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991.
A phase I study of SPI-077 (Stealth liposomal cisplatin) concurrent with radiation therapy for locally advanced head and neck cancer 总被引:2,自引:0,他引:2
Rosenthal DI Yom SS Liu L Machtay M Algazy K Weber RS Weinstein GS Chalian AA Mille LK Rockwell K Tonda M Schnipper E Hershock D 《Investigational new drugs》2002,20(3):343-349
Background: Liposomal cisplatinpreparations have two potential advantagesover the free drug when combined withradiation therapy (RT): 1) selective tumorlocalization, improving the therapeuticratio, and 2) prolonged half-life, allowingmore radiosensitization. We performed aPhase I study of Stealth® liposomalcisplatin (SPI-077) concurrent with RT forhead and neck squamous cell carcinoma(HNSCC).
Methods: Patients with StageIVa/b HNSCC were treated with SPI-077,given intravenously twice two weeks apart,concurrent with RT (60–72 Gy in 6–7 weeks).The SPI-077 dose was escalated in standardphase I design.
Results: Twenty patientsreceived 38 doses of SPI-077, escalatedfrom 20–200 mg/m2 in six dose levels.Two of these patients received one dosebecause of reversible Grade 3 livertoxicity or rash. Three patients had aGrade 1, and one had a Grade 2 infusionreaction. Four patients had transientlyelevated transaminases: Grade 1 (n = 1),Grade 2 (n = 1), and Grade 3 (n = 2). Grade 3neutropenia occurred in one patient. Therewas no ototoxicity, neurotoxicity, ornephrotoxicity. In-field radiation skin andmucosal toxicities did not appear to beintensified. Ten of 17 patients (59%)finishing treatment achieved initialcomplete response.
Conclusions: Systemic andin-field radiation toxicities of SPI-077were minimal. Infusion reactions wereminimized with a slower and more diluteinitial infusion. Further dose escalationwas stopped in the absence of dose-limitingtoxicity to address the reformulation ofthe liposomally bound cisplatin.Nonetheless, this study shows that highdoses of SPI-077 can be given safely. Thepotentially beneficial therapeutic ratiosuggests that liposomal radiosensitizerpreparations warrant furtherinvestigation. 相似文献
992.
Formoterol therapy for chronic obstructive pulmonary disease: a review of the literature 总被引:3,自引:0,他引:3
Numerous clinical trials have investigated the use of formoterol, a long-acting beta2-agonist, for the treatment of chronic obstructive pulmonary disease (COPD). Formoterol provides bronchodilation as rapidly as albuterol, yet its efficacy and duration of action are similar to those of salmeterol. It demonstrates better spirometric efficacy than either ipratropium or theophylline alone, and its efficacy improves when administered in combination with ipratropium. Formoterol improves patients' quality of life and has a good safety profile. It is better tolerated than theophylline and has a similar tolerability to albuterol, salmeterol, and ipratropium. In short, formoterol is a bronchodilator with rapid onset of action and prolonged duration of action with a favorable efficacy, safety, and tolerability profile when used in patients with COPD. It provides a valid therapeutic option in the pharmacologic treatment of this disease. 相似文献
993.
Pharmacodynamic effects and pharmacokinetics of a new HMG-CoA reductase inhibitor,rosuvastatin, after morning or evening administration in healthy volunteers 总被引:6,自引:0,他引:6 下载免费PDF全文
AIMS: To compare the lipid-regulating effects and steady-state pharmacokinetics of rosuvastatin, a new synthetic hydroxy methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, following repeated morning and evening administration in volunteers with fasting serum low-density lipoprotein cholesterol (LDL-C) concentrations < 4.14 mmol l-1. METHODS: In this open-label two-way crossover trial 24 healthy adult volunteers were randomized to receive rosuvastatin 10 mg orally each morning (07.00 h) or evening (18.00 h) for 14 days. After a 4 week washout period, volunteers received the alternative regimen for 14 days. Rosuvastatin was administered in the absence of food. RESULTS: Reductions from baseline in serum concentrations of LDL-C (-41.3%[morning]vs-44.2%[evening]), total cholesterol (-30.9%vs-31.8%), triglycerides (-17.1%vs-22.7%), and apolipoprotein B (-32.4%vs-35.3%) were similar following morning and evening administration. AUC(0,24 h) for plasma mevalonic acid (MVA), an in vivo marker of HMG-CoA reductase activity, decreased by -29.9% (morning) vs-32.6% (evening). Urinary excretion of MVA declined by -33.6% (morning) vs-29.2% (evening). The steady-state pharmacokinetics of rosuvastatin were very similar following the morning and evening dosing regimens. The Cmax values were 4.58 vs 4.54 ng ml-1, and AUC(0,24 h) values were 40.1 vs 42.7 ng ml-1 h, following morning and evening administration, respectively. There were no serious adverse events during the trial, and rosuvastatin was well tolerated after morning and evening administration. CONCLUSIONS: The pharmacodynamic effects and pharmacokinetics of rosuvastatin are not dependent on time of dosing. Morning or evening administration is equally effective in lowering LDL-C. 相似文献
994.
Mitchell LM Silveira M Mylne MJ Matthews K Dingwall WS 《Reproduction, fertility, and development》2002,14(3-4):207-213
The aim of this study was to determine whether previously observed seasonal differences in conceptus development in ewes are attributable to inherent differences in the oocyte and/or early embryo. Day 6 embryos were recovered from 50 ewes subjected to a standard oestrus synchronization, superovulation and laparoscopic artificial insemination protocol during October (peak breeding season) and April (transition to anoestrus). During the following October, 40 grade 1 and 2 embryos from each month, which had been cryopreserved at the late morula or unexpanded blastocyst stage, were thawed and transferred in singleton to synchronous recipients. Resulting pregnancies were monitored to term. For ewes receiving October- and April-produced embryos, overall mean +/- SEM liveweight at the time of embryo transfer was 72 +/- 0.7 kg, body condition score was 3.1 +/- 0.04 units, and the number of corpora lutea on the ovaries was 2.7 +/- 0.11 per ewe. Thirty-one and 27 ewes, respectively, became pregnant and their gestation lengths were 147 +/- 0.2 and 147 +/- 0.3 days. There was no effect of month of embryo production on peripheral ovine pregnancy-associated glycoprotein concentrations during pregnancy or on fetal and placental characteristics at term, but, for each month, male lambs were heavier than females and were associated with larger placentae. Lamb birthweight was positively correlated with placental weight (r2 = 0.474, P<0.001) and the total weight of cotyledonary tissue (r2 = 0.429, P<0.001), but not to the number of cotyledons. Results demonstrate close relationships between fetal and placental weights at term, and that seasonal effects on conceptus development in ewes do not arise from inherent differences in the oocyte and/or early embryo. 相似文献
995.
As research evidence for the effectiveness of community-based prevention has mounted, so has recognition of the gap between research and community practice. As a result, state and local governments are taking a more active role in building the capacity of community-based organizations to deliver evidence-based prevention interventions. Innovations are taking place in the establishment of technical assistance or support systems to influence the prevention and health education activities of community-based organizations. Several challenges for technical assistance systems are described: (1) setting prevention priorities and allocating limited technical assistance resources, (2) balancing capacity-building versus program dissemination efforts, (3) collaborating across categorical problem areas, (4) designing technical assistance initiatives with enough "dose strength" to have an effect, (5) balancing fidelity versus adaptation in program implementation, (6) building organizational cultures that support innovation, and (7) building local evaluative capacity versus generalizable evaluation findings. 相似文献
996.
Ward LR Maguire C Hampton MD de Pinna E Smith HR Little CL Gillespie IA O'Brien SJ Mitchell RT Sharp C Swann RA Doyle O Threlfall EJ 《Communicable disease and public health / PHLS》2002,5(4):301-304
In June 2001, as part of a microbiological study of bagged, ready-to-eat salad products, Salmonella enterica serotype Newport was isolated from a sample of pre-packed green salad distributed by a major supermarket retailer. The strain was characterised by phage typing, plasmid profile typing and pulsed-field gel electrophoresis. Other isolates of S. Newport from cases of human infection in England and Wales in the first six months of 2001 were similarly characterised. Of 60 strains from cases of human infection, 19 were found to be indistinguishable from that isolated from the salad product. This study highlights the benefits of an integrated approach to outbreak investigations, involving the various elements of the PHLS and the Food Standards Agency, and acknowledges the full co-operation of the retailer in ensuring the rapid withdrawal of the contaminated product. 相似文献
997.
Effects of non-steroidal anti-inflammatory drugs on cyclo-oxygenase and lipoxygenase activity in whole blood from aspirin-sensitive asthmatics vs healthy donors 总被引:2,自引:0,他引:2 下载免费PDF全文
Gray PA Warner TD Vojnovic I Del Soldato P Parikh A Scadding GK Mitchell JA 《British journal of pharmacology》2002,137(7):1031-1038
1. Cyclo-oxygenase (COX) and lipoxygenase (LO) share a common substrate, arachidonic acid. Aspirin and related drugs inhibit COX activity. In a subset of patients with asthma aspirin induces clinical symptoms associated with increased levels of certain LO products, a phenomenon known as aspirin-sensitive asthma. The pharmacological pathways regulating such responses are not known. 2. Here COX-1 and LO activity were measured respectively by the formation of thromboxane B(2) (TXB(2)) or leukotrienes (LT) C(4), D(4) and E(4) in whole blood stimulated with A23187. COX-2 activity was measured by the formation of prostaglandin E(2) (PGE(2)) in blood stimulated with lipopolysaccharide (LPS) for 18 h. 3. No differences in the levels of COX-1, COX-2 or LO products or the potency of drugs were found in blood from aspirin sensitive vs aspirin tolerant patients. Aspirin, indomethacin and nimesulide inhibited COX-1 activity, without altering LO activity. Indomethacin, nimesulide and the COX-2 selective inhibitor DFP [5,5-dimethyl-3-(2-isopropoxy)-4-(4-methanesulfonylphenyl)-2(5H)-furanone] inhibited COX-2 activity. NO-aspirin, like aspirin inhibited COX-1 activity in blood from both groups. However, NO-aspirin also reduced LO activity in the blood from both patient groups. Sodium salicylate was an ineffective inhibitor of COX-1, COX-2 or LO activity in blood from both aspirin-sensitive and tolerant patients. 4. Thus, when COX activity in the blood of aspirin-sensitive asthmatics is blocked there is no associated increase in LO products. Moreover, NO-aspirin, unlike other NSAIDs tested, inhibited LO activity in the blood from both aspirin sensitive and aspirin tolerant individuals. This suggests that NO-aspirin may be better tolerated than aspirin by aspirin-sensitive asthmatics. 相似文献
998.
Behavioural and biochemical evidence for interactions between Delta 9-tetrahydrocannabinol and nicotine 总被引:9,自引:0,他引:9 下载免费PDF全文
Valjent E Mitchell JM Besson MJ Caboche J Maldonado R 《British journal of pharmacology》2002,135(2):564-578
Behavioural and pharmacological effects of Delta9-tetrahydrocannabinol (THC) and nicotine are well known. However, the possible interactions between these two drugs of abuse remain unclear in spite of the current association of cannabis and tobacco in humans. The present study was designed to analyse the consequences of nicotine administration on THC-induced acute behavioural and biochemical responses, tolerance and physical dependence. Nicotine strongly facilitated hypothermia, antinociception and hypolocomotion induced by the acute administration of THC. Furthermore, the co-administration of sub-threshold doses of THC and nicotine produced an anxiolytic-like response in the light - dark box and in the open-field test as well as a significant conditioned place preference. Animals co-treated with nicotine and THC displayed an attenuation in THC tolerance and an enhancement in the somatic expression of cannabinoid antagonist-precipitated THC withdrawal. THC and nicotine administration induced c-Fos expression in several brain structures. Co-administration of both compounds enhanced c-Fos expression in the shell of the nucleus accumbens, central and basolateral nucleus of the amygdala, dorso-lateral bed nucleus of the stria terminalis, cingular and piriform cortex, and paraventricular nucleus of the hypothalamus. These results clearly demonstrate the existence of a functional interaction between THC and nicotine. The facilitation of THC-induced acute pharmacological and biochemical responses, tolerance and physical dependence by nicotine could play an important role in the development of addictive processes. 相似文献
999.
Cytokine-stimulated vascular smooth muscle cells release the colony-stimulating factors (CSFs) granulocyte macrophage-CSF and granulocyte-CSF. We have investigated the effects of a range of cytokines on the release of CSFs from human vascular smooth muscle cells stimulated with interleukin-1beta. Interleukin-4 suppressed granulocyte macrophage-CSF release but potentiated granulocyte-CSF release; interferon-gamma inhibited the release of both, whilst interleukin-5 had no effect. Both interleukin-10 and interleukin-13 inhibited granulocyte macrophage-CSF release but did not affect granulocyte-CSF release. The ability of individual cytokines to differentially modulate CSFs has profound consequences for the populations of leukocytes present at the site of inflammation. 相似文献
1000.
The mechanisms underlying myocardial dysfunction in sepsis remain poorly understood. The theoretical benefits of nitric oxide synthase (NOS) inhibition in reversing the haemodynamic changes that characterise septic shock have not been supported by clinical trials, some of which have demonstrated detrimental myocardial effects. We have therefore assessed the effects of endotoxaemia on NOS enzyme expression as well as a number of functional responses of myocardial tissue from rats. Atrial tissue expressed high levels of mRNA for inducible (i) NOS and released increased levels of nitrite after animals were treated with endotoxin. In parallel, the inotropic response stimulated by isoprenaline was reduced in atria from endotoxin-treated animals, an effect that was reversed when endogenous release of NO was maximised. Our results suggest that myocardial contractility is maintained by NO production and that inhibitors may compromise cardiac output; this may explain the deleterious effects of NOS inhibition on cardiac function in clinical trials. 相似文献