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981.
Induction of accessory cell function of human alveolar macrophages by inhalation of human natural interleukin-2 总被引:1,自引:0,他引:1
Gernot Zissel Walter E. Aulitzky J. Lorenz Christoph Huber J. Müller-Quernheim 《Cancer immunology, immunotherapy : CII》1996,42(2):122-126
Accessory function allows antigen-presenting cells to produce sufficient secondary signals for optimum T cell proliferation
and interleukin-2 (IL-2) production. Alveolar macrophages are inferior accessory cells compared to monocytes (PBM). We report
here that the accessory index (AI) of alveolar macrophages and PBM of patients with lung metastases of solid tumors treated
with inhalations of human natural IL-2 (hnIL-2) increased following its administration (P<0.005). The accessory index was significantly elevated from baseline values after 2 weeks of inhalation of 300 000 IU hnIL-2/day
(8.2±10.2 compared to 1.1±1; P<0.001). The inhalation of 150 000 IU also induced increases in the index (AI = 2.3±1.9), however, without reaching statistical
significance. In addition at 300 000 IU IL-2/day a significant increase in the accessory index was observed for PBM (4±2.5;
P<0.05). The indices of PBM and alveolar macrophages prior to inhalation showed a significant negative correlation with the
age of the patients (r
s = – 0.5; r
s = – 0.8, respectively; P<0.03 for all comparisons). Our data demonstrate that the inhalational application of hnIL-2 enhances the accessory function
of alveolar macrophages and, to lesser extent, the accessory index of PBM, indicating the occurrence of pharmacological immunostimulation.
Received: 16 August 1995 / Accepted: 4 January 1996 相似文献
982.
983.
984.
Belgin Küçükkaya Goncagül Haklar Prof. Dr. A. Süha Yalçin 《Neurochemical research》1996,21(12):1535-1538
NMDA, the specific agonist of glutamate gated ion channels permeable to calcium, is implicated as a causal factor in the pathogenesis
of several neurobiological disorders such as stroke, seizures, ischemia, and chronic neurodegenerative disease. On the other
hand, evidence on the roles of oxidative mechanisms involved in NMDA-induced neurotoxicity is accumulating. In this study,
we have used chemiluminescence measurements as an easy, rapid and sensitive assay to investigate the effects of NMDA and oxidative
stress on brain cell vulnerability. Rat brain homogenates were incubated with increasing concentrations of glutamate and NMDA.
Production of reactive oxygen species was followed by single photon emission measurements using the specific enhancers luminol
and lucigenin. Increases in emission were observed at excitotoxic concentrations of glutamate and NMDA. Other parameters of
oxidative stress such as diene conjugates, TBARS and carbonyl groups were also investigated. Our results indicated that chemiluminescence
measurements may be used to study involvement of oxidative stress in neurotoxicity. 相似文献
985.
B. M. Culik K. Pütz R. P. Wilson C. A. Bost Y. Le Maho J. -L. Verselin 《Polar Biology》1996,16(5):371-378
Core temperature was determined in two king penguins living in the wild at Ile de la Possession, Crozel Archipelago, using
implantable four-channel temperature loggers. Core temperatures derived from bird no. 1 (sensor placed under the sternum,
in the vicinity of the liver and upper stomach) were closely correlated with diving activity (as determined by an external
light recorder), and ranged from 38.3°C, (on land) to a minimum of 37.2°C during a dive. Core temperatures measured in bird
no. 2 showed that temperatures near the heart were generally 1°C lower than those under the sternum or in the lower abdomen.
Core temperatures declined continuously during dives (by 0.8, 1.2 and 2.7°C in the lower abdomen, under the sternum and near
the heart, respectively) and showed precipitous drops to 35°C, probably associated with ingestion of food. Temperatures measured
near the heart fluctuated over a period of 288 s, corresponding to the duration (from the literature) of the surface/dive
cycle. The relevance of these findings with respect to diving physiology, blood perfusion of tissues, tissue metabolism and
aerobic dive limits is discussed. 相似文献
986.
H. Sztajer W. Wang H. Lünsdorf A. Stocker R. D. Schmid 《Applied microbiology and biotechnology》1996,45(5):600-606
Geotrichum candidum was found to produce a lactate oxidase. The enzyme was purified by gel filtration and ion-exchange chromatography. The purified
lactate oxidase showed a molecular mass of 50 kDa under denaturing and about 400 kDa under non-denaturing conditions. Transmission
electron micro-scopy analysis confirmed an octameric structure. FMN was found to be a cofactor for this enzyme. Polarographic
studies confirmed an oxygen uptake by the lactate oxidase. The enzyme showed specificity towards the L isomer of lactate and
did not oxidise pyruvate, fumarate, succinate, maleate and ascorbate. It was stable at alkaline pH and also for 15 min at
45°C. The addition of glycerol and dextran 500 000 to the enzyme sample enhanced storage stability.
Received: 28 September 1995/Received revision: 10 January 1996/Accepted: 15 January 1996 相似文献
987.
H. E. Valentin A. Schönebaum A. Steinbüchel 《Applied microbiology and biotechnology》1996,46(3):261-267
A recombinant strain of Pseudomonas putida GPp104 (pHP1014::E146), which expressed the polyhydroxyalkanoic acid (PHA) synthase of Thiocapsa pfennigii exhibiting an unusual substrate specificity at a high level was incubated in two-stage batch or fed-batch accumulation experiments
with 5-hydroxyhexanoic acid (5HHx) as carbon source in the second cultivation phase, copolyesters of 3-hydroxybutyric acid
(3HB) plus 5HHx, or of 3HB, 3-hydroxyhexanoic acid (3HHx) plus 5HHx were accumulated as revealed by gas-chromatographic and
13C-NMR spectroscopic analysis. When the recombinant P. putida GPp104 was incubated with 4-hydroxyheptanoic acid (4HHp) as carbon source in the second cultivation phase, a copolyester
consisting of 3HB, 3-hydroxyvaleric acid and 3- and 4-hydroxyheptanoic acid accumulated. Providing 4-hydroxyoctanoic acid
as carbon source in the second cultivation phase led to the accumulation of a polyester that contained 1–2 mol% 4-hydroxyoctanoic
acid besides 3-hydroxyoctanoic acid, 3HHx, 3-hydroxyvaleric acid and 3HB. In addition to PHA containing these new constituents,
PHA with 4-hydroxyvaleric acid was accumulated from laevulinic acid. Eleven strains from five genera have been also analysed
for their ability to utilize different carbon sources for colony growth, which might serve as potential precursors for the
biosynthesis of PHA with unusual constituents. Although most of the carbon sources were utilized by some strains for colony
growth, accumulation experiments gave no evidence for the accumulation of new PHA by these wild-type strains.
Received: 22 April/Received revision: 23 May 1996/Accepted: 2 June 1996 相似文献
988.
Hoch Brigitte Lutsch Gudrun Schlegel Wolfgang-Peter Stahl Joachim Wallukat Gerd Bartel Sabine Krause Ernst-Georg Benndorf Rainer Karczewski Peter 《Molecular and cellular biochemistry》1996,160(1):231-239
Recent investigations concentrate on the correlation between the myocardial expression of the inducible 70-kDa heat shock protein (HSP70i) by different stress conditions and its possible protective effects. Only few studies have focused on the involvement of small heat shock proteins in this process. We analyzed the location of the small heat shock protein HSP25 in isolated cardiomyocytes as well as its location and induction in isolated perfused hearts of rats. By immunofluorescence microscopy HSP25 was found to colocalize with actin in the I-band of myofibrils in cardiomyocytes of isolated perfused hearts as well as in isolated neonatal and adult cardiomyocytes. Hyperthermic perfusion of isolated hearts for 45 min resulted in modulation of different parameters of heart function and in induction of HSP25 and HSP70i. Temperatures higher than 43°C (44–46°C) were lethal with respect to the contractile function of the hearts. Compared to control hearts perfused at 37°C, significant increases during hyperthermic perfusion at 42°C and 43°C were obtained for heart rate, contraction velocity and relaxation velocity. In response to hyperthermia at 43°C and after subsequent normothermic perfusion for 135 min at 37°C, left ventricular pressure, contraction velocity and relaxation velocity remained significantly elevated. However, heart rate returned to control values immediately after the period of heat treatment. HSP25 is constitutively expressed even in normothermic perfused hearts as shown by Western blotting. Hyperthermia increased the content of HSP25 only in the left ventricular tissue. In contrast, HSP70i was strongly induced in all analyzed parts of the myocardium (left ventricle, right ventricle, septum). Our findings suggest a differential regulation of HSP25 and HSP70i expression in response to hyperthermia in isolated perfused hearts. The constitutively expressed HSP25 seems to be located adjacent to the myofibrils which implies a specific role of this protein even under unstressed conditions for the contractile function of the myocardium. 相似文献
989.
Eberhard Fuchs Jan-Christian Wasmuth Gabriele Flügge Gerald Huether Raphael Troost Jürgen Beyer 《Cellular and molecular neurobiology》1996,16(1):21-37
Summary 1. Corticotropin-releasing factor (CRF) is thought to be involved in the regulation of the diurnal activity of the hypothalamus-pituitary-adrenal
(HPA) axis and to act as a neurotransmitter in the brain. To date it is unknown whether the binding sites of the central CRF
system are subject to diurnal variations.
2. We measured the number of CRF binding sites over the course of a complete 24-hr light-dark cycle in the pituitary, amygdala,
bed nucleus of the stria terminalis (BNST), cingulate cortex, visceral cortex, paraventricular nucleus of the hypothalamus,
hippocampus, and locus ceruleus of rats byin vitro receptor autoradiography with iodinated ovine CRF. A 24-hr time course was also established for plasma CRF and corticosterone.
3. The diurnal pattern of plasma CRF does not correlate with the pattern of plasma corticosterone. Within the brain, CRF binding
in the basolateral nucleus of the amygdala showed a U-shaped curve with maximum levels in the morning and a wide hallow between
1500 and 0100. A biphasic profile with a small depression in the afternoon and a more pronounced depression in the second
half of the activity period is characteristic for the other brain areas and the pituitary. The profile for the pituitary correlates
with those for the BNST and the area of the locus ceruleus. Furthermore, the diurnal pattern of CRF binding sites in the BNST
correlates with that of the hippocampus, and the daytime pattern of the visceral cortex is similar to that of both the hippocampus
and the BNST.
4. Since the CRF-binding profiles in the brain and the pituitary clearly differ from the profiles of both plasma CRF and corticosterone,
one may assume that the diurnal pattern of central CRF binding sites is not directly coupled to the activity of the HPA axis. 相似文献
990.
Henning Ursula Wallukat Gerd Holtzhauer Martin 《Molecular and cellular biochemistry》1996,160(1):47-52
In primary cultures of neonatal rat heart cells we found a linear correlation between the number of L-type calcium channel-specific dihydropyridine (DHP) binding sites and spontaneous beating frequency (v).Formation of glycoproteins in tissue culture was suppressed by different inhibitors of N-glycosylation. This inhibition alters to a different extent the binding of the DHP ligand (+)-[methyl-3H]PN 200-110 and v. The most severe but reversible effect occurs at 6 g/ml tunicamycin (Bmax 45% and v 6%, resp., of control), a slight increase in Bmax at 0.1–0.5 mM castanospermine and 0.05–2.5 mM deoxymannojirimycin. The other inhibitors gave no significant alterations of Bmax. 相似文献