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101.
Dragsted UB Gerstoft J Pedersen C Peters B Duran A Obel N Castagna A Cahn P Clumeck N Bruun JN Benetucci J Hill A Cassetti I Vernazza P Youle M Fox Z Lundgren JD;MaxCmin Trial Group 《The Journal of infectious diseases》2003,188(5):635-642
This trial assessed the rate of virological failure at 48 weeks in adult human immunodeficiency virus (HIV) type 1-infected patients assigned indinavir/ritonavir (Idv/Rtv; 800/100 mg 2 times daily) or saquinavir/ritonavir (Sqv/Rtv; 1000/100 mg 2 times daily) in an open-label, randomized (1:1), multicenter, phase 4 design. Three hundred six patients began the assigned treatment. At 48 weeks, virological failure was seen in 43 (27%) of 158 and 37 (25%) of 148 patients in the Idv/Rtv and Sqv/Rtv arms, respectively. The time to virological failure did not differ between study arms (P=.76). When switching from randomized treatment was counted as failure, this was seen in 78 of 158 patients in the Idv/Rtv arm, versus 51 of 148 patients in the Sqv/Rtv arm (P=.009). A switch from the randomized treatment occurred in 64 (41%) of 158 patients in the Idv/Rtv arm, versus 40 (27%) of 148 patients in the Sqv/Rtv arm (P=.013). Sixty-four percent of the switches occurred because of adverse events. A greater number of treatment-limiting adverse events were observed in the Idv/Rtv arm, relative to the Sqv/Rtv arm. In conclusion, Rtv-boosed Sqv and Idv were found to have comparable antiretroviral effects in the doses studied. 相似文献
102.
Maggiora M Bologna M Cerù MP Possati L Angelucci A Cimini A Miglietta A Bozzo F Margiotta C Muzio G Canuto RA 《International journal of cancer. Journal international du cancer》2004,112(6):909-919
Both n-6 and n-3 polyunsaturated fatty acids are dietary fats important for cell function, being involved in several physiologic and pathologic processes, such as tumorigenesis. Linoleic acid and conjugated linoleic acid, its geometrical and positional stereoisomer, were tested on several human tumor cell lines originating from different tissues and with different degrees of malignancy. This was to provide the widest possible view of the impact of dietary lipids on tumor development. While linoleic acid exerted different effects, ranging from inhibitory to neutral, even promoting growth, conjugated linoleic acid inhibited growth in all lines tested and was particularly effective against the more malignant cells, with the exception of mammary tumor cells, in which behavior was the opposite, the more malignant cell line being less affected. The inhibitory effect of conjugated linoleic acid on growth may be accompanied by different contributions from apoptosis and necrosis. The effects of conjugated linoleic acid on growth or death involved positive or negative variations in PPARs. The important observation is that a big increase of PPARalpha protein occurred in cells undergoing strong induction of apoptosis, whereas PPARbeta/delta protein decreased. Although PPARalpha and PPARbeta/delta seem to be correlated to execution of the apoptotic program, the modulation of PPARgamma appears to depend on the type of tumor cell, increasing as protein content, when inhibition of cell proliferation occurred. In conclusion, CLA may be regarded as a component of the diet that exerts antineoplastic activity and its effect may be antiproliferative or pro-apoptotic. 相似文献
103.
Casali PG Messina A Stacchiotti S Tamborini E Crippa F Gronchi A Orlandi R Ripamonti C Spreafico C Bertieri R Bertulli R Colecchia M Fumagalli E Greco A Grosso F Olmi P Pierotti MA Pilotti S 《Cancer》2004,101(9):2086-2097
BACKGROUND: To the authors' knowledge, no effective medical therapy currently is available for advanced chordoma. Imatinib mesylate is a tyrosine kinase inhibitor targeting platelet-derived growth factor receptor-beta (PDGFRB), BCR-ABL, and KIT. METHODS: Six patients with advanced chordoma were treated with imatinib mesylate at a dose of 800 mg daily. In all patients, the tumor was found to be positive for PDGFRB, and in four patients PDGFRB was shown to be phosphorylated/expressed. RESULTS: After a treatment period of > or = 1 year, overt tumor liquefaction was evident on computed tomography (CT) scan in the first patient. In previous months, a decrease in contrast enhancement on magnetic resonance imaging (MRI) and a decrease in glucose uptake on positron emission tomography (PET) were detected. Similar signs on MRI and PET were observed in subsequent patients, who had a shorter treatment period. One of these patients initially was removed from therapy and then was readmitted to therapy because of difficulties with regard to tumor response assessment; 1 month after the reinitiation of therapy, an overt decrease in tumor density was visible on CT scan in this patient. In four of five symptomatic patients, a subjective improvement was observed early in the course of treatment. The first patient died after 17 months, with a sizeable, mostly liquefied mass. Another patient died early, apparently of unrelated causes. The remaining patients were on therapy at the time of last follow-up. CONCLUSIONS: Imatinib mesylate has been found to have antitumor activity in patients with chordoma. This activity might be mediated by inactivation of PDGFRB. Tumor response manifests through patterns that are similar to those observed in patients with gastrointestinal stromal tumors who respond to molecular-targeted therapy, but evolves more slowly. The benefit to the patient entailed by this pattern of tumor response in chordoma needs to be elucidated, but may be limited in the presence of significant local disease. 相似文献
104.
Cozzi L Fogliata A Nicolini G Rancati T Bernier J 《Acta oncologica (Stockholm, Sweden)》2004,43(6):558-566
Since 2001, 50 breast cancer patients, for whom extensive lung/heart involvement was expected from the use of conventional tangential 2-field technique (2F) owing to complex anatomies, were irradiated using a 3-field conformal technique (3F). Dose plans were designed for both 3F and 2F and a dose volume histogram analysis on ipsilateral lung, heart, and target was conducted. The 3F technique allowed a significant reduction in ipsilateral lung irradiation: mean dose dropped from 16.0±3.8 (2F) to 12.0±2.7 Gy (3F) and V45Gy from 20.7±6.8 (2F) to 3.2±2.9% (3F). Similarly, in patients irradiated to the left breast, heart mean dose was reduced from 8.1 Gy (2F) to 6.8 Gy (3F) and D15% from 19.0 Gy to 14.0 Gy. All differences reached a high degree of significance. The target coverage was not clinically compromised since the slight reduction using 3F compared with 2F is limited to V95% while V90% difference, even if statistically significant, is small: 98.2±1.8% (3F) and 98.8±1.6 (2F). A preliminary report on clinical follow up is also included; with a mean follow up of 15.8 months, no pulmonary or cardiac complications were observed. 相似文献
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109.
Vimercati A Greco P Gentile A Ingravallo G Loverro G Selvaggi L 《Prenatal diagnosis》2003,23(1):44-47
OBJECTIVE: To demonstrate that thorough antenatal and postnatal investigations are helpful in any genetic syndrome. CASE REPORT: A woman without a specific risk had a finding of hyperechogenic foci at ultrasound. Karyotype on fetal blood was 47, XY+21 and extensive biochemical investigation revealed abnormal liver function. Given the suspicion of a coincidental hepatic compromise, targeted postmortem examination was performed, which showed hepatic fibrosis, megakaryocytes proliferation and invasion of sinusoid capillaries, all suggestive of a transient myeloproliferative disorder. CONCLUSION: When compared with chorionic villous and amniotic fluid sampling, fetal blood allows the collection of additional data, which may help in understanding the pathological process behind an apparently serendipitous association. 相似文献
110.
Aquilani R Iadarola P Boschi F Pistarini C Arcidiaco P Contardi A 《Archives of physical medicine and rehabilitation》2003,84(9):1258-1265
OBJECTIVE: To investigate whether levels of plasma tyrosine and tryptophan, precursors of brain catecholamine and serotonin neurotransmitters, respectively, and other essential amino acids (EAA) may return to normal in patients with severe traumatic brain injury (TBI) after 2 months in a hospital rehabilitation center. DESIGN: Peripheral plasma concentrations of tyrosine, tryptophan, and other EAAs in subjects with severe TBI, both at admission (44+/-11d postinjury) and at discharge from the center (110+/-15d after acute event) were compared with concentrations in control subjects. SETTING: Tertiary care rehabilitation setting in Italy. PARTICIPANTS: Ten men (26.6+/-12.6y) with TBI and 6 healthy subjects (controls) matched for age, sex, voluntary loss of body weight, and sedentary lifestyle. INTERVENTIONS: Not applicable. Main Outcome Measures: Concentrations of brain neurotransmitter precursor amino acids and of EAA. RESULTS: On admission, patients had lower plasma tyrosine, leucine, valine, methionine, and phenylalanine concentrations than did control subjects. The plasma concentrations of tryptophan were similar in the 2 groups. These amino acid abnormalities were still present at discharge. CONCLUSION: The levels of plasma tyrosine and many EAA in patients with TBI did not recover by discharge (110+/-15d) from rehabilitation. Plasma tryptophan concentrations were similar in patients and controls. 相似文献