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Exploratory activity in the open field and noradrenaline concentration in the neocortex and brain stem were investigated in intact rats (n = 10) and in the following groups of rats with early postnatal neurotoxic (6-hydroxydopamine) lesion of the catecholaminergic system: (i) rats with embryonal locus coeruleus grafts in the frontal neocortex (n = 5); (ii) rats with the same grafts in lateral ventricles (n = 4); (iii) a control group with intracortical hippocampal tissue grafts (n = 3); (iv) sham-operated rats (n = 3). Experiments were performed by four independent groups of investigators using a double-blind method. In sham-operated rats as well as in rats with hippocampal grafts, and with locus coeruleus grafts in the ventricles, both exploratory activity and noradrenaline content of the forebrain were significantly lowered. In the rats with intracortical locus coeruleus grafts the level of exploratory activity was much higher (almost as in intact controls). This improvement of exploratory behaviour correlated highly with increased noradrenaline concentration in the forebrain. In all animals with locus coeruleus in lateral ventricles a significant increase in noradrenaline level of the brain stem was present, but no change of exploratory behaviour was observed. The grafts with the 3-mm-thick slabs of the adjacent tissue were dissected from the brain and used for histological analysis. The presence of typical locus coeruleus cells was shown in neocortex of all animals which received the grafts of corresponding tissue. The data show the possibility of stable compensation of the forebrain noradrenaline level and exploratory behaviour by embryonic noradrenergic neurons grafted into the neocortex, but not into lateral ventricles.  相似文献   
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A simple method of synthesizing derivatives of 5-dimethylaminopyrano[3,2-c]quinolin-2-ones is proposed which involves obttaining 4-chloro- or 4-oxo-3-formylquinolines using compounds having an active methylene group. The pharmacological activity of the synthesized compounds is studied.  相似文献   
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Findings are presented of a comparative study investigating the family relationships and the emotional and gender development of children raised in lesbian mother families. A total of 30 lesbian mother families with 4-8 year old children created as a result of donor insemination (DI) were compared with 38 heterosexual families with a DI child and with 30 heterosexual families who had a naturally conceived child. A variety of assessment measures, including a standardized interview and questionnaires from the parents and psychological testing of the child were used to collect the data. The quality of the couples' relationships and the quality of the mother-child interaction did not differ between lesbian mother families and either of the heterosexual family groups. The quality of the interaction between the social mother and the child in lesbian families was superior to that between the father and the child in both groups of heterosexual families. Childrens' own perception of their parents was similar in all family types; the social mother in lesbian families was regarded by the child to be as much a 'parent' as the father in both types of heterosexual families. With regard to their emotional/behavioural development, boys and girls raised in lesbian mother families were well adjusted and their gender role development did not differ from that of children raised in heterosexual families. These results indicate that child and family development in lesbian mother families is similar to that of heterosexual families.   相似文献   
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Results from a comparative study investigating 38 donor insemination (DI) Dutch families with 4-8 year old children are presented. The aims of this study were to investigate parents' opinions on the issues of confidentiality and donor anonymity, to assess the emotional development of the children, and to examine in DI families the association between secrecy with regard to the use of a donor and the emotional adjustment of the children. The DI families were compared to families with a child conceived by in-vitro fertilization (IVF) and to families with a naturally conceived child. Secrecy appeared to be associated with DI and not with IVF: 74% of the DI parents intended not to inform the child about the way in which she/he was conceived, whereas none of the IVF parents intended to keep the secret. Only one set of DI parents and two sets of IVF parents had actually told the child. As to donor anonymity, a spread of opinions appeared among DI parents; 57% preferred an anonymous donor, 31% would have liked non- identifying information about the donor, 9% preferred the donor's identity to be registered and 3% remained unsure. Parents' major concern was to know more about the medical/genetic background of the donor. Mothers and fathers in the DI families differed in their opinions concerning the issues of confidentiality and donor anonymity: fathers, more often than mothers, were secretive with regard to the use of a donor and husbands, more often than their wives, were in favour of donor anonymity. With regard to the emotional development of the children, more emotional/behavioural problems were revealed among DI children than among children who were naturally conceived. No association was found between secrecy and the emotional/behavioural adjustment of the children.   相似文献   
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Transcutaneous immunization (TCI) is a new method for vaccine delivery that has been shown to induce immunity relevant to enteric disease vaccines. We evaluated the clinical safety and immunogenicity of a recombinant subunit vaccine against enterotoxigenic Escherichia coli (ETEC) delivered by TCI. Adult volunteers received patches containing the recombinant ETEC colonization factor CS6, either with heat-labile enterotoxin (LT) or patches containing CS6 alone. The vaccine was administered at 0, 1, and 3 months, and serum antibodies and antibody-secreting cells (ASCs) were assessed. Among the 26 volunteers that completed the trial, there were no responses to CS6 in the absence of LT. In the groups receiving both CS6 and LT, 68 and 53% were found to have serum anti-CS6 immunoglobulin G (IgG) and IgA, respectively; 37 and 42% had IgG and IgA anti-CS6 ASCs. All of the volunteers receiving LT had anti-LT IgG, and 90% had serum anti-LT IgA; 79 and 37% had anti-LT IgG and IgA ASCs. Delayed-type hypersensitivity (DTH), suggesting T-cell responses, was seen in 14 of 19 volunteers receiving LT and CS6; no DTH was seen in subjects receiving CS6 alone. This study demonstrated that protein antigens delivered by a simple patch could induce significant systemic immune responses but only in the presence of an adjuvant such as LT. The data suggest that an ETEC vaccine for travelers delivered by a patch may be a viable approach worthy of further evaluation.  相似文献   
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Comparative mapping of X-linked genes has progressed rapidly since Ohno's prediction that genes on the X chromosome should be conserved as a syntenic group in all mammals. Although several conserved blocks of homology between human and mouse have been discovered, rearrangements within the X chromosome have also been characterized. More recently, some exceptions to Ohno's law have been reported. We have used fluorescence in situ hybridization (FISH) to map five genes, Gla, G6pd, Hprt, Pgk1 and Xist, to two of the largest conserved segments of X material in five members of the genus Microtus (grey vole) and show that vole X chromosomes demonstrate greater homology to human than to mouse. Cytogenetic analysis indicates a relatively high frequency of rearrangement during vole evolution, although certain blocks of homology appear to be highly conserved in all species studied to date. On this basis we were able to predict the probable location of the rat X inactivation centre (Xic) based solely on high-resolution G-banding. Our prediction was then confirmed by mapping the rat Xist gene by FISH. The possible significance of conserving long-range chromosome structure in the vicinity of the Xic is discussed with respect to the mechanism of X inactivation.  相似文献   
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The aim of the study was to reveal general characteristics of the ligand-receptor interaction in the binding and displacement of radiolabeled ligands. The binding and displacement of DL-[3H]propranolol hydrochloride ([3H]propranolol) and L-[propyl-2,3, -3H]dihydroalprenolol ([3H]dihydroalprenolol), beta-adrenoceptor antagonists, were studied with isolated rat red blood cells, their membranes and ghosts. The binding of [3H]dihydroalprenolol and L-quinuclidinyl-[phenyl-4-3H]-benzylate ([3H]quinuclidinyl benzylate), a muscarinic acetylcholine receptor antagonist, was studied with cerebral cortex membranes. The ligand-receptor interaction corresponded to that for a model of two pools of receptors in the same effector system, with the binding of two ligand molecules to the receptors and was described by the following equation: b=[(B(m1)A(2))/(K(d1)(2)+A(2))]+[(B(m2)A(2))/(K(d2)(2)+A(2))]. The parameters of [3H]propranolol binding to beta-adrenoceptors were as follows: K(d1)=0.74 nM, K(d2)=14.40 nM, B(m1)=24 unit/cell, and B(m2)=263 unit/cell for native red blood cells from rats; K(d1)=0.70 nM, K(d2)=19.59 nM, B(m1)=9 fmol/mg protein, and B(m2)=39 fmol/mg protein for blood ghosts. The parameters of [3H]quinuclidinyl benzylate binding to muscarinic acetylcholine receptors of cerebral cortex membrane were as follows: K(d1)=0.43 nM, K(d2)=2.83 nM, B(m1)=712 fmol/mg, B(m2)=677 fmol/mg. The analysis of the equilibrium binding and displacement of [3H]propranolol and [3H]dihydroalprenolol at beta-adrenoceptors of membranes, ghosts and native red cells of rats, [3H]dihydroalprenolol at beta-adrenoceptors and [3H]quinuclidinyl benzylate at muscarinic acetylcholine receptors of synaptosomal membranes from rat cerebral cortex demonstrated that the receptors bound two ligand molecules each and consisted of two discrete pools of high- and low-affinity receptors. Similar results were obtained for the displacement of [3H]propranolol, [3H]dihydroalprenolol and [3H]quinuclidinyl benzylate by propranolol, dihydroalprenolol and quinuclidinyl benzylate.  相似文献   
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