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101.
Kazuko Wada Shintaro Nomura Eiichi Morii Yukihiko Kitamura Yasuko Nishizawa Akira Miyake Nobuyuki Terada 《The Journal of steroid biochemistry and molecular biology》1996,59(5-6):367-375
To examine the roles played by transforming growth factors (TGF)-β1, -β2, -β3, and TGF-β type II receptors in the induction of apoptosis in the mouse uterine epithelium after estrogen deprivation, we investigated the expression of their mRNAs and the mRNA of sulfated glycoprotein-2 (SGP-2). Pellets containing 100 μg estradiol-17β (E2) were implanted into ovariectomized mice and removed four days later. Apoptotic indices (percentage of apoptotic cells) of both luminal and glandular epithelia increased after E2 pellets were removed, but administration of progesterone (P), 5-dihydrotestosterone (DHT), or continued implantation of E2 pellets suppressed this increase. Levels of mRNAs of TGF-β1, -β2, and -β3, and SGP-2 did not increase after estrogen deprivation. However, estrogen deprivation caused a gradual increase in the level of TGF-β type II receptor mRNA, and its level increased about six-fold six days later. Moreover, E2, P, and DHT markedly decreased the level of TGF-β type II receptor mRNA. In situ hybridization demonstrated that mRNAs of TGF-β1, -β2, -β3 and TGF-β type II receptor were localized to the epithelium. Exogenous administration of TGF-β1 into the uterine stroma induced apoptosis in the epithelium, a finding that suggests that signals produced by TGF-βs can induce apoptosis. Therefore, the present results suggest that increased sensitivity of uterine epithelial cells to TGF-βs, as demonstrated by an increase in TGF-β type II receptor mRNA, is involved in the induction of apoptosis after estrogen deprivation, although signals produced by TGF-βs do not appear sufficient to induce apoptosis. 相似文献
102.
Fumi Katoh Kazuo Kitamura Hiromi Niina Ryuichi Yamamoto Hisanori Washimine †Kenji Kangawa Yoshitaka Yamamoto Hideyuki Kobayashi Tanenao Eto Akihiko Wada 《Journal of neurochemistry》1995,64(1):459-461
Abstract: In cultured bovine adrenal medullary cells, stimulation of nicotinic receptors by carbachol evoked the Ca2+ -dependent exocytotic cosecretion of proadrenomedullin N-terminal 20 peptide (PAMP) (EC50 = 50.1 µ M ) and catecholamines (EC50 = 63.0 µ M ), with the molar ratio of PAMP/catecholamines secreted being equal to the ratio in the cells. Addition of PAMP[1–20]NH2 inhibited carbachol-induced 22 Na+ influx via nicotinic receptors (IC50 = 2.5 µ M ) in a noncompetitive manner and thereby reduced carbachol-induced 45 Ca2+ influx via voltage-dependent Ca2+ channels (IC50 = 1.0 µ M ) and catecholamine secretion (IC50 = 1.6 µ M ). It did not alter high K+ -induced 45 Ca2+ influx via voltage-dependent Ca2+ channels or veratridine-induced 22 Na+ influx via voltage-dependent Na+ channels. PAMP seems to be a novel antinicotinic peptide cosecreted with catecholamines by a Ca2+ -dependent exocytosis in response to nicotinic receptor stimulation. 相似文献
103.
Y. Kobayashi Yufuko Takahashi Satoshi Chikayama Motomi Ikeda Nobuhiko Uoshima Shinya Kimura Koji Tanaka Katuya Wada Masaru Ozawa Tatuo Sugano Naoyuki Maruo Motoharu Kondo 《Histochemistry and cell biology》1997,108(2):115-120
We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone
marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed
by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole
(DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were
changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional
to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when
megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls,
the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced
0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients,
the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore,
this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients.
Accepted: 29 April 1997 相似文献
104.
105.
Changes of an androgen-dependent nuclear protein during functional differentiation and by dedifferentiation of the dorsolateral prostate of rats 总被引:1,自引:0,他引:1
Y Matuo N Nishi Y Tanaka Y Muguruma K Tanaka Y Akatsuka S I Matsui A A Sandberg F Wada 《Biochemical and biophysical research communications》1984,118(2):467-473
In contrast with previous results that indicate that Saccharomyces cerevisiae fructose-1,6-bisphosphatase is a dimer of 56,000 molecular weight subunits, we find that the subunit Mr of the enzyme purified from baker's yeast is 40,000. The same subunit Mr was observed in immunoprecipitates of crude supernatants of baker's yeast and S. cerevisiae cultures, as well as in acid-extracts of cells detected by immunoblotting, suggesting that the native subunit indeed has a Mr of 40,000 and it has not been produced from a larger polypeptide. Complete immunoprecipitation of fructose-1,6-bisphosphatase activity with saturating concentrations of specific antibody suggests that there is only one fructose-1,6-bisphosphatase isozyme in S. cerevisiae. The Mr of the purified enzyme determined by size exclusion HPLC suggests that it has a tetrameric structure characteristic of fructose-1,6-bisphosphatases from a broad phylogenetic spectrum. 相似文献
106.
A Wada M Okamoto Y Nonaka T Yamano 《Biochemical and biophysical research communications》1984,119(1):365-371
[3H]Corticosterone was incubated with cytochrome P-45011 beta purified to electrophoretic homogeneity from bovine adrenocortical mitochondria, and the reaction products were analyzed by high performance liquid chromatography. The production of aldosterone (21.2 pmol/nmol P-450/min) and 18-hydroxycorticosterone (1.17 nmol/nmol P-450/min) was observed. When lipidic extracts from mitochondria of bovine adrenocortical zona glomerulosa were added to the reaction mixture, the rate of production of aldosterone was increased 28-fold. When [3H]18-hydroxycorticosterone was incubated with cytochrome P-45011 beta, the amount of aldosterone produced was 55.7 pmol/nmol P-450/min in the absence of the lipidic extracts and the enhancing effect of the lipidic extracts was 4-fold. 相似文献
107.
The lipid phases of the thylakoid and cytoplasmic membranesfrom the blue-green alga, Anacystis nidulans, were studied bya spin-probe method using 2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxyl.The thylakoid and cytoplasmic membranes of this alga were bothin the liquid crystalline state at growth temperature, and inthe phase separation state at about 0?C. The thylakoid membranesentered the phase separation state at a temperature higher thanthe cytoplasmic membranes. The lipid phase of the thylakoidmembranes from Anabaena variabilis was studied in a similarway, and these membranes were found also to undergo the phasetransition. The temperature for the onset of the phase separationand the fluidity of the membrane lipids of both algae dependedon the growth temperature of the culture. (Received April 9, 1984; Accepted June 1, 1984) 相似文献
108.
In Rana pipiens, mating behavior could be induced readily in intact males by several pituitary implantations, but never in castrates. Systemic testosterone injection (1 mg daily), with or without pituitary implantation, failed to restore mating behavior in castrated frogs. On the other hand, intracranial implantation of testosterone (approximately 60-μg pellets in which testosterone is mixed with cholesterol 1:1) in castrates evoked mating behavior, including mating calls and clasping. The most effective implantation site was the rostral part of the preoptic nucleus. Thus, the rostral part of the preoptic nucleus is the androgen-sensitive site which governs sexual behavior in this species. The relative ineffectiveness of systemic injection of testosterone is discussed. 相似文献
109.
Electrodes were implanted chronically into the preoptic areas of normal or castrated male frogs, Rana pipiens, and monopolar monophasic stimulating currents (100 Hz, 0.5-msec duration, and mainly 50–200 μA in intensity) were delivered through the implanted electrodes in freely moving frogs. When the electrodes were placed in the rostral part of the preoptic nucleus, mating calls (mainly trills and sometimes chuckles) were inducible. Fifty microamperes was generally an effective stimulus intensity for induction of calls, and 20 μA was the minimum effective stimulus intensity observed. There was no difference in the threshold to induce calls between pituitary-treated intact and castrated frogs. 相似文献
110.
A noninhibitory medium and GasPack anaerobic culture system were employed for the selective enumeration and isolation of Vibrionaceae in seawater and marine sediments.Vibrio counts obtained by the new method for seawater and sediment samples were compared with vibrio numbers in the heterotrophic bacterial population appearing on a medium routinely employed in the laboratory for such counts. The ratio of the former to the latter counts ranged from 0.5 to 1.3, the average being 0.96. The seawater and sediment bacteria that grew and produced visible colonies on the medium under anaerobic conditions for 3 days at 20°C were almost exclusively vibrios.From the results reported here it is concluded that most of the vibrios present in seawater and sediment samples can be recovered by the new method developed in this study. 相似文献