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排序方式: 共有3421条查询结果,搜索用时 15 毫秒
71.
Giulia Schiroli Anastasia Conti Samuele Ferrari Lucrezia della Volpe Aurelien Jacob Luisa Albano Stefano Beretta Andrea Calabria Valentina Vavassori Patrizia Gasparini Eralda Salataj Delphine Ndiaye-Lobry Chiara Brombin Julie Chaumeil Eugenio Montini Ivan Merelli Pietro Genovese Luigi Naldini Raffaella Di Micco 《Cell Stem Cell》2019,24(4):551-565.e8
72.
Comes S Locascio A Silvestre F d'Ischia M Russo GL Tosti E Branno M Palumbo A 《Developmental biology》2007,306(2):772-784
Metamorphosis in the ascidian Ciona intestinalis is a very complex process which converts a swimming tadpole to an adult. The process involves reorganisation of the body plan and a remarkable regression of the tail, which is controlled by caspase-dependent apoptosis. However, the endogenous signals triggering apoptosis and metamorphosis are little explored. Herein, we report evidence that nitric oxide (NO) regulates tail regression in a dose-dependent manner, acting on caspase-dependent apoptosis. An increase or decrease of NO levels resulted in a delay or acceleration of tail resorption, without affecting subsequent juvenile development. A similar hastening effect was induced by suppression of cGMP-dependent NO signalling. Inhibition of NO production resulted in an increase in caspase-3-like activity with respect to untreated larvae. Detection of endogenously activated caspase-3 and NO revealed the existence of a spatial correlation between the diminution of the NO signal and caspase-3 activation during the last phases of tail regression. Real-time PCR during development, from early larva to early juveniles, showed that during all stages examined, NO synthase (NOS) is always more expressed than arginase and it reaches the maximum value at late larva, the stage immediately preceding tail resorption. The spatial expression pattern of NOS is very dynamic, moving rapidly along the body in very few hours, from the anterior part of the trunk to central nervous system (CNS), tail and new forming juvenile digestive organs. NO detection revealed free diffusion from the production sites to other cellular districts. Overall, the results of this study provide a new important link between NO signalling and apoptosis during metamorphosis in C. intestinalis and hint at novel roles for the NO signalling system in other developmental and metamorphosis-related events preceding and following tail resorption. 相似文献
73.
Hyperpolarization-activated cyclic nucleotide-sensitive (HCN) channels mediate the I(f) current in heart and I(h) throughout the nervous system. In spiking neurons I(h) participates primarily in different forms of rhythmic activity. Little is known, however, about its role in neurons operating with graded potentials as in the retina, where all four channel isoforms are expressed. Intriguing evidence for an involvement of I(h) in early visual processing are the side effects reported, in dim light or darkness, by cardiac patients treated with HCN inhibitors. Moreover, electroretinographic recordings indicate that these drugs affect temporal processing in the outer retina. Here we analyzed the functional role of HCN channels in rod bipolar cells (RBCs) of the mouse. Perforated-patch recordings in the dark-adapted slice found that RBCs exhibit I(h), and that this is sensitive to the specific blocker ZD7288. RBC input impedance, explored by sinusoidal frequency-modulated current stimuli (0.1-30 Hz), displays band-pass behavior in the range of I(h) activation. Theoretical modeling and pharmacological blockade demonstrate that high-pass filtering of input signals by I(h), in combination with low-pass filtering by passive properties, fully accounts for this frequency-tuning. Correcting for the depolarization introduced by shunting through the pipette-membrane seal, leads to predict that in darkness I(h) is tonically active in RBCs and quickens their responses to dim light stimuli. Immunohistochemistry targeting candidate subunit isoforms HCN1-2, in combination with markers of RBCs (PKC) and rod-RBC synaptic contacts (bassoon, mGluR6, Kv1.3), suggests that RBCs express HCN2 on the tip of their dendrites. The functional properties conferred by I(h) onto RBCs may contribute to shape the retina's light response and explain the visual side effects of HCN inhibitors. 相似文献
74.
Ammar Bader Lirio Panizzi Pier Luigi Cioni Guido Flamini 《Central European Journal of Biology》2007,2(2):206-212
The composition of the essential oils obtained from the leaves and the flowers of Achillea ligustica (Asteraceae) growing in Sicily has been studied. The main constituents of the leaves were 4-terpineol (19.3%), carvone (8.9%),
γ-terpinene (7.2%) and β-phellandrene (6.8%). 4-terpineol (12.0%), carvone (10.0%), and β-phellandrene (5.4%), along with linalool (20.4%) and cedrol (4.3%) were detected in the flower’s oil. Furthermore, the antimicrobial
activity of the essential oils and of some of the main constituents were assayed on bacteria and fungi.
In memory of Prof. Ivano Morelli (1940–2005) 相似文献
75.
Seasonal variation of the chemical constituents of the essential oil of Santolina etrusca from Italy
The seasonal variation of the essential oil, in terms of both yield and composition, of a population of Santolina etrusca (Asteraceae) is reported in detail for different aerial parts, including sterile branches, fertile branches, and capitula. The yields generally increased from November to June, and then decreased in August and September. The main constituents of the sterile branches were 1,8-cineole and viridiflorol. The oil from fertile branches was characterized by myrcene as principal compound, whereas the essential oil obtained from the capitula contained germacrene D as the main constituent. Several compounds, as identified by GC and GC/MS, were found to prevail during the cold season. 相似文献
76.
Matthew A Schrager E Jeffrey Metter Eleanor Simonsick Alessandro Ble Stefania Bandinelli Fulvio Lauretani Luigi Ferrucci 《Journal of applied physiology》2007,102(3):919-925
The aging process is often paralleled by decreases in muscle and increases in fat mass. At the extreme these two processes lead to a condition known as "sarcopenic obesity" (Roubenoff R. Ann NY Acad Sci 904: 553-557, 2000). Research suggests that inflammatory cytokines produced by adipose tissue, especially visceral fat, accelerate muscle catabolism and thus contribute to the vicious cycle that initiates and sustains sarcopenic obesity. We tested the hypothesis that obesity and poor muscle strength, hallmarks of sarcopenic obesity, are associated with high circulating levels of proinflammatory cytokines in a random sample of the residents of two municipalities in the Chianti geographic area (Tuscany, Italy). The study sample consisted of 378 men and 493 women 65 yr and older with complete data on anthropometrics, handgrip strength, and inflammatory markers. Participants were cross-classified according to sex-specific tertiles of waist circumference and grip strength and according to a cut point for obesity of body mass index > or =30 kg/m(2). After adjusting for age, sex, education, smoking history, physical activity, and history of comorbid diseases, components of sarcopenic obesity were associated with elevated levels of IL-6, C-reactive protein, IL-1 receptor antagonist, and soluble IL-6 receptor (P < 0.05). Our findings suggest that global obesity and, to a greater extent, central obesity directly affect inflammation, which in turn negatively affects muscle strength, contributing to the development and progression of sarcopenic obesity. These results suggest that proinflammatory cytokines may be critical in both the development and progression of sarcopenic obesity. 相似文献
77.
Mirella Georgouli Cecilia Herraiz Eva Crosas-Molist Bruce Fanshawe Oscar Maiques Anna Perdrix Pahini Pandya Irene Rodriguez-Hernandez Kristina M. Ilieva Gaia Cantelli Panagiotis Karagiannis Silvia Mele Hoyin Lam Debra H. Josephs Xavier Matias-Guiu Rosa M. Marti Frank O. Nestle Jose L. Orgaz Victoria Sanz-Moreno 《Cell》2019,176(4):757-774.e23
78.
Giovanni Mantovani Vittorio Gebbia Mario Airoldi Cesare Bumma Paolo Contu Alessandro Bianchi Massimo Ghiani Daniela Dessì Elena Massa Luigi Curreli Biancarosa Lampis Paola Lai Carlo Mulas Antonio Testa Ernesto Proto Gabrio Cadeddu Giorgio Tore 《Cancer immunology, immunotherapy : CII》1998,47(3):149-156
We carried out an open, randomized, phase III, multicenter clinical trial to compare, in neo-adjuvant setting, the clinical
response and toxicity of the combination chemotherapy cisplatin + 5-FU with the same combination plus s.c. recombinant interleukin-2
(rIL-2) in patients with advanced (stage III–IV) head and neck squamous-cell carcinoma (HNSCC). Regimen A was the classical
Al Sarraf treatment: 100 mg/m2 cisplatin i.v. on day 1 plus 1000 mg m−2 day−1 5-FU on days 1–5 as a continuous infusion. Regimen B was the same as regimen A plus 4.5 MIU/day rIL-2 s.c. on days 8–12 and
15–19. Treatment was repeated every 3 weeks for three cycles. A total of 33 patients were enrolled in the study; 30 were evaluable
for toxicity and 28 for response. Seventeen patients were assigned to group A and 16 were assigned to group B. Three patients
(20%) of group A and 4 (31%) of group B had a complete response, 9 patients (60%) of group A and 6 (46%) of group B had a
partial response, with an overall response rate of 12 patients (80%) for group A and 10 patients (77%) for group B. Two patients
(13%) of group A and 3 patients (23%) group B had stable disease; 1 patient (7%) of group A had progressive disease. Thus,
there was not a statistically significant difference in response rate between the two groups and therefore there was no benefit
from the addition of immunotherapy with rIL-2 to the standard chemotherapy. Both regimens were well tolerated. There were
2 toxic deaths (6.7%), 1 from hematological causes in group A and 1 from cardiac causes in group B. Myelosuppression and gastrointestinal
toxicity, mainly nausea/vomiting and stomatitis, were the most frequent toxicities. The calculated number of patients for
the sample has not yet been reached; however, the projection of our present results suggests that it is highly improbable
that a clinically significant difference between the two treatment groups will be observed even if the calculated patient
sample size is achieved.
Received: 9 April 1998 / Accepted: 30 June 1998 相似文献
79.
Castelli MP Ferraro L Mocci I Carta F Carai MA Antonelli T Tanganelli S Cignarella G Gessa GL 《Journal of neurochemistry》2003,87(3):722-732
Two gamma-hydroxybutyric acid (GHB) analogues, trans-gamma-hydroxycrotonic acid (t-HCA) and gamma-(p-methoxybenzyl)-gamma-hydroxybutyric acid (NCS-435) displaced [3H]GHB from GHB receptors with the same affinity as GHB but, unlike GHB, failed to displace [3H]baclofen from GABAB receptors. The effect of the GHB analogues, GHB and baclofen, on G protein activity and hippocampal extracellular glutamate levels was compared. While GHB and baclofen stimulated 5'-O-(3-[35S]thiotriphospate) [35S]GTPgammaS binding both in cortex homogenate and cortical slices, t-HCA and NCS-435 were ineffective up to 1 mm concentration. GHB and baclofen effect was suppressed by the GABAB antagonist CGP 35348 but not by the GHB receptor antagonist NCS-382. Perfused into rat hippocampus, 500 nm and 1 mm GHB increased and decreased extracellular glutamate levels, respectively. GHB stimulation was suppressed by NCS-382, while GHB inhibition by CGP 35348. t-HCA and NCS-435 (0.1-1000 microm) locally perfused into hippocampus increased extracellular glutamate; this effect was inhibited by NCS-382 (10 microm) but not by CGP 35348 (500 microm). The results indicate that GHB-induced G protein activation and reduction of glutamate levels are GABAB-mediated effects, while the increase of glutamate levels is a GHB-mediated effect. Neither t-HCA nor NCS-435 reproduced GHB sedative/hypnotic effect in mice, confirming that this effect is GABAB-mediated. The GHB analogues constitute important tools for understanding the physiological role of endogenous GHB and its receptor. 相似文献
80.
Candussio L Decorti G Crivellato E Granzotto M Rosati A Giraldi T Bartoli F 《Life sciences》2002,71(26):3109-3119
The effect of a chronic treatment with low oral doses of verapamil, a calcium channel blocker commonly employed in cardiovascular therapy, on doxorubicin toxicity, was evaluated in CD1 mice. Verapamil, administered at a dosage corresponding to a typical cardiovascular posology in humans, significantly increased doxorubicin toxicity. In particular the mortality was significantly higher and earlier and histological analysis revealed an increase in the severity of lesions in the liver, kidney and small bowel of verapamil pretreated animals. The pharmacokinetic profiles revealed that verapamil treated group had higher doxorubicin peak plasma and tissue levels and AUCs.This study shows that verapamil, administered at low doses, dramatically increases doxorubicin toxicity, probably through an interaction between the two drugs, both P-glycoprotein substrates, on the protein expressed in normal tissues, and suggests caution in the use of the calcium channel blocker for cardiovascular pathologies in patients who have to be treated with antineoplastic agents, substrates of P-glycoprotein. 相似文献