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171.
Objectives: We aimed to establish whether macrosomic fetuses in pregnancies complicated by gestational diabetes (GDM) show different Pulsatility Index (PI) values in umbilical artery (UA) than in non-macrosomic fetuses.

Methods: We considered 106 pregnant women with GDM. Doppler recordings of UA-PI were performed at 34–41 weeks and related to neonatal birthweight. Pregnancies were divided in two groups according to birthweight, macrosomic group (>4000?g) and controls (<4000?g), and according to birthweight centile,?>90th centile and?<90th centile. Differences in UA-PI and maternal and fetal characteristics between groups were tested.

Results: Mean UA-PI was significantly lower in newborns with birthweight?>4000?g than in controls (PI?=?0.69; 95% CI 0.64–0.74 versus PI?=?0.87; 95% CI 0.84–0.90, p?<?000.1). Mean UA-PI was significantly lower in newborns with birthweight centile?>90th centile than in controls (PI?=?0.79; 95% CI 0.74–0.84 versus PI?=?0.87; 95% CI 0.83–0.90; t?=?2.653; p?=?0.01). Linear regression analysis revealed a significant correlation between UA-PI and neonatal birthweight and between UA-PI and neonatal birthweight centile.

Conclusions: Macrosomic fetuses of pregnancies complicated by GDM show lower values of UA-PI compared with controls. Despite UA-PI results, a variable related to macrosomia its role in the management of these pregnancies remains to be established.  相似文献   
172.
Biliary atresia in infants occasionally presents as intracranial, nasal or gastrointestinal bleeding, instead of the classical triad of jaundice, acholia and choluria. We present two female infants aged four and two months, who were hospitalized with convulsive episode, cephalohematoma and drowsiness. Computed tomography findings were subdural hemorrhage in one patient and intraventricular and parenchymal bleeding in the other one. At admission they have history, clinical and laboratory signs of cholestasis of unknown etiology. The patient with subdural hemorrhage required surgical drainage. The other girl with intraventricular and parenchymal bleeding received vitamin K and no surgery. Biliary atresia was diagnosed and treated in both girls. At six months both had an adequate neurological outcome and required liver transplantation at one year old. Biliary atresia should be considered in all infants with sudden acute bleeding and cholestasis.  相似文献   
173.
A kindred with MYH-associated polyposis and pilomatricomas   总被引:4,自引:0,他引:4  
MYH-associated polyposis (MAP) is a recently described autosomal recessive form of familial adenomatous polyposis (FAP) associated with susceptibility to colorectal carcinoma (CRC). MAP is caused by biallelic inactivating mutations of the MYH gene, a component of the base excision repair (BER) machinery, whose dysfunction leads to an increase in the rate of G > T transversions following DNA oxidative damage. MAP patients can present with either classic or attenuated polyposis. However, the MAP colonic and extracolonic phenotype has yet to be defined. We report on two siblings, born from consanguineous parents, who were found to be homozygotes for an MYH frameshift mutation. The propositus presented with a low number of colonic lesions and an early-onset CRC. Both siblings had a history of pilomatricomas, benign tumors derived from hair follicles, in childhood. The findings presented provide further evidence of phenotypic variability in MAP, and suggest that multiple pilomatricomas may be a useful cutaneous marker of MAP.  相似文献   
174.
We applied a family-based association approach to investigate the role of the DYX1C1 gene on chromosome 15q as a candidate gene for developmental dyslexia (DD) to 158 families containing at least one dyslexic child. We directly sequenced exons 2 and 10 of the DYX1C1 gene and found eight single nucleotide polymorphism (SNPs), three of which (-3G>A, 1249 G>T, 1259 C>G) were suitable for the genetic analyses. We performed single- and multimarker association analyses with DD as a categorical trait by FBAT version 1.4 and TRANSMIT version 2.5.4 programs. Our sample had a power of at least 80% to detect an association between the selected phenotypes and the informative polymorphisms at a significance level of 5%. The results of the categorical analyses did not support the involvement of the DYX1C1 gene variants in this sample of dyslexics and their relatives. Quantitative and multimarker analyses, which provide greater power to detect loci with a minor effect, consistently yielded nonsignificant results. While D1X1C1 is a good candidate gene for DD, we were unable to replicate the original findings between DYX1C1 gene and DD, perhaps due to genetic heterogeneity.  相似文献   
175.
BACKGROUND: Asthma is a heterogeneous process, yet little is understood regarding phenotypes. OBJECTIVE: To determine whether phenotypic differences exist between early-onset, severe asthma as compared with late-onset disease and whether the presence or absence of eosinophilia influences the phenotypes. METHODS: Cross-sectional analysis of integrated clinical, physiologic, and pathologic data collected from 80 subjects with severe asthma. Subjects were divided into those with asthma onset before age 12 years (n = 50) versus after age 12 (n = 30) and by the presence or absence of lung eosinophils. RESULTS: Subjects with early-onset, severe asthma had significantly more allergen sensitivity (skin test positivity, 98% vs 76%, P <.007) and more allergic symptoms (P values all 相似文献   
176.
Trypanosoma cruzi is an intracellular parasite that induces a strong Th1-type response and immunosuppression during the acute phase of infection. To study how the infection with T. cruzi would modulate the development of an autoimmune disease, we immunized C57BL/6 mice and IL-10 or iNOS knock-out mice of the same background with the encephalitogenic MOG 35-55 peptide and infected them with T. cruzi. Our results demonstrate that infection with T. cruzi completely prevents EAE development and furthermore induces complete and lasting remission in mice that were infected with this parasite after they had developed clinical EAE. Nitric oxide and IL-10 participate in triggering the mechanisms associated with EAE suppression by the infection. Decreased lymphoproliferation and increased frequencies of Annexin-positive cells and of T cells bearing CD95, CD95L or CTLA-4 were observed in the spleen from immunized/infected mice, as well as lower IL-2 and increased TGF-beta production in comparison with only immunized mice. Our results indicate that several effector and regulatory mechanisms of the immune response that arise during the acute phase of T. cruzi infection lastingly affect the expansion and/or effector functions of encephalitogenic cells, preventing the onset or inducing complete remission of EAE.  相似文献   
177.
Molecular cytogenetic characterization of proximal-type epithelioid sarcoma   总被引:2,自引:0,他引:2  
Proximal-type epithelioid sarcoma is a recently described soft-tissue tumor that is distinguished from conventional-type epithelioid sarcoma by a far more aggressive clinical course, frequent location in the proximal anatomic regions, and variable rhabdoid morphology. Because of their rarity and peculiar morphology, proximal-type epithelioid sarcomas frequently pose serious diagnostic dilemmas, being easily misdiagnosed as a variety of other malignant neoplasms. To date, the information available on the genetic alterations associated with this tumor entity has been confined to single conventional cytogenetic reports. In this article, we present the results of a conventional and molecular cytogenetic analysis of six proximal-type epithelioid sarcomas. Spectral karyotyping analysis of these cases deciphered the characteristics of several marker chromosomes and complex translocations, leading to the recognition of recurrent rearrangements. The most frequently involved chromosome arm was 22q, and the identification of two cases with a similar translocation, t(10;22), suggests a role for one or more genes on chromosome 22 in the pathogenesis of this tumor and provides an opportunity for finely mapping the translocation-associated breakpoints. Chromosome arm 8q gain was also a frequent event and correlated with gain of MYC gene copy number, as demonstrated by fluorescence in situ hybridization. A review of both cases reported in the literature and those presented in this study reinforced the involvement of chromosomes 8 and 22 and also indicated frequent rearrangements of chromosomes 7, 14, 18, and 20.  相似文献   
178.
The human small-conductance Ca(2+)-activated potassium channel gene KCNN3 has been involved in mechanisms underlying neuronal function and plasticity. A multiallelic CAG repeat polymorphism within the KCNN3 has been associated with schizophrenia and bipolar disorder. We have previously reported in a family-based study that longer CAG repeats are preferentially transmitted to patients with anorexia nervosa (AN). The present study extends the analysis of KCNN3 allele distribution to a larger series of AN female patients and control groups, incorporating information on ethnicity and co-morbidities associated with AN. The data analysis is presented while considering separately the two alleles of each individual, namely a minor (shorter) and a major (longer) allele. This study has found that the KCNN3 allele distribution in the general Israeli population does not differ significantly in at least four Jewish ethnic groups of Ashkenazi, North African, Iraqi, and Yemenite origin. These have been used as control groups in a matched case-control analysis that has demonstrated a significant over-representation of KCNN3 alleles with longer CAG repeats among AN patients (P < 0.001 for the major allele and P = 0.035 for allele sum). Under dichotomization, a significantly higher prevalence of the L allele (>19 repeats) has been observed among AN patients (P < 0.001). While considering AN and co-morbid phenotypes, a tendency towards longer (L) alleles has been observed in the subset of patients with obsessive-compulsive disorder (OCD) co-morbidity. These findings further implicate KCNN3 as a significant contributor to predisposition to AN.  相似文献   
179.
180.
Objective: The Brazilian-Portuguese hearing in noise test (HINT) was used to investigate the benefit to speech recognition of listening in a fluctuating background. The goal was to determine whether modulation masking release varied as a function of the speech-to-masker ratio at threshold. Speech-to-masker ratio at threshold was manipulated using the novel approach of adjusting the time-compression of the speech. Design: Experiment 1 measured performance-intensity functions in both a steady speech-shaped noise masker and a 10-Hz square-wave modulated masker. Experiment 2 measured speech-to-masker ratios at threshold as a function of time-compression of the speech (0, 33, and 50%) in both maskers. Study sample: Participants were normal-hearing adults who were native speakers of Brazilian Portuguese (Experiment 1: N = 10; Experiment 2: N = 30). Results: The slope of the performance-intensity function was shallower in the modulated masker than in the steady masker for both words and sentences. Thresholds increased with increasing time-compression in both maskers, but more markedly in the modulated masker, resulting in reduced modulation masking release with increasing time-compression. Conclusions: Speech-to-masker ratio at threshold varies with time-compression of speech. The results are relevant to the issue of whether degree of masker modulation benefit depends on speech-to-masker ratio at threshold.  相似文献   
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