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101.
Summary Taurine which has antioxidant effects is also known to have effects on cell proliferation, inflammation and collagenogenesis. The aim of this study was to investigate the effect of taurine on incisional skin wounds.The mice incised on the dorsal area were divided into control and experimental groups. Saline was injected intraperitoneally to half of the animals in the control group and locally applied to the other half. Fifty mM taurine solution was given intraperitoneally to the first half of the experimental animals and locally to the second half of the experimental group.After four days of treatment, malondialdehyde (MDA) and histamine levels as well as the tensile strength of the wound tissue were measured. Structural alterations in epidermis and dermis were histologically evaluated.The locally administreated taurine significantly increased wound tensile strength by decreasing the MDA and histamine levels and prevented the degranulation of the mast cells. These observations suggest that taurine may be useful on wound healing. 相似文献
102.
Kurt W. Schmid Birgit Kunk Rudolf Kirchmair Martin T?tsch Werner B?cker Reiner Fischer-Colbrie 《The Histochemical journal》1995,27(6):473-481
Summary An antiserum raised against a synthetic peptide derived from the primary amino sequence of rat secretogranin II (chromogranin
C) was used for immunological (quantitative radioimmunoassay analysis) and immunohistochemical studies of normal human endocrine
and nervous tissues. This antibody recognized a novel and biologically active neuropeptide which was coined as secretoneurin.
In endocrine tissues, secretoneurin was mainly co-localized with chromogranin A and B with some exceptions (e.g., parathyroid
gland). Secretoneurin was demonstrated immunohistochemically in the adrenal medulla, thyroid C cells, TSH- and FSH/LH-produting
cells of the anterior pituitary, A and B cells of pancreatic islets, in endocrine cells of the gastrointestinal tract and
the bronchial mucosa, and the prostate. Immunoreactivity determined by radioimmunoassay analysis revealed high secretoneurin
levels in the anterior and posterior pituitary and lower levels in pancreatic and thyroid tissue. A strong secretoneurin immunoreactivity
was also found in ganglion cells of the submucdsal and myenteric plexus of the gastrointestinal tract, and in ganglionic cells
of dorsal root ganglia, peripheral nerves, and ganglion cells of the adrenal medulla. Thus, secretoneurin may serve as a useful
marker of gangliocytic/neuronal differentiation. 相似文献
103.
†K. Babinski P. Haddad D. Vallerand N. McNicoll A. De Léan † H. Ong 《Journal of neurochemistry》1995,64(3):1080-1087
Abstract: There is increasing evidence that members of the natriuretic peptide family display sympathoinhibitory activity, but it remains uncertain which receptor pathway is implicated. We performed cyclic GMP production studies with chromaffin cells treated with either atrial natriuretic factor (ANF) or C-type natriuretic peptide (CNP) and found that these cells specifically express the ANF-R1C but not the ANF-R1A receptor subtype. Evidence for the existence of ANF-R2 receptors was obtained from patch-clamp experiments where C-ANF, an ANF-R2-specific agonist, inhibited nicotinic currents in single isolated chromaffin cells. Involvement of ANF-R2 receptors in the modulation of nicotinic currents was further supported by the significant loss of this inhibitory activity after the cleavage of the disulfide-bridged structure of C-ANF. This linearized form of C-ANF also displayed a lower binding affinity for ANF-R2 receptors. Like the patch-clamp studies, secretion experiments demonstrated that both CNP and C-ANF are equally effective in reducing nicotine-evoked catecholamine secretion by cultured chromaffin cells, raising the possibility that this effect of CNP is predominantly mediated by the ANF-R2 and not the ANF-R1C receptors. Finally, this response appears to be specific to nicotinic agonists because neither histamine- nor KCI-induced secretions were affected by natriuretic peptides. In the present study, we report (1) the presence of ANF-R1C and ANF-R2 receptor subtypes in bovine chromaffin cells, (2) the inhibition by natriuretic peptides of nicotinic whole-cell currents as well as nicotine-induced catecholamine secretion, (3) the possible mediation of these effects by the ANF-R2 class of receptors, and (4) the specificity of this inhibition to nicotinic agonists. Because bovine chromaffin cells release ANF, BNP, and CNP together with catecholamines, all three peptides might exert negative feedback regulation of catecholamine secretion in an autocrine manner by interacting with the nondiscriminating ANF-R2 receptor subtype. 相似文献
104.
J. Hoffmann I. ?ezní?èková S. Vaňòková J. Kupec 《International biodeterioration & biodegradation》1997,39(4):327-332
Several ways or methods of testing the biological degradability of organic substances poorly soluble in aqueous environments were verified by applying manometric BOD measurements. Model substrates employed here were dibutyl phthalate, dioctyl adipate, bio-fuel and some of their components. Dosages of substrates were varied by combining direct weighing and sonification, by using an emulsion with Triton X100, or by a solution in 1,1,2-trichlorotrifluoroethane. These selected variants of dosage, except for the last, proved to be equivalent from the viewpoint of degree and rate of biological degradation. The applied methods gave values of biochemical/theoretical oxygen demand ratio (BOD/ThOD) around 50%, even for substrates claimed to be biologically easily degradable. 相似文献
105.
Roman Bo?a Peter Baran L'ubor Dlháň Hartmut Fuess Wolfgang Haase Franz Renz Wolfgang Linert Ingrid Svoboda Rüdiger Werner 《Inorganica chimica acta》1997,260(2):4119-136
The structure of the [Fe(bzimpy)2](ClO4)2·xH2O system (x = 0.25) was determined by single crystal X-ray structure analysis. The Fe(II) ion is hexacoordinated by six donor nitrogen atoms. The magnetic properties of the complex were investigated by powder magnetic susceptibility measurements and ESR. The freshly prepared sample does not show any traces of iron(III) impurities but these are formed as a function of time. After 1 year the sample contains 8.2% iron(III) as shown by UV spectroscopy and indicated by geff = 4.3 and 2.0 in its ESR spectrum. This explains the recorded ξ versus T behaviour at low temperature: with increasing temperature the ξ value decreases according to the Curie-Weiss law for a S = 5/2 system having an effective g = 4.3. Above 220 K a continuous increase in the ξ value is observed and a spin crossover applies. The spin transition is not complete at room temperature. A pronounced hysteresis is observed upon heating/cooling the sample between 220 and 414 K on the basis of magnetic data and infrared spectra. 相似文献
106.
High performance liquid chromatography analysis of immunoaffinity-purified extracts of mycelia of Amanita muscaria, and the Amaranthus bioassay of the eluted fractions, revealed the following seven cytokinins: zeatin, zeatin riboside, zeatin N-9-glucoside, dihydrozeatin, dihydrozeatin riboside, isopentenyl adenine, and isopentenyl adenosine. The decreased growth of aluminum-treated mycelia correlated with a 35% decrease in the total amount of the cytokinins. Among individual cytokinins, zeatin was the most affected, exhibiting a reduction of about 90%. The results are compared with previous investigations of aluminum effects on cytokinins in the mycelia of Lactarius piperatus, whose growth is stimulated by aluminum.Abbreviations ZR
zeatin riboside
- iPA
isopentenyl adenosine
- Z
zeatin
- DHZ
dihydrozeatin
- iP
isopentenyl adenine
- DHZR
dihydrozeatin riboside
- Z-9G
zeatin N-9-glucoside
- iP-9G
isopentenyl N-9-glucoside
- HPLC
high performance liquid chromatography
- DHZRMP
dihydrozeatin riboside monophosphate
- ZRMP
zeatin riboside monophosphate 相似文献
107.
Eva Pocsik Rudolf Mihalik Maria Penzes Hansruedi Loetscher Harald Gallati Bharat B. Aggarwal 《Journal of cellular biochemistry》1995,59(3):303-316
The cell cycle has been shown to regulate the biological effects of human tumor necrosis factor (TNF), but to what extent that regulation is due to the modulation of TNF receptors is not clear. In the present report we investigated the effect of the cell cycle on the expression of surface and soluble TNF receptors in human histiocytic lymphoma U-937. Exposure to hydroxyurea, thymidine, etoposide, bisbensimide, and democolcine lead to accumulation of cells primarily in G1/S, S, S/G2/M, G2/M, and M stages of the cell cycle, respectively. Whilie no significant change in TNF receptors occurred in cells arrested in G1/S or S/G2 stages, about a 50% decrease was observed in cells at M phase of the cycle. Scatchard analysis showed a reduction in receptor number rather than affinity. In contrast, cells arrested at S phase (thymidine) showed an 80% increase in receptor number. The decrease in the TNF receptors was not due to changes in cell size or protein synthesis. The increase in receptors, however, correlated with an increase in total protein synthesis (to 3.8-fold of the control levels). A proportional change was observed in the p60 and p80 forms of the TNF receptors. A decrease in the surface receptors in cells arrested in M phase correlated with an increase in the amount of soluble receptors. The cellular response to TNF increased to 8- and 2-fold in cells arrested in G1 and S phase, respectively; but cells at G2/M phase showed about 6-fold decrease in response. In conclusion, our results demonstrate that the cell cycle plays an important role in regulation of cell-surface and soluble TNF receptors and also in the modulation of cellular response. © 1995 Wiley-Liss, Inc. 相似文献
108.
The reproductive tracts of 89 female subantarctic fur seals, taken at Gough Island between November 1977 and October 1978, were examined. Females started ovulating at age 4 yr and all 6-yr-old females were sexually mature. They are mono-ovulatory, alternating between ovaries, and only single embryos were found. Females older than 13 yr ( n = 11) showed poor follicular development and some failed to ovulate. The gestation period (first recorded ovulation to first recorded birth) was 360 d, while delayed implantation (first recorded ovulation to first recorded implantation) lasted for 139 days. Follicle numbers in the functional ovary declined sharply after ovulation while the corpus luteum increased in size until at least 1 mo prior to parturition. The number of follicles in the contralateral ovary increased after midwinter (June/July), and the mean size of the largest follicles peaked prior to ovulation in December. The mean size of the largest follicles increased in both ovaries near implantation time, after reaching a low subsequent to, ovulation. The regressing corpus albicans, conspicuous for approximately 3 mo after parturition, could not be detected macroscopically within one year postpartum. Subantarctic fur seals at Gough Island have a distinct postreproductive class of older females. The pregnancy rate for all females ≥4 yr of age was 79%, and it was 84.5% for the sexually mature group of ≥6 yr of age, while the mean age at puberty was 4.80 yr. 相似文献
109.
Changes in DNA supertwist as a response of Bacillus subtilis towards different kinds of stress 总被引:1,自引:0,他引:1
Abstract The silent parD ( kis/kid ) stability operon of plasmid R1 is normally repressed by the co-ordinated action of the Kis and Kid proteins. In this report it is shown that a mutation in repA , the gene of the plasmid replication protein, that reduces two-fold the copy number of the plasmid, leads to the derepression of the parD system. This derepression can be prevented by a suppressor mutation in copB, a copy number control gene of plasmid R1, that increases the efficiency of replication of the repA mutant. Derepression of the wild-type parD system leads to high plasmid stability. These data show the activation of a plasmid stability operon by a mutation that reduces the efficiency of wild-type plasmid replication. 相似文献
110.