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41.
转基因(transgene)和基因打靶(gene targeting)技术通过基因的加入或删除建立了大量小鼠模型,尤其是条件性基因敲除为避免小鼠突变体在胚胎期死亡提供了条件.本文主要以参与听觉机械转导、表达于盖膜和纤毛束上的基因及其小鼠模型为例,讨论该技术是如何揭示耳聋基因的存在、功能及其作用机制的.  相似文献   
42.
转基因(transgene)和基因打靶(gene targeting)技术通过基因的加入或删除建立了大量小鼠模型,尤其是条件性基因敲除为避免小鼠突变体在胚胎期死亡提供了条件.本文主要以参与听觉机械转导、表达于盖膜和纤毛束上的基因及其小鼠模型为例,讨论该技术是如何揭示耳聋基因的存在、功能及其作用机制的.  相似文献   
43.
Epidemiologic evidence indicates an inverse association of folate intake with risk of colorectal cancer, but whether this association is modified by intake of caffeine (in coffee and tea) or cigarette smoking--factors that possibly interfere with folate--has not been studied. Thus, we examined whether the association between dietary folate intake and incidence of colorectal cancer is modified by caffeine intake and smoking. Cox proportional hazards modeling was used to estimate rate ratios relating dietary folate intake to colorectal cancer incidence among 61,433 women ages 40 to 75 years at recruitment into the Swedish Mammography Cohort in 1987 to 1990. From March 1987 through June 2004, a total of 805 incident cases of colorectal cancer were diagnosed. After controlling for age and other potential confounders, we observed an inverse association between dietary folate intake and risk of colon cancer (rate ratio for the highest versus the lowest quintile, 0.61; 95% confidence interval, 0.41-0.91; P(trend) = 0.02), but not of rectal cancer (rate ratio, 0.93; 95% confidence interval, 0.55-1.56; P(trend) = 0.97). The inverse association between dietary folate intake and colon cancer risk was most pronounced among smokers (P(interaction) = 0.03). We found no apparent modification of risk by caffeine intake. Findings from this population-based cohort study support an inverse association between dietary folate intake and risk of colon cancer and suggest that smokers might benefit most from a high dietary folate intake.  相似文献   
44.
Objective: To provide an overview of the incidence and mortality of female breast cancer for countries in the Asia-Pacific region.Methods: Statistical information about breast cancer was obtained from publicly available cancer registry and mortality databases(such as GLOBOCAN), and supplemented with data requested from individual cancer registries. Rates were directly age-standardised to the Segi World Standard population and trends were analysed using joinpoint models.Results: Breast cancer was the most common type of cancer among females in the region, accounting for 18% of all cases in 2012, and was the fourth most common cause of cancer-related deaths(9%). Although incidence rates remain much higher in New Zealand and Australia, rapid rises in recent years were observed in several Asian countries. Large increases in breast cancer mortality rates also occurred in many areas, particularly Malaysia and Thailand, in contrast to stabilising trends in Hong Kong and Singapore, while decreases have been recorded in Australia and New Zealand. Mortality trends tended to be more favourable for women aged under 50 compared to those who were 50 years or older. Conclusion: It is anticipated that incidence rates of breast cancer in developing countries throughout the Asia-Pacific region will continue to increase. Early detection and access to optimal treatment are the keys to reducing breast cancerrelated mortality, but cultural and economic obstacles persist. Consequently, the challenge is to customise breast cancer control initiatives to the particular needs of each country to ensure the best possible outcomes.  相似文献   
45.
The concept of functional neutrophil subsets is new and their clinical significance in malignancies is unknown. Our study investigated the role of CD16dim CD62Lhigh, CD16high CD62Lhigh and CD16high CD62Ldim neutrophil subsets in head and neck squamous cell carcinoma (HNSCC) patients. These neutrophil subsets may play different roles in immune‐related activity in cancer, based on their profile, activation state and migration ability within a tumor site, which may be important in predicting cancer prognoses. Tumor biopsies and blood were obtained from newly diagnosed untreated HNSCC patients and healthy controls. Neutrophil subsets and their phenotype were characterized using flow cytometry. Isolated granulocytes were assessed for anti‐tumor immune functions. Compared to controls HNSCC patients exhibited increased CD16high CD62Ldim neutrophils in blood; this subset displayed a distinct phenotypes with high expression of CD11b and CD18. This subset was prone to migrate into the tumor facilitated by tumor‐derived IL‐8. Furthermore, IL‐8 was also found to activate neutrophils and thereby promoting subset transition. Various assays demonstrated that activated CD16high CD62Ldim neutrophils inhibited migration, proliferation and induced apoptosis of FaDu cancer cells. Neutrophil elastase detected in activated CD16high CD62Ldim neutrophils and tumor biopsies suggested that CD16high CD62Ldim neutrophils impart anti‐tumoral activity via neutrophil extracellular traps. Furthermore, increased fraction of CD16high CD62Ldim neutrophils was shown to correlate with an increased survival rate. Our study demonstrates the clinical relevance of the CD16high CD62Ldim neutrophil subset, providing evidence for its increased migration capacity, its anti‐tumor activity including increased NET formation and finally its correlation with increased survival in HNSCC patients.  相似文献   
46.
Toll-like receptor 2 (TLR2) ligands are attracting attention as prophylactic and immunopotentiator agents against pathogens, including viruses. We previously reported that a synthetic diacylated lipopeptide (Mag-Pam2Cys_P48) polarized porcine macrophages towards a proinflammatory antimicrobial phenotype. Here, we investigated its role in modulating monocyte-derived macrophage (moMΦ) responses against African swine fever virus (ASFV), the etiological agent of one of the greatest threats to the global pig industry. Two ASFV isolates were compared: the attenuated NH/P68 and the virulent 26544/OG10. No effect on virus infection nor the modulation of surface markers’ expression (MHC I, MHC II DR, CD14, CD16, and CD163) were observed when Mag-Pam2Cys_P48 treated moMΦ were infected using a multiplicity of infection (MOI) of 1. Mag-Pam2Cys_P48 treated moMΦ released higher levels of IL-1α, IL-1β, IL-1Ra, and IL-18 in response to infection with NH/P68 ASFV compared to 26544/OG10-infected and mock-infected controls. Surprisingly, when infected using a MOI of 0.01, the virulent ASFV 26544/OG10 isolate replicated even slightly more efficiently in Mag-Pam2Cys_P48 treated moMΦ. These effects also extended to the treatment of moMΦ with two other lipopeptides: Mag-Pam2Cys_P80 and Mag-Pam2Cys_Mag1000. Our data suggested limited applicability of TLR2 agonists as prophylactic or immunopotentiator agents against virulent ASFV but highlighted the ability of the virulent 26544/OG10 to impair macrophage defenses.  相似文献   
47.
Central nervous system (CNS) toxicity is common at diagnosis and during treatment of pediatric acute lymphoblastic leukemia (ALL). We studied CNS toxicity in 1,464 children aged 1.0–17.9 years, diagnosed with ALL and treated according to the Nordic Society of Pediatric Hematology and Oncology ALL2008 protocol. Genome-wide association studies, and a candidate single-nucleotide polymorphism (SNP; n=19) study were performed in 1,166 patients. Findings were validated in an independent Australian cohort of children with ALL (n=797) in whom two phenotypes were evaluated: diverse CNS toxicities (n=103) and methotrexate-related CNS toxicity (n=48). In total, 135/1,464 (9.2%) patients experienced CNS toxicity for a cumulative incidence of 8.7% (95% confidence interval: 7.31–10.20) at 12 months from diagnosis. Patients aged ≥10 years had a higher risk of CNS toxicity than had younger patients (16.3% vs. 7.4%; P<0.001). The most common CNS toxicities were posterior reversible encephalopathy syndrome (n=52, 43 with seizures), sinus venous thrombosis (n=28, 9 with seizures), and isolated seizures (n=16). The most significant SNP identified by the genome-wide association studies did not reach genomic significance (lowest P-value: 1.11x10-6), but several were annotated in genes regulating neuronal functions. In candidate SNP analysis, ATXN1 rs68082256, related to epilepsy, was associated with seizures in patients <10 years (P=0.01). ATXN1 rs68082256 was validated in the Australian cohort with diverse CNS toxicities (P=0.04). The role of ATXN1 as well as the novel SNP in neurotoxicity in pediatric ALL should be further explored.  相似文献   
48.
49.
Hypothermia is a promising therapeutic strategy for severe vasospasm and other types of non-thrombotic cerebral ischemia, but its clinical application is limited by significant systemic side effects. We aimed to develop an intraventricular device for the controlled cooling of the cerebrospinal fluid, to produce a targeted hypothermia in the affected cerebral hemisphere with a minimal effect on systemic temperature. An intraventricular cooling device (acronym: V-COOL) was developed by in silico modelling, in vitro testing, and in vivo proof-of-concept application in healthy Wistar rats (n = 42). Cerebral cortical temperature, rectal temperature, and intracranial pressure were monitored at increasing flow rate (0.2 to 0.8 mL/min) and duration of application (10 to 60 min). Survival, neurological outcome, and MRI volumetric analysis of the ventricular system were assessed during the first 24 h. The V-COOL prototyping was designed to minimize extra-cranial heat transfer and intra-cranial pressure load. In vivo application of the V-COOL device produced a flow rate-dependent decrease in cerebral cortical temperature, without affecting systemic temperature. The target degree of cerebral cooling (− 3.0 °C) was obtained in 4.48 min at the flow rate of 0.4 mL/min, without significant changes in intracranial pressure. Survival and neurological outcome at 24 h showed no significant difference compared to sham-treated rats. MRI study showed a transient dilation of the ventricular system (+ 38%) in a subset of animals. The V-COOL technology provides an effective, rapid, selective, and safe cerebral cooling to a clinically relevant degree of − 3.0 °C.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-022-01302-y.  相似文献   
50.
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