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991.
Identification of a Klebsiella pneumoniae strain associated with nosocomial urinary tract infection. 下载免费PDF全文
K S Kil R O Darouiche R A Hull M D Mansouri D M Musher 《Journal of clinical microbiology》1997,35(9):2370-2374
To differentiate between relapse of infection and reinfection of the urinary tract due to Klebsiella pneumoniae, 33 K. pneumoniae isolates collected from 20 patients with spinal cord injury (SCI) over 2 years were typed by genomic fingerprinting by repetitive-element PCR. Clinical isolates obtained from the same patients with recurrent episodes of urinary tract infection (UTI) revealed identical genomic fingerprints indicating relapse of UTI due to K. pneumoniae, despite appropriate antibiotic therapy. Seventeen isolates obtained from 8 of the 20 SCI patients shared a common genotype, termed RD6. Among non-SCI patients residing in other nursing units, the RD6 genotype was found in 5 of 10 patients with K. pneumoniae UTI but in only 1 of 20 patients with K. pneumoniae infection that did not involve the urinary tract, suggesting a strong association of this genotype with UTI. All RD6 isolates exhibited strong adherence (> or =50 adherent bacteria per cell) to HEp-2 cells, whereas other K. pneumoniae isolates generally did not adhere to or adhered very weakly to HEp-2 cells (< or =5 adherent bacteria per cell). Adherence was inhibited either by 4% D-mannose or by anti-type 1 fimbrial rabbit serum. These results suggest that the capacity of K. pneumoniae RD6 isolates to cause UTI may be mediated by its striking adherence to mammalian cells. 相似文献
992.
993.
Thirty-two castrated male crossbred growing pigs (average initial wt 26.9 kg) were used to determine the effect of a high level of dietary protein (37%) compared with a normal level of protein (15%) on enterobacteria and Campylobacter sp. inhabitation in the large intestine and on visceral organ hypertrophy and the interrelationships between these two factors. Pigs were kept in pairs (eight pens of two pigs/diet) and fed their respective diets and libitum. Eight pigs (two pens of two pigs fed each diet) were killed at wk 4, 8, 12 and 16 without fasting. Fecal samples were obtained every 2 wk from animals scheduled for necropsy at 16 wk, and colon contents were obtained from all pigs at necropsy; samples were enumerated individually for enterobacteria and Campylobacter sp. Weights of heart, lungs, liver, kidneys, perirenal fat and empty stomach, small intestine and large intestine were recorded at necropsy. Stomach, cecum and proximal colon were sectioned for histopathologic examination. Daily body weight gain was depressed by high dietary protein, but liver and kidneys were heavier in the high protein group than in controls at each time interval. Mild lymphoid hyperplasia of Peyer's patches in the small intestine in some pigs in both groups was indicative of antigenic stimulation but not of pathologic significance. There was no effect of diet on counts of enterobacteria or Campylobacter sp. in feces or colon contents during the 16-wk experiment. We conclude that the hypertrophic response of the tissues of growing pigs to high dietary protein is not the result of the presence of Campylobacter sp. or enterobacteria in the colon contents. 相似文献
994.
U Bergmann W K?nig W Gross-Weege B Schlüter M K?ller G Erbs F E Müller 《The Journal of trauma》1990,30(11):1372-1379
Thermal injury is known to induce dysregulation of the immune system; however, the precise mechanisms have to be clarified. We investigated the histamine release of basophil granulocytes from severely burned patients (n = 12) after stimulation with anti-IgE or the Ca-ionophore A 23187, respectively. The anti-IgE-induced basophil histamine release of all patients was reduced in comparison to healthy donors beginning at day one postburn (p.b.) (5.0 +/- 2.3% vs. 30.5 +/-3.4%), while the Ca-ionophore-induced release was not decreased before day two p.b. Basophils of patients who finally succumbed to their injuries showed poor responsiveness (to zero levels) over the total time. In contrast, the basophil releasability of surviving patients returned to nearly normal levels (fifth to seventh week p.b.). Already in the second week p.b. there was a significant difference in histamine release between survivors and nonsurvivors [e.g., days 6-9 p.b.: 23.7 +/- 4.0 vs. 6.9 +/- 2.7 (p less than 0.005) after Ca-ionophore stimulation]. The altered basophil histamine release was neither due to a diminished dose- or a delayed time-response to the stimuli nor due to differences in the basophil counts or the cellular histamine content. Our data indicate that the decrease of the basophil releasability, which may be secondary to altered signal transduction pathways in severely burned patients correlates with the clinical outcome. 相似文献
995.
G Marovi? 《Arhiv za higijenu rada i toksikologiju》1990,41(4):371-378
The paper is a survey of investigations into radioactive contamination of selected plant and animal species (bioindicators) which have the capacity for multiple accumulation of fission products. Literature data on the contamination of bioindicators are compared with special reference to the accumulation of 131I, 137Cs and 90Sr as a result of atmospheric nuclear experiments and the nuclear accident at Chernobyl. 相似文献
996.
The kinetics of inhaled methyl ethyl ketone (MEK) at a concentration of 200 ppm for four hours were studied in volunteers after swallowing ethanol at a dose of 0.8 g/kg. Ethanol was given either before or at the end of the exposure to MEK. The blood concentrations of MEK, 2-butanol, and 2,3-butanediol were monitored during and after the exposure. MEK concentrations in exhaled air and MEK and 2,3-butanediol concentrations in urine were also measured. Ethanol inhibited the primary oxidative metabolism of MEK and caused an increase in the blood concentrations of MEK and 2-butanol after ingestion. Ethanol ingestion, through higher blood MEK concentrations, also increased the elimination of MEK in the urine and exhaled air. Ethanol taken before exposure to MEK reduced the serum concentration of 2,3-butanediol initially but there was an increase about eight hours after the exposure. Urinary excretion of 2,3-butanediol followed the same pattern. Prior ingestion of ethanol thus seemed to interfere with the metabolism of 2,3-butanediol during and after exposure to MEK. 相似文献
997.
The author presents his experience of surgical treatment of 63 high congenital dislocations of the hip in schoolchildren. Osteotomy of the pelvis after Salter in combination with shortening osteotomy and open reduction of the hip has been used. Aseptic necrosis of the femoral head in the postoperative period has been revealed in almost 80% of the cases; the results were good during the first 10 years of observations in 28.5% and bad in 31% of the cases; after 10 and more years the percentage of good results fell to 18%. However, the patients gave a higher estimation of the treatment results as the period of clinical compensation of the operated joints lasted 10 to 12 pears, which made easier their contacts with schoolmates and family creation in future. 相似文献
998.
Three patients with interstitial cystitis diagnosed on the basis of clinical symptoms, classic endoscopic findings, and a typical histologic picture were treated with intravesical doxorubicin. All 3 patients showed remarkable improvement, as manifested by complete clearance of irritative bladder symptoms and healing of ulceration. Doxorubicin therefore may be the breakthrough drug for interstitial cystitis. 相似文献
999.
Two patients with a history of penile prosthesis removal presented for non-prosthetic treatment of their erectile dysfunction. The first patient had a penile implant for two years before it was removed and showed extensive cavernosal fibrosis. He did not respond to intracavernosal injection of vasoactive drugs. The second patient had the prosthesis for four weeks. He showed no evidence of cavernosal fibrosis and responded well to the intracavernous injection. He has been in an intracavernous autoinjection program for more than one year without complications. 相似文献
1000.
Two series of patients operated on with total hip replacements for arthrosis are reported. The same prosthesis and operative and cementing techniques were used in both series, except that in Series 2 a centralizing device consisting of four triangular fins passed over the tip was also used to improve the positioning of the femoral stem. It was found that the position of the tip was more central in Series 2. No drawbacks were associated with the use of the device. We concluded that the centralizing device facilitated the positioning of the femoral stem tip. 相似文献