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排序方式: 共有2368条查询结果,搜索用时 15 毫秒
51.
Cao YN Kitamura K Kato J Kuwasako K Ito K Onitsuka H Nagoshi Y Uemura T Kita T Eto T 《Hypertension》2003,42(3):369-372
The vasodilator peptide adrenomedullin (AM) elicits diuresis and natriuresis and inhibits aldosterone secretion. The aim of this study was to better understand the role of AM in maintaining water and electrolyte balance during chronic salt loading. Male Wistar rats were divided into a high salt (HS) group that received a diet containing 8% sodium chloride (NaCl) and a normal salt group that received a diet containing 0.4% NaCl. Plasma AM concentrations as well as expression of AM mRNA in the adrenal gland and kidney were then measured after 3, 7, 14, and 28 days. After 28 days, sodium and water excretion were significantly higher in HS rats than in control, although blood pressure and fluid volume were not significantly affected. Moreover, although plasma AM remained unchanged for up to 14 days, it was increased 2.5-fold in HS rats after 28 days on a high salt diet, and there were corresponding 3-fold and 1.5-fold increases in the levels of AM mRNA in the adrenal gland and kidney, respectively. At the same time, expression of calcitonin receptor-like receptor mRNA was significantly upregulated in both kidney and adrenal gland, as was expression of receptor activity-modify protein 1 (RAMP1) and RAMP2 mRNA in the adrenals and expression of RAMP3 in kidneys. Taken together, these results suggest that AM plays a role in the regulation of water and electrolyte balance in animals chronically ingesting high levels of salt. 相似文献
52.
53.
Chen L Kawano T Bajic S Kaziro Y Itoh H Art JJ Nakajima Y Nakajima S 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(12):8430-8435
G protein-coupled inward rectifiers (GIRKs) are activated directly by G protein betagamma subunits, whereas classical inward rectifiers (IRKs) are constitutively active. We found that a glutamate residue of GIRK2 (E315), located on a hydrophobic domain of the C terminus, is crucial for the channel activation. This glutamate (or aspartate) residue is conserved in all members of the Kir family. Substitution of alanine for the glutamate on GIRK1, GIRK2, and IRK2, expressed in HEK293 cells, greatly reduced the whole-cell currents. The whole-cell current of GIRK channels with a constitutively active gate, GIRK2(V188A), [Yi, B. A., Lin, Y. F., Jan, Y. N. & Jan, L. Y. (2001) Neuron 29, 657-667] was also reduced by the same glutamate mutation. Mean open time and conductance of single channels in GIRK2 and IRK2 were not affected by the mutation, indicating that the reduced whole-cell current resulted from a lowered probability of channel activation. The mutated GIRK and IRK showed normal trafficking to the cell membrane. The mutated GIRK2 retained the ability to interact with G protein betagamma subunits, and it showed almost the same inwardly rectifying property as the wild type. The mutated GIRK1 and GIRK2 retained ion selectivity to K(+) ions. This glutamate residue corresponds to one of the residues causing Andersen's syndrome [Plaster, N. M., Tawil, R., Tristani-Firouzi, M., Canun, S., Bendahhou, S., Tsunoda, A., Donaldson, M. R., Iannaccone, S. T., Brunt, E., Barohn, R., et al. (2001) Cell 105, 511-519]. Our interpretation is that this region of the glutamate residue is crucial in relaying the activating message from the ligand sensor region to the gate. 相似文献
54.
Morimasa Sekiguchi Yuzo Fujii Atsuko Saito Toshimitsu Suzuki Yasuko Shiroko Hisayoshi Nakamura Ken-ichiro Hasumi 《Journal of gastroenterology》1995,30(5):589-598
We describe a gastric carcinoma cell line that has been maintained in vitro for more than 10 years and retains the capacity
to produce a large amount of alpha-fetoprotein. This cell line was isolated from a metastatic lymph node of a 63-year-old
male patient with advanced gastric carcinoma (T2N3P0H0M0) who showed high serum levels of alpha-fetoprotein. The primary tumor
was moderately differentiated tubular adenocarcinoma and the lymph node was poorly differentiated adenocarcinoma without any
particular pattern. The cultured cells grew as densely packed islet-like colonies with small polygonal cells. Electron microscopy
revealed cells abundant in cytoplasmic organelles, with some cellular attachments being tight with junctional complexes and
some being loose across intercellular spaces. The free cell surface had microvilli. The population doubling-time was 152 h
at passage 58. Chromosomal analysis revealed the modal number to be 77, with numerous karyotype abnormalities. The tumorigenicity
of the cultured cells in athymic nude mice was positive only when they were subcutaneously transplanted beneath a plastic
plate, but when the cells were transplanted subcutaneously or administered by intrasplenic injection in intact or weakly irradiated
nude mice, no tumorigenicty was shown. The cell line produced tumor-associated antigens, such as alpha-fetoprotein, carcinoembryonic
antigen, and tissue polypeptide antigen. This cell line may be useful for comparative studies of different types of gastric
carcinoma and alpha-fetoproteins of different origins. 相似文献
55.
Keiko Toyohara Daigo Yagishita Yoshimichi Kudo Tomomi Nishimura Daiji Takeuchi Yasuko Tomizawa Morio Shoda 《Pacing and clinical electrophysiology : PACE》2021,44(1):181-184
A 42‐year‐old woman with tricuspid atresia who underwent a Fontan surgery (atrio‐pulmonary connection) was admitted to our hospital due to symptomatic ventricular tachycardia (VT). A defibrillation lead was implanted in a distal site of a coronary vein since there was no usual entry to the ventricle. Ventricular pacing was impossible due to the high threshold, however, good sensing was obtained. Three years later, she felt palpitations and a subsequent shock therapy while climbing stairs. The cardioverter data showed that an appropriate cardioversion therapy successfully converted VT to normal rhythm. 相似文献
56.
57.
Yoko Shibata Shuichi Abe Sumito Inoue Akira Igarashi Keiko Yamauchi Yasuko Aida Hiroyuki Kishi Keiko Nunomiya Hiroshi Nakano Masamichi Sato Kento Sato Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《International journal of medical sciences》2013,10(11):1530-1536
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men. 相似文献
58.
59.
HMG-CoA reductase inhibitors promote cholesterol-dependent Akt/PKB translocation to membrane domains in endothelial cells 总被引:5,自引:0,他引:5
Skaletz-Rorowski A Lutchman M Kureishi Y Lefer DJ Faust JR Walsh K 《Cardiovascular research》2003,57(1):253-264
OBJECTIVE: Recent results have shown that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors referred to as statins rapidly activate the protein kinase Akt/PKB in endothelial cells (ECs) and endothelial precursor cells (EPCs). This pathway is critical for cellular responses that contribute to angiogenesis and EC function including nitric oxide production, cellular survival and migration. METHODS: Here we tested whether statins control the translocation of recombinant and endogenous Akt to the plasma membrane of endothelial cells in a cholesterol-dependent manner. RESULTS: Low doses of statins rapidly induce the translocation of Akt to discrete sites in endothelial cell plasma membrane that colocalize with F-actin-positive, focal adhesion kinase (FAK)-negative lamellipodia and filopodia. This translocation event requires the lipid-binding, pleckstrin homology domain of Akt. Treatment with phosphoinositide 3-kinase (PI 3-kinase) inhibitors or the HMG-CoA reductase reaction product L-mevalonate blocks the translocation of Akt in response to statin stimulation. Furthermore, the ability of statins to promote Akt activation and translocation to the membrane is inhibited by cholesterol delivery to cells, but cholesterol loading had no effect on VEGF-induced Akt activation. CONCLUSIONS: These results suggest that statin activation of Akt signaling is mediated by the translocation of Akt to cholesterol-sensitive membrane structures within activated ECs. 相似文献
60.
Cold pain prolongs gastric emptying of liquid but not solid meal: an electrical impedance tomography (EIT) study 总被引:2,自引:0,他引:2
Nakae Y Kagaya M Takagi R Matsutani Y Horibe H Kondo T 《Journal of gastroenterology》2000,35(8):593-597
Stressful stimuli are reported to affect gastric emptying. However, methods for measuring gastric emptying are, in themselves,
stressful. Electrical impedance tomography (EIT) is a method for measuring gastric emptying noninvasively. We used EIT to
measure gastric emptying of liquid and solid meals to determine the effect of cold pain stress on gastric emptying. EIT (DAS-01P
APT system; University of Sheffield, UK) was carried out in six healthy women (age, 21.6 ± 0.4 [mean ± SD] years) who had
ingested a liquid (potage, 263 g; 139 kcal) or solid (beef patty, 205 g; 435 kcal) test meal. Cold pain stimuli consisted
of repeated immersions of the subject's non-dominant hand into ice water (4°C) for 1 min, with a 15-s recovery period between
immersions, for a total of 20 min. For the control stimulus, water at 37°C was used. The cold pain stimulus was applied immediately
after the ingestion of a test meal. All studies were carried out randomly in each subject at intervals of more than 1 week.
With cold pain, the half emptying time of the liquid meal was significantly greater than that with the control stimulus (47.6
± 26.1 min vs 28.1 ± 10.8 min, P < 0.05). For the solid meal, the half emptying time did not differ between stimuli (101.9 ± 44.8 min with cold pain vs 92.6
± 30.5 min with control stimulus). There were no significant differences in lag time between the liquid and solid meals. Cold
pain stress delayed gastric emptying of liquid but not solid meals.
Received: September 28, 1999 / Accepted: February 25, 2000 相似文献