cells and cell lines. This interaction could be blocked by 4 of 7 SIRPalpha1-reactive MoAbs. In addition, SIRPalpha1 and SIRPalpha2 competed for the same cell binding site, suggesting a common widely expressed SIRP ligand. In an approach to identify this molecule, MoAbs were generated against the SIRP-binding cell line CCRF-CEM, and MoAb CC2C6 was selected because of its capacity to inhibit cell binding to SIRPalpha1. Further analysis showed that this antibody recognized CD47, a ubiquitously expressed plasma membrane protein previously implicated in integrin function, host defense action, and neutrophil migration. In this study, we identify CD47 as the extracellular ligand for human SIRP and show that these two counterreceptors are involved in cellular adhesion. 相似文献