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排序方式: 共有7719条查询结果,搜索用时 15 毫秒
71.
David J. Stewart Robert S. Benjamin Mario Luna Lynn Feun Richard Caprioli William Seifert Ti Li Loo 《Cancer chemotherapy and pharmacology》1982,10(1):51-54
Summary Using X-ray fluorescence spectrometry, platinum concentrations were determined in autopsy tissue samples from 12 patients who had received cis-diamminedichloroplatinum (DDP) 20–120 mg/m2 up to 6 months antemortem. Tissue platinum concentrations were highest in liver (0.5–3.7 g/g wet weight), prostate (1.6–3.6 g/g), and kidney (0.4–2.9 g/g), somewhat lower in bladder, muscle, testicle, pancreas, and spleen, and lowest in bowel, adrenal, heart, lung, cerebrum, and cerebellum, Platinum concentrations in tumors were generally somewhat lower than the concentration in the organ in which the tumor was located, with the exception of intracerebral tumors. Different metastatic sites in the same patient had substantially different platinum concentrations and hepatic metasutases had the highest concentrations. Intra-arterial administration of drug may augment tissue concentrations of platinum. In a patient undergoing therapeutic abortion 4 days after treatment, the platinum concentration was 0.5 g/g in the placenta and 0.3 g/g in the fetus. The data suggest that for in vitro sensitivity testing, DDP concentrations of 7 g/ml should be used. 相似文献
72.
Laser Doppler anemometry (LDA) is a single-point technique which is unparalleled to detect accurately the local properties of the velocity field in a turbulent flow, such as that generated by a prosthetic heart valve (PHV). We propose a correlation between the structure of the flow field in three 19 mm bileaflet PHVs (Sorin Bicarbon, St. Jude Standard, St. Jude HP), investigated at peak systole (6 L/min cardiac output [CO]) with LDA, in kinematic and geometric similarity, and the global parameter of transvalvular pressure drop measured in both steady and pulsatile conditions. The pressure transducers of the same apparatus were used to characterize pressure drops at different flow rates whereas the steady-flow case was studied with a highly accurate tester built in our laboratory. The 2 St. Jude models rank according to their internal orifice diameter (ID) with the standard model (with a smaller ID) providing higher pressure drops for each flow rate. Sorin Bicarbon, due to its leaflet geometry, generates a more complex flow field with respect to the 2 St. Jude flat-leaflet models and shows improved hemodynamical behavior in pulsatile conditions with respect to the stationary case due to differences in pressure recovery. This study can provide insights into a PHV's local flow structure and global hemodynamical parameters. 相似文献
73.
Carlo Gambacorti-Passerini Massimo Zucchetti Domenico Russo Roberta Frapolli Magda Verga Silvia Bungaro Lucia Tornaghi Fabio Rossi Pietro Pioltelli Enrico Pogliani Daniele Alberti Gianmarco Corneo Maurizio D'Incalci 《Clinical cancer research》2003,9(2):625-632
PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule. 相似文献
74.
Enrico Zecca Daniele de Luca Simonetta Costa Marco Marras Pierluigi de Turris Costantino Romagnoli 《The journal of maternal-fetal & neonatal medicine》2006,19(9):569-574
OBJECTIVE: To investigate the effect of different delivery room strategies on survival, short term morbidity, and outcomes in extremely premature infants. METHODS: This retrospective cohort study included all preterm infants with a gestational age between 24 and 28 weeks who were born in 1992-1997 (period A; n = 161) and in 1998-2003 (period B; n = 163). In period A, elective intubation was performed. In period B, if spontaneous breathing was present, nasal continuous positive airway pressure (nCPAP) was applied. RESULTS: Survival rate and the number of never-intubated infants significantly increased in period B. No differences were found concerning short-term morbidity. Among major outcomes, the need for retinopathy of prematurity (ROP) surgery and the length of stay were significantly lower in period B. Subgroup analysis showed no significant differences from period A to period B in infants with gestational age 24-26 weeks. In the 27-28 weeks subgroup, the never-intubated infants rate increased from 2.8% to 21.3% and survival rate increased from 63% to 79%. A reduced need for ROP surgery and a shorter hospital stay were also observed. CONCLUSIONS: Changes in delivery room strategy tending to reduce mechanical ventilation in extremely premature infants are likely to benefit essentially infants of 27-28 weeks of gestation. Extension of such benefits to premature infants at the limit of viability requires further research. 相似文献
75.
Simona Soverini Giovanni Martinelli Gianantonio Rosti Simona Bassi Marilina Amabile Angela Poerio Barbara Giannini Elena Trabacchi Fausto Castagnetti Nicoletta Testoni Simona Luatti Antonio de Vivo Daniela Cilloni Barbara Izzo Milena Fava Elisabetta Abruzzese Daniele Alberti Fabrizio Pane Giuseppe Saglio Michele Baccarani 《Journal of clinical oncology》2005,23(18):4100-4109
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered. 相似文献
76.
Oleoylethanolamide inhibits food intake in free-feeding rats after oral administration. 总被引:3,自引:0,他引:3
Fariba Oveisi Silvana Gaetani Kevin Tai-Pang Eng Daniele Piomelli 《Pharmacological research》2004,49(5):461-466
Oleoylethanolamide (OEA) is an endogenous lipid that contributes in important ways to the peripheral regulation of food intake. When administered intraperitoneally, OEA is a potent satiety-inducing anorexiant in rats and mice [Nature 414 (2001) 209; Neuropsycopharmacology 28 (2003) 1311; Nature 425 (2003) 90]. In the present study, we show that oral administration of OEA in pH-sensitive enteric-coated capsules produces a profound and long-lasting inhibition of food intake in free-feeding rats. This effect is accompanied by a marked elevation in OEA levels in the small intestine, but not in brain or muscle. 相似文献
77.
Cerebrospinal anandamide levels are elevated in acute schizophrenia and are inversely correlated with psychotic symptoms. 总被引:7,自引:0,他引:7
Andrea Giuffrida F Markus Leweke Christoph W Gerth Daniela Schreiber Dagmar Koethe Johannes Faulhaber Joachim Klosterk?tter Daniele Piomelli 《Neuropsychopharmacology》2004,29(11):2108-2114
The endocannabinoids are a family of bioactive lipids that activate CB1 cannabinoid receptors in the brain and exert intense emotional and cognitive effects. Here, we have examined the role of endocannabinoid signaling in psychotic states by measuring levels of the endocannabinoid anandamide in cerebrospinal fluid (CSF) of acute paranoid-type schizophrenic patients. We found that CSF anandamide levels are eight-fold higher in antipsychotic-naive first-episode paranoid schizophrenics (n = 47) than healthy controls (n = 84), dementia patients (n = 13) or affective disorder patients (n = 22). Such an alteration is absent in schizophrenics treated with 'typical' antipsychotics (n = 37), which antagonize dopamine D2-like receptors, but not in those treated with 'atypical' antipsychotics (n = 34), which preferentially antagonize 5HT(2A) receptors. Furthermore, we found that, in nonmedicated acute schizophrenics, CSF anandamide is negatively correlated with psychotic symptoms (rS = -0.452, P = 0.001). The results suggest that anandamide elevation in acute paranoid schizophrenia may reflect a compensatory adaptation to the disease state. 相似文献
78.
79.
In vitro development of engineered muscle using a scaffold based on the pressure‐activated microsyringe (PAM) technique
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Daniele Cei Adriana Malena Carmelo de Maria Emanuele Loro Federica Sandri Giulia del Moro Sara Bettio Lodovica Vergani Giovanni Vozzi 《Journal of tissue engineering and regenerative medicine》2017,11(1):138-152
The development of new human skeletal muscle tissue is an alternative approach to the replacement of tissue after severe damage, for example in the case of traumatic injury, where surgical reconstruction is often needed following major loss of natural tissue. Treatment to date has involved the transfer of muscle tissue from other sites, resulting in a functional loss and volume deficiency of donor sites. Approaches that seek to eliminate these problems include the relatively new solution of skeletal muscle engineering. Here there are two main components to consider: (a) the cells with their regenerative potential; and (b) the polymeric structure onto which cells are seeded and where they must perform their activities. In this paper we describe well‐defined two‐ and three‐dimensional polymeric structures able to drive the myoblast process of adhesion, proliferation and differentiation. We examine a series of polymers and protein adhesions with which to functionalize the structures, and cell‐seeding methods, with a view to defining the optimal protocol for engineering skeletal muscle tissue. All polymer samples were tested for their mechanical and biological properties, to support the validity of our results in the real context of muscle tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
80.