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991.
OBJECTIVE: Studies of Wegener's granulomatosis (WG) since the late 1980s indicate a probable increase in incidence of unknown cause and significance, possibly related to antineutrophil cytoplasmic antibody (ANCA) testing. To extend these observations and to include calendar periods before ANCA was introduced, we assessed time trends in the incidence of WG in Sweden in the period 1975-2001. METHODS: In the population-based Swedish Inpatient Register, we identified 1938 individuals diagnosed with WG in the period 1975-2001, and calculated the annual age and sex adjusted incidences. RESULTS: The incidence increased from 0.33 (95% CI 0.28-0.39) in the period 1975-85 to 0.77 (95% CI 0.69-0.85) in 1986-90, to 1.19 (95% CI 1.12-1.26) in 1991-2001, resulting in a mean incidence of 0.78 (95% CI 0.74-0.82). CONCLUSION: WG displays a strong temporal trend. While the increase coincides to some extent with the implementation of ANCA testing, suggestive of increased disease recognition, ANCA testing remains an incomplete explanation as increasing incidences were noted before as well as after their introduction. 相似文献
992.
Wu H Wang YM Wang Y Hu M Zhang GY Knight JF Harris DC Alexander SI 《Journal of the American Society of Nephrology : JASN》2007,18(4):1180-1189
It has been reported that the presence of gammadelta T cells in kidney is associated with kidney damage in human IgA nephropathy and in rat models of chronic renal injury, including Adriamycin nephropathy (AN), but the functional role of gammadelta T cells in this setting is unknown. This study examined the functional role of gammadelta T cells in tissue injury in a murine model of AN. Murine AN was induced in BALB/c mice by a single injection of Adriamycin. gammadelta T cells as a proportion of CD3(+) T cells were significantly increased in AN kidneys (16.8 +/- 3.9%) but not in lymph nodes (1.3 +/- 0.8%; P < 0.001). The proportion of gammadelta T cells in AN kidney correlated positively with serum creatinine and glomerular sclerosis. The Vgammadelta T cell receptor (TCR) repertoire in kidney showed expansion of a subset of cells that expressed Vgamma6/Vdelta1 genes and that used canonical TCR Vgamma6/Vdelta1 sequences in the CDR3 region of the TCR. gammadelta T cells that were sorted from the kidneys expressed TGF-beta but not IL-4, IL-10, or IFN-gamma. gammadelta T cells also expressed the activating receptor NKG2D and the NKG2D adaptor molecule DAP12. RAE-1, a ligand of NKG2D, was upregulated in AN kidney. Depletion of gammadelta T cells using anti-TCR gammadelta antibody resulted in worsening of serum creatinine, glomerulosclerosis, and interstitial inflammation. These studies indicate the involvement of the gammadelta T cell in innate recognition and regulation of inflammation in AN. 相似文献
993.
Context shapes perception, thought, and action, but little is known about the neural mechanisms supporting these modulations. Here, we addressed the role of lateral prefrontal cortex (PFC) in context updating and maintenance from an information-theoretic perspective. Ten patients with PFC lesions and 10 age-matched controls responded to bilaterally displayed visual targets intermixed with repetitive and novel distracters in 2 different task contexts. In a predictable context, targets were always preceded by a novel event, whereas this temporal contingency was removed in an unpredictable context condition. We applied information theory to the analysis and interpretation of behavioral and electrophysiological data. The results revealed deficits in both the selection and the suppression of familiar versus novel information mainly observed at the visual hemifield contralateral to PFC damage due to disrupted frontocortical and frontosubcortical connectivity. The findings support a deficit in the representation of the temporal contingency between contextually related novel and familiar stimulation subsequent to lateral PFC damage. 相似文献
994.
Atherosclerosis is a major global cause of morbidity and mortality, and diabetes patients are at increased risk of coronary heart disease development. Advanced glycation of proteins occurs in the body due to raised concentrations of reducing sugars and reactive oxygen species, and is a causal factor behind complications of diabetes. Glycated proteins, through alteration of protein structure and function, and from ligation with their receptors, lead to widespread vascular damage. The alpha-oxoaldehyde, methylglyoxal (MG) is the most reactive glycation precursor, and is increased in the blood of diabetes patients. There is debate about the triggering events leading to atherosclerosis, but the inflammatory action of glycated proteins, including those with MG adducts, through their receptor, RAGE, is a major candidate for initiating plaque formation. In addition glycation may cause cross-links on proteins of the extracellular matrix, stiffening arteries and 'trapping' other macromolecules. MG is also likely to form adducts on many other proteins, enzymes, lipids, DNA or RNA, changing their structure, and may disrupt enzyme activity, hormone regulation and immune function. In the latter context, MG disrupts function of the potent antigen presenting cells, dendritic cells. This effect may be a double edged sword: Poor control of infections may contribute to persistent inflammation, whilst inhibition of immune activation by dendritic cells may inhibit plaque progression. This review aims to present these ideas as a novel slant on the role of the glycation process in atherosclerosis. 相似文献
995.
Mechanisms of action of probiotics: recent advances 总被引:1,自引:0,他引:1
The intestinal microbiota plays a fundamental role in maintaining immune homeostasis. In controlled clinical trials probiotic bacteria have demonstrated a benefit in treating gastrointestinal diseases, including infectious diarrhea in children, recurrent Clostridium difficile-induced infection, and some inflammatory bowel diseases. This evidence has led to the proof of principle that probiotic bacteria can be used as a therapeutic strategy to ameliorate human diseases. The precise mechanisms influencing the crosstalk between the microbe and the host remain unclear but there is growing evidence to suggest that the functioning of the immune system at both a systemic and a mucosal level can be modulated by bacteria in the gut. Recent compelling evidence has demonstrated that manipulating the microbiota can influence the host. Several new mechanisms by which probiotics exert their beneficial effects have been identified and it is now clear that significant differences exist between different probiotic bacterial species and strains; organisms need to be selected in a more rational manner to treat disease. Mechanisms contributing to altered immune function in vivo induced by probiotic bacteria may include modulation of the microbiota itself, improved barrier function with consequent reduction in immune exposure to microbiota, and direct effects of bacteria on different epithelial and immune cell types. These effects are discussed with an emphasis on those organisms that have been used to treat human inflammatory bowel diseases in controlled clinical trials. 相似文献
996.
Jessica E. Knight‐Perry BSc Joshua J. Field MD Michael R. DeBaun MD MPH Janet Stocks PhD Jane Kirkby BSc Robert C. Strunk MD 《Pediatric pulmonology》2009,44(7):728-730
Asthma is associated with increases in sickle cell disease (SCD)‐related morbidity and mortality. A thorough evaluation for asthma in children with SCD is important and may involve methacholine challenge (MCh). In this report, we present a 14‐year‐old male with SCD who was admitted for an acute painful episode following MCh. Pain events after MCh have not been previously reported in children with SCD. The risk–benefit ratio should be strongly considered prior to performance of MCh in this patient population, and all possible complications, including an acute painful episode, should be openly discussed with the parents and pediatric patient. Pediatr Pulmonol. 2009; 44:728–730. © 2009 Wiley‐Liss, Inc. 相似文献
997.
Van Bebber SL Trosman JR Liang SY Wang G Marshall DA Knight S Phillips KA 《Personalized medicine》2010,7(4):427-439
This article focuses on the overarching question: how can we use existing data to develop the capacity to improve the evidence base on personalized medicine technologies and particularly regarding their utilization and clinical utility? We focus on data from health payers who are key stakeholders in capacity building, as they need data to guide decisions and they develop data as part of operations. Broadly defined, health payers include insurance carriers, third party payers, health-plan sponsors and organized delivery systems. Data from health payers have not yet been widely used to assess personalized medicine. Now, with an increasing number of personalized technologies covered and reimbursed by health payers, and an increasing number of emerging technologies that will require policy decisions, there is a great opportunity to develop the evidence base using payer data and by engaging with these stakeholders. Here, we describe data that are available from, and are being developed by, health payers and assess how these data can be further developed to increase the capacity for future research, using three examples. The examples suggest that payer data can be used to examine clinical utility and approaches can be developed that simultaneously address the characteristics of personalized medicine, real world data and organizations. These examples can now help us to elucidate how to best examine clinical utility in actual practice and build evaluation approaches that can be applied to future technologies. 相似文献
998.
Vaughan NM Grainger J Bader DL Knight MM 《Medical & biological engineering & computing》2010,48(12):1215-1222
Pulsed low intensity ultrasound (PLIUS) has been used successfully for bone fracture repair and has therefore been suggested
for cartilage regeneration. However, previous in vitro studies with chondrocytes show conflicting results as to the effect
of PLIUS on the elaboration of extracellular matrix. This study tests the hypothesis that PLIUS, applied for 20 min/day, stimulates
the synthesis of sulphated glycosaminoglycan (sGAG) by adult bovine articular chondrocytes cultured in either monolayer or
agarose constructs. For both culture models, PLIUS at either 30 or 100 mW/cm2 intensity had no net effect on the total sGAG content. Although PLIUS at 100 mW/cm2 did induce a 20% increase in sGAG content at day 2 of culture in agarose, this response was lost by day 5. Intensities of
200 and 300 mW/cm2 resulted in cell death probably due to heating from the ultrasound transducers. The lack of a sustained up-regulation of
sGAG synthesis may reflect the suggestion that PLIUS only induces a stimulatory effect in the presence of a tissue injury
response. These results suggest that PLIUS has a limited potential to provide an effective method of stimulating matrix production
as part of a tissue engineering strategy for cartilage repair. 相似文献
999.
Sutton WK Knight A Underhill PA Neulander JS Disotell TR Mountain JL 《Annals of human biology》2006,33(1):100-111
BACKGROUND: The ethnic heritage of northernmost New Spain, including present-day northern New Mexico and southernmost Colorado, USA, is intensely debated. Local Spanish-American folkways and anecdotal narratives led to claims that the region was colonized primarily by secret- or crypto-Jews. Despite ethnographic criticisms, the notion of substantial crypto-Jewish ancestry among Spanish-Americans persists. AIM: We tested the null hypothesis that Spanish-Americans of northern New Mexico carry essentially the same profile of paternally inherited DNA variation as the peoples of Iberia, and the relevant alternative hypothesis that the sampled Spanish-Americans possess inherited DNA variation that reflects Jewish ancestry significantly greater than that in present-day Iberia. SUBJECTS AND METHODS: We report frequencies of 19 Y-chromosome unique event polymorphism (UEP) biallelic markers for 139 men from across northern New Mexico and southern Colorado, USA, who self-identify as 'Spanish-American'. We used three different statistical tests of differentiation to compare frequencies of major UEP-defined clades or haplogroups with published data for Iberians, Jews, and other Mediterranean populations. We also report frequencies of derived UEP markers within each major haplogroup, compared with published data for relevant populations. RESULTS: All tests of differentiation showed that, for frequencies of the major UEP-defined clades, Spanish-Americans and Iberians are statistically indistinguishable. All other pairwise comparisons, including between Spanish-Americans and Jews, and Iberians and Jews, revealed highly significant differences in UEP frequencies. CONCLUSION: Our results indicate that paternal genetic inheritance of Spanish-Americans is indistinguishable from that of Iberians and refute the popular and widely publicized scenario of significant crypto-Jewish ancestry of the Spanish-American population. 相似文献
1000.
MLL chimeric protein activation renders cells vulnerable to chromosomal damage: an explanation for the very short latency of infant leukemia 总被引:1,自引:0,他引:1
Eguchi M Eguchi-Ishimae M Knight D Kearney L Slany R Greaves M 《Genes, chromosomes & cancer》2006,45(8):754-760
MLL fusion genes are a predominant feature of acute leukemias in infants and in secondary acute myeloid leukemia (AML) associated with prior chemotherapy with topo-II poisons. The former is considered to possibly arise in utero via transplacental chemical exposure. A striking feature of these leukemias is their malignancy and remarkably brief latencies implying the rapid acquisition of any necessary additional mutations. We have suggested that these coupled features might be explained if MLL fusion gene encoded proteins rendered cells more vulnerable to further DNA damage and mutation in the presence of chronic exposure to the agent(s) that induced the MLL fusion itself. We have tested this idea by exploiting a hormone regulated MLL-ENL (MLLT1) activation system and show that MLL-ENL function in normal murine progenitor cells substantially increases the incidence of chromosomal abnormalities in proliferating cells that survive exposure to etoposide VP-16. This phenotype is associated with an altered pattern of cell cycle arrest and/or apoptosis. 相似文献