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971.
A review of 167 cases of esophageal carcinoma without preoperative treatment revealed 24 (14.4%) to have intramural metastasis (IM) within the esophagus. Among the clinicopathologic factors, the length of the lesions (P < 0.01), lymph node metastasis (P < 0.001), and the depth of the invasion of the tumor (P < 0.0001) were found to be statistically significant different factors between the two groups of patients both with and without intramural metastasis. The survival curve for patients with IM was significantly lower than that for patients without IM (P < 0.0001). A univariate analysis revealed that the depth of invasion, lymph node metastasis, IM (P < 0.0001), and the length of the lesion (P < 0.001) all had a significant correlation with the prognosis. Moreover, in a multivariate analysis, the depth of the invasion (<0.001), length of the lesion (0.001), and IM (0.049) were all determined to be significant prognostic factors. Therefore, IM is considered to be one of the independent significant prognostic factors for predicting a poor prognosis in esophageal cancer. © 1994 Wiley-Liss, Inc.  相似文献   
972.
The multidrug-resistance phenotype in human tumors is partly associated with over-expression of the 170 kDa-P-glycoprotein encoded by the multidrug-resistance-1 (MDRI) gene. Another related, but non-P-glycoprotein, multidrug-resistance-associated protein (MRP) gene encodes a 190 kDa membrane ATP-binding protein. Glioblastoma multiforme is a highly malignant primary neoplasm of the central nervous system which is refractory to anti-cancer chemotherapy, but the mechanism underlying this drug resistance is unknown. Out of glioma cell lines, 2, namely IN500 and T98G, which had elevated MRP mRNA levels, showed the highest resistance to multiple anti-cancer agents such as etoposide, vincristine and adriamycin, and decreased intracellular accumulation of etoposide. In the remaining 5 cell lines, various degrees of sensitivity to adriamycin and etoposide appeared to correlate with their respective MRP mRNA levels. Our study proposes that MRP may be involved in spontaneous multidrug resistance in human gliomas.  相似文献   
973.
974.
A 10-month-old girl with mild developmental delay became hemiplegic after seizures. Cranial CT scan and magnetic resonance imaging (MRI) revealed no lesions related to vascular diseases, but brain atrophy on the right side was remarkable. Digital subtraction angiography showed slightly decreased visualization of peripheral branches of the right medial cerebral artery. Propionic acidaemia was diagnosed on the basis of high plasma levels of propionic acid and its metabolites and the elevated urinary excretion of these acids. With therapy, the levels of these acids fell, and her left hemiplegia disappeared 3 months later.  相似文献   
975.
Using a newly developed injection technique, the absorption of horseradish peroxidase (HRP) in the endolymphatic sac (ES) of the guinea pig was examined by light and electron microscopy. HRP (molecular weight: 40,000; molecular diameter: about 5-nm) was directly injected into the lumen of the ES by electrophoresis after the recording of a direct current potential in the ES lumen. Both the macrophages floating in the ES lumen and the epithelial cells in the intermediate portion of the ES absorbed intraluminal HRP. The macrophages internalized the intraluminal HRP at a higher rate than the epithelial cells, suggesting that macrophages play a major role in macromolecular absorption in the ES. It was considered that the macrophages took up intraluminal HRP by phagocytosis, while the epithelial cells of the intermediate portion took it up by pinocytosis. In contrast, the epithelial cells in the proximal portion of the ES absorbed little HRP. No penetration through the junctional complexes between epithelial cells was observed in either the intermediate or the proximal portion at any interval after the injection of HRP. This finding indicates that these junctional complexes are impermeable to intraluminal HRP.  相似文献   
976.
We present the case of a 6-year-old boy who had an omphalocele repaired at day 1 of life. He had a secundum atrial septal defect and an anomalous inferior vena cava of a type which has not been previously reported. Cine-MRI was a useful noninvasive tool for diagnosing the anomalous subaortic innominate vein and four immature vessels which make up the venous drainage systems of the lumbar region. The recognition of this malformation is important in planning and executing surgical repair or cardiac catheterization for postoperative patients with omphaloceles.  相似文献   
977.
To elucidate whether common genetic events in human urinarybladder carcinogenesis also occur in rodent models, we investigatedthe presence of p53, H- and K-ras mutations in 18 urinary bladdercarcinomas induced by various concentrations of N-butyl-N-(4-hydroxybutyl)nitrosamine(BBN) in male NON/Shi mice. Histopathologically, all were invasive,11 being squamous cell carcinomas (SCCs) and the remaining sevenbeing transitional cell carcinomas (TCCs). Using polymerasechain reaction single-strand conformation polymorphism (PCR-SSCP)analysis followed by DNA sequencing, p53, H- and K-ras mutationswere observed in 14 (78%; exons 5–7), two (11%; one eachon exons 1 and 2) and one (5.6%; exon 1) animals respectively.The frequencies of mutations in p53 exons 5, 6 and 7 were 7(39%), 4 (22%), and 9 (50%) respectively, and no mutation wasfound in exon 8. All mutations involved one base-pair substitutionwith or without amino acid changes and the types of base-pairsubstitution were random. No evident association was observedbetween mutation sites and the histological phenotypes. In conclusion,p53 mutations are frequent in BBN-induced mouse invasive urinarybladder tumors, at similar levels to those observed for humanhigh-grade invasive carcinomas, and this plus their distributionsuggests their possible participation in this model of urinarybladder carcinogenesis.  相似文献   
978.
Initiation activities of endogenously formed N-nitrosobis(2-hydroxypropyl)amine(NBHPA), N-nitrosodiethanolamine (NDELA) and N-nitroso-2,6-dimethylmorpholine(NDMM) were investigated in a modified short-term assay forrat hepatocarcinogenesis. Male Wistar rats were fed 1 % bis(2-hydroxypropyl)amine,0.5% diethanolamine or 0.25% 2,6-dimethylmorpholine in the dietplus 0.3% sodium nitrite in the drinking water. Two weeks afterstarting the experimental regimen they underwent 2/3 partialhepatectomy and were then maintained on the respective dietsfor a further week. Following a 2 week recovery period on basaldiet the rats were subjected to a resistant hepatocyte regimenconsisting of 0.02% 2-acetylaminofluorene in the diet for 2weeks and 1 mg carbon tetrachloride/kg body wt by gavage atthe midpoint. Initiation activity was assayed by measuring hepaticfoci positive for  相似文献   
979.
False negative rates were compared in two screening modalities, physical examination with or without mammography, in an intervention study for women aged over 50 in Miyagi Prefecture. Thirty-five breast cancers were detected in 12,515 subjects who participated in the trial consisting of physical examination and mammography, whereas 44 breast cancers were detected in 50,105 subjects who received physical examination alone, so that the detection rates were 0.28% and 0.09%, respectively. Among 50,061 subjects who received physical examination alone, 8 women were diagnosed as having breast cancer within 12 months after the screening, while only one of 12,480 screenees receiving the combined modality was so diagnosed, implying false negative rates of 15.4% and 2.8%, respectively. When the screening sensitivity in the combined system was analyzed according to each single modality, the false negative rate provided by physical examination with mammography turned out to be 2.8%, significantly lower than that (33.3%) by the physical examination alone. Minimal breast cancers represented 25.7% of all screen-detected cancers in the combined modality, compared with 9.1% in the modality without mammography. The trial thus indicates that physical examination combined with mammography may be an appropriate modality for breast cancer screening in women aged over 50 on the basis of screening sensitivity.  相似文献   
980.
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