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31.
Dreyer G Medeiros Z Netto MJ Leal NC de Castro LG Piessens WF 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1999,93(4):413-417
The natural history of lymphatic disease in human filariasis remains unclear, but recurrent episodes of acute lymphangitis are believed to constitute a major risk factor for the development of chronic lymphoedema and elephantiasis. Prospective analysis of 600 patients referred to the filariasis clinic of the Centro de Pesquisas Aggeu Magalh?es/FIOCRUZ in Recife, Brazil, indicated that 2 distinct acute syndromes accompanied by lymphangitis occur in residents of this filariasis-endemic area. One syndrome, which we call acute filarial lymphangitis (AFL), is caused by the death of adult worms. It is relatively uncommon in untreated persons, usually is asymptomatic or has a mild clinical course, and rarely causes residual lymphoedema. The second syndrome, of acute dermatolymphangioadenitis (ADLA), is not caused by filarial worms per se, but probably results from secondary bacterial infections. ADLA is a common cause of chronic lymphoedema and elephantiasis in Recife as well as in other areas of Brazil where lymphatic filariasis is not present. The syndromes of AFL and ADLA can be readily distinguished from each other by simple clinical criteria. 相似文献
32.
Cation channel control of neurite morphology 总被引:4,自引:0,他引:4
Heng JE Zurakowski D Vorwerk CK Grosskreutz CL Dreyer EB 《Brain research. Developmental brain research》1999,113(1-2):67-73
The development of neuronal polarity and morphology is essential for a functioning nervous system. The present study was undertaken to explore whether blockade of specific channels alter neuronal morphology. Retinal ganglion cells were cultured in the presence of antagonists to NMDA, AMPA/kainate, L-, N-, P-, and Q-type voltage-dependent calcium channels (VDCCs). Five parameters were measured under these conditions: the number of neurites at the cell body, total neurite length, the length of the longest neurite, the number of branch points per neurite, and the diameter of the cell soma. Antagonists to NMDA and L-type VDCCs reduce the number of neurites at the cell body; antagonists to P- and Q-type VDCCs increase the number of neurites. Antagonists to the N-type VDCCs increase total neurite outgrowth, while antagonists to the NMDA and P-type channels reduce total neurite length. Antagonists to the NMDA and L-type channels increase the length of a single neurite, while decreasing the number of branch points; antagonists to the P- and Q-type VDCCs do essentially the opposite-increase the number of neurites, while decreasing the length of each. Blockade of one or more cation channels in developing retinal ganglion cells significantly perturbs neurite morphology. This study may help elucidate part of the role that cation channel signaling plays in neuritic development. 相似文献
33.
34.
Vorwerk CK Simon P Gorla M Katowitz W Zurakowski D Levin LA Dreyer EB 《Investigative ophthalmology & visual science》1999,40(3):813-816
PURPOSE: Muscarinic agents reduce intraocular pressure by enhancing aqueous outflow, probably by stimulating ciliary muscle contraction. However, pilocarpine is a well characterized neurotoxin and is widely used to generate animal seizure models. It was therefore investigated whether pilocarpine was also toxic to retinal ganglion cells. METHODS: Dissociated whole retinal preparations were prepared from postnatal day 16 to 19 rats. Retinal ganglion cells had been previously back-labeled with a fluorescent tracer. Retinal cells were incubated with pilocarpine, lithium, and inositol derivatives, and viability of the retrogradely labeled retinal ganglion cells was assayed after 24 hours. RESULTS: Pilocarpine was toxic to retinal ganglion cells in a dose-dependent fashion. This toxicity was potentiated by lithium and blocked by epi- and myo-inositol. CONCLUSIONS: Pilocarpine is toxic to retinal ganglion cells in a mixed culture assay. This toxicity appears to depend on the inositol pathway and is similar to its mode of action in other neurons. However, 0.4 mM pilocarpine (the lowest concentration that did not affect ganglion cell survival) is roughly 1000-fold higher than the vitreal concentration and 20-fold higher than the scleral concentration that can be obtained with topical administration of 2% pilocarpine in the rabbit eye. 相似文献
35.
Lanes SF Birmann BM Walker AM Sheffer AL Rosiello RA Lewis BE Dreyer NA 《PharmacoEconomics》1996,10(4):378-385
In order to characterise asthma management in a managed care setting, we identified 10,301 patients who were diagnosed with asthma between 1 January 1988 and 31 December 1991 at a group model health maintenance organisation in central Massachusetts, US. We obtained for these patients automated utilisation files containing data on medications, hospitalisations, emergency room visits, office visits, and estimated costs of these services. The medication dispensed to the greatest proportion of patients was beta 2 agonists either by inhalation (56%) or orally (21%). Theophylline was dispensed to 23% of the patients. Maintenance therapy was inhaled anti-inflammatory medication was uncommon, as inhaled corticosteroids (17%) and sodium cromoglycate (cromolyn sodium) [8%] were dispensed to fewer patients than other asthma medications. Among patients who had been hospitalised in the previous year, 36% were presently receiving inhaled corticosteroids, and among patients who used at least one beta 2 agonist metered-dose inhaler per month, 49% were presently receiving inhaled corticosteroids. Economic analyses showed that only 8% of the patients had either a hospital admission or an emergency room visit, but hospital costs among these patients accounted for 25% of the total costs of asthma care. In addition, the top 10% most expensive patients accounted for 42% of the total cost of asthma care. We conclude that a substantial proportion of patients at increased risk of a severe attack, by virtue of having a recent hospitalisation, do not receive maintenance anti-inflammatory therapy, and that hospitalisations among a relatively small proportion of asthma patients contribute significantly to the cost of asthma care. 相似文献
36.
Florian Guthmann Bernd Mayer Doris Koesling Walter R. Kukovetz Eycke Böhme 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(5):537-541
Summary Soluble guanylyl cyclase partially purified from bovine and human platelets was characterized with antibodies raised against synthetic peptides corresponding to different sequences of the 1- and 1-subunits of the bovine lung enzyme. On immunoblots, the platelet guanylyl cyclase was recognized by the four antisera used, with the exception of an antiserum against the C-terminus of the 1-subunit which did not react with the human platelet but with the bovine platelet 1-subunit. Furthermore the human platelet 1-subunit exhibited a slightly lower molecular mass than the bovine protein. The C-terminal antibodies precipitated native platelet and lung guanylyl cyclase activity. In contrast an antibody against a peptide out of the putative catalytic domain, which is highly conserved between all guanylyl cyclases sequenced so far, did not precipitate native guanylyl cyclase, although it recognized both subunits on immunoblots, suggesting that the respective amino acid sequence is located in an inner site of the protein.Abbreviations GCpep2
YGPEVWEDIKKEA (one letter code)
- GCpep3
SRKNTGTEETEQDEN
- GCpep5
VYKVETVGDKYMTVSGLP
- GCpep8
KKDVEEANANFLGKASGID
- TBS-T
Tris-buffered saline, containing 0.0501o Tween 20
Correspondence to E. Böhme at the above address 相似文献
37.
The role of cavitation during shock wave exposure was poorly understood until now. Cavitational activity produces severe damage to nearby surfaces due to multiple high-speed liquid jets resulting from bubble collapse. These jet impacts can be made visible by microscopy. For investigating the presence of cavitational processes by shock waves outside and even inside of targets, we have performed the following experiments. Natural gallstones and artificial targets were examined microscopically with regard to the effects of shock pulses. Scanning electron and light microscopical investigations revealed regularly typical and uniform microjet impacts within the fissures and split lines. Since these experiments are the continuation of high-speed films of 10,000 frames/s of shock wave actions on targets, it is most likely that the shock wave produces at first split lines through the stone. Then liquid occupies these cracks. But the following shock waves create within these liquid-filled fissures cavitation and, therefore, cause the disintegration of the targets. It now becomes understandable why biliary lithotripsy is less effective than renal lithotripsy: bile fluid is a high-viscous liquid and, therefore, hinders the disintegration of stones more than low-viscous urine. Intervals between the application of shock waves in biliary lithotripsy, therefore, should improve the treatment results. 相似文献
38.
Eduardo Bruera J Lynn Palmer Snezana Bosnjak Maria Antonieta Rico Jairo Moyano Catherine Sweeney Florian Strasser Jie Willey Mariela Bertolino Clarissa Mathias Odette Spruyt Michael J Fisch 《Journal of clinical oncology》2004,22(1):185-192
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain. 相似文献
39.
Urinary pharmacokinetics of betalains following consumption of red beet juice in healthy humans. 总被引:1,自引:0,他引:1
Thomas Frank Florian Conrad Stintzing Reinhold Carle Irmgard Bitsch Daniela Quaas Gabriele Strass Roland Bitsch Michael Netzel 《Pharmacological research》2005,52(4):290-297
The aim of the present pilot study was to characterise the renal elimination of betalains after consumption of red beet juice (RBJ). Six healthy, non-smoking female volunteers were given a single oral dose of either 500 mL of a commercial RBJ containing 362.7 mg of betalains and 500 mL of tap water, respectively, in a sequential manner. Urine was collected in intervals up to 24 h post-dose. Renal excretion of betalains was determined spectrophotometrically and quantified as betanin-equivalents. In addition, the identity of individual compounds was confirmed by HPLC coupled with diode-array detection and positive ion electrospray mass spectrometry, respectively. The amount (mean+/-S.D.) of intact betalains (betanin and isobetanin) recovered in urine was 1001+/-273 microg corresponding to 0.28+/-0.08% of the administered dose. Maximum excretion rates were observed after a median tmax,R of 3.0 h (range 2.5-8.0 h) amounting to 91.7+/-30.1 microg/h. The terminal elimination rate constant (lambdaz) and the corresponding half-life were 0.097+/-0.021 h(-1) and 7.43+/-1.47 h, respectively. Using the lambdaz estimates obtained the expected total betalain amount excreted in urine was 1228+/-291 microg. Based on the results obtained it is assumed that either the bioavailability of the betalains is low or that renal clearance is a minor route of systemic elimination for these compounds. The urinary excretion rates of unmetabolised betalains were fast and appeared to be monoexponential suggesting a one-compartment model. In order to get a more complete picture of the pharmacokinetics and health-promoting properties of red beet betalains, quantitative data on betalain bioavailability should include measurements of unchanged compounds and their corresponding metabolites in plasma, urine and bile. 相似文献
40.