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31.

Background

Type 2 diabetes is a common metabolic disease with the potential for prevention of complications. The prevention requires a high level of lasting actions from the patients, which may be burdensome. The aim of this trial was to evaluate the effectiveness of a training course for general practice nurses in motivation support at 18 months follow-up in the affiliated type 2 diabetes population.

Methods

Forty general practices with nurse-led diabetes consultations from the area of Aarhus, Denmark were randomised 1∶1 to either intervention or usual practice. Intervention practices were offered a 16-hour Self-determination theory - based course including communication training for general practice nurses delivered over 10 months. The affiliated diabetes populations (aged 40–74 years) were identified from registers (intervention n = 2,005; usual n = 2,029). Primary outcomes were register-based glycated haemoglobin (HbA1c) -, total cholesterol levels, and well-being measured by the Problem Areas In Diabetes scale (PAID) and the mental component summary score, SF12 (SF12, mcs). Intention-to-treat analyses were performed. Predefined subgroups analyses were performed.

Results

The differences between the intervention- and the control practices’ mean HbA1c and total cholesterol at follow-up adjusted for baseline values and clustering were respectively: −0.02%-points (95% CI: −0.11 to 0.07; p: 0.67); 0.08 mmol/l (95% CI: 0.01 to 0.15; p: 0.02). Differences in median scores adjusted for clustering were for PAID: 1.25; p = 0.31 and SF12, mcs: 0.99; p = 0.15. Women in intervention practices differed from women in usual practices on mean HbA1c: −0.12%-points (−0.23 to −0.02; p = 0.02) and SF12, mcs: 2.6; p = 0.01.

Conclusions

Offering a training course for general practice nurses in applying the Self-determination theory in current type 2 diabetes care had no effect compared with usual practice measured by HbA1c and total cholesterol levels and the well-being at 18 months of follow-up in a comprehensive register-based diabetes population. Subgroup analyses suggested a possible effect in women, which deserves further attention.

Trial Registration

ClinicalTrials.gov (Identifier NCT01187069).  相似文献   
32.
Summary Adenosine deaminase complexing protein (ADCP), a dimeric glycoprotein, has been reported to be decreased or deficient in transformed or cancer-derived cell lines, indicating its potential significance as an indicator of malignant transformation. A similar deficiency was reported in total homogenates of tumours of colon, kidney, lung and liver. In previous biochemical studies we failed to confirm the consistent reduction in ADCP concentration in cancer tissues. A possible explanation for our findings was thought to be intercellular heterogeneity in ADCP expression in individual tumour cells. To study ADCP expression in individual cells we developed an immunohistochemical method which was applied to tissue sections. Paraformaldehyde-lysine-periodate (PLP) solution was found to be a suitable fixative. Fixed tissue samples were paraffin-embedded, sectioned and stained for ADCP, using an indirect peroxidase-labelled antibody procedure. The protein was localized in normal colonic mucosa, mainly in the brush border region of the luminal epithelium and in cytoplasmic granules. Intense ADCP immunoreactivity was found also in the basal part of some cells. In cancer cells, three staining patterns were observed: membranous, diffuse cytoplasmic and granular cytoplasmic. The adenocarcinomas exhibited significant intratumour and intertumour heterogeneity in their staining types.Further studies on ADCP expression in colorectal cancer in relation to clinical and histopathological characteristics are warranted in order to fully evaluate the potential significance of ADCP as a cancer associated antigen.  相似文献   
33.
When isolated rat mesenteric small arteries were submitted to 2 s of sonication, a nucleoside triphosphatase activity was released to the medium, mainly from the plasma membrane of the vascular smooth muscle cells. The activity was kinetically characterized: It hydrolysed ATP, UTP and GTP with the same substrate affinity and the same specific activity. CaATP, as well as MgATP were substrates for the enzyme with an apparent Km in the micromolar range. ATPase inhibitors: ouabain, vanadate, AlF4-, oligomycin and N-ethylmaleimide were without effect on the hydrolytic activity. Among other modifiers tested only N,N'-dicyclohexylcarbodiimide caused significant (greater than 30%) inhibition. In the presence of micromolecular concentrations of Ca2+ and Mg2+, small (less than 20 mM) concentrations of Na+, K+, Rb+, Cs+ and choline+, irrespective of the nature of the anion, activated the hydrolysis with an equilibrium ordered pattern, but concentrations of monovalent cation salts above 20 mM decreased the hydrolysis rate. No activation by monovalent cation salts was seen at millimolar concentrations of divalent cations and substrate. On the basis of the results a standard mixture is proposed, which allows a sensitive assay of the specific enzyme activity.  相似文献   
34.
Segments of isolated intact rat mesenteric small arteries were incubated in physiological bicarbonate buffer in the presence of nano- to millimolar concentrations of ATP. ATP was hydrolysed, and when the vessel was transferred from one incubation to another, the enzyme activity was transferred with the vessel, consistent with the presence of an ecto-ATPase. The substrate, ATP, was shown to induce a modification of the hydrolytic activity which occurred the more rapidly the higher the concentration of ATP. The modified system hydrolysed ATP with a decreased substrate affinity. As the substrate induced a modification of the hydrolytic activity, steady-state velocity measurements for determination of kinetic parameters could not be obtained. Nevertheless, it was possible to compare the modification caused by ATP and UTP, and to compare the hydrolysis rates measured with [32P]ATP, [32P]UTP and [32P]GTP. It was concluded that the hydrolytic activity of the vessels did not distinguish between the nucleoside triphosphates (NTPs). In a histidine buffer, the activity was shown to be activated by micromolar concentrations of either Ca2+ or Mg2+, and not to be influenced by inhibitors of P-type, F-type and V-type ATPases. Functional removal of the endothelium before assay did not reduce the measured NTP hydrolysis. At millimolar concentrations of trinucleotide the hydrolysis rate was 10-15 mumol per min per gram of tissue or 0.11-0.17 mumol per min per 10(6) vascular smooth muscle cells. This value is equivalent to the maximal velocity obtained for the Ca2+ or Mg(2+)-dependent NTPase released to the medium upon 2 s of sonication of the vessels (Plesner, L., Juul, B., Skriver, E. and Aalkjaer, C. (1991) Biochim. Biophys. Acta 1067, 191-200). Comparing the characteristics of the released NTPase to the characteristics of the activity of the intact vessel, they showed a strong resemblance, but the substrate-induced modification of the enzyme was seen only in the intact preparation.  相似文献   
35.

Questions

The rapid climate warming in tundra ecosystems can increase nutrient availability in the soil, which may initiate shifts in vegetation composition. The direction in which the vegetation shifts will co‐determine whether Arctic warming is mitigated or accelerated, making the understanding of successional trajectories urgent. One of the key factors influencing the competitive relationships between plant species is their access to nutrients, depending on the depth where they take up most nutrients. However, nutrient uptake at different soil depths by tundra plant species that differ in rooting depth is unclear.

Location

Kytalyk Nature Reserve, northeast Siberia, Russia.

Methods

We injected 15N to 5 cm, 15 cm and the thaw front of the soil in a moist tussock tundra. The absorption of 15N by grasses, sedges, deciduous shrubs and evergreen shrubs from the three depths was compared.

Results

The results clearly show a vertical differentiation of N uptake by these plant functional types, corresponding to their rooting strategy. Shallow‐rooting dwarf shrubs were more capable of absorbing nutrients from the upper soil than from deeper soil. Deep‐rooting grasses and sedges were more capable of absorbing nutrients from deeper soil than the dwarf shrubs. The natural 15N abundances in control plants also indicate that graminoids can absorb more nutrients from the deeper soil than dwarf shrubs.

Conclusions

Our results show that graminoids and shrubs in the Arctic differ in their N uptake strategies, with graminoids profiting from nutrients released at the thaw front, while shrubs mainly forage in upper soil layers. Our results suggest that tundra vegetation will become graminoid‐dominated as permafrost thaw progresses and nutrient availability increases in the deep soil.  相似文献   
36.
37.
38.
Alteration of the global nitrogen (N) cycle because of human‐enhanced N fixation is a major concern particularly for those ecosystems that are nutrient poor by nature. Because Sphagnum‐dominated mires are exclusively fed by wet and dry atmospheric deposition, they are assumed to be very sensitive to increased atmospheric N input. We assessed the consequences of increased atmospheric N deposition on total N concentration, N retention ability, and δ15N isotopic signature of Sphagnum plants collected in 16 ombrotrophic mires across 11 European countries. The mires spanned a gradient of atmospheric N deposition from about 0.1 up to about 2 g m?2 yr?1. Mean N concentration in Sphagnum capitula was about 6 mg g?1 in less polluted mires and about 13 mg g?1 in highly N‐polluted mires. The relative difference in N concentration between capitulum and stem decreased with increasing atmospheric N deposition, suggesting a possible metabolic mechanism that reduces excessive N accumulation in the capitulum. Sphagnum plants showed lower rates of N absorption under increasing atmospheric N deposition, indicating N saturation in Sphagnum tissues. The latter probably is related to a shift from N‐limited conditions to limitation by other nutrients. The capacity of the Sphagnum layer to filter atmospheric N deposition decreased exponentially along the depositional gradient resulting in enrichment of the mire pore water with inorganic N forms (i.e., NO3?+NH4+). Sphagnum plants had δ15N signatures ranging from about ?8‰ to about ?3‰. The isotopic signatures were rather related to the ratio of reduced to oxidized N forms in atmospheric deposition than to total amount of atmospheric N deposition, indicating that δ15N signature of Sphagnum plants can be used as an integrated measure of δ15N signature of atmospheric precipitation. Indeed, mires located in areas characterized by greater emissions of NH3 (i.e., mainly affected by agricultural activities) had Sphagnum plants with a lower δ15N signature compared with mires located in areas dominated by NOx emissions (i.e., mainly affected by industrial activities).  相似文献   
39.
Light microscopic sperm cell analysis and DNA flow cytometry in the seminal fluid were done in 85 testicular cancer patients after orchiectomy before further treatment. The results were compared with those from 26 healthy age-matched males (control group). A computer-based method for analysis of the DNA histograms was developed for evaluation of the percentage of sperm cells within the sub-haploid, haploid (1c), and diploid (2c) and greater than 2c levels. Compared with the control group, testicular cancer patients had a reduced sperm cell density and sperm cell motility. The mobility grade was also significantly reduced as compared with healthy males. In addition, the number of condensed haploid sperm cells (within the subhaploid level) was decreased in testicular cancer patients, whereas the percentages of noncondensed haploid (1c), diploid, and greater than 2c cells were increased. Most of the DNA flow cytometric parameters were significantly correlated with sperm cell density. DNA flow cytometry in human seminal fluid offers a possible means of assessing spermatogenesis, thus providing an objective method for studying fertility disturbances, for example, in cancer patients before and after treatment.  相似文献   
40.
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