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41.
The influence of a fraction obtained from Galeopsis ladanum L. on the central nervous system of rodents was examined. The results of these investigations show that the fraction impeded CNS activity. It is practically nontoxic and at a dose of 2000 mg/kg i.p. it does not have a soporific influence on mice. It reduces considerably the spontaneous locomotor activity of mice as well as the locomotor activity of mice stimulated by caffeine, but did not influence the locomotor activity induced by amphetamine. The extract did not exhibit a synergetic effect with barbiturates. The results suggest that the pharmacological activity of the extract resembled the activity of drugs which generally depress the CNS, being on the border between ataractic and sedative drugs. 相似文献
42.
Gerald C. Clark 《Archives of toxicology》1988,62(5):381-386
The acute toxicity of inhaled eugenol was assessed by exposure of three groups of five male and five female rats to a submicron aerosol of eugenol for 4 h followed by a 14-day observation period. A fourth group, also of five male and five female rats and exposed to air only under similar conditions, served as a control group for comparison. The three concentrations of eugenol to which the different groups were exposed were 2.58, 1.37 and 0.77 mg/l. The mass median aerodynamic diameters and geometric standard deviations of the aerosols were, respectively, 0.82 m (g 2.26), 0.88 m (g 2.05) and 0.9 m (g 1.87). Clinical signs observed during exposure consisted principally of moderately increased salivation and restlessness (indicative of irritation) and abnormal breathing patterns. The signs were graded, being less marked in animals exposed to the lower concentrations of eugenol. All three groups, exposed to high, medium and low levels of eugenol, lost weight overnight following exposure. Associated with the weight loss were marked reductions in food and water intake. The responses appeared to be largely independent of the concentration of eugenol inhaled, although there was some evidence of a graded effect on water intake. There was rapid recovery, with food and water consumption data comparable with control values throughout most of the remainder of the 14-day observation period. Also, by the end of the observation period, group mean body weights were comparable. Upon sacrifice and macroscopic examination of the animals, abnormalities were detected in the lungs only of a few animals: 3/10 control, 2/10 eugenol 2.58 mg/l, and 2/10 eugenol 0.77 mg/l. These consisted of dark red/red (raised) areas up to 4×4 mm. Such abnormalities are not uncommon in the lungs of laboratory maintained rats and their presence with equal incidence in control animals suggests that they are unlikely to be related to inhalation of eugenol. Lung weight to body weight ratio values for all groups were similar, providing no evidence of any persistent effect of eugenol on the lungs of the rats. Similarly, histopathological examination of the lung failed to reveal any treatment-related changes. A few incidental lesions present were considered spontaneous in origin and therefore of no toxicological importance. 相似文献
43.
Murakami R Obara H Momota T Tanaka A Nakamura H Mikawa K Iwai S 《Journal of anesthesia》1989,3(2):149-154
Morphological alterations in the lungs of rats deficient in either or both of vitamin E and essential fatty acids were investigated after exposure to hyperoxia for 48h. In rats deficient in both vitamin E and essential fatty acids, there was damage to type-2 alveolar cells observed as swollen mitochondria and bleb formation in the cytoplasm. None of these changes was found in rats deficient in only one of these substances. Hyperoxia in rats deficient in both substance also caused destruction of the capillary endothelial cells and edema in the interstitium. The lungs of rats deficient in only one of the substances showed some edema in the capillary endothelial cells, but not destruction, and less interstitial edema. These findings suggest that simultaneous deficiency in vitamin E and essential fatty acids facilitates lung damage in rats exposed to hyperoxia.(Murakami R, Obara H, Momota T et al.: The effect of hyperoxia on the lungs of rats deficient in essential fatty acids. J Anesth 3: 149–154, 1989) 相似文献
44.
毒性的产生应有物质基础,这种物质基础就是五味,中药的功效和毒性均来自五味。在五味中有毒药物的数量以辛、苦味为多,甘味最少,酸、咸味居中。 相似文献
45.
We previously reported that antibodies to squalene, an experimental vaccine adjuvant, are present in persons with symptoms consistent with Gulf War Syndrome (GWS) (P. B. Asa et al., Exp. Mol. Pathol 68, 196-197, 2000). The United States Department of Defense initiated the Anthrax Vaccine Immunization Program (AVIP) in 1997 to immunize 2.4 million military personnel. Because adverse reactions in vaccinated personnel were similar to symptoms of GWS, we tested AVIP participants for anti-squalene antibodies (ASA). In a pilot study, 6 of 6 vaccine recipients with GWS-like symptoms were positive for ASA. In a larger blinded study, only 32% (8/25) of AVIP personnel compared to 15.7% (3/19) of controls were positive (P > 0.05). Further analysis revealed that ASA were associated with specific lots of vaccine. The incidence of ASA in personnel in the blinded study receiving these lots was 47% (8/17) compared to an incidence of 0% (0/8; P < 0.025) of the AVIP participants receiving other lots of vaccine. Analysis of additional personnel revealed that in all but one case (19/20; 95%), ASA were restricted to personnel immunized with lots of vaccine known to contain squalene. Except for one symptomatic individual, positive clinical findings in 17 ASA-negative personnel were restricted to 4 individuals receiving vaccine from lots containing squalene. ASA were not present prior to vaccination in preimmunization sera available from 4 AVIP personnel. Three of these individuals became ASA positive after vaccination. These results suggest that the production of ASA in GWS patients is linked to the presence of squalene in certain lots of anthrax vaccine. 相似文献
46.
Gilbert TH Corley SM Teskey GC 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,146(3):336-344
This study addressed the anticonvulsant effects of phenobarbital, valproate, and ethosuximide in the amygdala of kindled guinea pigs to further validate this model for the screening of anticonvulsant drugs. Behavioral toxic effects were assessed at 30 min following drug administration using quantitative locomotor tests, as well as scores on a sedation and muscle relaxation rating index. The anticonvulsant efficacy of the drugs were evaluated from measurements of afterdischarge threshold (ADT), afterdischarge duration (ADD), and behavioral seizure severity (SS) during early and late phases of kindling acquisition, and in kindled guinea pigs. ADD and SS were also measured in response to both threshold and suprathreshold kindling stimulation. All drugs exerted slight to moderate sedative effects in guinea pigs on both the behavioral tests and rating index. We found that phenobarbital exhibited effective anticonvulsant properties in guinea pigs by consistently reducing ADD and SS in response to both threshold and suprathreshold kindling stimulation. Valproate exhibited effective anticonvulsant properties at threshold stimulation and less effective properties at suprathreshold stimulation. Lastly, we found that ethosuximide lacked effective anticonvulsant action at either threshold or suprathreshold kindling stimulation. Our results indicate that the guinea pig kindling model correctly predicted the actions of phenobarbital, valproate, and ethosuximide in the treatment of partial seizures. Guinea pig amygdala kindling appears to serve as a useful and valid model for partial epilepsy. 相似文献
47.
W. Robert Anderson 《Ultrastructural pathology》1990,14(3):221-232
The sequential stages of bronchopulmonary dysplasia occurring in 18 infants after intensive respiratory therapy supplemented by oxygen in high concentrations were studied by correlative light, scanning, and transmission electron microscopy. Infant survival ranged from 3 to 225 days. The earliest stage was an exudative reaction with a predominance of hyaline membranes. This merged with a subacute reparative response that was replaced by a chronic fibroproliferative stage in infants of longest survival; this stage was complicated by pulmonary fibrosis and emphysema. Correlative scanning and transmission electron microscopy demonstrated that type 2 pneumocytes contributed significantly to the reparative fibroproliferative response by organization of hyaline membranes and reepithelialization of damaged septal walls. 相似文献
48.
49.
YESIM TUNCOK SEBNEM APAYDIN SULE KALKAN MEHMET ATES & HULYA GUVEN 《International journal of experimental pathology》1996,77(5):207-212
The goal of this study was to compare the effects of glucagon and amrinone on mean arterial pressure (MAP) and heart rate, when used alone and in combination, in an anaesthetized rat model of verapamil toxicity. Rats were anaesthetized and the carotid artery was cannulated for MAP and heart rate measurements. Jugular and femoral veins were cannulated for drug administration. After verapamil infusion (15 mg/kg/h), control animals were given normal saline solution and the other groups received amrinone (0.1 or 0.2 mg/kg/min), glucagon (0.3 mg/kg bolus followed by 0.1 or 0.2 mg/kg/min infusion), glucagon plus amrinone (0.1 mg/kg/min and 0.1 mg/kg/min respectively) or glucagon plus amrinone (0.2 mg/kg/min and 0.1 mg/kg/min respectively). Glucagon (0.2 mg/kg/min) significantly increased MAP when compared to the control group ( P < 0.01). The combination of glucagon and amrinone did not produce a synergistic effect for the recovery of MAP. Furthermore, this combination masked the positive effects of glucagon (0.2 mg/kg/min) on MAP.Glucagon (0.2 mg/kg/min) increased the heart rates compared with those of the control group ( P < 0.05). Additionally, amrinone (0.1 mg/kg/min) plus glucagon (0.1 mg/kg/min) increased the heart rates ( P < 0.05). Finally, glucagon dose dependently recovered MAP. While amrinone depressed MAP in combination with glucagon, it did not alter the positive chronotropic effect of high dose glucagon. 相似文献
50.
Haseeb Khan Ahmad Saleh Al Deeb Khalaf Al Moutaery Mohammad Tariq 《Experimental and toxicologic pathology》2003,55(2-3):181-186
A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyskinetic syndrome. Male Wistar rats aged 3, 6 and 12 weeks received IDPN in the doses of 0, 200 and 400 mg/kg, intraperitoneally for 3 consecutive days. IDPN-induced dyskinesia was assessed using a behavioral testing battery on days 3, 4, 5, 6, 7, 14, 21 and 28. The rats were sacrificed on day 28; temporal bones were excised for vestibular histopathology and sera were collected for measuring the indices of oxidative stress (glutathione and conjugated dienes). IDPN in the dose of 200 mg/kg produced dyskinesia in 12 weeks old rats, but failed to do so in 3 and 6 weeks old rats. The high dose of IDPN (400 mg/kg) caused dyskinesia in all age groups, however, its onset and severity were age-dependent. Older rats showed an early onset and significantly high incidence of dyskinesia as compared to younger rats. The susceptibility of rats to IDPN-induced behavioral deficits was proportional to oxidative stress and degeneration of sensory hair cells in the crista ampullaris. 相似文献