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71.
To estimate the incidence (any mother to child) and rate (from seropositive mother to child) of mother-to-child transmission of Trypanosoma cruzi, a serological census was conducted, targeting pregnant women and infants born to seropositive mothers, in four municipalities of El Salvador. Of 943 pregnant women, 36 (3.8%) were seropositive for T. cruzi. Of 36, 32 proceeded to serological tests of their infants when they became 6–8 months of age. Six infants seropositive at the age of 6–8 months further proceeded to second-stage serological test at the age of 9–16 months. As the result, one infant was congenitally infected. Thus, serological tests at the age of 6–8 months produced five false positives. To ensure earlier effective medication only for true positives, identification of seropositive infants at the age of 9–16 months is crucial. Incidence and rate of mother-to-child transmission were 0.14 (per 100 person-years) and 4.0%, respectively. Estimated number of children infected through mother-to-child transmission in El Salvador (170 per year) was much higher than that of human immunodeficiency virus (HIV; seven per year). It is recommended that serological testing for T. cruzi be integrated into those for HIV and syphilis as part of antenatal care package.  相似文献   
72.
Background:   Osteoporosis is believed to result from the interaction among multiple environmental and genetic determinants that regulate bone-mineral density (BMD).
Methods:   To investigate a potentially predisposing genetic factor in the onset of osteoporosis, we looked for a possible association between BMD in adult Japanese women and known polymorphisms in the leukemia inhibitory factor receptor gene (LIFR).
Results:   An association analysis of chromosomes from 384 volunteer subjects revealed significant correlation between the −603T > C variant of LIFR and radial BMD ( r  = 0.11, P  = 0.032) in this test population. Comparisons of mean values of adjusted radial BMD among separate genotypic groups implied an allelic dosage effect, because homozygous carriers of T alleles of that SNP had the highest adjusted BMDs (0.403 ± 0.054 g/cm2); women homozygous for the C-allele had the lowest (0.373 ± 0.042 g/cm2), and heterozygous individuals had intermediate scores (0.394 ± 0.056 g/cm2).
Conclusion:   This polymorphism in LIFR may be an important determinant of predisposition to postmenopausal osteoporosis.  相似文献   
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Little is known about how beliefs about heredity as a cause of health conditions might influence preventive and interpersonal behaviors among those individuals with low genetic and health literacy. We explored causal beliefs about podoconiosis, a neglected tropical disease (NTD) endemic in Ethiopia. Podoconiosis clusters in families but can be prevented if individuals at genetically high risk wear shoes consistently. Adults (N = 242) from four rural Ethiopian communities participated in qualitative assessments of beliefs about the causes of podoconiosis. Heredity was commonly mentioned, with heredity being perceived as (1) the sole cause of podoconiosis, (2) not a causal factor, or (3) one of multiple causes. These beliefs influenced the perceived controllability of podoconiosis and in turn, whether individuals endorsed preventive and interpersonal stigmatizing behaviors. Culturally informed education programs that increase the perceived controllability of stigmatized hereditary health conditions like podoconiosis have promise for increasing preventive behaviors and reducing interpersonal stigma.  相似文献   
75.
Timely and efficient information transfer at synapses is fundamental to brain function. Synapses are highly dynamic structures that exhibit long-lasting activity-dependent alterations to their structure and transmission efficiency, a phenomenon termed synaptic plasticity. These changes, which occur through alterations in presynaptic release or in the trafficking of postsynaptic receptor proteins, underpin the formation and stabilisation of neural circuits during brain development, and encode, process and store information essential for learning, memory and cognition. In recent years, it has emerged that the ubiquitin-like posttranslational modification SUMOylation is an important mediator of several aspects of neuronal and synaptic function. Through orchestrating synapse formation, presynaptic release and the trafficking of postsynaptic receptor proteins during forms of synaptic plasticity such as long-term potentiation, long-term depression and homeostatic scaling, SUMOylation is being increasingly appreciated to play a central role in neurotransmission. In this review, we outline key discoveries in this relatively new field, provide an update on recent progress regarding the targets and consequences of protein SUMOylation in synaptic function and plasticity, and highlight key outstanding questions regarding the roles of protein SUMOylation in the brain.  相似文献   
76.
Here, we show that overexpression of fer tyrosine kinase (FER), a non-receptor tyrosine kinase, predicts poor postoperative outcome and might be involved in cancer-cell survival in non-small cell lung cancer (NSCLC). Systematic screening using in silico analyses and quantitative RT-PCR revealed that FER was overexpressed in about 10% of NSCLC patients. Evaluation of FER expression using immunohistochemistry (IHC) on tissue microarrays was consistent with the mRNA level detected using quantitative RT-PCR. In analyses of 135 NSCLC patients who had undergone potential curative resection, we found that FER overexpression detected using IHC had no association with clinicopathological features such as age, sex, smoking history, histological type, disease stage, T factor, N factor, adjuvant chemotherapy history, or EGFR mutation, but was correlated with poor postoperative survival periods. A multivariate Cox regression analysis showed that this prognostic impact was independent of other clinicopathological features. In functional analyses of FER in vitro, FER exhibited a transforming activity, suggesting that it possesses oncogenic functions. We also found that human lung cancer NCI-H661 cells, which exhibited FER-outlier expression, were led to apoptosis by the knockdown of FER using RNA interference. FER overexpression might serve as a prognostic biomarker and be involved in cancer-cell survival in NSCLC.  相似文献   
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The T315I BCR-ABL mutation in chronic myelogenous leukemia (CML) patients is responsible for up to 20% of all clinically observed resistance. This mutation confers resistance not only to imatinib, but also to second-generation BCR-ABL tyrosine kinases, such as nilotinib and dasatinib. A number of strategies have been implemented to overcome this resistance, but allogeneic stem cell transplantation remains the only established therapeutic option for a cure. A 61-year-old male was diagnosed with Philadelphia chromosome-positive chronic-phase CML in 2002. He was initially treated with imatinib and complete cytogenetic response (CCyR) was achieved 12 months later. However, after 18 months, a loss of CCyR was observed and a molecular study at 24 months revealed a T315I mutation of the BCR-ABL gene. At 30 months, imatinib/interferon-alfa (IFNα) combination therapy was initiated in an effort to overcome the resistance. Thirty months later, he re-achieved CCyR, and the T315I BCR-ABL mutation disappeared at 51 months. To our knowledge, this is the first case report showing the effectiveness of imatinib/IFNα combination therapy for CML patients bearing the T315I BCR-ABL mutation.  相似文献   
80.

Background

Venous malformations (VM) of lower extremities have characteristic symptoms, especially swelling, pain at rest or with dependence, or in the morning, or with exertion. Sclerotherapy has been applied and has been showed to alleviate the associated signs and symptoms. The aim of this study is to evaluate the outcomes of ethanol sclerotherapy for VM of lower extremities.

Methods

The 21 patients of intramuscular VM of the lower extremities, who received percutaneous sclerotherapy using absolute ethanol in our institute, were reviewed retrospectively. The average age at the time of the initial diagnosis was 18.6 years, and average follow-up period after last sclerotherapy is 19.4?±?13.5 months. The postinterventional changes of the associated signs and symptoms were evaluated by utilizing original VM scoring system.

Results

The average number of sclerotherapy sessions was 2.6 times per case. The average total amount of ethanol used in each patient was 41.3 ml. Sclerotherapy reduced the associated signs and symptoms in many of the patients (n?=?19/21). Preinterventional VM score as the overall baseline status was 10, and the average VM score after sclerotherapy was 4.1. There was no inverse correlation between the amount of ethanol used and the VM score. In seven cases treated more than three times, reverse correlation between the “VM score” and the number of sclerotherapy sessions was demonstrated (p?<?0.05, ρ?=?0.8214).

Conclusions

The characteristic symptoms and signs of the VM were improved by sclerotherapy. More than three sessions of ethanol sclerotherapy improved the overall status of extensive intramuscular VM in lower extremities. Level of Evidence: Level IV, therapeutic study.  相似文献   
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