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Phase II Study of Mitoxantrone in Patients With Non-Small Cell Lung Cancer   总被引:1,自引:0,他引:1  
A phase II study of mitoxantrone was performed in 24 patientswith non-small cell lung cancer (NSCLC). Mitoxantrone was administeredby intravenous drip infusion of 12 mg/m2 every three weeks.There were no responders among the 21 evaluable patients includingfive patients without prior therapy. The major hematologicaltoxic effect was leukocytopenia. Thrombocytopenia and decreasein hemoglobin were slight. A change in the electrocardiogramwas observed in one patient and one patient experienced cardiogenicshock. Mitoxantrone is not acceptable for the treatment of NSCLC becauseof its low antitumor activity, and careful observation is neededfor administration of this agent to patients with pre-existingrisk factors, such as prior anthracycline exposure, mediastinalradiation or underlying cardiovascular disease.  相似文献   
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MRI of ossification of ligamentum flavum.   总被引:11,自引:0,他引:11  
Magnetic resonance imaging of 28 patients with radiological and/or histopathologically proved ossification of the ligamentum flavum (OLF) was reviewed. The locations of OLF were cervical (n = 4), thoracic (n = 22), and lumbar (n = 2). On T1- and T2-weighted images, OLF demonstrated low signal intensity. Areas of high or intermediate signal intensity within the OLF on T1-weighted images were observed in three cases and were interpreted to be due to fat infiltration. In six cases, high intensity areas in the spinal cord caused by compressing OLF were demonstrated on T2-weighted images. Gadolinium-diethylenetriamine pentaacetic acid, which was used in four cases, showed cord enhancement at the level of compression by OLF in three cases.  相似文献   
5.
To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.  相似文献   
6.
Patients with Peutz-Jeghers syndrome (PJS) are known to be at risk of gastric cancer (GC), and the STK11 gene is a susceptibility gene for PJS. However, as no cases of PJS with GC in which a STK11 germline mutation has been identified have ever been reported and other susceptibility genes have also been suggested to be involved in PJS, the relation between STK11 germline mutations and GC in PJS is still unknown. In this study, we used sequencing analysis to investigate the STK11, CDH1, and TP53 loci for a germline mutation in two siblings with PJS with primary GC. A novel type of the STK11 germline mutation, c.890delG, encoding a truncated protein (p.Arg297fsX38) was identified, but no germline mutations of the CDH1 and TP53 genes were detected. No inactivation of the wild-type allele by somatic mutation or chromosomal deletion or hypermethylation at the 5'-CpG site of STK11 was detected in the GC. This is the first report of a STK11 germline mutation in a PJS patient with GC and should contribute to establishing correlations between the STK11 germline mutations and GC in PJS patients.  相似文献   
7.
Gastrointestinal tract tumours are notorious for their difficulty in relation to conventional cytogenetic analysis. In particular, necrosis, the presence of stromal inflammatory and other cells, and poor attachment of tumour cells have led to problems with the quality and reliability of cytogenetic preparations, even with the recently developed fluorescence in situ hybridisation (FISH) technique. Furthermore, background autofluorescence masks the weak hybridisation signals in the nuclei. To overcome this problem, brief microwave treatment was applied for the identification of centromeres by in situ hybridisation in gastric cancer cells. Using this technique, a panel of 17 centromeric specific alpha-satellite probes was used to detect chromosomal instability in these cells. Lymphocyte controls and cancer cells subjected to irradiation achieved the hybridisation threshold in 30 minutes, providing a significant difference when compared with the non-irradiated samples (mean (SD) frequency of diploid cells 97% (2.1%) v 76% (4.6%), respectively). Therefore, this protocol of intermittent microwave treatment is recommended as a simple, rapid, and highly reproducible technique for application to various types of probe. It also gives well defined hybridisation signals and reduces background "noise".  相似文献   
8.
Activation of Rac1 by a Crk SH3-binding protein, DOCK180   总被引:16,自引:1,他引:16       下载免费PDF全文
DOCK180 is involved in integrin signaling through CrkII-p130Cas complexes. We have studied the involvement of DOCK180 in Rac1 signaling cascades. DOCK180 activated JNK in a manner dependent on Rac1, Cdc42Hs, and SEK, and overexpression of DOCK180 increased the amount of GTP-bound Rac1 in 293T cells. Coexpression of CrkII and p130Cas enhanced this DOCK180-dependent activation of Rac1. Furthermore, we observed direct binding of DOCK180 to Rac1, but not to RhoA or Cdc42Hs. Dominant-negative Rac1 suppressed DOCK180-induced membrane spreading. These results strongly suggest that DOCK180 is a novel activator of Rac1 and involved in integrin signaling.  相似文献   
9.
Adjuvant and antitumor activities of synthetic 6-O-"mycoloyl"-N-acetylmuramyl-L-alanyl-D-isoglutamine were examined. All the synthetic 6-O-corynomycoloyl-, 6-O-mocardomycoloyl-, and 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine were active as adjuvants for cell-mediated immune responses. However, 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine was less active as an adjuvant on circulating antibody formation. It was shown that pyrogenic activity of N-acetylmuramyldipeptide was reduced by 6-O-acylation with mycolic acid, but not with nocardomycolic or corynomycolic acid. Tumor-suppression activity was observed by the synthetic 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine by using transplantable tumor in syngenic mice.  相似文献   
10.
The existence of a mycoplasmal arginine deiminase which catalyzes the conversion of L-arginine to L-citrulline has been postulated. Here we show the partial amino acid sequence of arginine deiminase of Mycoplasma arginini and the complete nucleotide sequence of the arginine deiminase gene of M. arginini. The open reading frame deduced from this sequence consists of 1,230 bp encoding 410 amino acids. The mature form of this enzyme contains 409 amino acids after the deletion of the first methionine. In this open reading frame, TGA nonsense codons are used as tryptophan codons; this usage was verified by determination of the amino acid sequence. The molecular weight of the enzyme calculated from the deduced amino acid sequence is 46,372. Recently, the nucleotide sequence of the arginine deiminase gene of M. arginini was reported by Kondo et al. (K. Kondo, H. Sone, H. Yoshida, T. Toida, K. Kanatani, Y.-M. Hong N. Nishino, and J. Tanaka, Mol. Gen. Genet. 221:81-86, 1990). However, their sequence differed from ours in several places and especially at the C terminus.  相似文献   
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