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31.
Human carbonic anhydrase isoenzymes I and II (HCA I and II) were purified from human erythrocytes by inhibitor affinity chromatography and ion-exchange chromatography. These isoenzymes were then located in the human adrenal gland using specific polyclonal antisera raised in rabbits and specific detection by immunohistochemical techniques. Both HCA II and I were located in the zona glomerulosa cells, although the staining for HCA I was faint. The cells of the zona fasciculata and the zona reticularis failed to stain with either antiserum. Control stainings with preimmune or anti-HCA VI sera were negative. The presence of HCA II and I in the zona glomerulosa cells may be linked to regulation of the biosynthesis or secretion of mineralocorticoids.  相似文献   
32.
The localization of human carbonic anhydrase (CA) isoenzymes HCA I, HCA II, and rat CA II have been studied in human umbilical cord, chorion laeve including amnion and placenta from first and second trimester and also from term pregnancies. Detection techniques of immunofluorescence and immunoperoxidase were used in cryostat and paraffin sections. Both isoenzymes were found in the villous syncytiotrophoblast throughout pregnancy. HCA I staining patterns in the villous endothelium were highly variable whereas increasing immunoreactivity levels of endothelial HCA II were detected as pregnancy advances. The extravillous cytotrophoblast showed generally weaker levels of immunoreactivity. In amnionic epithelium of membranes, chorionic plate and umbilical cord, higher activities for HCA I, HCA II and rat CA II were found than in all other localizations. Our findings emphasize the importance of enzyme mediated bicarbonate/CO2 removal from the feto-placental unit as opposed to simple bicarbonate diffusion or carrier mediated transport. As effective transfer routes should be considered not only umbilical cord — placental villi — intervillous space, but also fetal kidney — amnionic fluid — amnion — uterine vessels.  相似文献   
33.
It is of interest to evaluate the clinical characteristics, treatment patterns, clinical effectiveness, and safety of telmisartan as a monotherapy or as part of combination therapy in Indian adults (>18 years old) with hypertension. All patients were receiving telmisartan as monotherapy, or as a combination therapy for hypertension management. Demographics, risk factors, existing comorbidity, and ongoing medical therapies were retrieved from the patients’ medical records. A total of 8607 patients with hypertension (median age, 51.0 years) were part of the study. The gender distribution suggested, 5534(64.3%) patients were male, and 3073 (35.7%) were female patients. The excess salt intake (39.0%) was the most common risk factor according to the results. The analysis revealed telmisartan dual therapy (57.9%) as the most prescribed therapy, followed by monotherapy (32.5%), and triple therapy (9.6%). Further, telmisartan 40mg (21.3%) and telmisartan 40mg plus amlodipine 5mg (17.6%) were the most commonly prescribed therapies. The data suggested that only 17.2% of patients required dose titration. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) (mmHg) were significantly decreased with monotherapy (mean change: 19.8 [15.1] mmHg and 8.8[8.2] mmHg), dual therapy (mean change: 23.7 [16.6] mmHg and 10.3[8.5] mmHg), and triple therapy (mean change: 28.6 [19.0] mmHg and 12.1[10.8] mmHg) after the treatment (P<0.001). A total of 98.4% of the patients were compliant, and 97.6% achieved the target blood pressure goal with telmisartan-based therapy. There were 157 adverse events reported altogether. The Physicians'' global evaluation of efficacy and tolerability showed the majority of the patients receiving telmisartan-based therapy on a good to excellent scale. Telmisartan used as a monotherapeutic agent or as a part of combination therapy was successful and effective in reducing blood pressure and achieving the blood pressure target. Irrespective of the patient’s age, duration, and stages of hypertension, the study resulted in a good to excellent scale in efficacy and tolerability in the Indian patients having hypertension.  相似文献   
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Our previous study has shown that chronic exposure to tamoxifen (TAM) induced formation of high levels of DNA adducts in the liver, the target tissue of TAM-induced carcinogenesis in rats. One of the major DNA adducts (spot 1), as detected by 32P-postlabeling, accounted for 53% of the total adducts. To characterize this major adduct, the current study has compared spot 1 with two previously identified TAM-DNA adducts, i.e. alpha-TAM-N2-deoxyguanine (alpha-TAM-N2-dG) and alpha-N-desmethyl TAM-N2-deoxyguanine (alpha-N-dmTAM-N2-dG) by various rechromatography methods. It was found that spot 1 was further resolved into two fractions during rechromatography analysis, one fraction co-migrated with the alpha-TAM-N2-dG and the other fraction co-migrated with the alpha-N-dmTAM-N2-dG. These findings have demonstrated that chronic exposure to tamoxifen induced the same major DNA adducts, i.e. alpha-TAM-N2-dG and alpha-N-dmTAM-N2-dG as those detected in acutely exposed rats.  相似文献   
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37.
Abstract. The effects of competition on individual fitness and species diversity were investigated in a first‐year old field by comparing the natural community to an experimentally‐determined null community. The species pool for the null community was estimated from low‐density plots, and hypothetical sample plots in the null community were constructed by random sampling from the species pool. Individual plants were larger in low‐density plots than control plots, indicating that competition reduced individual fitness. Competition appeared to reduce diversity in half the plots (i.e. species richness and diversity were lower than in hypothetical null community plots with the same number of individuals), but did not affect diversity in the other plots. However, the reduction in diversity could be explained as an artifact caused by spatial aggregation in control plots. The magnitude of the effects of competition on diversity did not change with plot density, and no species consistently increased or decreased in relative abundance as plot density increased. We conclude that competition had no effect on diversity in this community, despite the strong effect on individual growth.  相似文献   
38.
Three strains of Limnothrix (Cyanobacteria) isolated from Lake Kastoria, Greece, were characterized based on their morphological features and 16S rRNA gene sequences. The Limnothrix isolates 007a, 165a, and 165c can morphologically be assigned to Limnothrix redekei (Van Goor) Meffert. The 16S rRNA gene of the Limnothrix strains showed a 99% similarity to the 16S rRNA gene of Planktothrix sp. FP1. Limnothrix redekei strains 165a, 165c, 007a and Planktothrix sp. FP1 formed a separate cluster in the cyanobacterial 16S rRNA gene tree. It was distinct from the Pseudanabaena cluster, which included the other Limnothrix strains isolated from northern temperate lakes. This is the first report on the phylogeny of L. redekei strains originating from a Mediterranean lake (southern Europe) and provides new data about the genus Limnothrix.  相似文献   
39.
Summary Ovine pituitary gonadotrophins (FSH and LH) were labelled with 125I using an enzymatic method consisting of lactoperoxidase, hydrogen peroxide and iodide. High specific radioactivity was obtained. Radioiodination did not alter the electrophoretic mobility or biological activity of the hormones, the antigenity of LH remained unchanged after the labelling. When the enzymic method was compared to chloramine-T oxidation method far less radioiodine could be incorporated in the gonadotrophins when latter method was used.The radioautographic localization of the labelled gonadotrophins in the ovary and testis of mature rats was observed 1.5 hrs after the hormone injection. FSH produced silver grains in the granulosa cells and liquor of follicles, and LH in the interstitial gland cells of the ovary. Both hormones were mainly in the interstitial cells of the testis, but some FSH was also in the tubules.This study was supported by the Sigrid Jusélius Foundation, Helsinki.  相似文献   
40.
A new modification of the 32P postlabelling method was described for the analysis of lipophilic DNA in human tissues. To isolate these DNA adducts the method applied nuclease P1 enrichment before labelling and butanol extraction after labelling, followed by high performance liquid chromatography HPLC separation and flow through radioactivity detection. These enrichment methods are known to work for many adducts of polycyclic aromatic hydrocarbons PAHs . In human peripheral lung tissue fro m smokers the apparent level of the DNA adducts observed was 25-244 adducts per 108 nucelotides; in two alleged non smokers the level of adducts was 17 and 109 adducts per 108 nucleotides. When the same samples were analysed by thin layer chromatography TLC , as in the conventional postlabelling assay, the recovery was 5 of that of the HPLC method. Nevertheless, the results from the two methods correlated. In TLC the adducts were lost because they did not remain in the origin in D1 of the TLC development. There was no large difference in recovery between the two techniques for the PAH-DNA adduct standards used. The present results are underestimates of the true adduct levels because there is no way to correct for labelling efficiency and recovery of unknown adducts. Yet they give a lower estimate of the level of lipophilic DNA adducts in human lung tissue.  相似文献   
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