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1.
The nucleotide sequence of a cloned cDNA corresponding to the P+M dicistronic mRNA of a subacute sclerosing panencephalitis (SSPE) virus was determined and compared with data of measles virus (MV). The dicistronic mRNA of the SSPE virus consisted of the 3 proximal 626 nucleotides of P mRNA, intercistronic trinucleotides, a full length of M mRNA, and 75 poly A nucleotides. The part encoding the P protein had a high homology to MV, except at the noncoding region. The terminating consensus sequence of the P gene and the intercistronic trinucleotides of the SSPE virus were CTAC(A)6 and CCT; in MV they are TTAT(A)6 and CTT, respectively. In the M gene, the starting consensus sequence was exactly the same as MV, but at the 5 proximal end, one third of this gene was different: The first ATG codon of the MV M gene signaling opening of the reading frame was changed to ACG in the SSPE virus and one long open reading frame started from the third ATG codon. The stop codon (TAG) of the MV M gene was also changed to CAG in the SSPE virus. Thus, the deduced SSPE-virus M protein lacked 50 amino acids at the amino terminal and had 15 extra amino acids at the carboxyl end when compared with the MV M protein.  相似文献   
2.
The multiple tumor suppressor 1 (MTS1) gene is homozygously deleted frequently in cell lines derived from a wide variety of tumors. We investigated the deletion of the MTS1 gene in esophageal cancer cell lines and primary esophageal squamous carcinomas using the polymerase chain reaction. Sixteen and 15 of 23 esophageal cancer cell lines showed homozygous deletion of MTS1 exon 1 and exon 2, respectively, while none of 21 primary esophageal carcinomas showed the deletion. An analysis of MTS1 gene mutations was carried out by direct DNA sequencing in 8 cell lines and 21 primary carcinomas showing no homozygous deletion. In contrast to previous reports of esophageal carcinoma, there were no mutations recognized in the region sequenced. Our study suggests that the inactivation of the MTS 1 gene may play an important role in esophageal carcinoma cell lines but may be less important in primary carcinomas of the human esophagus.  相似文献   
3.
Primary anaplastic large cell lymphoma (ALCL) of skeletal muscle is very rare. We report a case of ALCL arising from the left psoas muscle. A 14-year-old girl presented with a large left inguinal tumor. She complained of a 2-month history of left leg pain, which had been exacerbated upon leg extension, and she had become aware of a rapidly growing left inguinal tumor 3 weeks before admission. CT scan and MRI revealed a large tumor arising from the left major psoas muscle and protruding into the inguinal region. In view of the tumor's location and the patient's age, soft tissue tumors such as rhabdomyosarcoma and primitive neuroectodermal tumor were initially considered. However, histopathological examination yielded a diagnosis of anaplastic lymphoma kinase-positive ALCL. The serum level of soluble interleukin-2 receptor was markedly elevated at 50,414 U/ml, and this also strongly suggested ALCL. Although rarely reported, ALCL is an important entity to consider in the differential diagnosis of skeletal muscle tumors in children and young adults.  相似文献   
4.
VacA was histochemically stained in biopsy specimen and was intracellularly and mainly located in fundic gland area. It is recognized gastric atrophy was observed in the H. pylori-positive patients with intracellular VacA compared with others. The aim of study is to understand the relationship between intracellular VacA and the progression of gastric atrophy that is associated with gastric cancer. Biopsy specimens and sera were obtained from 364 people in their 50s and 60s without gastric cancer diagnosed at first endoscopy undergoing diagnostic endoscopy, for H. pylori infection, histology, and the histochemical status of intracellular VacA using anti-VacA Ab during the follow-up period (mean, 7.3 years). Three hundred eleven of 364 enrolled patients were H. pylori positive and 53 patients were H. pylori negative at first endoscopy. VacA was intracellularly stained with vacuolation and cell destruction in the fundic gland in 98 of 311 H. pylori-positive patients and not stained in another 213 H. pylori-positive patients plus 53 H. pylori-negative patients at first endoscopy. Gastric atrophy has significantly progressed in the H. pylori-positive patints with intracellular VacA with gastric ulcers compared with the others and six gastric cancers have developed in this group during the follow-up period (mean, 7.3 years). Intracellular VacA is a valuable marker to predict whether Helicobacter pylori induces progressive atrophic gastritis that is associated with the development of gastric cancer.  相似文献   
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Basaloid-Squamous Carcinoma of the Esophagus: Report of a Case   总被引:2,自引:0,他引:2  
(Received for publication on Oct. 27, 1998; accepted on July 13, 1999)  相似文献   
8.
Differential cDNA displays between hepatocellular carcinoma and adjacent non-malignant tissues have previously detected a PCR product, hIRH (human intercrine reduced in hepatomas), equivalent to SDF1alpha/PBSF whose mRNA was lost from human hepatocellular carcinoma and other malignant and pre-malignant samples and malignant cell lines. There are no reports to date of the mRNA status of the receptor for hIRH/SDF1alpha/PBSF, CXCR4 in malignant tissues. We report here that there is a reduction in the mRNA expression of CXCR4 in hepatocellular carcinoma as estimated by Northern blot and RT-PCR and compared to the adjacent non-malignant tissue. The average (mean SD) tumor/normal ratio for CXCR4 mRNA expression, determined by RT-PCR, was 0.65 0.36 in 10 pairs of hepatocellular carcinomas. There was no consistent loss of CXCR4 mRNA expression in a range of malignant cell lines. The 3'-non-coding region of hIRH, had typical early response gene element sequences. Despite the presence of these 3'-elements there was no induction of hIRH gene expression in human lung carcinoma A549 cells by tumor necrosis factor alpha, interleukin-2, lipopolysaccharide or phorbol myristic acetate, nor in human melanoma cell line SB-2 by uv irradiation, under conditions which induced the homologue CXC intercrine IL-8 expression. Furthermore, there was no induction of hIRH gene expression, but rather a suppression, upon serum or cytokine addition to serum-deprived fibroblast cell lines, to an in vitro mouse bone marrow preparation, and to monocytic cell line THP-1.  相似文献   
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S100B, a 21-kD Ca2+ binding protein expressed in Schwann cells and astroglia, has often been reported as a promising biomarker for ischemic stroke. In addition to ischemic stroke, the peripheral S100B level may also be useful as a biomarker for intracerebral hemorrhage (ICH). However, the kinetics and characterization of peripheral S100B in patients or experimental animal models with ICH have not been carefully examined. The present study investigated the kinetics and characteristics of the serum S100B level in a rat collagenase-induced ICH model. The serum S100B kinetics and the time-course of brain edema and hematoma formation were examined. Then, the correlations between the elevated serum S100B level and brain edema or hematoma formation were investigated. A transient elevation of serum S100B that peaked at 6 h after ICH induction was observed. The single measurement of serum S100B at 6 h after ICH induction was significantly correlated with brain edema formation and the maximal extent of the hematoma volumes. These results suggest the significance of serum S100B as a biomarker of brain damage resulting from ICH.  相似文献   
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