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71.
Effects of dietary soybean peptides on hepatic production of ketone bodies and secretion of triglyceride by perfused rat liver 总被引:2,自引:0,他引:2
Tamaru S Kurayama T Sakono M Fukuda N Nakamori T Furuta H Tanaka K Sugano M 《Bioscience, biotechnology, and biochemistry》2007,71(10):2451-2457
Soybean protein isolate (SPI) was digested with protease to produce a peptides containing the low-molecular fraction (LD3) or a mixture of high- and low-molecular fractions (HD1). Rats were fed a diets containing SPI, LD3, or HD1 at a protein level equivalent to the 20% casein diet for 4 weeks. The serum triglyceride concentration was lower in rats fed SPI, LD3, and HD1 diets than in rats fed the casein diet, and the differences were significant for the cholesterol-enriched diet. The value for the LD3 group was the lowest among all groups for both the cholesterol-free and -enriched diets. The level of triglyceride in the post-perfused liver was significantly lower in the LD3 and HD1 groups and the SPI group than in the casein group irrespective of the presence of cholesterol in the diet. In the cholesterol-free diet, LD3 feeding as compared to casein feeding caused a reduction in triglyceride secretion from the liver to perfusate and an increment of hepatic ketone body production. The addition of cholesterol to the diets somewhat attenuated these effects of LD3. These results suggest that the low-molecular fraction in soybean peptides causes triglyceride-lowering activity through a reduction in triglyceride secretion from the liver to the blood circulation and the stimulation of fatty acid oxidation in the liver. There is a possibility that soybean peptides modulate triglyceride metabolism by changes in the hepatic contribution. 相似文献
72.
Okada E Yamazaki M Tanabe M Takeuchi T Nanno M Oshima S Okamoto R Tsuchiya K Nakamura T Kanai T Hibi T Watanabe M 《American journal of physiology. Gastrointestinal and liver physiology》2005,288(4):G745-G754
We have previously demonstrated that mucosal CD4(+) T cells expressing high levels of IL-7 receptor (IL-7R(high)) are pathogenic cells responsible for chronic colitis. Here we investigate whether IL-7 is directly involved in the expansion of IL-7R(high) memory CD4(+) mucosal T cells and the exacerbation of colitis. We first showed that CD4(+) lamina propria lymphocytes (LPLs) from wild-type, T cell receptor-alpha-deficient (TCR-alpha(-/-)), and recombinase-activating gene (RAG)-2(-/-)-transferred mice with or without colitis showed phenotypes of memory cells, but only CD4(+) LPLs from colitic mice showed IL-7R(high). In vitro stimulation by IL-7, but not by IL-15 and thymic stromal lymphopoietin, enhanced significant proliferative responses and survival of colitic CD4(+), but not normal CD4(+) LPLs. Importantly, in vivo administration of IL-7 mice accelerated the expansion of IL-7R(high) memory CD4(+) LPLs and thereby exacerbated chronic colitis in RAG-2(-/-) mice transferred with CD4(+) LPLs from colitic TCR-alpha(-/-) mice. Conversely, the administration of anti-IL-7R monoclonal antibody significantly inhibited the development of TCR-alpha(-/-) colitis with decreased expansion of CD4(+) LPLs. Collectively, the present data indicate that IL-7 is essential for the expansion of pathogenic memory CD4(+) T cells under pathological conditions. Therefore, therapeutic approaches targeting the IL-7R pathway may be feasible in the treatment of human inflammatory bowel disease. 相似文献
73.
Spermatogenesis consists of complex cellular and developmental processes, such as the mitotic proliferation of spermatogonial stem cells, meiotic division of spermatocytes, and morphogenesis of haploid spermatids. In this study, we show that RNA interference (RNAi) functions throughout spermatogenesis in mice. We first carried out in vivo DNA electroporation of the testis during the first wave of spermatogenesis to enable foreign gene expression in spermatogenic cells at different stages of differentiation. Using prepubertal testes at different ages and differentiation stage-specific promoters, reporter gene expression was predominantly observed in spermatogonia, spermatocytes, and round spermatids. This method was next applied to introduce DNA vectors that express small hairpin RNAs, and the sequence-specific reduction in the reporter gene products was confirmed at each stage of spermatogenesis. RNAi against endogenous Dmc1, which encodes a DNA recombinase that is expressed and functionally required in spermatocytes, led to the same phenotypes observed in null mutant mice. Thus, RNAi is effective in male germ cells during mitosis and meiosis as well as in haploid cells. This experimental system provides a novel tool for the rapid, first-pass assessment of the physiological functions of spermatogenic genes in vivo. 相似文献
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Tsubaki M Kato C Manno M Ogaki M Satou T Itoh T Kusunoki T Tanimori Y Fujiwara K Matsuoka H Nishida S 《Molecular and cellular biochemistry》2007,304(1-2):53-60
Osteolytic lesions are rapidly progressive during the terminal stages of myeloma, and the bone pain or bone fracture that
occurs at these lesions decreases the patients’ quality of life to a notable degree. In relation to the etiology of this bone
destruction, it has been reported recently that MIP-1α, produced in large amounts in myeloma patients, acts indirectly on
osteoclastic precursor cells, and activates osteoclasts by way of bone-marrow stromal cells or osteoblasts, although the details
of this process remain obscure. In the present study, our group investigated the mechanism by which RANKL expression is induced
by MIP-1α and the effects of MIP-1α on the activation of osteoclasts. RANKL mRNA and RANKL protein expressions increased in
both ST2 cells and MC3T3–E1 cells in a MIP-1α concentration-dependent manner. RANKL mRNA expression began to increase at 1 h
after the addition of MIP-1α; the increase became remarkable at 2 h, and continuous expression was observed subsequently.
Both ST2 and MC3T3-E1 cells showed similar levels of increased RANKL protein expression at 1, 2, and 3 days after the addition
of MIP-1α. After the addition of MIP-1α, the amount of phosphorylated ERK1/2 and Akt protein expressions showed an increase,
as compared to the corresponding amount in the control group. On the other hand, the amount of phosphorylated p38MAPK protein
expression showed a decrease from the amount in the control group after the addition of MIP-1α. U0126 (a MEK1/2 inhibitor)
or LY294002 (a PI3K inhibitor) was added to ST2 and MC3T3-E1 cells, and was found to inhibit RANKL mRNA and RANKL protein
expression in these cells. When SB203580, a p38MAPK inhibitor, was added, RANKL mRNA and RANKL protein expression were increased
in these cells. MIP-1α was found to promote osteoclastic differentiation of C7 cells, an osteoclastic precursor cell line,
in a MIP-1α concentration-dependent manner. MIP-1α promoted differentiation into osteoclasts more extensively in C7 cells
incubated together with ST2 and MC3T3-E1 cells than in C7 cells incubated alone. These results suggested that MIP-1α directly
acts on the osteoclastic precursor cells and induces osteoclastic differentiation. This substance also indirectly induces
osteoclastic differentiation through the promotion of RANKL expression in bone-marrow stromal cells and osteoblasts. The findings
of this investigation suggested that activation of the MEK/ERK and the PI3K/Akt pathways and inhibition of p38MAPK pathway
were involved in RANKL expression induced by MIP-1α in bone-marrow stromal cells and osteoblasts. This finding may be useful
in the development of an osteoclastic inhibitor that targets intracellular signaling factors. 相似文献
78.
Sumino H Takahashi M Yamaguchi T Abe K Araki N Yamazaki S Shimozaki S Nagano A Nishio N 《Bioresource technology》2007,98(1):177-182
A feasibility test of a 17 m3-pilot-scale sewage treatment system was carried out by continuous feeding of raw municipal sewage under ambient temperature conditions. The system consisted of a UASB and an aerated fixed bed reactor. Some of the effluent from the fixed bed reactor was returned to the UASB influent in order to provide a sulfate source. The total BOD of 148-162 mg l(-1) in the influent was reduced to a more desirable 11-25 mg l(-1) in the final effluent. The levels of methane-producing activity from acetate and H2/CO2 gas at 10 degrees C were only 2% and 0% of those at 35 degrees C, respectively. On the other hand, the sulfate-reducing activity levels of the UASB sludge were relatively high at 10 degrees C, for example, 18% for acetate and 9% for H2/CO2 gas, compared to the activity levels at 35 degrees C. Therefore, BOD oxidization by sulfate reduction in the UASB was greater than that by methane production under low temperature conditions. This sulfate-reducing activity tended to be proportional to the copy number of adenosine-5'-phosphosulfate (APS) reductase genes in DNA extracted from the sludge. 相似文献
79.
Miyazawa Atsuhiro Kanahara Nobuhisa Kogure Masanobu Otsuka Ikuo Okazaki Satoshi Watanabe Yoshinori Yamasaki Fumiaki Nakata Yusuke Oda Yasunori Hishimoto Akitoyo Iyo Masaomi 《Molecular biology reports》2022,49(3):2015-2024
Molecular Biology Reports - GABAergic system dysfunction has been implicated in the etiology of schizophrenia and of cognitive impairments in particular. Patients with treatment-resistant... 相似文献
80.
Antimalarial activity of endoperoxide compound 6-(1,2,6,7-tetraoxaspiro[7.11]nonadec-4-yl)hexan-1-ol
Sato A Hiramoto A Morita M Matsumoto M Komich Y Nakase Y Tanigawa N Hiraoka O Hiramoto K Hayatsu H Higaki K Kawai S Masuyama A Nojima M Wataya Y Kim HS 《Parasitology international》2011,60(3):270-273
Plasmodium falciparum, the major causative parasite for the disease, has acquired resistance to most of the antimalarial drugs used today, presenting an immediate need for new antimalarial drugs. Here, we report the in vitro and in vivo antimalarial activities of 6-(1,2,6,7-tetraoxaspiro[7.11]nonadec-4-yl)hexan-1-ol (N-251) against P. falciparum and Plasmodium berghei parasites. The N-251 showed high antimalarial potencies both in the in vitro and the in vivo tests (EC50 2.3 × 10−8 M; ED50 15 mg/kg (per oral)). The potencies were similar to that of artemisinin in vitro and greater than artemisinin's activity in vivo (p.o.). In addition, N-251 has little toxicity: a single oral administration at 2000 mg/kg to a rat gave no health problems to it. Administration of N-251 to mice bearing 1% of parasitemia (per oral 68 mg/kg, 3 times a day for 3 consecutive days) resulted in a dramatic decrease in the parasitemia: all the 5 mice given N-251 were cured without any recurrence, with no diarrhea or weight loss occurring in the 60 days of experiment. N-251 deserves more extensive clinical evaluation, desirably including future trials in the human. 相似文献