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971.
Enantiomerically pure hexahydroquinolinones of the structural type 9 were prepared by a variation of the Hantzsch synthesis in which an optically active acetoacetate served as a chiral auxiliary reagent. Determinations of the de and ee values are described. The absolute configurations of the optically pure products were characterized by single-crystal X-ray analysis. The antipodes 9a and 9b exhibited calcium antagonistic activities on smooth musculature; the (S)-(-)-enantiomer 9b was the more potent compound with regard to the EC50 values which differed by a factor of 100; the intrinsic activity of 9b was 1.2, compared with a value of 0.54 for 9a. On the other hand, R-(+)-9a exerted positive inotropic effects on electrically stimulated atria. The cause of these effects is discussed. 相似文献
972.
973.
The natural history of recurrent dislocation of the patella. Long-term results of conservative and operative treatment. 总被引:5,自引:0,他引:5
A Arnbj?rnsson N Egund O Rydling R Stockerup L Ryd 《The Journal of bone and joint surgery. British volume》1992,74(1):140-142
From 1970 to 1978, 29 patients had a unilateral operation for bilateral recurrent dislocation of the patella. We examined 21 of them at a mean of 14 years postoperatively. Eighteen of these patients had evidence of generalised joint laxity. Six of the operated knees and four of the unoperated knees still had recurrent dislocations. The operated knees were clinically worse, with a significantly higher incidence of osteoarthritis. We concluded that the operations used to treat recurrent dislocation of the patella may have had short-term benefits, but did not cure the patients in the long term. 相似文献
974.
975.
976.
977.
E V Ma?strakh O A Korobkina K F Korovin V I Severovostokova S N Tiglieva 《Kardiologiia》1988,28(1):41-44
A study of neurohumoral parameters in patients with essential hypertension and different hemodynamic types demonstrated different patterns of hormonal change in patients with hyperkinetic, eukinetic and hypokinetic hypertension. Elevated blood tri-iodothyronine and thyroxine, seen in patients with hyperkinetic hemodynamic type, and increased catecholamine excretion in patients with hypokinetic hemodynamics may be indicative of the pathogenetic significance of the hormones in question for the formation of respective variants of essential hypertension. 相似文献
978.
The electrochemical technique of differential pulse voltammetry (DPV) with micro-biosensors has been used for a number of years to monitor in vivo and in situ changes in the extracellular concentration of cerebral ascorbic acid, as well as that of the metabolites of dopamine (DA) and serotonin (5-HT). We have recently prepared a carbon fibre micro-electrode (mCFE) which specifically pretreated and coated with Nafion (a negatively charged polymer which repels acids such as 3,4-dihydroxyphenylacetic acid (DOPAC)) allows the direct selective detection of the oxidation of DA and 5-HT in nanomolar concentration in vitro and that of extracellular basal levels of cerebral 5-HT in vivo (peak B at +240 mV). We describe here a modified version of this micro-biosensor now called NA-CRO mCFE as its active tip (30 microns in diameter) is coated with a 50/50 (v:v) mixture of Nafion and dibenzo-18-crown-6 (Aldrich). In vitro this newly reported electrode shows insensitivity to acids (e.g., DOPAC) up to 100 microns and sensitivity to 0.5-1 nM DA. In vivo, in the striatum of anaesthetised rats, a basal oxidation peak at +80 mV (peak A, on average 0.6 nA in height), which corresponds to the oxidation potential of DA in vitro, is consistently detectable with the NA-CRO mCFE (corresponding to an estimated concentration of 1.5 nM). Experiments performed in vivo in anaesthetised rats implanted in the striatum with uncoated (normal) mCFE to measure extracellular DOPAC or with NA-CRO mCFE have been performed in order to analyse the chemical nature of peak A in vivo. It is concluded that the addition of the crown-ether compound to the Nafion coat improves the sensitivity of the micro-biosensor for DA in vitro and allows the detection of its basal extracellular levels in vivo. 相似文献
979.
Spastic paraparesis associated with portal-systemic venous shunting due to congenital hepatic fibrosis. 总被引:4,自引:0,他引:4
We report a case of progressive spastic paraparesis in a 45-year-old man with total portal-systemic shunting, which developed spontaneously due to congenital hepatic fibrosis. Cellular functions of the liver, except for an elevated blood ammonia level, were within normal limits, as is usual in congenital hepatic fibrosis. This case shows that spastic paraparesis following portal-systemic shunting may occur without liver failure. 相似文献
980.
We have examined the usefulness of ultrasound (US) in the detection of Achilles tendon (AT) xanthomata in heterozygous familial hypercholesterolemia. Our study is based on 30 adult subjects with heterozygous familial hypercholesterolemia (FH) (16 men, 14 women), 27 subjects with other non-familial forms of severe hypercholesterolemia (non-FH) with serum total cholesterol levels > or = 8 mmol/l (13 men and 14 women) and 31 subjects without marked hypercholesterolemia of the same age (control group; serum total cholesterol < 8 mmol/l) (15 men, 16 women). The three groups were comparable with respect to age, sex and body mass index. In the control group the mean sagittal thickness of AT was 4.5 mm (95% CI 3.2, 5.9 mm) and the mean coronal breadth of AT 11.0 (95% CI 9.0, 13.0 mm). Mean thickness of AT was 4.9 (range 4-7) mm in the non-FH group and 11.1 (5-16) mm in the FH group. The mean breadth of AT was in these groups 12.0 (10-17) mm and 19.2 (12-27) mm, respectively. Using the upper 95% confidence interval cut-off point in the control group as a criterion for normal AT thickness and breadth, 6 (22%) of non-FH and 29 (97%) of FH patients had increased AT thickness and 5 (19%) vs. 26 (87%) patients had increased AT breadth, respectively. The sensitivity of AT thickness for identifying FH was 0.97, specificity 0.78 and positive predictive value 0.83. The sensitivity of AT breadth in identifying FH was 0.87, specificity 0.81 and positive predictive value 0.84. None of the control subjects and none of the non-FH patients showed structural abnormalities of AT in the US, whereas 89% of FH-patients showed hypoechogenicity of AT. FH-score obtained by summing up the number of abnormal US findings gave a sensitivity of 0.93, a specificity of 0.96 and a positive predictive value of 0.96 for AT US in discriminating FH from non-FH. In conclusion, US examination of AT is a useful method in the detection of AT xanthomata and thus of help in the diagnosis of heterozygous FH. 相似文献