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31.
Several lines of evidence implicate synaptosomal‐associated protein of 25 kDa (SNAP‐25) in the etiology of attention deficit hyperactivity disorder (ADHD). Most notably, the coloboma mouse mutant, considered to be a good animal model of hyperactivity, has a deletion spanning this gene. Introducing a SNAP‐25 transgene into these animals alleviates hyperlocomotion. We have identified a novel microsatellite repeat in SNAP‐25 located between the 5′UTR and the first coding exon, and tested for association with ADHD. Case‐control analyses suggest there may be a role of this polymorphism in ADHD, with one allele over‐represented in controls and another over‐represented in probands. Within‐family tests of linkage and association confirmed these findings. Further work is needed to ascertain the role of SNAP‐25 in ADHD and assess the functional significance of this polymorphism. © 2002 Wiley‐Liss, Inc.  相似文献   
32.
Substance P (SP) belongs to a group of peptides called tachykinins. Biological effects of SP are mediated by tachykinin receptors that have been classified as neurokinin-1 (NK-1), NK-2 and NK-3 subtypes. The aim of the present study is to elucidate the tachykinin receptor subtype(s) that mediate the excitatory effects of SP in the carotid body. For this purpose, we compared the carotid body responses elicited by SP with that of physalaemin and eledoisin. In other tissues, physalaemin exhibits equi or greater potency at NK-1 receptors and eledoisin exerts its effects more on NK-2 and NK-3 subtypes compared to SP. Experiments were performed on eight cats that were anaesthetized, paralyzed and artificially ventilated with room air. Close carotid body administration of SP and physalaemin produced dose-dependent augmentation of the chemoreceptor afferent activity. Chemoreceptor discharge, however, was unaffected by eledoisin. Compared to that by SP, the magnitude of excitation produced by physalaemin was the same at lower doses but significantly greater with the highest dose (100 nmol). The time course of the response induced by physalaemin, however, was the same as that by SP. The present results demonstrate that in the carotid body physalaemin is also either equi or relatively more potent than SP, whereas eledoisin has no effect on the chemoreceptor discharge. It is suggested that stimulation of the carotid body by SP is mediated by NK-1 but not NK-2 or NK-3 receptors.  相似文献   
33.
We have investigated the frequencies of HLA-B*07 alleles and their haplotypic associations with HLA-A, -C and -DRB1 loci in 489 healthy unrelated Koreans, including 214 parents from 107 families. All of the 45 samples (9.2%) typed as B7 by serology were analyzed for B*07 alleles using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) method. Two different B*07 alleles were detected: B*0702 (allele frequency 0.041) and B*0705 (0.005). Two characteristic haplotypes showing strong linkage disequilibrium in Koreans were A*2402-Cw*07-B*0702-DRB1*0101 (haplotype frequency 0.028) and A*2901-B*0705-DRB1*0803 (0.005). The characteristic haplotype A*2901-B*0705-DRB1*0803, found in 100% (5/5) of B*0705-positive individuals, has not been previously described in other ethnic groups. HLA-B7 alleles comprise distinctive extended haplotypes in the Korean population. The probability of HLA-B7 allele mismatches among ABDR-matched unrelated donor-recipient pairs is expected to be low in Koreans.  相似文献   
34.
共患抽动障碍的ADHD儿童的脑电生物反馈治疗研究   总被引:7,自引:0,他引:7  
目的:探讨脑电生物反馈治疗共患抽动障碍的注意缺陷多动障碍(ADHD)患儿的疗效。方法:对14例符合美国精神障碍诊断与统计手册第4版(DSM-IV)诊断标准,年龄7~14岁的共患抽动障碍的ADHD患儿进行平均为34次的脑电反馈治疗,治疗前后分别采用Conner父母问卷、Achenbach 量表和Rutter问卷评定行为水平,并测试中国韦氏记忆量表、韦氏儿童智力量表(C-WISC)、持续操作性测试(CPT)等项。抽动障碍严重程度采用耶鲁全面抽动严重程度量表(Yale Global Tic Severity Scale,YGTSS)进行评定。结果:治疗后Conner父母问卷多动指数(10.6±5.6)和Rutter问卷总分(11.5±8.6)较治疗前明显下降,分别为15.7±6.0和17.2±10.5,P<0.01。Achenbach 量表多动因子分治疗后较治疗前明显下降,治疗前后分别为13.2±7.4 和7.5±3.7, P<0.05。Conner父母问卷多动分数有所下降,但差异未达显著性(P>0.05)。治疗后,患儿韦氏记忆量表的记忆商(97.8±11.7)及C-WISC中注意/不分心因子分(106.3±10.6)均高于治疗前(分别为91.3±16.3和95.5±13.0),差异具有显著性(分别为P<0 .05,P<0.01)。在CPT测试中,平均反应时下降(治疗前后分别为523.3±86.7和464.3±68.2毫秒,P<0.05),正确率提高(治疗前后分别为90%和95%,P<0.05)。14例患儿运动抽动和发声抽动在  相似文献   
35.
The purpose of this study was to determine whether the single nucleotide polymorphisms (SNPs) within candidate genes for attention deficit hyperactivity disorder (ADHD) are associated with the age at onset for ADHD. One hundred and forty-three SNPs were genotyped across five candidate genes ( DRD5 , SLC6A3 , HTR1B , SNAP25 , DRD4 ) for ADHD in 229 families with at least one affected offspring. SNPs with the highest estimated power to detect an association with age at onset were selected for each candidate gene, using a power-based screening procedure that does not compromise the nominal significance level. A time-to-onset analysis for family-based samples was performed on these SNPs to determine if an association exists with age at onset for ADHD. Seven consecutive SNPs surrounding the D5 dopamine receptor gene ( DRD5 ), were associated with the age at onset for ADHD; FDR adjusted q-values ranged from 0.008 to 0.023. This analysis indicates that individuals with the risk genotype develop ADHD earlier than individuals with any other genotype. A haplotype analysis across the 6 significant SNPs that were in linkage disequilibrium with one another, CTCATA , was also found to be significant (p-value = 0.02). We did not observe significant associations with age at onset for the other candidate loci tested. Although definitive conclusions await independent replication, these results suggest that a variant in DRD5 may affect age at onset for ADHD.  相似文献   
36.
Nutritional status in oncological patients may differ according to several modifiable and non-modifiable factors. Knowledge of the epidemiology of malnutrition/cachexia/sarcopenia may help to manage these complications early in the course of treatment, potentially impacting patient quality of life, treatment intensity, and disease outcome. Therefore, this narrative review aimed to critically evaluate the current evidence on the combined impact of tumor- and treatment-related factors on nutritional status and to draw some practical conclusions to support the multidisciplinary management of malnutrition in cancer patients. A comprehensive literature search was performed from January 2010 to December 2020 using different combinations of pertinent keywords and a critical evaluation of retrieved literature papers was conducted. The results show that the prevalence of weight loss and associated symptoms is quite heterogeneous and needs to be assessed with recognized criteria, thus allowing a clear classification and standardization of therapeutic interventions. There is a large range of variability influenced by age and social factors, comorbidities, and setting of cures (community-dwelling versus hospitalized patients). Tumor subsite is one of the major determinants of malnutrition, with pancreatic, esophageal, and other gastroenteric cancers, head and neck, and lung cancers having the highest prevalence. The advanced stage is also linked to a higher risk of developing malnutrition, as an expression of the relationship between tumor burden, inflammatory status, reduced caloric intake, and malabsorption. Finally, treatment type influences the risk of nutritional issues, both for locoregional approaches (surgery and radiotherapy) and for systemic treatment. Interestingly, personalized approaches based on the selection of the most predictive malnutrition definitions for postoperative complications according to cancer type and knowledge of specific nutritional problems associated with some new agents may positively impact disease course. Sharing common knowledge between oncologists and nutritionists may help to better address and treat malnutrition in this population.  相似文献   
37.
乳腺癌在组织学、流行病学和分子特性层面是一种高度异质性的疾病。目前,基于免疫组化的乳腺癌分类方法,根据雌激素受体、孕激素受体和人类表皮生长因子受体-2(HER-2)的检测结果将乳腺癌分为临床亚型,显然与基于基因表达谱的固有亚型分类不一致。这表现为临床亚型内治疗反应性和结果的异质性。异质性肿瘤细胞的存在直接反映了亚型内部(或肿瘤内)的异质性。乳腺癌的异质性,特别是亚克隆肿瘤细胞的异质性,决定了乳腺癌的最终治疗必须准确地针对特定的亚克隆肿瘤细胞群。对原发性和转移性乳腺癌分子特征的深入分析表明,遗传改变具有很大的异质性,分子发现有助于开发针对HER-2、细胞周期蛋白依赖性激酶4/6(CDK4/6)、磷脂酰肌醇-3激酶(PI3K)或涉及BRCA突变携带者的多聚腺苷二磷酸-核糖聚合酶抑制剂和免疫治疗的新的治疗方法。  相似文献   
38.
IntroductionThe human immunodeficiency virus 1 (HIV‐1) pandemic is characterized by numerous distinct sub‐epidemics (clusters) that continually fuel local transmission. The aims of this study were to identify active growing clusters, to understand which factors most influence the transmission dynamics, how these vary between different subtypes and how this information might contribute to effective public health responses.MethodsWe used HIV‐1 genomic sequence data linked to demographic factors that accounted for approximately 70% of all new HIV‐1 notifications in New South Wales (NSW). We assessed differences in transmission cluster dynamics between subtype B and circulating recombinant form 01_AE (CRF01_AE). Separate phylogenetic trees were estimated using 2919 subtype B and 473 CRF01_AE sequences sampled between 2004 and 2018 in combination with global sequence data and NSW‐specific clades were classified as clusters, pairs or singletons. Significant differences in demographics between subtypes were assessed with Chi‐Square statistics.ResultsWe identified 104 subtype B and 11 CRF01_AE growing clusters containing a maximum of 29 and 11 sequences for subtype B and CRF01_AE respectively. We observed a > 2‐fold increase in the number of NSW‐specific CRF01_AE clades over time. Subtype B clusters were associated with individuals reporting men who have sex with men (MSM) as their transmission risk factor, being born in Australia, and being diagnosed during the early stage of infection (p < 0.01). CRF01_AE infections clusters were associated with infections among individuals diagnosed during the early stage of infection (p < 0.05) and CRF01_AE singletons were more likely to be from infections among individuals reporting heterosexual transmission (p < 0.05). We found six subtype B clusters with an above‐average growth rate (>1.5 sequences / 6‐months) and which consisted of a majority of infections among MSM. We also found four active growing CRF01_AE clusters containing only infections among MSM. Finally, we found 47 subtype B and seven CRF01_AE clusters that contained a large gap in time (>1 year) between infections and may be indicative of intermediate transmissions via undiagnosed individuals.ConclusionsThe large number of active and growing clusters among MSM are the driving force of the ongoing epidemic in NSW for subtype B and CRF01_AE.  相似文献   
39.
Objective:The aim of this study was to explore the association between occupational exposure to diesel exhaust and polycyclic aromatic hydrocarbons (PAH), respectively, and breast cancer subtypes.Methods:The study included 38 375 women <70 years with incident breast cancer, identified in the Danish Cancer Registry, and 5 breast cancer-free controls per case who were randomly selected from the Danish Civil Registration System and matched on year of birth. Full employment history was obtained for all study subjects from a nationwide pension fund, and exposure to diesel exhaust and PAH was assessed using a job exposure matrix. Conditional logistic regression was used for estimation of odds ratios (OR) with adjustment for reproductive factors and socioeconomic status.Results:No noteworthy associations were observed for overall breast cancer in women exposed to diesel exhaust. However, diesel exhaust modestly elevated the risk of estrogen receptor negative breast tumors before age 50 [OR 1.26, 95% confidence interval (CI) 1.09–1.46]. Duration– and dose–response relationships were further observed for this subtype in this age group. No notable risk patterns were generally observed for PAH exposure.Conclusion:Occupational exposure to diesel exhaust may increase the risk of early-onset estrogen receptor negative breast tumors in women. Future studies exploring this association are warranted.  相似文献   
40.
目的探讨胆道结石术后继发急性胆管炎病原菌及可溶性CD14亚型(sCD14-ST)、白细胞介素-8(IL-8)的诊断价值。方法选择海南医学院第一附属医院2017年1月-2019年6月收治的胆道结石术后继发急性胆管炎患者62例作为研究对象,纳入研究组,选择同期医院收治的胆道结石术后未继发急性胆管炎的患者60例设为对照组;对研究组患者病原菌进行统计;比较不同急性胆管炎程度、不同预后结局患者血清sCD14-ST、IL-8水平;采用受试者工作特征曲线评估血清sCD14-ST、IL-8水平对于患者不良预后的诊断价值。结果 62例患者共培养分离病原菌67株,其中革兰阴性菌43株占64.18%,革兰阳性菌21株占31.34%,真菌3株占4.48%,以大肠埃希菌为主;重度急性胆管炎患者血清sCD14-ST、IL-8分别为(91.38±25.67)pg/ml、(45.28±13.61)pg/ml高于中度患者分别为(74.34±19.65)pg/ml、(32.06±10.44)pg/ml及轻度患者(P均<0.001),中度患者血清sCD14-ST、IL-8水平高于轻度患者(P均<0.001);预后不良患者急性胆管炎血清sCD14-ST、IL-8分别为(89.84±25.09)pg/ml、(41.94±12.28)pg/ml高于预后良好患者(P<0.05);sCD14-ST、IL-8对胆道结石术后急性胆管炎患者预后的截断值分别为65.65、29.31 pg/ml,其曲线下面积分别为0.841、0.768。结论胆道结石术后继发急性胆管炎病原以革兰阴性菌为主;运用血清sCD14-ST、IL-8可较好区分疾病严重程度,且对患者预后具有一定预测价值。  相似文献   
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