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81.
Sixty-two patients with pituitary dwarfism were treated with three different preparations of methionyl hGH (m-hGH) for 3 to 14 months. They were given 0.5 IU/kg/week intramuscularly. The growth rate during treatment with the three different preparations was the same for each and increased from 3.5 +/- 0.9 to 8.2 +/- 1.7 cm/year. A high incidence of hGH antibody formation was observed following the treatment, but the titer of antibody was decreased according to the purity of m-hGH preparations. At the end of 12 month treatment with a highly purified preparation (Somatonorm III), 76.2% of the patients had hGH antibody. However, the presence of antibodies did not affect the growth rate except in one patient. No clinical or laboratory side-effects were observed following the treatment with m-hGH. Thus, m-hGH was considered to be useful for the treatment of GH deficient children.  相似文献   
82.
mAb and polyclonal antibodies against human IL-6R were prepared by using a murine transfectant cell line expressing the human IL-6R and a synthetic oligopeptide made on the basis of the deduced amino acid sequence as immunogens. Immunoprecipitation of radiolabeled IL-6R with these antibodies showed that the Mr of a mature IL-6R was 80 kDa and its value was reduced to 50K after treatment with O- and N-glycanase and neuraminidase, indicating that IL-6R is a glycoprotein. Two mAb recognizing different epitopes were prepared. One, PM1 inhibited the binding of 125I-IL-6 to the receptor and blocked the IL-6-dependent growth of a T lymphoma line, KT3. PM1 could not bind to IL-6R when it was saturated with IL-6, indicating that this antibody recognizes the IL-6 binding or the adjacent site on IL-6R. The other, MT18 was not inhibited by IL-6 for its recognition of IL-6R, therefore, this could be used for cytofluorometric staining of normal cells. Nonstimulated B cells expressed undetectable amount of IL-6R regardless of the expression of surface IgD. However, after the stimulation with PWM, IL-6R was observed on IgD- B cells with a relatively large size, but subtly on IgD- small B cells and not on IgD+ B cells, fitting the function of IL-6 which acts on activated B cells to induce Ig production. In contrast, IL-6R was detected on non-stimulated CD4+/CD8- and CD4-/CD8+ T cells. The level of IL-6R on both T cell subpopulations was not significantly changed after stimulation with phytohemagglutinin.  相似文献   
83.
The type strain (ATCC 27335) and 18 human oral isolates of Streptococcus intermedius and some other related streptococcal species were tested for chondroitin sulfate C-depolymerizing activity employing a modified screening plate method of Smith and Willett. As the results, S. intermedius strains except for ATCC 31412 strain were found to possess this activity. Propionibacterium acnes ATCC 11828 used as a positive control strain demonstrated strong activity, whereas S. intermedius strains showed only slightly detectable activity. This finding might be interesting in view of the classification of this species as well as its pathogenicity.  相似文献   
84.
BACKGROUND AND AIM: Helicobacter pylori is known to be a major pathogenic factor in the development of gastritis, peptic ulcer disease and gastric cancer. Recently, chicken egg yolk immunoglobulin Y (IgY) has been recognized as an inexpensive antibody source for passive immunization against gastrointestinal infections. The present study was designed to investigate the effect of anti-urease IgY on H. pylori infection in Mongolian gerbils. METHODS: H. pylori-infected Mongolian gerbils were administered a diet containing anti-urease IgY, with or without famotidine (F). After 10 weeks, bacterial culture and measurement of the gastric mucosal myeloperoxidase (MPO) activity were performed. In a second experiment, another group of gerbils was started on a diet containing F + IgY a week prior to H. pylori inoculation. After 9 weeks, these animals were examined. RESULTS: In the H. pylori-infected gerbils, there were no significant differences in the level of H. pylori colonization among the different dietary and control groups. However, the MPO activity was significantly decreased in the H. pylori group administered the F + IgY diet compared with that in the H. pylori group administered the IgY, F, or control diet. Furthermore, in the gerbils administered the F + IgY diet prior to the bacterial inoculation, inhibition of H. pylori colonization and suppression of the elevated gastric mucosal MPO activity were observed. CONCLUSIONS: Oral administration of urease-specific IgY not only inhibited H. pylori disease activity in H. pylori-infected gerbils, but also prevented H. pylori colonization in those not yet infected. These encouraging results may pave the way for a novel therapeutic and prophylactic approach in the management of H. pylori-associated gastroduodenal disease.  相似文献   
85.
The molecular mechanisms controlling the differentiation of neural progenitors into distinct subtypes of neurons during neocortical development are unknown. Here, we report that Fezl is required for the specification of corticospinal motor neurons and other subcerebral projection neurons, which are absent from Fezl null mutant neocortex. There is neither an increase in cell death in Fezl(-/-) cortex nor abnormalities in migration, indicating that the absence of subcerebral projection neurons is due to a failure in fate specification. In striking contrast, other neuronal populations in the same and other cortical layers are born normally. Overexpression of Fezl results in excess production of subcerebral projection neurons and arrested migration of these neurons in the germinal zone. These data indicate that Fezl plays a central role in the specification of corticospinal motor neurons and other subcerebral projection neurons, controlling early decisions regarding lineage-specific differentiation from neural progenitors.  相似文献   
86.
In teleosts and amphibians, the proneuronal domains, which give rise to primary-motor, primary-inter and Rohon-Beard (RB) neurons, are established at the beginning of neurogenesis as three longitudinal stripes along the anteroposterior axis in the dorsal ectoderm. The proneuronal domains are prefigured by the expression of basic helix-loop-helix (bHLH) proneural genes, and separated by domains (inter-proneuronal domains) that do not express the proneural genes. Little is known about how the formation of these domains is spatially regulated. We have found that the zebrafish hairy- and enhancer of split-related (Her) genes her3 and her9 are expressed in the inter-proneuronal domains, and are required for their formation. her3 and her9 expression was not regulated by Notch signaling, but rather controlled by positional cues, in which Bmp signaling is involved. Inhibition of Her3 or Her9 by antisense morpholino oligonucleotides led to ectopic expression of the proneural genes in part of the inter-proneuronal domains. Combined inhibition of Her3 and Her9 induced ubiquitous expression of proneural and neuronal genes in the neural plate, and abolished the formation of the inter-proneuronal domains. Furthermore, inhibition of Her3/Her9 and Notch signaling led to ubiquitous and homogeneous expression of proneural and neuronal genes in the neural plate, revealing that Her3/Her9 and Notch signaling have distinct roles in neurogenesis. These data indicate that her3 and her9 function as prepattern genes that link the positional dorsoventral polarity information in the posterior neuroectoderm to the spatial regulation of neurogenesis.  相似文献   
87.
Ghrelin, produced and secreted by the A-like cells of the stomach, stimulates growth hormone secretion, gastric motility, and food intake. Cysteamine inhibits the release of somatostatin and induces the formation of duodenal ulcers in rats. The present study was conducted to investigate the dynamics of ghrelin secretion in rats treated with cysteamine. Male Wistar rats (7 wk old) were administered three doses of cysteamine (400 mg/kg) orally; at 50 h after the first dose, duodenal ulcers were induced, and the plasma level of somatostatin and gastric density of somatostatin-immunoreactive cells were significantly reduced. The plasma total and active ghrelin levels were significantly higher in the cysteamine-treated rats than in the control rats, whereas the gastric ghrelin levels, number of gastric ghrelin-immunoreactive cells, and preproghrelin mRNA expression levels were significantly lower. Even at the time points of 2 and 10 h after the first dose of cysteamine, at which time no significant ulcer formation or antral neutrophil accumulation was yet noted, a significant increase in the plasma ghrelin level and decrease in the gastric ghrelin level were observed. Furthermore, although lansoprazole treatment attenuated the duodenal ulceration induced by cysteamine, the increase in the plasma level of ghrelin could still be demonstrated. Because an inverse correlation was found between the plasma ghrelin and somatostatin levels, the inhibition of somatostatin secretion may be associated with the increased ghrelin secretion. In conclusion, an increase in the plasma ghrelin level precedes the formation of duodenal ulcers in rats treated with cysteamine.  相似文献   
88.
A rice chitinase cDNA (RCC2) driven by the CaMV 35S promoter was introduced into cucumber (Cucumis sativus L.) through Agrobacterium mediation. More than 200 putative transgenic shoots were regenerated and grown on MS medium supplemented with 100 mg/l kanamycin. Sixty elongated shoots were examined for the presence of the integrated RCC2 gene and subsequently confirmed to have it. Of these, 20 were tested for resistance against gray mold (Botrytis cinerea) by infection with the conidia: 15 strains out of the 20 independent shoots exhibited a higher resistance than the control (non-transgenic plants). Three transgenic cucumber strains (designated CR29, CR32 and CR33) showed the highest resistance against B. cinerea: the spread of disease was inhibited completely in these strains. Chitinase gene expression in highly resistant transgenic strains (CR32 and CR33) was compared to that of a susceptible transgenic strain (CR20) and a control. Different responses for disease resistance were observed among the highly resistant strains. CR33 inhibited appressoria formation and penetration of hyphae. Although CR32 permitted penetration of hyphae, invasion of the infection hyphae was restricted. Furthermore, progenies of CR32 showed a segregation ratio of 3:1 (resistant:susceptible). As the disease resistance against gray mold was confirmed to be inheritable, these highly resistant transgenic cucumber strains would serve as good breeding materials for disease resistance. Received: 31 March 1996 / Revision received: 2 July 1997 / Accepted: 18 July 1997  相似文献   
89.
Hydroxypipecolic acids are bioactive compounds widely distributed in nature and are valuable building blocks for the organic synthesis of pharmaceuticals. We have found a novel hydroxylating enzyme with activity toward l-pipecolic acid (l-Pip) in a filamentous fungus, Fusarium oxysporum c8D. The enzyme l-Pip trans-4-hydroxylase (Pip4H) of F. oxysporum (FoPip4H) belongs to the Fe(II)/α-ketoglutarate-dependent dioxygenase superfamily, catalyzes the regio- and stereoselective hydroxylation of l-Pip, and produces optically pure trans-4-hydroxy-l-pipecolic acid (trans-4-l-HyPip). Amino acid sequence analysis revealed several fungal enzymes homologous with FoPip4H, and five of these also had l-Pip trans-4-hydroxylation activity. In particular, the homologous Pip4H enzyme derived from Aspergillus nidulans FGSC A4 (AnPip4H) had a broader substrate specificity spectrum than other homologues and reacted with the l and d forms of various cyclic and aliphatic amino acids. Using FoPip4H as a biocatalyst, a system for the preparative-scale production of chiral trans-4-l-HyPip was successfully developed. Thus, we report a fungal family of l-Pip hydroxylases and the enzymatic preparation of trans-4-l-HyPip, a bioactive compound and a constituent of secondary metabolites with useful physiological activities.  相似文献   
90.
Bioactivity of human growth hormone in urine from acromegalic patients   总被引:1,自引:0,他引:1  
Bioactivity of hGH in urine from five acromegalic patients was determined by Nb2 bioassay and IM-9 receptor modulation assay (RMA). Urine samples were concentrated by immunoadsorbent chromatography, dialysis and lyophilization. The ratio of the bioactivity by Im-9 RMA and the immunoactivity by RIA was between 0.81 and 1.24 (1.01 +/- 0.19, mean +/- SD). The ratio of the bioactivity by Nb2 bioassay and the immunoactivity ranged from 0.45 to 0.60 (1.37 +/- 0.85). Gel chromatography of hGH in urine samples measured by sensitive sandwich enzyme immunoassay showed that more than 97% of hGH activity was the 22K form. Urinary hGH from acromegalic patients was bioactive in Nb2 bioassay and IM-9 RMA and the bioactivity showed a close correlation with the immunoactivity. The major immunoactive form of hGH (22K) seems to correspond to the bioactivity.  相似文献   
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