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61.
BACKGROUND: Changes in epithelial cell interactions have been implicated in carcinogenesis, tumour invasion and metastasis. AIM: To screen for altered expression of epithelial adhesion genes in lung cancer development. METHODS: Gene expression profiles were assessed with cDNA expression arrays in eight non-small cell lung cancer (NSCLC) and eight normal bronchi obtained from the same patient. Immunohistochemistry (IHC) and RNA in situ hybridisation (ISH) were used to confirm the most prominently expressed adhesion molecules and to investigate their distribution at protein and mRNA levels. RESULTS: 43 differentially expressed cancer-related genes were identified in adenocarcinoma, squamous cell carcinoma (SCC) and normal bronchus. Five of these genes are related to epithelial adhesion-that is, integrin alpha3 (ITGA3), integrin beta4 (ITGB4), desmoplakin I and II (DSP), plakoglobin, and desmocollin 3 (DSC3). ITGA3 and ITGB4, showing predominantly cell-matrix staining, were up regulated in adenocarcinoma and SCC, respectively. ITGB4 also showed strong staining in SCC with IHC and ISH. Components of the desmosome adhesion complex DSP, plakoglobin and DSC3 were strongly up regulated in SCC and showed a distinct cell-cell staining pattern. DSP and plakoglobin were predominantly present at central, more differentiated tumour cells, whereas DSC3 showed a stronger staining in the peripheral basal cells of SCC tumour areas. CONCLUSIONS: Lack of cellular adhesion may have an important role in the metastatic potency of a primary tumour. A possible association of strong presence and normal-distributed desmosomal molecules in SCC with the less frequent and late pattern of metastasis in SCC as compared with adenocarcinoma is suggested.  相似文献   
62.
Cross-species transmission has been shown to play an important role in the emergence of human retroviruses. We developed a generic enzyme immunoassay using synthetic peptides from gp41 and C2V3 consensus sequences (human immunodeficiency virus [HIV] type 1 [HIV-1] groups M, O, and N and the homologous region of simian immunodeficiency virus [SIV] strains from chimpanzees [SIVcpz], SIVcpzGAB1 and SIVcpzANT) to detect divergent HIV and SIV. A cocktail of peptides from gp41 and C2V3 (M-O) detected all HIV-1 group M and O sera and showed cross-reactivity with SIVcpz sera. Further, a mixture of C2V3 peptides (GAB1-ANT) failed to detect HIV-1 infections but reacted with all SIVcpz sera, allowing discrimination of SIVcpz from HIV-1 infections. Since most SIVcpz sera cross-reacted with HIV-1 peptides, we next evaluated SIVcpz serum reactivity with rapid tests for HIV-1/2. SIVcpzANT and SIVcpzUS sera reacted with the Sero-strip and Multispot assays. Both tests are sensitive in detecting group M (97 100%, respectively), although Multispot has lower sensitivity for group O detection (67%) than does Sero-strip (100%). The limited volume and time required to perform these assays make them a generic tool for field screening. The env peptide-based assay and rapid tests should allow for the identification of emerging variants of HIV and SIV.  相似文献   
63.
ObjectiveThis study aimed to investigate sex differences in the temporal dynamics of experiencing empathy by using electrophysiological measurements.MethodsTwenty-five females and 27 males viewed 414 pictures of the International affective picture system varying in emotional valence (positive, negative and neutral) and presence of humans (human and scenes). EEG event related potentials (ERPs) were obtained and correlations were computed with self-reported empathy.ResultsCompared to males, females showed increased anterior N2 and parietal LPP amplitudes to humans contrasted with scenes (independent of emotional valence) and to negative contrasted with neutral emotions (independent of human presence). Independent of sex the N1 and anterior N2 were specifically increased for positive human emotions and the parietal LPP for negative human emotions. Across sexes, the N2 and LPP human emotion effects and LPP human effects were associated with self-reported affective empathy, but not with cognitive empathy.ConclusionsThis study provides electrophysiological evidence that women prioritize the processing of socially relevant and negative emotional information, but that women did not show enhanced brain potentials to pictures with positive or negative emotions in humans.  相似文献   
64.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
65.
Grüntzig balloon catheters were used to dilate ten esophageal strictures in eight infants and children. Five infants who had anastomotic strictures following esophageal atresia repair gained complete resolution of their strictures, usually after one or two dilatations. Three older children who had strictures following esophageal re-operation or reconstruction required longer courses of dilatations to achieve consistent esophageal patency. The technique failed in two chronic strictures of two and one-half and nine years' duration. Balloon catheter dilatation, begun in the early postoperative period, is a safe, effective method for dilating esophageal strictures.  相似文献   
66.

Background

Axillary lymph node dissection (ALND) is frequently performed for node-positive (cN+) breast cancer patients. Combining positron emission tomography/computed tomography (PET/CT) before-NST and the MARI (marking axillary lymph nodes with radioactive iodine seeds) procedure after neoadjuvant systemic therapy (NST) has the potential for avoiding unnecessary ALNDs. This report presents the results from implementation of this strategy.

Methods

All breast cancer patients treated with NST at the Netherlands Cancer Institute who underwent a PET/CT and the MARI procedure from July 2014 to July 2017 were included in the study. All the patients underwent tailored axillary treatment according to a protocol based on the combined results of PET/CT before NST and the MARI procedure after NST. With this protocol, patients showing one to three FDG-avid axillary lymph nodes (ALNs) on PET/CT (cN<4) and a tumor-negative MARI node receive no further axillary treatment. All cN (<4) patients with a tumor-positive MARI node receive locoregional radiotherapy, as well as patients with four or more FDG-avid ALNs [cN(4+)] and a tumor-negative MARI node after NST. An ALND is performed only for cN(4+) patients with a tumor-positive MARI node.

Results

The data of 159 patients who received a PET/CT before NST and a MARI procedure after NST were analyzed. Of these patients, 110 had one to three FDG-avid ALNs and 49 patients showed four or more FDG-avid ALNs on PET/CT before NST. For 130 patients (82%), ALND was omitted. Locoregional radiotherapy was administered to 91 patients (57%), and 39 patients (25%) received no further axillary treatment.

Conclusion

Combining pre-NST axillary staging with PET/CT and post-NST staging with the MARI procedure resulted in an 82% reduction of ALNDs for cN?+?breast cancer patients.
  相似文献   
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69.
OBJECTIVE: To compare changes in regional cerebral blood flow (rCBF), using positron emission tomography (PET), during chronic and acute sacral neuromodulation (SN). SN is an effective long-term treatment for chronic urge incontinence due to urinary bladder hyperactivity, as sensory nerves, spinal and supraspinal structures are probably responsible for the action of SN. It is not known which brain areas are involved, and the optimum benefit of SN is not immediate, suggesting that induced plasticity of the brain is necessary. PATIENTS AND METHODS: Brain activity was measured in two groups: 12 urge incontinent patients (11 women and one man; mean age 52 years) in whom an implanted unilateral S3 nerve neurostimulator had been effective for >6 months (mean time after implantation 4.5 years); and eight urge incontinent patients (seven women and one man; mean age 49 years) in whom the neurostimulator was activated for the first time in the PET scanner. RESULTS: During SN in chronically implanted patients, there were significant decreases in rCBF in the middle part of the cingulate gyrus, the ventromedial orbitofrontal cortex, midbrain and adjacent midline thalamus, and rCBF increases in the dorsolateral prefrontal cortex. During acute SN in newly implanted patients, there were significant decreases in rCBF the medial cerebellum, and increases in the right postcentral gyrus cortex, the right insular cortex and the ventromedial orbitofrontal cortex. Group analysis between chronic and newly implanted patients showed significant differences in the associative sensory cortex, premotor cortex and the cerebellum, all three involved in learning behaviour. CONCLUSIONS: These findings suggests that chronic SN influences, presumably via the spinal cord, brain areas previously implicated in detrusor hyperactivity, awareness of bladder filling, the urge to void and the timing of micturition. Furthermore, SN affects areas involved in alertness and awareness. Acute SN modulates predominantly areas involved in sensorimotor learning, which might become less active during the course of chronic SN.  相似文献   
70.
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