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381.
We have evaluated a newly introduced immunoturbidimetric transferrin receptor assay (IdeA TfR-IT, Orion Diagnostica, Finland) in healthy subjects and in a study population consisting of patients with rheumatoid arthritis and juvenile chronic arthritis. The IdeA TfR-IT assay was found to provide reproducible results which were in good agreement with the ELISA assays from Orion Diagnostica (IDeA-ELISA, correlation R2=0.8, n=102) and R&D systems (Quantikine TfR ELISA assay, correlation R2=0.95, n=39). The analysis of the patient samples suggested that, on the basis of serum transferrin receptor and ferritin concentrations, in approximately one third of patients with rheumatoid arthritis anemia is due to the depletion of iron stores. Apparently, in all patients with rheumatoid arthritis iron deficiency must be considered as a potential cause of the anemia. Now, that assays which are suitable for automated analyzers have become available for the measurement of serum transferrin receptor, this analyte has the potential to become a part of the routine evaluation of iron status.  相似文献   
382.
Abstract: Adult male Wistar rats were administered acute toxic doses of lead (Pb), triethyl lead (TriEL) or tetraethyl lead (TEL) by gavage. The ability of striatal, hypothalamic and cortical synaptosomes to take up tritiated monoamines was assayed 24 hours later. Pb, TriEL as well as TEL increased dopamine (DA) uptake into striatal synaptosomes at least at some dose level. Pb increased, but TEL decreased 5-hydroxytryptamine(5-HT) uptake into hypothalamic synaptosomes, while TEL increased noradrenaline (NA) uptake into cortical synaptosomes. After a 3 week administration to initially 4 week old rats of even toxic doses of Pb in drinking water, monoamine uptake was not significantly affected. On the contrary, the neurotoxicity of TEL was cumulative in that a much lower dose decreased 5-HT uptake when divided over a 3 week period than acutely. In vitro TriEL inhibited DA uptake (IC50; 0.8 μM) into striatal and 5-HT uptake (5.0 μM) into hypothalamic synaptosomes but TEL and delta-aminolevulinic acid did not. The results suggest that dopaminergic and serotonergic neurones differ in their response to alkyl lead in vivo. The differences could be due to basic differences in the neurochemical behaviour of these two types of nerve endings.  相似文献   
383.
Four 3-phenyl-2-amino-trans-decalin isomers were synthesized in order to obtain derivatives of phenylethylamine with a rigid conformation between the phenyl ring and the amino function. The stereoisomers were tested as inhibitors of catecholamine uptake by rat brain synaptosomes, and their potency was compared with that of amphetamine. The most potent inhibitor of catecholamine uptake was the diaxial 2(a)-amino-3(a)-phenyl-trans-decalin, which was one-fourth to one-third as potent as (+/)-amphetamine. As a dopamine uptake inhibitor in the stiatum, this compound was competitive. The results differ from those obtained earlier with similar analogs with a norepinephrine moiety incorporated into the decalin structure, since a gauche derivative [2(a)-amino-3(e)-3,4-dihydroxyphenyl-3-trans-decalol] was then the most potent and over 20 times as potent as the diaxial anti derivative. It remains to be seen whether this indicates that the mode of binding of phenylethylamines is different from that of catecholamines.  相似文献   
384.
Voluntary alcohol intake has been reported to increase in rats after the repeated intracerebroventricular (ICV) administration of 1,2,3,4-tetrahydro-β-carboline (THBC) and some tetrahydroisoquinolines, although negative results have also been reported. THBC is a normal constituent in human plasma and platelets; 1-methyl-1,2,3,4-tetrahydro-β-carboline (1-Me-THBC), however, occurs in the blood after a person drinks alcohol. We have evaluated the effects of two doses of THBC and 1-Me-THBC on voluntary alcohol consumption in rats. ICV infusions were given with Alzet® minipumps for 14 days rather than giving repeated ICV injections. Stability of the drugs in the pump was verified using mass spectrometry. On each day the rats chose between water, alcohol (increasing concentrations from 3 to 30%) and an empty bottle. Alcohol intake increased by about 100%(p<0.05) during the last six days when 47 nmoles/hr of either THBC or 1-Me-THBC was infused. At the end of the experiment elevated blood concentrations of alcohol (0.02–0.78%) were found in rats belonging to the THBC or 1-Me-THBC groups and drinking 30% alcohol. The infusion of 0.47 nmoles/hr of either drug did not increase alcohol intake as compared to control.  相似文献   
385.
In a clinical double-blind study on 198 patients with a urinary tract infection, no differences were found between comparable groups treated with either sulfadiazine (SD) 1,000 MG/trimethoprim (TM) 320 mg or sulfamethoxazole (SM) 1,600 mg/trimethoprim 320 g daily for 2 weeks. The favorable results were obtained according to the bacteriological control in 85 and 79%, respectively. Also the incidence of side effects was the same (22 and 24%, resp.). The number of cases within which the treatment had to be discontinued did not differ percentually, either (6.6 and 8.4%, resp.). Based on the bacteriological sensitivity tests and the clinical trial, the authors conclude that TM can be combined with SD as well as with SM. Pharmacokinetic advantages, like a lower protein-binding and a lesser metabolism, may even make SD more preferable.  相似文献   
386.
Neurotransmitter regulation of anterior pituitary hormones   总被引:16,自引:0,他引:16  
  相似文献   
387.
Urinary catecholamines and cortisol were measured in healthy nonsmoking white collar workers (14 male and 15 female managers, 15 male and 14 female clerical workers), aged 30-50 years, during a one-hour period of laboratory-induced stress comprising five tests and a Type A interview, and during a subsequent period of rest in the laboratory. Values were compared with data obtained four months earlier from the same subjects during a normal day at work (4 values) and during a work-free day at home (4 values). No significant group differences were found during rest in the laboratory. However, during laboratory-induced stress, female managers had the highest norepinephrine values, which contributed to significantly (p less than 0.01) higher values in women than in men. Correlations between absolute measurements from laboratory and naturalistic conditions were generally positive and reached significance in most cases. Correlations between reactivity measurements in the laboratory and at work (change from rest to stress and from home to work, respectively) were generally low, whereas correlations between reactivity at different times of the day were relatively high. The data suggest that generalizability of neuroendocrine reactivity from laboratory stress to real-life stress is low. However, in agreement with earlier experimental findings, absolute levels of catecholamine and cortisol excretion were consistent over conditions and time.  相似文献   
388.
The obstetric implications of teenage pregnancy   总被引:4,自引:1,他引:3  
A retrospective review was performed on the obstetric outcome of teenage pregnancies delivered in 1 year in a tertiary centre. The results were compared with the rest of the obstetric population in the same hospital in the same year. The teenage mothers (n = 194) had increased incidence of sexually transmitted diseases (5.2 versus 1.0%, P < 0.05), and preterm labour (13.0 versus 7.0%, P < 0.01), but decreased incidence of gestational glucose intolerance (3.1 versus 11.4%, P < 0.001), when compared with the non-teenage mothers (n = 4914). There was no difference in the types of labour, while the incidence of Caesarean section was lower (4.1 versus 12.6%, P < 0.001) in the teenage mothers. Although the incidence of low birthweight was higher in the teenage mothers (13.5 versus 6.5%, P < 0.001), there was no significant difference in the mean birthweight, gestation at delivery, incidence of total preterm delivery, or perinatal mortality or morbidity. The results indicate that the major risk associated with teenage pregnancies is preterm labour, but the perinatal outcome is favourable. The good results accomplished in our centre could be attributed to the free and readily available prenatal care and the quality of support from the family or welfare agencies that are involved with the care of teenage mothers.   相似文献   
389.
ABSTRACT Cerebral magnetic fields preceding self-paced plantar flexions of the feet were studied with a SQUID gradiometer in 4 subjects. A slow magnetoencephalographic (MEG) shift was observed to begin as early as 1 sec before the movement. The shift changed its polarity between frontal and parietal areas. The MEG shifts preceding right and left foot movements were similar in shape, but their polarities differed at many recording locations. Simultaneous movements of both feet were preceded by shifts approximately equal to the sum of the shifts preceding the unilateral foot movements at the same recording location. The results suggest that the EEG and MEG shifts preceding foot movements are largely generated by tangential current sources on the mesial surface of the contralateral hemisphere around the motor representation area of the foot.  相似文献   
390.
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