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1.
Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyroluspreserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system.  相似文献   
2.
NUMB and NUMBL are implicated in cell fate determination through the inhibition of Notch signaling. LNX, binding to NUMB and CXADR (CAR), functions as E3 ubiquitin ligase at least for NUMB. LNX is the paralog of PDZRN1 (PDZ domain containing RING finger 1). Here, we identified two novel homologs of LNX and PDZRN1 by using bioinformatics, which were designated PDZRN3 (LNX3 or SEMCAP3) and PDZRN4 (LNX4 or SAMCAP3L), respectively. KIAA1095 cDNA (AB029018) was the representative PDZRN3 cDNA. Complete coding sequence of PDZRN4 cDNA was determined by assembling nucleotide sequences of ESTs (BF059062 and AW297403), FLJ33777 cDNA (AK091096) and IMAGE5767589 cDNA (BC040922). PDZRN4 gene, consisting of 11 exons, was found to encode two isoforms with N-terminal divergence (PDZRN4 and PDZRN4S) due to an alternative promoter. PDZRN3-CNTN3 locus at human chromosome 3p13-p12.3 and PDZRN4-CNTN1 locus at human chromosome 12q12 were paralogous regions within the human genome. PDZRN3 (1066 aa) and PDZRN4 (1036 aa) showed 59.9% total-amino-acid identity. Two bipartite nuclear localization signals (NLS) were located within the C-terminal region of PDZRN3 and PDZRN4. PR34H1 and PR34H2 domains were identified as the regions conserved among PDZRN3, PDZRN4 and Drosophila CG1783. PDZRN3 and PDZRN4 consist of RING, two PDZ, PR34H1, PR34H2 domains and two NLS, while PDZRN1 and LNX consist of RING and four PDZ domains. PDZRN family proteins were classified into the LNX-PDZRN1 subfamily and the PDZRN3-PDZRN4 subfamily. This is the first report on the PDZRN3 and PDZRN4 genes.  相似文献   
3.
Array CGH combined with mRNA microarray analyses was successfully applied for genome-wide screening of proto-oncogenes and tumor suppressor genes in 2002. The CCND1-ORAOV1-FGF19-FGF4-FGF3-FLJ10261-FADD-PPFIA1-EMS1 locus on human chromosome 11q13 is one of the most frequently amplified regions within the human genome. Here, we identified and characterized mouse Ppfia1 gene by using bioinformatics. Nucleotide sequence of mouse Ppfia1 cDNA was determined in silico by assembling nucleotide sequences of ESTs BY727670, CA327608, BU708520, BQ886535, and a 5'-truncated partial cDNA BC038349. Mouse Ppfia1 gene, consisting of 28 exons, was located between Fadd and Ems1 (also known as Cttn) genes on mouse chromosome 7. Mouse Ppfia1 (1201 aa) and human PPFIA1 (1202 aa), showing 95.8% total-amino-acid identity, were found to consist of MAH (myosin heavy chain tail and ATPase homologous) domain and three SAM (sterile alpha motif) domains. MAH domain is implicated in the homo- or hetero-oligomer formation through the coiled-coil interaction, while SAM domain is implicated in the interaction with other proteins. Mouse Ccnd1-Ems1 locus and human CCND1-EMS1 locus were evolutionarily conserved in the order and the orientation of genes therein. Nucleotide and amino-acid substitution rates of Ccnd1, Ppfia1 and Ems1 genes located near both ends of the Ccnd1-Ems1 locus were relatively lower than those in the middle part of the locus. This is the first report on mouse Ppfia1 gene as well as comprehensive comparison of CCND1-EMS1 locus within the human and mouse genomes.  相似文献   
4.
Activation of the peripheral protease-activated receptor-2 (PAR-2) triggers nociceptive behaviour and thermal hyperalgesia in rats. The present study created a novel mouse model for PAR-2-triggered nociception, and then examined the roles of NMDA receptors and the nitric oxide (NO) pathway in nociceptive processing by PAR-2. Intraplantar administration of the PAR-2 agonist SLIGRL-NH(2) elicited nociceptive responses in mice, an effect being more specific in mast cell-depleted mice. This PAR-2-triggered nociception was abolished by the NMDA receptor antagonist MK-801, but not the neuronal NO synthase inhibitor 7-nitro indazole. In contrast, the PAR-2-triggered thermal hyperalgesia in rats was blocked by both agents. Our study thus provides a novel mouse model for PAR-2-mediated nociception, and suggests that NMDA receptors are involved in PAR-2-triggered nociception and hyperalgesia, while NO contributes only to the latter.  相似文献   
5.
Step-sections of 96 whole kidneys from 50 chronic hemodialysis patients were subjected to a histopathological and quantitative investigation with regard to the development of renal neoplastic lesions. The range of hemodialysis duration was from 1 to 222 months. A total of 349 renal cell adenomas were found in 41 cases (82%). They were commonly multiple and present bilaterally. Renal cell carcinomas were evident in four cases (8%), with hemodialysis durations of 54, 57, 112 and 222 months. The incidence of adenomas increased in a hemodialysis duration-dependent manner, indicating a high risk of renal cell tumor development in chronic hemodialysis patients. Furthermore, acquired cystic disease of the kidney (ACDK) was also observed in 12 cases (24.0%), where the mean hemodialysis period was 143.4 ± 48.0 months. This value was significantly longer than that of non-ACDK cases (P < 0.001). There was, however, no clear relationship between the appearance of ACDK and renal cell tumors. The present results underline the necessity for attention to possible neoplasia of the kidney in patients on long-term hemodialysis.  相似文献   
6.
Mouse Formin (Fmn1) protein plays a key role in limb morphogenesis. Fmn1 is one of the actin regulators with scaffold function, interacting with Profilin, SRC, EMS1, FNBP1, FNBP2, FNBP3, FNBP4, WBP4 and alpha-catenin. Fmn1, Fmn2, FHOD1, FHOD3, GRID2IP and FHDC1 are non-FDD-type Formin homology proteins, while FMNL1, FMNL2, FMNL3, DIAPH1, DIAPH2, DIAPH3, DAAM1 and DAAM2 are FDD-type Formin homology proteins. Here, we identified the human FMN1 gene by using bioinformatics. The complete coding sequence of human FMN1 cDNA was determined by assembling AC055874.8 genome sequence (nucleotide position 178207-180073), AI040235 EST (complementary sequence for nucleotide position 331-156) and FLJ45135 cDNA (nucleotide position 319-3310). FMN1 isoform 1 (exons 1-18) and FMN isoform 2 (exons 1b and 3-18) were transcribed due to alternative splicing of the alternative promoter type. The FMN1 gene at human chromosome 15q13.3 was located between CKTSF1B1 (Gremlin) and RYR3 genes. The Xenopus fmn1 gene was identified within the Xenopus genome sequence CH216-24N20 (AC147835.1). The FMH1 domain (codon 1-120 of FMN1) and FMH2 domain (codon 683-835 of FMN1) were identified as novel regions conserved among human FMN1, mouse Fmn1, and Xenopus fmn1. The FMH2 domain was almost identical to the alpha-catenin binding domain of mouse Fmn1. Human FMN1 (1419 aa), showing 77.1% total amino-acid identity with mouse Fmn1, was found consisting of FMH1, FMH2, FH1 and FH2 domains. This is the first report on the identification and characterization of the human FMN1 gene as well as the FMH1 and FMH2 domains.  相似文献   
7.
The substantia gelatinosa (SG) of the spinal dorsal horn shows significant morphological heterogeneity and receives primary afferent input predominantly from Aδ- and C-fibres. Despite numerous anatomical and physiological studies, correlation between morphology and functional connectivity, particularly in terms of inhibitory inputs, remains elusive. To compare excitatory and inhibitory synaptic inputs on individual SG neurones with morphology, we performed whole-cell recordings with Neurobiotin-filled-pipettes in horizontal slices from adult rat spinal cord with attached dorsal roots. Based on dendritic arborization patterns, four major cell types were confirmed: islet, central, radial and vertical cells. Dorsal root stimulation revealed that each class was associated with characteristic synaptic inputs. Islet and central cells had monosynaptic excitatory inputs exclusively from C-afferents. Islet cells received primary-afferent-evoked inhibitory inputs only from Aδ-fibres, while those of central cells were mediated by both Aδ- and C-fibres. In contrast, radial and vertical cells had monosynaptic excitatory inputs from both Aδ- and C-fibres and inhibitory inputs mediated by both fibre types. We further characterized the neurochemical nature of these inhibitory synaptic inputs. The majority of islet, central and vertical cells exhibited GABAergic inhibitory inputs, while almost all radial cells also possessed glycinergic inputs. The present study demonstrates that SG neurones have distinct patterns of excitatory and inhibitory inputs that are related to their morphology. The neurotransmitters responsible for inhibitory inputs to individual SG neurones are also characteristic for different morphological classes. These results make it possible to identify primary afferent circuits associated with particular types of SG neurone.  相似文献   
8.
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function.  相似文献   
9.
The major pelvic ganglion in both the rat and guinea pig has been extensively studied because of its anatomical simplicity. To clarify the target specific neural pathway in the diffusely distributed pelvic ganglia of larger animals, the pelvic plexus of the female dog was investigated by retrograde tracing and immunohistochemistry. The whole mount staining of the pelvic plexus with acetylcholinesterase histochemistry revealed 70-100 ganglia of varying sizes. Neurons retrogradely labeled from the rectum were mainly found in ganglia located in the dorso-caudal part of the plexus. The majority of these were non-catecholaminergic, immunoreactive for either calbindin (Calb) or neuropeptide Y (NPY), and characteristically associated with baskets of enkephalin (ENK)-immunoreactive varicose fibers. Neurons projecting to the utero-vaginal walls were distributed in ganglia located in the ventro-caudal part of the plexus. These mainly consisted of two major neuron groups: catecholaminergic Calb-immunoreactive neurons, and non-catecholaminergic neurons containing nitric oxide synthase (NOS) and/or vasoactive intestinal peptide (VIP), which were preferentially associated with a network of ENK-immunoreactive varicose fibers. Neurons retrogradely labeled from the urinary bladder mainly occurred in ganglia located around the junction between the ureter and the bladder. These consisted of catecholaminergic Calb neurons and noncatecholaminergic neurons containing Calb or NOS. Only a few ENK-immunoreactive fibers were found within the clusters of catecholaminergic neurons. These results indicate that organ specific neurons are located in separate ganglia and have both a distinctive composition of neuron types as well as different innervation by preganglionic fibers.  相似文献   
10.
A monoclonal antibody termed "FR77" was obtained from a hybridoma clone established by fusion between P3x63Ag8.653 mouse myeloma cells and spleen cells of a Fischer F344 rat hyperimmune to syngeneic 9L/R3 glioma cells. Immunoperoxidase staining of various cultured cells showed that FR77 was reactive to both rat and human glioma cells, but was not reactive with other nonglioma cells. Immunohistochemical examination of paraffin-embedded or cryostat-frozen sections of various human tissues revealed that FR77 was strongly reactive with glioblastoma, grade III astrocytoma, and craniopharyngioma; partially reactive with intracerebral primitive neuroectodermal tumor, pineoblastoma, and desmoplastic medulloblastoma; and weakly reactive with low-grade astrocytoma. It was not reactive with other types of brain tumors and normal human tissues tested. The FR77-defined antigen was observed to be predominantly localized in the cytoplasm of antigen-bearing cells as suggested by the immunostaining pattern, but part of it was also expressed on the cell surface of glioma cells as demonstrated by a complement-mediated cytotoxic test. Fractionation of the antigenic component and periodic acid treatment of tumor tissue bearing the FR77-defined antigen indicated that the antigen is of a neutral glycolipid nature and that the antigenic determinant to FR77 is present on its sugar portion.  相似文献   
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