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991.
Optimal indices for testing parkinsonian rigidity   总被引:1,自引:0,他引:1  
We assessed parkinsonian rigidity objectively at the wrist to determine the optimal angular velocity and displacement for detecting abnormality. The wrist was moved passively with a torque motor and the average work done for one complete cycle was computed. This objective rigidity score (ORS) was compared with a clinical rigidity score (CRS). ORS was more pronounced at faster movement velocities in parkinsonian patients, whereas in normal subjects there was only a modest increase in the score. Angular velocities of 140 to 190 degrees/second and displacements of +/- 25 to +/- 30 degrees were most sensitive for detecting parkinsonian rigidity and had good correlation with the CRS.  相似文献   
992.
Kidney histology of five infants who died during or immediately after treatment with adrenocorticotrophic hormone (ACTH) showed severe tubular and interstitial calcinosis. We therefore studied serum concentrations of calcium, inorganic phosphate, and parathormone, serum activities of alkaline phosphatase, and urinary excretion of calcium, inorganic phosphate, and cyclic adenosine monophosphate (cAMP) in 16 other children with infantile spasms before, during, and after 6 weeks of treatment with ACTH. During the treatment the following observations were made: hypocalcaemia developed in three infants; the mean daily urinary excretion of calcium in the group increased threefold and seven infants had hypercalciuria; the excretion of phosphate increased but its tubular reabsorption remained stable; and in most infants serum parathormone and urinary cAMP excretion increased, and in four infants they increased to supranormal concentrations. These biochemical changes were reversible in most infants. Radiographs suggested loss of bone mass by 3-4 weeks of treatment, with rapid recovery after treatment. We conclude that infants treated with ACTH for infantile spasms are at risk of suffering disturbance in calcium and phosphate homeostasis, which leads to nephrocalcinosis.  相似文献   
993.
Leukotriene B4 (LTB4) synthesis in rheumatoid synovitis was studied using peripheral and synovial fluid polymorphonuclear leukocytes (PMNs) and rheumatic synovial lining cells. No differences were found in LTB4 synthesis between peripheral PMNs from healthy volunteers and rheumatoid arthritis patients. When peripheral and synovial PMNs from the same RA patient were compared, arachidonic acid-induced LTB4 synthesis in synovial fluid PMNs was increased 1.7-7.2 fold, whereas the response to Ca ionophore A23187 stimulation was similar. This suggests 5-lipoxygenase stimulating factor(s) in inflamed joints. Rheumatic synovial lining cells in a primary cell culture produced small amounts of LTB4, the concentrations being less than 0.1 per cent of those of prostaglandin E2 (PGE2). PGE2 synthesis in synovial cells was increased when arachidonic acid or interleukin-1 was added to the culture, whereas LTB4 production remained unaltered. The present results suggest that in inflamed joints LTB4 originates mainly from PMNs whereas synovial lining cells are the source for PGE2.  相似文献   
994.
Serum and urinary beta-hexosaminidase as markers of heavy drinking   总被引:1,自引:0,他引:1  
Serum and urinary beta-hexosaminidase (SHEX and UHEX) were determined in 32 alcoholic men admitted to inpatient detoxification treatment for seven days, and in 27 teetotallers. On the admission SHEX was increased in 68.8% and UHEX in 81.3% and after seven days of abstinence the corresponding percentages were 37.5 (SHEX) and 71.9 (UHEX). During the treatment SHEX decreased significantly while UHEX did not. On the admission to the treatment UHEX correlated positively with SHEX (r = 0.54; P less than 0.01). The results suggest that UHEX may be a more sensitive marker of heavy drinking than SHEX. Furthermore UHEX stays longer elevated than SHEX.  相似文献   
995.
996.
As a part of a series of studies to develop prodrug derivatives of pilocarpine, the O,O'-succinyl (dibenzyl), O,O-adipoyl (dibenzyl), O,O-fumaryl (dibenzyl), and O,O-terephthaloyl (dibenzyl) bispilocarpate fumarates were synthesized as a new class of pilocarpine prodrugs. The compounds were prepared from pilocarpic acid benzyl monoester by coupling two pilocarpic acid benzyl monoesters together with spacer chains by usual esterification methods. Liquid chromatography, thermospray liquid chromatography-mass spectrometry, high-resolution mass spectrometry, and NMR spectroscopy were applied to the identification and the purity evaluation of the synthetic products.  相似文献   
997.
The effect of peroral administration of xylitol on the absorption of iron and the activities of xanthine oxidase (EC 1.2.3.2) and ferroxidase in rat duodenal wall was studied. Adult male rats were given the basal diet containing 200 g xylitol/kg or the same diet containing no added carbohydrates for 8 weeks. Both feeding groups comprised twelve animals. Xylitol significantly increased serum and liver Fe concentrations with a concomitant, significant increase in the duodenal xanthine oxidase activities, but caused a marginal increase in the duodenal ferroxidase activities. In vitro, sugar alcohols reduced the binding rate of Fe to transferrin. The xylitol-induced increase of Fe absorption may involve the following mechanism: the high intraluminal xylitol concentration of the xylitol-fed rats keeps Fe in the form of a soluble complex for a prolonged period of time, due to the slow absorption of xylitol. The polyol-Fe complex in turn induces xanthine oxidase and ferroxidase formation.  相似文献   
998.
Fresh frozen plasma reduces thrombin formation in newborn infants   总被引:2,自引:0,他引:2  
Summary.  Background : Newborn infants undergoing intensive care are at risk of bleeding and thrombotic complications. Fresh frozen plasma (FFP) is used in hope of preventing these complications, despite poorly defined effects on the coagulation system and lack of proven clinical efficacy. Objectives and methods : We prospectively evaluated coagulopathy and the effect of standardized amount of FFP transfusion (10 mL kg−1 + 4 mL in 2 h) on various coagulation markers in 33 newborn infants during the first 24 h of intensive care. Results : Increased levels of prothrombin fragment F1+2, thrombin–antithrombin complexes (TAT), and d -dimer were found prior to the transfusion in 97%, 81%, and 100% of the patients, respectively. FFP transfusion was associated with a decrease in F1+2 level in 26/32 (81%) of the patients. The extent of F1+2 decrease correlated with the pretransfusion F1+2 level ( R  = 0.65, P  < 0.0001). The patient series was divided into two groups according to increasing pretransfusional F1+2 level: Group 1 (preFFP F1+2 ≥ 2.35 n m , n  = 16), Group 2 (F1+2 <2.35 n m , n  = 16). In Group 1, F1+2 decreased on average 1.58 n m ( P  < 0.01) from the baseline during FFP transfusion but no significant change in the level of F1+2 during the transfusion was observed in Group 2. Pretransfusional levels of individual factors or prothrombin time (PT) did not correlate with the FFP-associated decrease in F1+2 level. Conclusions : In the patients with the highest pretransfusional thrombin formation, FFP had an acute thrombin-reducing effect. Pretransfusion thrombin generation markers, rather than PT or individual pro- and anticoagulants, may be helpful in identifying the patient who will have measurable coagulational effects induced by FFP.  相似文献   
999.
Sclerotherapy has gained increasing popularity during the last few years as a treatment for hydrocele. Little is known of the natural course of intrascrotal changes, however, nor of their timetable after therapy. In the present trial scrotal ultrasonography was performed before the sclerotherapy and during the follow-up examination in the case of 70 symptomatic consecutive outpatients ranging in age from 19 to 85 years (mean, 58 years) with 71 hydroceles treated by ethanolamine oleate sclerotherapy. Posttreatment sonographic findings typically included heterogeneously echogenic extratesticular masses, cystic areas with peritesticular hyperechoic lines, and a thickened scrotal wall. All the lesions showed improvement. Sonography proved to be useful for differentiating hydroceles from spermatoceles and for evaluating the need for a renewed treatment during follow-up. Ethanolamine oleate was effective as a sclerosant, as 86% of cases were cured or significantly improved. Complications were mild and uncommon, and no intratesticular or epididymal changes were observed. Ethanolamine oleate sclerotherapy can be recommended as a treatment of choice for hydrocele.  相似文献   
1000.
Simultaneous auditory processing between the hemispheres was studied with a whole-head magnetometer in 13 abstinent chronic alcoholics and 10 healthy control subjects. Auditory stimuli were presented monaurally with interstimulus intervals of 0.5 and 2.5 sec in different blocks. The N100m response, which contributes to stimulus detection, was significantly accelerated in the hemisphere ipsilateral to the ear stimulated in abstinent alcoholics. The MMNm response reflecting automatic stimulus-change detection peaked earlier in alcoholics, and the ipsilateral N100m latency correlated significantly with the abstinence duration. These results suggest that auditory processing is accelerated in the auditory cortex ipsilateral to the stimulated ear in chronic abstinent alcoholics and that the accelerated processing is at least partly reversible. This may be caused by the hyperexcitation in the brain related to the ethanol withdrawal.  相似文献   
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