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141.
Hiroshi Sonobe Jun Iwata Mutsuo Furihata Yuji Ohtsuki Hiroo Mizobuchi Hiroshi Yamamoto 《Pathology international》1994,44(5):407-411
Periosteal osteosarcoma is an exceedingly rare type of chondroblastic osteosarcoma, showing rather better prognosis, and secondary bone marrow involvement is unusual. A case of a 22 year old male with periosteal osteosarcoma of the right femur with an associated bone marrow lesion is presented. The juxtacortical tumor, 16 ×11 × 9 cm, was located on the bone cortex of the upper diaphysis and extended into the surrounding soft tissues. A minimal bone marrow lesion was present, although the bone cortex was quite intact. Microscopically, the tumor consisted exclusively of atypical chondroblastic cells with a small osteoblastic area. The bone marrow lesion, interestingly, contained both multiple nodules of well-differentiated chondrosarcomatous components and a few demarcated foci of atypical spindle cells producing a fine osteoid matrix. It was reasonable to conclude, therefore, that this tumor was a periosteal osteosarcoma with an unusual secondary bone marrow lesion rather than a conventional (central) chondroblastic osteosarcoma with soft tissue invasion. The patients good prognosis with no tumor recurrence or metastasis during more than 7 years follow-up after surgery supports this conclusion. 相似文献
142.
Hidai C Kawana M Habu K Kazama H Kawase Y Iwata T Suzuki H Quertermous T Kokubun S 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,287(2):1165-1175
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery. 相似文献
143.
Muramatsu H Horii T Morita M Hashimoto H Kanno T Maekawa M 《International journal of medical microbiology : IJMM》2003,293(2-3):191-197
We evaluated effects of medium composition, including basic amino acid content and pH, on susceptibility to carbapenems such as imipenem, panipenem and meropenem, in clinical isolates of Pseudomonas aeruginosa. Susceptibility to carbapenems was reduced by basic amino acids in the medium, while susceptibilities to ceftazidime and aztreonam were not. Among carbapenems, susceptibility to panipenem was most sharply reduced by addition of basic amino acids to 1:16 Mueller-Hinton agar (MHA). In 174 of 175 clinical isolates, MICs for carbapenems were affected to different degrees by medium composition. One isolate, in which MICs for carbapenems did not differ between MHA and 1:16 MHA, showed reduced production of porin (OprD). Our results suggest that susceptibility to individual carbapenems, especially panipenem, is difficult to evaluate based on MICs for other carbapenems determined on MHA. For a better prediction of antibiotic efficacy, it may be important to evaluate the susceptibility for each carbapenem individually. 相似文献
144.
Mashima Y Shinoda K Ishida S Ozawa Y Kudoh J Iwata T Oguchi Y Shimizu N 《Human mutation》1999,13(4):338
The XLRS1 gene (HUGO-approved symbol, RS1) has been found to cause X-linked recessive retinoschisis (RS) which is characterized by splitting of the superficial layer of the retina. Recent mutation analysis of this gene revealed 82 different mutations in 214 patients with RS. We have now identified 10 mutations of the XLRS1 gene in 11 unrelated Japanese males with RS. Mutations found in these patients were; 1) a 20-kb deletion in exon 1 region; 2) mutations in the initiation sequence (M1V); 3) mutations in the splice donor site (IVS1 + 1 g-->a); 4) two nonsense mutations (Q88X, W163X); and 5) five missense mutations (E72K, Y89C, R182C, G109E, P203L). Four (M1V, Q88X, G109E, and W163X) of the 10 mutations were novel. The R182C mutation was identified in 2 unrelated patients. The 3 mutations found between exons 1 and 3 cause premature translation termination in the XLRS1 protein. The rest of the 7 mutations were clustered between exons 4 and 6. This region of the protein is homologous to the proteins implicated in cell-cell adhesion. 相似文献
145.
A case of polypoid carcinosarcoma of the esophagus is presented. Histologically the bulk of the tumor consisted of a sarcomatous tissue having large foci of osseous and cartilagenous differentiation and infiltrating deeply the wall, whereas a superficially, invasive squamous cell carcinoma associated with insitu carcinoma was located at the base and luminal surface of the polypoid tumor. Intermingling of the carcinomatous and sarcomatous elements was found only in areas where they appeared to be collided. Ultrastructurally the sarcomatous portion contained cells with fibroblastic features but with no typical epithelial characteristics. Immunoperoxidase staining of the paraffinembedded histologic sections for keratin proteins revealed, however, some positive spindle cells indicative of epithelial nature in the sarcomatous area, but the great majority of the sarcoma cells were devoid of keratin. These combined findings strongly suggest that the sarcomatous component in our case of true carcinosarcoma is derived from mesenchymal transformation (metaplasia) of the squamous carcinoma cells. The findings were discussed in light of the previous pertinent literature. ACTA PATHOL, JPN. 34: 669–678, 1984. 相似文献
146.
Positive and negative selection events are involved in determining useful T cell clones to mature in the thymus. Accumulating evidence suggests that immature self-reactive thymocytes undergo apoptotic death (negative selection) upon stimulation via the T cell receptors (TcR). A similar phenomenon of activation-induced death has been reported in T cell hybridomas. On the other hand, little is known about the mechanism of the positive selection. Apoptosis in rodent thymocytes or T cell hybridomas is also known to be induced by glucocorticoids in vitro at concentrations within the physiologic range. We report here that the TcR/CD3-mediated stimulation and glucocorticoids mutually inhibit the apoptosis in T cell hybridomas. The production of interleukin 2 by the rescued cells indicated that the TcR/CD3-mediated signal was transduced into the cells. Thymocytes were also rescued from glucocorticoid-induced apoptosis by the stimulation with antibodies to TcR/CD3 molecules. The rescue of thymocytes, however, was observed only at a narrow concentration range of each of the antibodies, suggesting that the proper stimulation via the TcR/CD3 is required for the rescue. If thymocytes in situ are differentially stimulated according to the affinity of the TcR towards self, only the thymocytes whose TcR have proper affinity towards self may be rescued from glucocorticoid-induced apoptosis. Therefore, we propose a hypothesis that the positive selection of the T cell repertoire is based on the inhibition of glucocorticoid-induced apoptosis in immature thymocytes bearing TcR with proper affinity for self by the TcR-mediated signals in situ. Furthermore, the selection may be influenced by the peak level of glucocorticoid concentration, since the proper concentration range of the anti-TcR/CD3 antibody for the rescue was variable depending on the glucocorticoid concentration. 相似文献
147.
Kengo Funakoshi Masato NakanoYoshitoshi Atobe Tetsuo KadotaRichard C. Goris 《Neuroscience letters》2006
The visceral reflexes of the pelvic organs are mediated by connections between primary afferents innervating the pelvic organs and parasympathetic preganglionic neurons in the intermediolateral column of the sacral spinal cord. The present immunohistochemical study revealed many varicosities expressing transient receptor potential vanilloid 1 (TRPV1) that were closely apposed to the preganglionic neuronal perikarya at embryonic day 16 in mice. Many, but not all, varicosities expressing TRPV1 in the intermediolateral column were also immunopositive for calcitonin gene-related peptide. In contrast, no nerve fibers expressing TRPV1 projected to the sympathetic preganglionic cell column in the lumbar spinal cord in prenatal stages. The results of the present study raised the possibility that the primary afferents transmit signals elicited by the activation of TRPV1 receptors to the sacral parasympathetic preganglionic neurons. Thus, the functional circuit for pelvic spinal reflexes, such as micturition induced by urine influx, might develop in the prenatal stages in mice. 相似文献
148.
Kunio Ichijima Hirohiko Yamabe Yoichiro Kobashi Takekuni Iwata 《Pathology international》1980,30(2):293-300
A case of a 41 years old Japanese woman with widely disseminated primary lung cancer (adenocarcinoma) metastasizing to renal cell carcinoma (hypernephroma) is presented together with a brief review of the literature. 相似文献
149.
Kimura M Takahashi T Iwata A Matsumoto N Ogura Y Akagi T Akima S Kobayashi K Moro I 《Scandinavian journal of immunology》2001,54(6):613-618
We used Northern blot analysis in order to investigate the ontogeny of the murine joining (J)-chain gene. No J-chain expression was detected in embryonic tissues, including liver, spleen and intestine, but an expression of mu heavy chain was detected in foetal liver at day 17. J-chain expression was detected in the spleen at day 9 and in the intestine at day 15 after birth. Western blot analysis was carried out in order to compare the protein levels of J and mu heavy chains in serum from day 8 to day 24 after birth, using antihuman J chain and antimouse mu chain antibodies. Although mu chain protein could be detected in serum from day 8, J-chain protein was detectable only at day 24. These results suggest that the expression of J chain is a later event than the mu chain in the mouse, which thus differs in embryogenesis from humans. 相似文献
150.
Shimoyama M Matsuoka H Tamekane A Ito M Iwata N Inoue R Chihara K Furuya A Hanai N Matsui T 《Growth factors (Chur, Switzerland)》2000,18(1):63-78
Although most kinase-defective growth factor receptor proteins are associated with pathogenic conditions, a kinase-defective Eph-family receptor protein, EphB6, is expressed in normal human tissues. We generated monoclonal antibodies specific for human EphB6 to characterize its expression on human hematopoietic cells. A very small population of normal human peripheral white blood cells (0.57 +/- 0.07%, n = 12) expressed EphB6. The EphB6-positive cells were CD2+, CD7+, CD3+ and CD4+ or CD8+ lymphocytes, but they did not express CD19 or CD11b. In human bone marrow, only 1.5 +/- 0.19% of lymphocytes expressed EphB6. Compared with the expression in peripheral lymphocytes, prominent expression of EphB6 protein was demonstrated in CD4+CD8+ double-positive mouse thymocytes. The T-cell lineage-specific expression was strictly conserved in human leukemia/lymphoma cells. Among T-cell-derived leukemia cells, the expression level of EphB6 seemed to decrease with maturation of the cells. These results suggest that EphB6 expression is regulated in T-cell development. 相似文献