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21.
Three population samples from Iran (Tabriz, Yazd, Mashhad) have been typed for four enzyme group polymorphisms: ACP1, ESD, AK, and PGD. The phenotype and allele frequencies are presented and compared with other Iranian populations. The AK allele frequencies do not show significant intergroup heterogeneity, whereas ACP1, ESD and PGD allele frequencies disclose obvious heterogeneity. The possible reasons therefore are discussed.  相似文献   
22.
The bacterium Helicobacter pylori colonizes the human stomach, with individual infections persisting for decades. The spread of the bacterium has been shown to reflect both ancient and recent human migrations. We have sequenced housekeeping genes from H. pylori isolated from 147 Iranians with well-characterized geographical and ethnic origins sampled throughout Iran and compared them with sequences from strains from other locations. H. pylori from Iran are similar to others isolated from Western Eurasia and can be placed in the previously described HpEurope population. Despite the location of Iran at the crossroads of Eurasia, we found no evidence that the region been a major source of ancestry for strains across the continent. On a smaller scale, we found genetic affinities between the H. pylori isolated from particular Iranian populations and strains from Turks, Uzbeks, Palestinians and Israelis, reflecting documented historical contacts over the past two thousand years.  相似文献   
23.
Expression of the full set of human and mouse groups I, II, V, X, and XII secreted phospholipases A(2) (sPLA(2)s) in Escherichia coli and insect cells has provided pure recombinant enzymes for detailed comparative interfacial kinetic and binding studies. The set of mammalian sPLA(2)s display dramatically different sensitivity to dithiothreitol. The specific activity for the hydrolysis of vesicles of differing phospholipid composition by these enzymes varies by up to 4 orders of magnitude, and yet all enzymes display similar catalytic site specificity toward phospholipids with different polar head groups. Discrimination between sn-2 polyunsaturated versus saturated fatty acyl chains is <6-fold. These enzymes display apparent dissociation constants for activation by calcium in the 1-225 microm range, depending on the phospholipid substrate. Analysis of the inhibition by a set of 12 active site-directed, competitive inhibitors reveals a large variation in the potency among the mammalian sPLA(2)s, with Me-Indoxam being the most generally potent sPLA(2) inhibitor. A dramatic correlation exists between the ability of the sPLA(2)s to hydrolyze phosphatidylcholine-rich vesicles efficiently in vitro and the ability to release arachidonic acid when added exogenously to mammalian cells; the group V and X sPLA(2)s are uniquely efficient in this regard.  相似文献   
24.

Background

The objective of this study is to determine the effect of a consultation model, Beliefs, Attitudes, Subjective Norms and Enabling Factors (BASNEF), and the counselling steps using GATHER-Greet clients, Ask clients about themselves, Tell clients about their choices, Help clients choose, Explain what to do, and Return for follow-up-on the continuation rates of exclusive breastfeeding in mothers of premature infants.

Methods

This is a randomized controlled clinical trial carried out on 124 mothers with premature infants hospitalized in Fatemieh Hospital, city of Hamadan, in 2014. Participants were randomly assigned to either the intervention or control groups. The initial demographic questionnaire carried out in both groups included three questions about the continuation of exclusive breastfeeding, BASNEF, a checklist related to the lactation performance documented by mothers and the weight gain of their infants. Five breastfeeding consultation sessions based on the BASNEF model and counselling steps using GATHER, were held for the mothers in the intervention group for five consecutive days. Then follow-up weight gain and the questionnaire completion were performed in both groups at 1, 2, 3 and 4 months after the intervention.

Results

Baseline characteristics were similar in the two groups. There were no significant differences between both groups in the rate of exclusive breastfeeding, lactation performance and infant weight at baseline. The intervention group had significantly higher rates of exclusive breastfeeding, 72.6% versus the control group of 16.1%, at the end of the 4 month follow-up. Also the intervention group had significantly higher mean scores of lactation performance (8.62?±?2.08 vs 6.40?±?1.84 in the control group) and infant weight (5694.80?±?779.43 vs 4760.17?±?859.12 in the control group) at the end of the 4 month follow-up.

Conclusion

Breastfeeding consultation of mothers based on the BASNEF model and using GATHER counselling steps increased the rate of exclusive breastfeeding, lactation performance and weight gain of premature infants. Therefore, breastfeeding counselling sessions are recommended for all mothers of premature infants.

Trial registration

Iranian Registry of Clinical Trials number IRCT2014111013405N6 and date registered, January 5, 2015.
  相似文献   
25.
A series of 5-(nitroaryl)-1,3,4-thiadiazoles bearing certain sulfur containing alkyl side chain similar to pendent residue in tinidazole molecule were synthesized and evaluated against Helicobacter pylori using disk diffusion method. The synthesized compounds were also evaluated for their antibacterial, antifungal and cytotoxic effects. Study of the structure-activity relationships of this series of compounds indicated that both the structure of the nitroaryl unit and the pendent group on 2-position of 1,3,4-thiadiazole ring dramatically impact the anti-H. pylori activity. While compound 7a containing 2-[2-(ethylsulfonyl)ethylthio]-side chain from nitrothiophene series was the most potent compound tested against clinical isolates of H. pylori, however, nitroimidazoles 6c and 7c were found to be more promising compounds because of their respectable anti-H. pylori activity besides less cytotoxic effects.  相似文献   
26.
Cousinia kermanensis sp. nov. (sect. Congestae Bunge) and C. pulcherantha sp. nov. (sect. Leiocaules Bunge) are described from Kerman in southeastern Iran. These species are compared to their closest related species, C. decurrens Regel and C. oophora Rech. f., respectively. The habitat of C. kermanensis is lowland mountains or hills with poor soils inside the steppe of Artemisia sieberi Besser. Cousinia pulcherantha grows on highland slopes of mountains with deep soils inside the steppe of Artemisia aucheri Boiss. Illustrations of the new species are presented.  相似文献   
27.
The crystal structure of human group X (hGX) secreted phospholipase A2 (sPLA2) has been solved to a resolution of 1.97 A. As expected the protein fold is similar to previously reported sPLA2 structures. The active site architecture, including the positions of the catalytic residues and the first and second shell water around the Ca2+ cofactor, are highly conserved and remarkably similar to the group IB and group IIA enzymes. Differences are seen in the structures following the (1-12)-N-terminal helix and at the C terminus. These regions are proposed to interact with the substrate membrane surface. The opening to the active site slot is considerably larger in hGX than in human group IIA sPLA2. Furthermore, the electrostatic surface potential of the hGX interfacial-binding surface does not resemble that of the human group IIA sPLA2; the former is highly neutral, whereas the latter is highly cationic. The cationic residues on this face of group IB and IIA enzymes have been implicated in membrane binding and in k(cat*) allostery. In contrast, hGX does not show activation by the anionic charge at the lipid interface when acting on phospholipid vesicles or short-chain phospholipid micelles. Together, the crystal structure and kinetic results of hGX supports the conclusion that it is as active on zwitterionic as on anionic interfaces, and thus it is predicted to target the zwitterionic membrane surfaces of mammalian cells.  相似文献   
28.
29.
In this study, micromorphological features of the leaf epidermal cells of 17 species of Iranian Cotoneaster were determined. The studied species were compared with each other and with phylogenetic relationships established by previous studies. Three populations of C. integerrimus and C. multiflorus were studied as representatives of C. subgen. Cotoneaster and Chaenopetalum, respectively. To evaluate quantitative and qualitative characters, multiple correspondence analysis (MCA) and factor analysis of mixed data (FAMD) were performed. Finally, relationships among the taxa were illustrated by hierarchical clustering analysis. Three stomatal types were identified, i.e. anomocytic, stephanocytic and actino‐stephanocytic. The wax and cuticle density was higher in species from semi‐moist habitats than in those from dry and semi‐dry habitats. The patterns formed by the anticlinal walls of the epidermal cells were sinuous, repand and straight‐curved. Interestingly, there was a significant relationship between the length of leaves, the density of the indumentum and the pattern formed by the anticlinal cell walls. The leaves of species with large leaves also have lower hair density and more curved anticlinal cell walls. It appears probable that climatic conditions affected the evolution of leaf micro‐morphological characters during the early diversification of the genus, but that these characters have subsequently been permanently fixed by phylogenetic constraints and thus appear diagnostic for extant species.  相似文献   
30.
IntroductionTo investigate the course of functional status assessed by health assessment questionnaire (HAQ) in rheumatoid arthritis (RA) patients with sustained clinical remission (REM).MethodsIn recent RA clinical trials, we identified patients with subsequent visits of ≥24 weeks in clinical REM according to the disease activity score using 28-joint counts including C-reactive protein (DAS28) (≤2.6), or simplified disease activity index (SDAI) (≤3.3). Area under the curve (AUC) and mean HAQ scores throughout the time in sustained REM were compared using t test, analyses of variance (ANOVA) and adjusted general linear modeling (GLM) with repeated measures. In Cox regression analyses, the time to regain full physical function was modeled. Sensitivity analyses were performed in patients of sustained SDAI low disease activity (LDA; SDAI ≤11).ResultsA total of 610 out of 4364 patients achieved sustained DAS28 REM (14 %) and 252 SDAI REM (5.8 %). ANOVA testing for linear trend showed significant decrease of mean HAQ from week 0 (start of REM) to week 24, regardless of REM criteria used. AUC of HAQ throughout 24 weeks of REM was higher in DAS28 compared to SDAI REM (p ≤0.01). GLM adjusting for covariates showed significant decrease of monthly HAQ scores from week 0 to 24 (DAS28: 0.276, 0.243, 0.229, 0.222, 0.219, 0.209 to 0.199; p = 0.0001; SDAI: 0.147, 0.142, 0.149, 0.129, 0.123, 0.117 to 0.114; p = 0.029). Similarly, a decrease of HAQ over time was found in patients of sustained SDAI LDA. In DAS28 REM, the chance of regaining full physical function was higher for female (hazard ratio HR [95 % confidence interval]: 1.41 [1.13–1.76]) and early RA patients (disease duration ≤2 years: HR 1.29 [1.01–1.65]); in SDAI REM no significant differences were found.ConclusionsPhysical function continues to improve if the target of REM or LDA is sustained. The stringency of the remission criteria determines achievement of the best possible functional improvement.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0719-x) contains supplementary material, which is available to authorized users.  相似文献   
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