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431.
Objective Several potential functional polymorphisms in the DNA base excision repair gene X-ray repair cross-complementing group 1 (XRCC1) have been reported. There has been no information on interindividual variability of Arg194Trp and Arg399Gln polymorphisms of XRCC1 in the Iranian population. Due to the association between the polymorphisms of XRCC1 and the risk of some types of cancers, the present study was done. Methods The genetic polymorphisms of XRCC1 were detected by PCR-based method in 707 healthy individuals from Shiraz population, (Fars province, southern Iran). Results Considering that there was no statistically significant difference between males and females, the sex groups were pooled. The frequencies of 194Trp and 399Gln alleles were 9.05% and 33.95%, respectively. When both polymorphisms were considered, the linkage-disequilibrium was observed (D′ = 0.8986, r 2 = 0.0413, P < 0.00001). Conclusion The present results indicated that the allelic frequencies in Iranian populations showed intermediate frequencies in comparison with European and other Asian countries.  相似文献   
432.
Fresh leaves of 150 individuals from 15 populations representing five putative species of Stachys sect. Fragilicaulis, subsect. Fragiles distributed in the Zagros mountains in western Iran were analyzed for isoenzyme variation. Four enzyme systems (peroxidase, esterase, superoxide dismutase and ascorbate peroxidase) have been studied and a total of 32 bands representing seven putative loci have been analyzed by UPGMA using the Euclidean distances. UPGMA analysis resulted in the recognition of three distinct clusters among the considered populations. The average value of Shannon diversity index (H′) estimated for each population ranged from 0.05 to 2.17. The mean number of bands per isoenzyme ranges from 1.60 to 2.50. The value of Euclidean distance ranges from 0.85 to 3.79. The analysis of isoenzyme variation patterns suggests recognizing following species in Stachys sect. Fragilicaulis subsect. Fragiles: Stachys benthamiana (including Stachys megalodonta), Stachys kurdica (including Stachys ballotiformis) and Stachys asterocalyx. These data also suggest paying more attention to geographical distribution of taxa in Stachys for their taxonomic delimitation. This study provides another strong support for application of electrophoretic analysis of isoenzymes in taxonomy at species level.  相似文献   
433.
434.
The citrus leaf roller (CLR), Archips rosanus, a threatening pest of leaves and fruitlets on fruit trees, which in recent years has led to considerable damage to different citrus trees in some parts of the Mazandaran province of Iran. Insect activity on citrus trees causes the growth of buds and leaves to stop and foliage to dry. Pest oviposition as egg masses occurs on the host tree’s trunk. Eggs spent a year in the hibernation stage and, in the following spring, hatched the first instar larvae that fed on the opened buds. The distributions of CLR egg masses, deposited in 2015–2016, were evaluated on the Thomson novel cultivar (Citrus sinensis L.) in the northern region of Iran. The results showed that the numbers of egg masses laid on the trees at different height ranges of 0–50, 50–100, 100–150 and 150–200 cm were, respectively, 38.65, 33.78, 18.54 and 9.03%. The mean number of A. rosanus eggs per mass, however, was not significant at different heights of the tree. Also, most of the egg masses were laid in the north and south directions in comparison with the west and east directions, with no significant difference in mean number in different geographical directions.  相似文献   
435.
436.
In this faunistic survey, we give distributional records for 48 species and subspecies of Ichneumoninae found in Iran, mainly from Golestan and Azerbaijan-e-Grabi provinces. 13 of these taxa are new for the Iranian fauna. Three Iranian species are new to science and described and illustrated, namely Coelichneumon iranicus Riedel sp. n., Coelichneumon melanocastaneus Riedel sp. n., and Coelichneumon nigrifrons Riedel sp. n.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:BE8AC3A5-D40E-4D78-BB05-C0DEDFC5C47B  相似文献   

437.
The Persian Jird, Meriones persicus, is distributed from Eastern Anatolia to Afghanistan and western Pakistan. Six subspecies were described based on skull features and coat colours, but the validity of these subspecies is uncertain, and no molecular work has ever been conducted on this species. Iran appears to be a key geographical region in which to revise the systematic and evolutionary history of this species, because five of the six subspecies are present in this country. To evaluate the phylogeographical history and taxonomy of this species in Iran, we used a combination of genetic (cytochrome b gene sequences of 70 specimens) and geometric morphometric (2D landmarks on the ventral side of skull of 258 specimens) analyses. We also used ecological niche modelling to make inferences about the evolutionary history of these lineages. Our molecular data highlight the existence of four genetic lineages, but they only partly correspond to the previously described subspecies. Our molecular and morphometric data confirm the validity of M. p. rossicus and show that it has a wider geographical range than previously thought. M. p. gurganensis and M. p. baptistae are genetically very close. The skull of M. p. gurganensis is morphologically distinguishable from other subspecies. The subspecies M. p. persicus and M. p. baptistae are genetically distinct, but morphologically close. Meriones p. ambrosius is genetically close to M. p. persicus, and additional analyses with more specimens are needed to validate its subspecific status. The genetic structure observed in Iran seems to fit the topography and biogeography of the country and emphasize the role of the Abarkooh, Central and Lut deserts as barriers to gene flow. All intraspecific divergent events within the Persian Jird occurred during the last 1.4 My, suggesting that climatic changes probably trigger diversification within this species. Our genetic and species niche modelling results suggest that potential refugial areas persisted during glacial periods for this species in north‐western Zagros Mountains, north‐eastern Alborz Mountains and Kohrud Mountains.  相似文献   
438.
本研究所用标本为7种水生甲虫,均采自伊朗Choghakhor沼泽。通过对水生甲虫的体长和体重的测量,研究其体长-体重关系(LWR)。结果表明: LWR参数b的变动范围在2.315~3.117之间。所有被观察的水生甲虫体长与体重关系明显,相关系数(r2)均高。本研究所得到的这种相互关系可被用于确定甲虫体重,并有助于解决其他的一些生态学问题。本研究所提出的体长-体重关系(LWR)限制于所观察到的标本体长范围。  相似文献   
439.
Maize is one of the most important cereals produced in, and imported into, Iran. The incidences of seed-borne fungi were determined in Iranian maize harvested in 2000 from four major production areas with different climatic conditions, namely Fars, Khuzestan, Kermanshah and Mazandaran provinces. This is the first study to compare the mycoflora of maize in the aforementioned areas. Mycological analyses showed a predominance of Fusarium species (38.5%), followed by Aspergillus species (8.7%), Rhizopus species (4.8%), Penicillium species (4.5%), Mucor species (1.1%), and four other fungal genera. Fusarium verticillioides was the most prevalent species (83% of Fusarium isolates and 52% of the total isolations), with the highest incidence in Mazandaran (59%), a region of Iran with the highest rainfall and relative humidity, high rate of esophageal cancer (EC) and high levels of fumonisins in maize. Aspergillus flavus was the most widely recovered Aspergillus species and 38% of samples were contaminated with this potentially aflatoxigenic fungus. The incidence of A. flavus was highest in Kermanshah, the province with lowest mean minimum temperature. Penicillium species were seen in all the samples and Fars had the highest incidence, with highly significant differences when compared to the other three provinces. Diplodia species were not isolated from any of the samples examined.  相似文献   
440.
For the German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae), the permethrin resistance ratio (RR) was assessed by topical application and by tarsal contact tests, using first-instar nymphs of five strains from Tehran, Iran. Each test was replicated three or four times with 10 nymphs aged 2-3 days; mortality was scored 24h post-treatment. The reference susceptible strain showed LD50 permethrin 0.0175 microl/nymph from topical application, KT50 of 8.41 min and LT50 of 12.82 following tarsal contact with permethrin 15 mg/m2. In four wild strains (F1 generation) the RR varied from 4.14 to 4.7 for mortality after topical application, from 4.2 to 6.45 for mortality and 17-27 for knockdown following tarsal contact tests. Hence, overall knockdown results gave much higher RRs than for mortality data. Resistance ratios based on both methods of treatment were very similar: one strain showed a slightly higher value by topical application (RR 4.6 vs. 4.2, i.e. 1.1-fold difference) whereas the other three strains gave slightly greater RR (1.2-1.4 fold) by tarsal contact. Resistance was abolished by cotreatment with the synergist piperonyl butoxide plus permethrin (ratio 3:1 required for full efficacy), indicating that mixed-function oxidases were inhibited as a major metabolic pathway in all four resistant strains.  相似文献   
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