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41.
BACKGROUND: Although the cytolytic, neurotoxic, and hemolytic actions of snake venoms are well known, the ability of airborne inhaled snake venom of the spitting cobra to induce asthma in snake handlers has not been reported. OBJECTIVE: To report the allergenicity of inhaled snake venom in a snake handler who developed increasing hypersensitivity to airborne venom, produced by spitting cobras during public demonstrations. METHODS: Serum samples were obtained from 2 handlers (our study patient and another snake handler who reported developing wheezing when handling spitting cobras), and desiccated venom was obtained from 9 species to which the handlers were exposed. Serum from an asymptomatic and nonatopic snake handler exposed to the same snake species was used as a control. Phosphate-buffered saline extracts were prepared from the desiccated venom, proteins in the venom extracts were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting was performed. Inhibition enzyme-linked immunosorbent assays (ELISAs) were performed to demonstrate cross-reactivity. RESULTS: The study patient had never been previously bitten by a cobra. Wheezing occurred rapidly on inhalational exposure and was reversed by inhalation of salbutamol. The patient had developed IgE antibodies to 9 different snake venoms on Western immunoblots, with major IgE binding proteins of 59 to 63 kDa and 8 to 15 kDa. The cross-reactive nature of the IgE epitopes in the venoms in the different species was also confirmed by 50% inhibition of IgE binding in an ELISA by preincubation with unrelated species. Life-threatening sensitivity of the patient was sustained after a long period of avoidance. CONCLUSIONS: We propose that aerosolized snake venom be considered a new potential source of allergens that may result in anaphylaxis on subsequent exposure. Further studies of the development of specific IgE sensitization following snakebites and the risks of such sensitization should be conducted on snake handlers, particularly those who demonstrate the spitting species. 相似文献
42.
Immunity to Influenza in Ferrets X. Intranasal Immunization of Ferrets with Inactivated Influenza A Virus Vaccines 下载免费PDF全文
The response of ferrets after intranasal inoculation of inactivated A/Hong Kong/68 (H3N2) influenza virus vaccines is reported. Normal ferrets given either saline vaccine in drops or freeze-dried vaccine in an aerosol intranasally did not produce detectable serum or nasal hemagglutination inhibiting antibody and were found to be completely susceptible to challenge infection with A/Hong Kong/68 virus. Intranasal saline vaccine did not produce an additive effect on the response of ferrets simultaneously given the same vaccine intramuscularly with adjuvant. Ferrets primed by previous infection with A/PR/8/34 (H0N1) influenza virus, however, responded to intranasal immunization with saline A/Hong Kong/68 virus vaccine and produced serum and nasal antibody. These animals were found to be partially resistant to challenge infection, in contrast to similar animals given saline vaccine intramuscularly which were completely resistant to challenge infection. Primed ferrets did not respond after immunization with the freeze-dried aerosol vaccine, but this may have been due to a failure of the aerosol to be inhaled satisfactorily. 相似文献
43.
Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women 总被引:4,自引:0,他引:4
Tworoger SS Yasui Y Vitiello MV Schwartz RS Ulrich CM Aiello EJ Irwin ML Bowen D Potter JD McTiernan A 《Sleep》2003,26(7):830-836
STUDY OBJECTIVES: To examine the effects of a moderate-intensity exercise or stretching intervention and changes in fitness, body mass index, or time spent outdoors on self-reported sleep quality and to examine the relationship between the amount and timing of exercise and sleep quality. DESIGN: A randomized intervention trial. SETTING: A cancer research center in Seattle, Washington. PARTICIPANTS: Postmenopausal, overweight or obese, sedentary women not taking hormone replacement therapy, aged 50 to 75 years, and recruited from the Seattle metropolitan area. INTERVENTIONS: A yearlong moderate-intensity exercise (n=87) and a low-intensity stretching (n=86) program. MEASUREMENTS AND RESULTS: Among morning exercisers, those who exercised at least 225 minutes per week had less trouble falling asleep (odds ratio [OR]: 0.3, P < or = .05) compared with those who exercised less than 180 minutes per week. However, among evening exercisers, those who exercised at least 225 minutes per week had more trouble falling asleep (OR: 3.3, P < or = .05) compared to those who exercised less than 180 minutes per week. Stretchers were less likely to use sleep medication (OR = 0.4, P < or = .05) and have trouble falling asleep (OR: 0.7, P < or = .10) during the intervention period compared with baseline. A greater than 10% versus a 1% or less increase in maximum O2 consumption over the year was associated with longer sleep duration (P < or = .05), less frequently falling asleep during quiet activities (P < or = .05), and less use of sleep medication (P < or = .05). Reductions in body mass index and increases in time spent outdoors had inconsistent effects on sleep quality. CONCLUSIONS: Both stretching and exercise interventions may improve sleep quality in sedentary, overweight, postmenopausal women. Increased fitness was associated with improvements in sleep. However, the effect of moderate-intensity exercise may depend on the amount of exercise and time of day it is performed. 相似文献
44.
Dohle GR; Ramos L; Pieters MH; Braat DD; Weber RF 《Human reproduction (Oxford, England)》1998,13(3):620-623
Male genital tract obstructions may result from infections, previous
inguinal and scrotal surgery (vasectomy) and congenital bilateral absence
of the vas deferens (CBAVD). Microsurgery can sometimes be successful in
treating the obstruction. In other cases and in cases of failed surgical
intervention, the patient can be treated by microsurgical or percutaneous
epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction
(TESE) and intracytoplasmic sperm injection (ICSI). We present the results
of 39 ICSI procedures for obstructive azoospermia in 24 couples. The
aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD
in nine and genital infections in four. Sperm retrieval was accomplished
via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was
only applied when PESA failed to produce enough spermatozoa for
simultaneous ICSI. In six patients, the ICSI procedure was performed with
cryopreserved spermatozoa after an initial PESA procedure. Fertilization
occurred in 47% of the metaphase II oocytes; embryo transfer was performed
in 92% of procedures and resulted in a clinical pregnancy in 13/39
procedures. Ongoing pregnancy was achieved in 10/39 procedures. One
pregnancy was terminated early after prenatal investigation showed a
cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine
pregnancies resulted in the live birth of 10 children, without any
congenital abnormalities. Epididymal and testicular retrieved spermatozoa
were successfully used for ICSI to treat obstructive azoospermia, and
resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI
procedures, a success rate of 25.6% per treatment cycle and of 27.7% per
embryo transfer.
相似文献
45.
L. T. Potter 《The Journal of physiology》1970,206(1):145-166
1. Segments of rat diaphragms were kept in choline-free media for 4 hr and were then exposed to a physiological concentration of [14C]-choline (30 μM) at 37° C. The synthesis, storage and subsequent release of [14C]acetylcholine by the muscles was assessed by isotopic- and bio-assays after isolation of the transmitter by paper electrophoresis.2. Replacement of endogenous acetylcholine (0·92 μ-mole/kg) with labelled acetylcholine proceeded slowly at rest, but rapidly during nerve stimulation. [14C]Acetylcholine accumulated most rapidly when hydrolysis of the released transmitter, and thus the re-use of endogenous choline, was prevented by an esterase inhibitor. Fully replaced stores were maintained during nerve stimulation by synthesis rates sufficient to replenish at least 35% of the store size in 5 min.3 In the presence of hemicholinium-3, which inhibits choline uptake, acetylcholine stores declined rapidly during stimulation, and residual synthesis was slight, indicating little intraneural choline. Net choline uptake into nerve terminals was estimated from the highest observed synthesis rate and from previous measurements of the number and size of terminals, as 3-6 p-mole/cm2 sec.4. Transmitter synthesis was localized in the region of end-plates, and was reduced to a few per cent of normal 6 weeks after phrenic nerve section. Release experiments suggested that at least half of the acetylcholine in phrenic nerves is in their terminals; from this content and the morphology of the terminals, the average concentration of transmitter in the whole endings would appear to be about 50 m-mole/l. Homogenization of the muscles freed choline acetyltransferase into solution, but left some [14C]acetylcholine associated with small particles, presumably synaptic vesicles.5. Resting transmitter release was about 0·013% of stores/sec. With 360 nerve impulses at 1-20/sec, release increased up to 0·43% of stores/sec, and amounted to 3·5-7 × 10-18 moles per end-plate per impulse. The release rate was unaffected by the doubling of store size which occurred with eserine, but the extra transmitter did help to maintain releasable stores during prolonged stimulation. Experiments with fractional store labelling indicated that newly synthesized acetylcholine was preferentially released.6. Preformed [3H]acetylcholine was not taken up and retained by muscle or nerve cells in the absence of an esterase inhibitor. With eserine present, labelled acetylcholine was taken up uniformly by muscle segments; when eserine was then removed, radioactive acetylcholine remained only near neuromuscular junctions. 相似文献
46.
Cloning and characterization of a protective outer membrane lipoprotein of Actinobacillus pleuropneumoniae serotype 5. 总被引:4,自引:0,他引:4 下载免费PDF全文
S Bunka C Christensen A A Potter P J Willson G F Gerlach 《Infection and immunity》1995,63(7):2797-2800
The gene encoding an outer membrane lipoprotein (omlA) of Actinobacillus pleuropneumoniae serotype 5 was cloned, and the protein was expressed in Escherichia coli. One open reading frame of 1,104 bp was detected that encoded a protein (OmlA) with a predicted molecular mass of 40 kDa. A comparison with the omlA gene and the corresponding protein of A. pleuropneumoniae serotype 1 (G.-F. Gerlach, C. Anderson, S. Klashinsky, A. Rossi-Kampos, A.A. Potter, and P.J. Wilson, Infect. Immun. 61:565-572, 1993) revealed that the nucleic acid sequences had an overall sequence identity of 62.9% and the deduced amino acid sequences showed a sequence agreement of 57.3%. Both proteins were antigenically distinct. In a Western blot (immunoblot) analysis using a specific antiserum against A. pleuropneumoniae serotype 5 OmlA, a homologous protein was detected in the reference strains of A. pleuropneumoniae serotypes 5A, 5B, and 10. Pigs immunized with this recombinant protein were protected from death in an aerosol challenge experiment with an A. pleuropneumoniae serotype 5 isolate. 相似文献
47.
48.
Immunity to influenza in ferrets. I. Response to live and killed virus 总被引:14,自引:0,他引:14
49.
C. F. Pauwels C. Van den Broecke J. M. Demeyer C. R. De Potter 《Virchows Archiv : an international journal of pathology》1998,432(3):299-300
This case report describes a chondroma of the bladder in a 63-year-old woman with clinical complaints of pain in the left
fossa iliaca. The lesion was a tumour with a lobulated growth pattern composed of chondrocytes embedded in a chondroid matrix.
Neither mitotic figures nor increased cellularity were present. Nuclei were inconspicuous. Immunohistochemical examination
showed reactivity for S100 and vimentin.
Received: 22 April 1997 / Accepted: 25 August 1997 相似文献
50.