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91.
Chromosome aberration frequency in peripheral blood lymphocytes is elevated in radiation-exposed people, and identical karyotypic changes are not infrequently encountered in one blood sample as well as in separate samples from the same donor. Such clonal propagation originates either from a single immature stem cell able to expand and differentiate into several cell types or from a single mature lymphocyte able to expand after antigen stimulation in vivo. In the present study, a total 71 T-lymphocyte and 58 B-lymphocyte colonies were established from one atomic-bomb survivor, who showed a persistent clonal aberration t(4;6), t(5;13) in phytohemagglutinin culture of peripheral lymphocytes. Nearly 10% of the colonies (6 T-lymphocyte and 7 B-lymphocyte colonies) showed the same chromosome abnormality. Southern blot analyses of the T-cell-receptor or Ig heavy-chain gene showed all different rearrangement patterns among T- or B-lymphocyte colonies, respectively. Thus, the chromosome aberration occurred in a precursor cell before differentiation into T and B lineages and was not derived from monoclonal proliferation of mature T or B lymphocytes in the periphery. To confirm the issue, cells from erythroid burst-forming unit (BFU-E) colonies were examined by the chromosome-painting method. Two translocations, one between chromosomes 5 and 13 and the other between chromosomes 4 and one of group C, perfectly consistent with the t(4;6), t(5;13), were found in about 10% of the cells. The results imply that a single stem cell of an adult is capable of generating long- lived myeloid and lymphoid progeny amounting to several percent of the total population of circulating lymphocytes and hematopoietic progenitors. 相似文献
92.
Hiroaki Hoshi Yasuhiro Yuki Shoji Kawano Seishi Jinnouchi Shigeki Nagamachi Takashi Ohnishi Shigemi Futami Katsushi Watanabe Takao Yano 《Annals of nuclear medicine》1990,4(3):83-88
Cerebral blood flow imaging with N-isopropyl (I-123) p-iodoamphetamine (IMP) was performed in 44 patients with ischemic cerebrovascular disease (CVD) at an acute or subacute stage less than 30 days from the onset. IMP imaging was obtained at 20 minutes (early scan) and 4 hours (delayed scan) after intravenous injection of 222 MBq of IMP. The region of interest (ROI) was selected in a slice compatible with the findings on the CT images, and the lesion to tissue ratio (L/T ratio) was calculated in a comparison with the unaffected side. The redistribution index (RI) was also calculated by dividing the difference between the L/T ratio in early and delayed image by the L/T ratio in the early image. The patients were classified into three groups (Grade 1, 2, 3) on the basis of the CT findings. The L/T ratio in the delayed images and RI was high in grade 1 and 2 groups and low in grade 3 groups both in early and delayed scans. The RI had tendency to grow high as the days after the onset became later. In the duration period from 4 to 7 days, 'reversed' redistribution was observed in 4 cases. Follow up examinations were performed in 6 cases in grade 3 group. The RI became higher in 3 cases and lower in 3 cases in the second examination. In conclusion, good redistribution was observed in grade 1 and 2 groups, and the prognosis was good. On the other hand, poor redistribution was observed in grade 3 group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
93.
We have determined bone mineral density (BMD) in hemodialysis patients with various parathyroid function in an attempt to
elucidate the pathology of bone abnormalities, and obtained the following results. It is desirable that BMD (DXA) in the dialysis
patients is determined at the radius rather than at the lumber spine. A higher BMD value might be obtained because of osteosclerosis
of the vertebra or abdominal vascular calcification. The correlation between the SPA and the DXA was favorable in determining
BMD at the distal one-third of the radius. The correlation between Jensen's classification based on subperiosteal resorption,
intact-PTH, and BMD(radius) was favorable. The annual decrease in BMD was 4.0% and 4.7% in the male patients within 8 years
and the female within 6 years after starting dialysis, respectively, and thier BMD decreased to 70 at above mentioned year.
The annual BMD decrease became larger in the patients with severe 2'HPT, i.e., 7.1% in the male patients and 10.0% in the
female patients. BMD after PTX markedly increased in the patients showing BMD of less than 70 at PTX. The BMD in one male
patient who showed aluminium induced osteomalacia in past history was maintained at a relatively favorable value. The biochemical
examination of two female patients who became an aparathyroid state after PTX showed improved values, but their BMD gradually
decreased without showing any increase. 相似文献
94.
Aramaki Yukihiko Arima Hidetoshi Hara Toshifumi Tsuchiya Seishi 《Pharmaceutical research》1996,13(9):1389-1392
Purpose. The effects of liposomes on nitric oxide (NO) production from mouse peritoneal macrophages following intraperitoneal injection of liposomes were investigated.
Methods. Mouse peritoneal macrophages were collected following intraperitoneal injection of liposomes and cultured with and without lipopolysaccharide (LPS). Peritoneal washing fluid was also collected from the mice injected with liposomes. NO production was evaluated by measuring the concentration of nitrite in the macrophage culture supernatant by Griess reagent.
Results. NO production stimulated by LPS was observed in peritoneal macrophages obtained from the liposome-treated mice, but liposomes did not activate macrophages directly to induce NO in response to LPS. NO production was higher in the liposomes composed of phospha-tidylcholine than that of negatively charged liposomes composed of phosphatidylserine. Peritoneal washing fluid obtained from mice injected with liposomes has a capacity to induce NO production in the macrophages from naive mice. This capacity was not diminished by heat-treatment at 100°C for 5 min.
Conclusions. Peritoneal macrophages were activated to produce NO in response to LPS following intraperitoneal injection of liposomes. They did not activate macrophages directly, and the induction of heat-stable macrophage priming factor, but not cytokines, is suggested. 相似文献
95.
Leo G. Flores Shigeki Nagamachi Ryuichi Nishii Seishi Jinnouchi Takashi Ohnishi Yoshio Shimao Katsushi Watanabe Shozo Tamura 《Annals of nuclear medicine》1998,12(2):105-108
The case of a 77-year-old male patient who complained of left upper quadrant pain and progressive vomiting. Laboratory examination showed extremely high lactic acid dehydrogenase (LDH) and adult T-cell leukemia antibody (ATLA). The anatomical studies CT, MRI, US and upper GI series substantiated an omental lymphadenopathy which was causing a circumferential compression of portions of the duodenum and jejunum. Gallium-67 citrate (Ga-67) scintigraphy showed high uptake at LUQ. Ultrasound guided biopsy failed to confirm the diagnosis. Irradiation was performed. Ga-67 scintigraphy had a contributory role in clinical subtyping of the disease, planning of treatment, posttreatment assessment and prognostication of adult T-cell lymphoma. 相似文献
96.
97.
Yoshiro Niitsu Yoshikazu Koshida Katsuo Mahara Seishi Ishigaki Katsuhisa Kogawa Naoki Watanabe Yoichi Urushizaki Yutaka Kongo Ichiro Urushizaki 《Immunopharmacology and immunotoxicology》1988,10(1):67-78
The response of a highly metastatic cell line of methylcholanthrene induced A fibrosarcoma (Meth A) to growth factors from platelets was examined. The highly metastatic cell subline (MH) proliferated more rapidly than its parental counterpart cell subline (ML) in a medium containing platelet lysate. However, when the three major growth factors from platelets, ie, platelet-derived growth factor, epidermal growth factor, and transforming growth factor-β(PDGF, EGF, TGF-β), were independently examined for their growth promoting activity, the former 2 growth factors preferentially stimulated the proliferation of ML and the latter growth factor rather suppressed the growth of both cells.
On the other hand, the combined effects of these factors were more marked on MH. This combination effect was supported by the evidence that the number of receptors for EGF (which is probably an essential growth factor for the Meth A cell) was increased by pretreatmenl with PDGF or TGF-β. Thus, the highly metastatic cells of MH were considered to be the most susceptible to growth factors released from platelets. This conclusion is consistent with the concept that platelets may play an important role in the formation of blood-borne metastasis by releasing growth factors to promote the proliferation of tumor cells, following aggregation with tumor cells. 相似文献
On the other hand, the combined effects of these factors were more marked on MH. This combination effect was supported by the evidence that the number of receptors for EGF (which is probably an essential growth factor for the Meth A cell) was increased by pretreatmenl with PDGF or TGF-β. Thus, the highly metastatic cells of MH were considered to be the most susceptible to growth factors released from platelets. This conclusion is consistent with the concept that platelets may play an important role in the formation of blood-borne metastasis by releasing growth factors to promote the proliferation of tumor cells, following aggregation with tumor cells. 相似文献
98.
Haraguchi K Takahashi T Nakahara F Matsumoto A Kurokawa M Ogawa S Oda H Hirai H Chiba S 《Leukemia & lymphoma》2006,47(10):2218-2223
Invariant natural killer T (iNKT) cells are thought to regulate anti-tumor immunity. Human iNKT (i.e. Valpha24+ NKT) cells have been reported to recognize CD1d on target cells and show cytotoxicity directly on the target cells in vitro. However, the anti-tumor effect of mouse iNKT (i.e. Valpha14+ NKT) cells has been repeatedly reported to be dependent on the activity of natural killer (NK) cells via interferon-gamma, with no evidence of direct cytotoxicity. In the present study, we report that in vitro cytolysis of EL-4 mouse lymphoblastic lymphoma cells by Valpha24+ NKT cells and in vivo eradication of these cells are both dependent on the level of CD1d expression on the tumor cell surface. These observations possibly suggest that direct cytotoxicity of tumor cells by iNKT cells is common to both humans and mice, and that the high expression level of CD1d may be a predictor whether the tumor is a good target of iNKT cells. 相似文献
99.
Comparison of inhibitory effects of polyanions on nitric oxide production by macrophages stimulated with LPS 总被引:3,自引:0,他引:3
In this paper, we investigated the inhibitory mechanism of the production of nitric oxide (NO) by polyanions and liposomes composed of phosphatidylserine (PS-liposomes) focusing on cytokine production and mitogen activated protein kinase (MAP kinase) activation. NO production by macrophages was inhibited by treatment with oxidized lipoprotein (OxLDL), maleylated bovine serum albumin (mBSA), and heparin. No inhibitory effect was exhibited by poly-cytidilic acid (PolyC). To clarify the mechanism of the inhibitory effect of polyanions on NO production, we evaluated the productions of transforming growth factor-beta (TGF-beta) and interleukin (IL)-10 which are known to be anti-inflammatory cytokines. TGF-beta was produced when macrophages were treated with OxLDL as was the case with PS-liposomes. No increase in TGF-beta production was observed for mBSA, heparin, and PolyC. On the other hand, significant production of IL-10 was observed using mBSA. Extracellular signal-regulated kinase (ERK), a member of the MAP kinase superfamily, was activated when macrophages were treated with OxLDL as well as PS-liposomes. In the case of mBSA, the activation of ERK and c-Jun N-terminal kinase (JNK) was observed. No activation of p38 MAP kinase was observed using any of the polyanions. Although heparin had an inhibitory effect on NO production by macrophages, no activation of MAP kinase or production of TGF-beta and IL-10 was observed. The inhibitory effect of these ligands on NO production may be regulated via different signaling pathways. 相似文献
100.
Changes in immune responses to mite antigen sensitized through barrier-disrupted skin with CpG-oligodeoxynucleotide in mice 总被引:1,自引:0,他引:1
Inoue J Yotsumoto S Sakamoto T Tsuchiya S Aramaki Y 《Biological & pharmaceutical bulletin》2006,29(2):385-387
CpG-oligodeoxynucleotide (CpG-ODN) plays a critical role in immunity via the augmentation of Th1 and suppression of Th2 responses. We examined here the effect of CpG-ODN on the immune response to mite antigen sensitized through barrier-disrupted skin of human atopic dermatitis (AD) model mouse. Although sensitization with mite antigen induced Th2-dominant immune response, co-administration of CpG-ODN elicited Th1-predominant immune response. In terms of antigen-specific antibody production, the level of IgG2a was increased by CpG-ODN, but not in IgE. These results suggested that administration of CpG-ODN via skin is a simple strategy for patients with diseases like AD, which is characterized by Th2-dominated inflammation. 相似文献