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1.
The aim of this study was to establish whether the rate of fatty acid (FA) incorporation and its utilization by the isolated soleus muscle is modified under conditions of thyroid hormone deficit or excess. The rate of palmitic acid (PA) uptake, oxidation and incorporation into intramuscular lipids with increasing PA concentration (0.5–1.5 mM) in the incubation medium were determined. In hypothyroid rats intramuscular triacylglycerol (TG) synthesis was increased, while the rate of PA oxidation to CO2 and incorporation into mono- and diacylglycerols (MG/DG) and phospholipids (PL) remained unchanged. In rats with triiodothyronine (T3) excess the rate of all processes studied was enhanced, although the percentage incorporation of PA into different classes of intramuscular lipids was fairly constant and, independently of thyroid state and FA concentration in the medium, was 56–66% for TG, 9-14% for MG/DG and 24–32% for PL. Our results thus indicate that even short-term T3 excess accelerates the rate of FA uptake and metabolism in the oxidative soleus muscle, whereas in hypothyroid rats only intramuscular TG synthesis is affected.  相似文献   
2.
Summary The induction of mitotic recombination in theCDC8 locus was studied in a diploid strain heteroallelic forcdc8 mutations (cdc8-1/cdc8-3); mitotic reversion was studied in strainscdc8-1/cdc8-1 andcdc8-3/cdc8-3. Conversion and reversion did not occur in those cells blocked at the S stage of the cell cycle by exposure to a nonpermissive temperature. In stationary phase cells irradiated just prior to exposure to temperature stress, the induction of recombinants was rather low and the induction of revertants was minimal. Conversely, a significant induction ofcdc + occurred in logarithmic phase cells subjected to the same treatment. Irradiation of synchronously dividing cultures revealed that intragenic recombination occurs at all three stages of the cell cycle- G1, S and G2. It was also found that UV-induced gene reversion can occur during the S and G2 stages, but not during the G1 stage of the cell cycle.  相似文献   
3.
Summary Ten nuclear suppressors (nam mutations) of the mitochondrial oxi1-V25 ochre mutation are characterized. They restore to some extent the functional form of cytochrome oxidase, as judged by the results of growth tests, cytochrome spectra, cytochrome oxidase activities, and electrophoresis of the products of mitochondrial translation. The nam mutants can suppress some mit mutations mapping in four mitochondrial genes. They act on a number of chain-terminating mit mutations. When grown on glycerol medium some double mutants nam x-V25 show an increased sensitivity to paromomycin, while the growth of others is stimulated by the drug. The nam mutants are probably omnipotent suppressors resulting from mutations in nuclear gene(s) specifying mitoribosomal protein(s).  相似文献   
4.
Many unbalanced large copy number variants reviewed in the paper are associated with syndromic orofacial clefts, including a 1.6 Mb deletion on chromosome 3q29. The current report presents a new family with this recurrent deletion identified via whole-exome sequencing and confirmed by array comparative genomic hybridization. The proband exhibited a more severe clinical phenotype than his affected mother, comprising right-sided cleft lip/alveolus and cleft palate, advanced dental caries, heart defect, hypospadias, psychomotor, and speech delay, and an intellectual disability. Data analysis from the 3q29 registry revealed that the 3q29 deletion increases the risk of clefting by nearly 30-fold. No additional rare and pathogenic nucleotide variants were identified that could explain the clefting phenotype and observed intrafamilial phenotypic heterogeneity. These data suggest that the 3q29 deletion may be the primary risk factor for clefting, with additional genomic variants located outside the coding sequences, methylation changes, or environmental exposure serving as modifiers of this risk. Additional studies, including whole-genome sequencing or methylation analyses, should be performed to identify genetic factors underlying the phenotypic variation associated with the recurrent 3q29 deletion.  相似文献   
5.
Summary The -adrenergic agonist, clonidine, causes sedation in normal rats. The present study demonstrates that clonidine evokes strong locomotor stimulation in rats pretreated with 6-hydroxydopamine plus reserpine. Similar, but less intensive hyperactivity is observed in rats given clonidine after combined pretreatment with 6-hydroxydopamine plus p-chlorophenylalanine plus -methyl-p-tyrosine, or with reserpine plus low doses of yohimbine. The -adrenolytic drugs, phenoxybenzamine, phentolamine and aceperone, as well as high doses of yohimbine, antagonise the clonidine-induced locomotor stimulation; in contrast, the dopamine receptor blocking agents, pimozide and spiroperidol, exert no antagonistic effect. The results indicate that in the brain of normal animals, clonidine predominantly activates presynaptic -adrenoceptors on noradrenergic neurones and thereby induces sedation. After destruction of the noradrenergic fibres by 6-hydroxydopamine plus reserpine, activation of postsynaptic -adrenoceptors prevails so that hyperactivity results.This study was supported by Polish Academy of Sciences (10.4). Preliminary accounts were presented at the Pharmacology Meeting, Hannover, September 14–17, 1976 and at the 1 st Joint Symposium of Hungarian and Polish Pharmacological Societies, Zakopane, October, 13–15, 1976  相似文献   
6.
Zusammenfassung Es wurden 30 Fälle der Kniegelenksmeniskusverletzung im Kindesalter vorgestellt, die operativ behandelt waren. 20 der Behandelten wurden nach 1–12 Jahren nach dem operativen Eingriff nachuntersucht. Es wurden n die Ätiologie, der Verletzungsmechanismus und der klinische Befund besprochen. Die klinische und radiologische Nachuntersuchung ermöglichte die morphologische und funktionelle Auswertung des Kniegelenks nach der Meniskusverletzung.
Injury of the semilunar cartilages of the knee-joint in childhood
Summary In the paper, 30 patients at the age of 5 till 14 with injuries of the semilunar cartilages of the knee-joint, are presented. All the children were subjected to surgery, and 20 of them underwent same examinations performed in a delay of 1 to 12 years after they had been operated. Both etiology and the injury mechanism subjects are hadled together with the clinical pictures, specific to the age of the young patients. Basing on the clinical and X-ray examinations, the state of the morphological and functional condition of the knee of a child after semilunar cartilage had been removed, was considered and estimated.
  相似文献   
7.
The identification of a sub-endocardial infarction is of major interest in cardiology. This study evaluates the sensitivity of selected measures to the thickness of such an infarction. Synthetic ultrasonic data (long-axis view) of left ventricular models with inclusions were generated using Field II and meshes obtained from finite-element simulations, which also provided the reference for the estimates obtained from ultrasonic data. The displacements, the first and second component of the principal strain (ε1 and ε2), and several measures derived from these quantities were estimated. All estimates, except for the poorly estimated ε2, exhibited sensitivity to the presence and transmurality of the inclusion. The most sensitive was the gradient of the averaged transmural profiles of ε1, and ε1 averaged over the area corresponding to the transmural inclusion. The inflection point of the ε1 profile shifted toward the outer wall with increasing thickness of the non-transmural inclusion.  相似文献   
8.
9.
Blood samples of 50 patients diagnosed for paroxysmal nocturnal haemoglobinuria (PNH) were examined using FLAER screening test for the detection of PNH clone. The results were compared with routine testing using monoclonal antibodies detecting CD59 and CD66b antigens on neutrophils and CD59 on erythrocytes. Assay sensitivity (≥ 0.1%) and PNH clone size analysed using FLAER and anti-CD66b antibodies was fully consistent (R2 = 0.9991) and higher than with anti-CD59 antibodies. Preliminary results indicate that for diagnosis of PNH the FLAER based test is quick, reliable and cost-effective. It might seem that the conventional screening methods could therefore be abandoned. It was found however, that in some cases of abnormal granulocyte population, additional studies should be performed using multiparameter flow cytometry blood cell analysis.  相似文献   
10.
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