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We present a case of spinal cord sarcoidosis which resembled a disseminated intramedullary tumour. The case is unusual because the spinal cord is only rarely affected by sarcoidosis and the patient developed a neurological deficit as the first manifestation of the disease. This condition thus has to be considered in the differential diagnosis of primary intramedullary tumours, or metastatic disease with involvement of the spinal cord.  相似文献   
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Bilateral facial palsy is frequently linked with lyme disease. We report a patient with bilateral facial palsy due to Epstein-Barr virus infection but with Borrelia burgdorferi IgM in serum caused by polyclonal B-lymphocyte stimulation.  相似文献   
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Summary The wobbler mutation is inherited as an autosomal recessive trait and displays a muscular atrophy associated with motoneuron degeneration in early postnatal development. It has been shown that the level of glial fibrillary acidic protein (GFAP) is greatly increased in the spinal cord of wobbler mice. We performed immunocytochemical analyses combined with confocal microscopy to study the developmental distribution of GFAP-positive astrocytes in the spinal cord of wobbler mice during the course of the disease, and in primary cultures of adult wobbler spinal cord astrocytes. Many changes in the number and distribution of astrocytes were observed in the wobbler mice from 1–10 months post-partum. Strongly GFAP-positive astrocytes are present in small number in the anterior horn by 1 month. They increase in number and are observed in the entire spinal cord grey and white matters by 2–10 months. These reactive astrocytes have thick, short, extensively branched processes which contrast with the long, unbranched processes observed in control mice. The wobbler astrocyte processes are oriented perpendicular to the surface of the spinal cord, which contrasts with the normal parallel, concentric orientation. No expansion of astrocyte processes exit from the white matter towards the grey matter. Moreover, the surface of the wobbler spinal cord beneath the meninges displays a dramatic decrease of interdigitating processes, end feet and flattened cell bodies of astrocytes that form a disorganized layer.In vitro, mutant astrocytes have morphological characteristics similar to thosein vivo and, in particular, develop short, thick, branched processes. These mutant astrocytes in cultures do not contact one another, whereas normal mature cultures show an increased incidence of cell-cell contacts between long processes. The increase of astrocyte reactivity associated with these modifications in astrocytic process arrangement may reflect an important primary event in the course of the wobbler disease rather than a non-specific response to motoneuronal death.  相似文献   
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The prevalence of recently described mutation V176F, located in the beginning of the rpoB gene and associated with rifampin resistance and the wild-type cluster I sequence, was determined by analyzing the distribution of rpoB mutations among 80 rifampin (RIF)-resistant Mycobacterium tuberculosis strains isolated in Germany during 1997. The most frequent rpoB mutations were changes in codon 456 (52 isolates, 65%), followed by changes in codon 441 (13 isolates, 16%) and codon 451 (11 isolates, 14%). The V176F mutation was detected in one isolate of the study population and in 5 of 18 RIF-resistant strains with no cluster I mutation from six previously published studies. In three isolates, a mixture of resistant and susceptible subpopulations (heteroresistance) prohibited the detection of rpoB mutations in the initial analysis; however, in these isolates, cluster I mutations could be verified after a passage on RIF-containing medium. IS6110 DNA fingerprinting of 76 strains revealed eight clusters comprising 27 strains with identical restriction fragment length polymorphism patterns that mainly also show identical rpoB mutations and identical or similar drug resistance patterns. In conclusion, our results indicate that the V176F mutation should be included in molecular tests for prediction of RIF resistance in M. tuberculosis. We further demonstrated that heteroresistance caused by a mixture of mycobacterial subpopulations with different susceptibilities to RIF may influence the sensitivity of molecular tests for detection of resistance.  相似文献   
7.
Following denervation of adult muscle, levels of acetylcholine receptor (AChR) increase; normal, low levels are restored only after muscle reinnervation. After neonatal denervation, we found a large initial increase in AChR levels during the first days postsurgery, as in adult denervated muscle. However, 1 week after denervation, total AChR levels decreased in the absence of any sign of reinnervation. By 3 weeks after surgery, near-normal levels of AChR were restored and extrajunctional AChR had disappeared. Thus, in sharp contrast to adult muscle, in young denervated muscle a down-regulation of AChR occurs without recovery of innervation and normal muscle contractile activity. These results suggest that different mechanisms regulate the levels of AChR in developing and adult skeletal muscle.  相似文献   
8.
Secretory immunoglobulin A (SIgA) anti-casein and SIgA anti-beta-lactoglobulin (BLG) were determined in the saliva of 158 healthy mature infants at birth and in breast milk samples using a direct Elisa technique. IgG anti-casein and anti-BLG were measured in serum samples from mothers and newborns (cord blood). A high risk of allergy was defined in 66 infants who had cord blood (CB)-IgE levels greater than or equal to 0.9 IU/ml and/or parents with atopic diseases. Thirty infants had CB levels less than 0.9 IU/ml and parents without clinical symptoms of atopy but with elevated serum IgE concentrations or type I skin reactions to common allergens (low risk). Sixty-two infants had CB-IgE levels less than 0.9 IU/ml and healthy parents (no risk). The groups were matched for social status, smoking and dietary habits. SIgA anti-casein and anti-BLG were detected in all newborns. SIgA anti-casein was significantly higher (p less than 0.05) in high risk infants (medium 157; 50% confidence limits 45-270) than in no risk (48; 25-150) or low risk infants (43; 21-130). SIgA anti-casein values correlated with maternal allergy, maternal allergy plus CB-IgE, but not with paternal allergy. Breast milk SIgA anti-BLG was depressed (p less than 0.05) in mothers with manifest allergy compared to healthy mothers. Determination of salivary SIgA anti-casein may represent an additional screening method for early detection of infants with atopic disposition.  相似文献   
9.
Research has indicated that performance on heartbeat counting tasks may be influenced by beliefs about heart rate. Sixty male subjects were administered the Schandry heartbeat counting task after viewing fast, slow, or no heart rate feedback. Subjects were also administered the Whitehead signal-detection type task. Results indicated that subjects who received fast or no heartbeat feedback performed better on the Schandry task than subjects who received slow feedback. Feedback presentation did not affect performance on the Whitehead task. These results suggest that the Schandry task is influenced by external variables (expectations, beliefs) beyond pure awareness of "discrete" visceral sensations and, thus, may not be as powerful a method for determining awareness of individual heartbeats as some other paradigms.  相似文献   
10.
Summary Immunotherapy using bacille Calmette-Guérin (BCG) has gained increasing acceptance in the management of superficial bladder cancer. Systemic reactions after intravesical instillation of BCG are rare. However, when the therapy is complicated, the lung often becomes involved. Since the pathogenesis of lung infiltrates after immunotherapy is unknown, we report on a patient who developed a lung infiltrate after receiving BCG immunotherapy for bladder cancer. The infectious etiology was established by culture confirmation of a BCG strain in the broncheoalveolar lavage fluid.Abbreviation BCG bacille Calmette-Guérin  相似文献   
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