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31.
Objective and design: Heparin has been shown to improve survival of surgical skin flaps. However, it is not known whether the protective effect of heparin is related to its anticoagulative or anti-inflammatory effects.Methods: Surgical flaps were raised in the dorsal skin of Sprague-Dawley rats. Neutrophil recruitment was determined by measuring the tissue content of myeloperoxidase (MPO) and clotting time was estimated by assessment of activated partial thromboplastin time (APTT) in plasma.Results: Administration of heparin (150 U/kg) significantly increased skin flap survival from 44% in vehicle-treated controls to 91%. This heparin treatment increased APTT by 4.5 fold. However, administration of 150 U/kg of heparin had no effect on skin flap neutrophil recruitment. In contrast, we found that the polysaccharide fucoidan reduced MPO and also improved skin flap survival.Conclusions: In conclusion, we demonstrate that protective effect of clinically relevant doses of heparin correlates with its ability to prolong clotting time and not to inhibition of neutrophil accumulation in the healing of skin flaps.Received 17 July 2003; accepted by N. Boughton-Smith 16 September 2003  相似文献   
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33.
Cholecystokinin (CCK) is a neuropeptide recently implicated in affective disorders. This study aimed at measuring the levels of different molecular forms of CCK and the binding characteristics of CCKB receptors in the rat brain after three weeks of treatment with four different antidepressants, imipramine, amitriptyline, desipramine, and citalopram (all at the dose of 10 mg/kg once per day i.p.). Chronic treatment with imipramine and desipramine had a significant immobility-reducing effect in the Porsolt‘s swim test. The effect of amitriptyline, albeit in the same direction, was not significant, and citalopram had no effect in this test. In the elevated plus-maze test of anxiety, all drugs tended to increase the number of open arm entries and the ratio open/total arm entries, but only the effects of imipramine were statistically significant. None of the treatments affected the total levels of CCK or the levels of CCK-8-sulphated, CCK-8-nonsulphated, CCK-5, or CCK-4 in the frontal cortex. There was no effect of the treatments on CCKB receptor binding in the frontal cortex, hippocampus, or striatum. Imipramine and amitriptyline, however, increased the affinity of CCKB receptor binding in the hypothalamus. Thus, no consistent effect of chronic antidepressant treatment on the CCK-ergic neurotransmission in the rats was found. Received: 4 June 1996 / Accepted: 26 August 1996  相似文献   
34.
Ten adult patients with homogeneous-linear deposition of IgA along the basement membrane zone have been studied. The direct immunofluorescence IgA pattern was stable, and there was no deposition of IgG or IgM. The clinical presentations were heterogeneous and resembled dermatitis herpetiformis (DH) (3 cases) or bullous pemphigoid (5 cases). Two patients had widespread gyrate blistering lesions of acute onset. Pruritus was constantly present. The course of the disease was chronic except for one patient who had a spontaneous remission after 5 years. The histology was indistinguishable from "classical" DH with granular IgA in dermal papillae. The patients studied in the present investigation did not show the high incidence of atrophic intestinal villi found in "classical" DH. Five of 9 cases carried the haplotype HLA-A1, B8, DR3. In spite of a close similarity between linear IgA dermatosis and DH, differences exist which indicate discrepancies in etiopathogenesis.  相似文献   
35.
Whole-body autoradiography in Sprague-Dawley rats injected i.v. with [14C]N-nitrosodiethanolamine ([14C]NDELA) showed a localization of tissue-bound radioactivity in the liver and the nasal olfactory mucosa. Microautoradiography of the nasal olfactory mucosa showed the highest labelling over the subepithelial glands (Bowman's glands) in the lamina propria mucosae. Experiments in vitro showed a capacity of the liver and the nasal mucosa to form 14CO2 from the [14C]NDELA. Most of the injected [14C]NDELA was recovered in the urine in a non-metabolized form. A small proportion of the dose was exhaled as 14CO2. The target tissues for the NDELA carcinogenesis in Sprague-Dawley rats are the liver and the nasal mucosa. Our results indicate that a bioactivation of the NDELA will take place in the nasal mucosa, as well as in the liver.  相似文献   
36.
Cholecystokinin (CCK) has been implicated in stress and anxiety disorders. We have studied the levels of different molecular forms of CCK and CCK receptor characteristics in rats kept for 1 h in individual cages and exposed to decapitation of conspecifics, and a control group which was decapitated immediately. Total CCK concentration was found to be increased in the hippocampus of stressed animals in the first experiment: this finding was not confirmed in further studies. No effect of stress was found on total CCK levels in the frontal cortex, hypothalamus, striatum, and septum. CCK-8-sulphated, CCK-8-nonsulphated, CCK-5, and CCK-4 were separated by HPLC and measured with two antibodies with different selectivity: no effect of stress was found on the levels of any of these molecular forms of CCK. Injection procedure and diazepam (5 mg/kg) administration had no effect on total CCK levels. Exposition of rats to the decapitation procedure increased [3H]-CCK-8 binding in the frontal and cerebral (whole - frontal) cortex. This effect could not be blocked by diazepam pretreatment. Injection procedure itself increased CCK receptor binding in the cerebral cortex, but the effect of this type of stress was smaller in magnitude. The upregulation of CCK receptors in stressed animals was due to the increased binding of radioligand on CCKB receptor subtype.  相似文献   
37.
Vitronectin, identical with serum-spreading factor and S-protein of complement, is a glycoprotein present in both plasma and tissue. It stimulates cell adhesion and spreading and affects the complement and coagulation pathways. Vitronectin immunoreactivity was recently found in conjunction with dermal and renal elastic fibres, in renal amyloid deposits in cases of AL- and AA-amyloidosis, and in sclerotic glomerular lesions. Skin specimens from lesions of patients with selected skin diseases were investigated with an avidin-biotin peroxidase technique using both monoclonal and polyclonal anti-vitronectin antibodies and an alkaline phosphatase anti-alkaline phosphatase technique using monoclonal anti-vitronectin antibodies. Vitronectin immunoreactivity was found in association with the abnormal elastic tissue in solar elastosis and pseudoxanthoma elasticum. It was also found in conjunction with dermal amyloid deposits in primary localized cutaneous amyloidosis and in Civatte bodies in cases of lichen ruber planus. In cases of erythropoietic protoporphyria and porphyria cutanea tarda, hyaline perivascular deposits also demonstrated positive vitronectin immunoreactivity. The presence of vitronectin immunoreactivity not only in normal and degenerated elastic fibres but also in various pathological tissue deposits suggests that vitronectin occurs both in elastic fibres and in different types of abnormal protein deposits.  相似文献   
38.
The results of 83 Salter's innominate osteotomies (i.o.) performed to correct congenital subluxation and dislocation of the hip joint in 76 patients were reviewed. The overall radiographic results were classified as excellent or good in 34 hips (41%) and as fair or failure in 49 hips (59%). The best results were obtained in subluxated hips, previously not treated or treated only with closed reduction, prior to i.o. in patients operated on before the age of 5 years. In that group of hips, excellent or good results were obtained in 18 of 20 hips (90%). The poorest results were obtained in hips with residual subluxation or dislocation after previous operation with a result of fair or failure obtained in 26 of 28 hips (93%).  相似文献   
39.
The transplacental pharmacokinetics of single teratogenic doses of etretinate and motretinide were compared with particular emphasis on distribution and concentrations in the exposed embryos of the free acid metabolite, etretin. The three aromatic retinoids were also tested for their direct inhibitory effect on chondrogenesis in the limb bud mesenchymal cell "micromass" culture assay. After a standard dose of 100 mg/kg administered on day 11 of gestation in NMRI mice, all three compounds were teratogenic, but they differed from each other in potency. Etretinate was most active as a teratogen, equalling the potency of our standard all-trans-retinoic acid; every exposed fetus was deformed with severe shortening of all limb bones as well as cleft palate. Etretin was less potent than etretinate, and motretinide was considerably less active as a teratogen than the other two. In the in vitro assay, only etretin suppressed chondrogenesis and this activity was equivalent to that of all-trans-retinoic acid (IC50 of 12 ng/ml). Both etretinate and motretinide (which contain an ethyl ester and ethylamide terminal group, respectively) were essentially inactive in vitro, demonstrating the fact that a free carboxylic group may be a requirement for the in vitro suppression of chondrogenesis. These differences between the results obtained in vivo and in vitro could be resolved by pharmacokinetic investigations using HPLC methods. Both etretinate and motretinide were metabolized in vivo to etretin, their likely common teratogenic metabolite. The high teratogenic potency of etretinate was probably the result of high concentrations as well as AUC values of its metabolite etretin in the embryo. On the other hand, the comparatively low teratogenicity of motretinide could be related to approximately 5 x lower embryonic peak levels as well as AUC values of etretin. A comparison of these results with those previously obtained for all-trans- and 13-cis-retinoic acids confirms the correlation between embryonic exposure and teratogenic potency in the mouse. Our results indicate that pharmacokinetic studies are essential for the interpretation of relative teratogenic potencies of retinoids as well as apparent differences between in vivo and in vitro teratogenesis. A free carboxyl group at the terminal end of the tetraene chain was necessary for high activity of the retinoids studied.  相似文献   
40.
We have studied two large unrelated Finnish families with myophosphorylase deficiency (McArdle's disease). In one, we identified a new nonsense mutation at codon 540 in exon 14 of the myophosphorylase gene, changing an encoded glutamic acid to a stop codon (E540X). The second family carried a splice-junction mutation at the 5' splice site of intron 14 (1844+G-->A), previously reported in one Caucasian patient and in a consanguineous Druze family. These data further enlarge the list of mutations associated with McArdle's disease and establish that McArdle's disease is genetically heterogeneous also within the Finnish population.  相似文献   
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