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941.
The effects of pepsin on the natural progression of autoimmunity in glomerulonephritis in the NZB/W F1 mouse 总被引:1,自引:0,他引:1
H Ohnishi K Tomita M Kurokawa Y Hayashi H Mochizuki H Inaba H Kosuzume 《Life sciences》1984,35(22):2183-2191
The effects of pepsin on autoimmune glomerulonephritis of New Zealand Black and White F1 hybrid (NZB/W F1) mice were investigated. Intravenous pepsin significantly improved survival rate and suppressed progressive increase in urinary protein and histopathological changes in kidney. Increased serum levels of immune complexes, anti-DNA antibody and natural thymocytotoxic autoantibody were decreased and abnormalities in lymphocyte subsets were ameliorated by pepsin. Pepsin suppressed autoantibody production and enhanced antibody production against xenogeneic substance in these mice. The fact that pepsin ameliorates abnormalities in immune function may contribute to the preventive effects of pepsin against pathogenesis and progression of immune complex nephritis. 相似文献
942.
V Price D Mochizuki C J March D Cosman M C Deeley R Klinke W Clevenger S Gillis P Baker D Urdal 《Gene》1987,55(2-3):287-293
Expression and secretion of two lymphokines, murine granulocyte-macrophage colony-stimulating factor (MuGM-CSF) and bovine interleukin-2 (BoIL-2), to levels of 50-60 mg per liter were achieved by placing these cDNAs in a Saccharomyces cerevisiae expression vector that utilized the yeast alcohol dehydrogenase-2 promoter and alpha-factor leader peptide. These lymphokines were purified to homogeneity by direct application of the crude yeast medium to reversed-phase high-performance liquid chromatography. Despite the fact that both lymphokines contain at least one N-glycosylation site and have identical N-terminal residues (Ala-Pro-Thr), recombinant (R) GM-CSF was found to be heterogeneously glycosylated by yeast while RBoIL-2 was secreted without glycosylation. Additionally, approximately 40% of the RGM-CSF was found to be proteolytically cleaved after the second amino acid residue, while RBoIL-2 was found to be intact. 相似文献
943.
944.
Naoki Hijii 《Ecological Research》1987,2(2):159-173
Seasonal changes in abundance and distribution pattern of soil micro-arthropods were studied in connection with a few environmental
factors in a Japanese cedar (Cryptomeria japonica
D. Don) plantation. The soil arthropods were sampled from three different depths at intervals of two months for two years. Of the
collected animals (total 51000–155000 m−2), Collembola (20000–76000 m−2), oribatid mites (19000–55000 m−2) and carnivorous mites (6200–21000 m−2) were the numerically dominant animal groups. Low seasonal variations in abundance indicated their seasonal stability in
population levels. The trends in seasonal fluctuation were similar among these groups and between the two years, showing bimodal
pattern with little peaks in early summer and winter. The pattern of seasonal fluctuation in abundance of carnivorous mites
(P
d) was significantly synchronized with that in the total abundance of Collembola and oribatid mites (P
τ). Thus, the number-ratios (P
d/P
τ) were fairly constant, ranging from 0.10 to 0.25. Seasonal changes in vertical distribution of the three animal groups showed
a similar pattern for both years. The downward migrations were shown to be more affected by low temperatures in winter accompanied
by snow coverage rather than by the desiccation of the surface soil in summer. All the three groups demonstrated as a whole
slightly aggregated patterns of horizontal distribution throughout the two years. Temporal increases in the patchiness indices
were observed from summer to autumn when the moisture content of the surface soil was low. 相似文献
945.
Naranjan S. Dhalla Vincenzo Panagia Naoki Makino Robert E. Beamish 《Molecular and cellular biochemistry》1988,82(1-2):75-79
In order to identify defects in Na+-Ca2+ exchange and Ca2+-pump systems in cardiomyopathic hearts, the activities of sarcolemmal Na+-dependent Ca2+ uptake, Na+-induced Ca2+ release, ATP-dependent Ca2+ uptake and Ca2+-stimulated ATPase were examined by employing cardiomyopathic hamsters (UM-X7.1) and catecholamine-induced cardiomyopathy produced by injecting isoproterenol into rats. The rates of Na+-dependent Ca2+ uptake, ATP-dependent Ca2+ uptake and Ca2+-stimulated ATPase activities of sarcolemmal vesicles from genetically-linked cardiomyopathic as well as catecholamine-induced cardiomyopathic hearts were decreased without any changes in Na+-induced Ca2+-release. Similar results were obtained in Ca2+-paradox when isolated rat hearts were perfused for 5 min with a medium containing 1.25 mM Ca2+ following a 5 min perfusion with Ca2+-free medium. Although a 2 min reperfusion of the Ca2+-free perfused hearts depressed sarcolemmal Ca2+-pump activities without any changes in Na+-induced Ca2+-release, Na+-dependent Ca2+ uptake was increased. These results indicate that alterations in the sarcolemmal Ca2+-efflux mechanisms may play an important role in cardiomyopathies associated with the development of intracellular Ca2+ overload. 相似文献
946.
Polygonal networks, "geodomes", in cultured hepatocytes of adult rats were examined by both light and electron microscopy. On light microscopical examinations of specimens stained with Coomassie blue after the treatment with Triton X-100, the networks were detected 5 days after culture, which consisted of triangles arranged mainly in hexagonal patterns. They surrounded main cell body, looking like a headband, or were occasionally situated over nuclei, looking like a geodesic dome. Scanning electron microscopical observations after Triton treatment revealed that these structures were located underneath surface membrane. Transmission electron microscopical investigations revealed that the connecting fibers of networks consisted of microfilaments which radiated in a compact bundle from electron-dense vertices. 相似文献
947.
Yoshihito Yawata Kosuke Miyashima Takashi Sugihara Naoki Murayama Saichi Hosoda Shigeru Nakashima Hisaya Iida Yoshinori Nozawa 《生物化学与生物物理学报:生物膜》1984,769(2):440-448
In a patient with lecithin: cholesterol acyltransferase deficiency, free cholesterol was markedly increased, and esterified cholesterol was diminished. In the patient's plasma, an increase in phosphatidylcholine (PC) and a decrease in sphingomyelin were observed. Concomitantly, an increase in a shorter acyl chain 16:0 was noted in PC, sphingomyelin and phosphatidylethanolamine (PE). In contrast to these results, longer chains such as 22:0 and 24:0 were decreased, especially in sphingomyelin. Unsaturated double bonds such as 18:1 was also increased in PC and PE. In the red-cell membrane lipids, the increase in free cholesterol was counteracted by an increase in PC and by a decrease in sphingomyelin and PE, reflecting changes in the patient's plasma lipids. Increased 16:0 (in PC) and decreased 18:0 and 24:0 were observed. The increased plasma free cholesterol due to metabolic defect (lecithin:cholesterol acyltransferase deficiency) led to decreased red-cell membrane fluidity. This effect appeared to be counteracted by changing phospholipid composition (increased PC and decreased sphingomyelin and PE), by increasing shorter chains (16:0), by decreasing longer chains (18:0 and 24:0) and by increasing unsaturated double bonds (18:2). These results can be interpreted as a self-adaptive modification of lecithin:cholesterol acyltransferase deficiency-induced red-cell membrane abnormalities, to maintain normal membrane fluidity. This speculation was supported by the ESR spin-label studies on the patient's membrane lipids. The normal order parameters in intact red cells and in total lipid liposomes were decreased if cholesterol-depleted membrane liposomes were prepared. Thus, the hardening effect of cholesterol appeared to be counteracted by the softening effects described above. Overall membrane fluidity in intact red cells of the lecithin:cholesterol acyltransferase-deficient patient was maintained normally, judged by order parameters in ESR spin-label studies. 相似文献
948.
M Yamamoto K Arishima Y Eguchi K Mochizuki 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1984,176(4):403-406
Pregnant rats were treated with 30 mg metopirone (M) each day for 2 days and autopsied on the third day in various gestational periods (Days 18-20, 19-21, and 20-22). Control rats were treated with saline alone (S). The adrenals of intact fetuses in M-treated dams were significantly heavier than those of intact fetuses in S-treated dams in every experimental period. In both M- and S-treated dams, the adrenals of encephalectomized (E) fetuses were lighter than those of intact littermates. However, in the experimental period of Days 18-20 and 19-21, the adrenals of E fetuses in M-treated dams were slightly but significantly heavier than those of similar E fetuses in S-treated dams. In contrast, in the experimental period Days 20-22, there was no significant difference in the weight of adrenals of E fetuses of M- and S-treated dams. These changes in fetal adrenal weight were reflected histologically in parallel changes in the size of adrenocortical cells. The observations suggest that the fetal adrenal hypertrophy following maternal treatment with metopirone can occur to some extent independent of the fetal brain, but that close to the end of gestation the hypertrophy occurs completely under the control of the fetal brain. 相似文献
949.
950.
Matsuki Rikyu; Iwasaki Toshisuke; Shoji Kazuhiro; Jiang Chang-Jie; Yamamoto Naoki 《Plant & cell physiology》1998,39(8):879-884
The nuclear transport of proteins is mediated by the complexof importin-a and importing. We isolated two cDNAs encodingimporting-rß from rice. A rice importin-rßwas demonstrated to interact with rice GST-importin-a fusionproteins. The presence of two importin-rß genes wasshown for the first time among a variety of eukaryotes. (Received March 30, 1998; Accepted May 13, 1998) 相似文献