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501.
During the past two decades, Iran has experienced a noteworthy growth in its biomedical research sector. At the same time, ethical concerns and debates resulting from this burgeoning enterprise has led to increasing attention paid to biomedical ethics. In Iran, Biomedical research ethics and research oversight passed through major periods during the past decades, separated by a paradigm shift. Period 1, starting from the early 1970s, is characterized by research paternalism and complete reliance on researchers as virtuous and caring physicians. This approach was in concordance with the paternalistic clinical practice of physicians outside of research settings during the same period. Period 2, starting from the late 1990s, was partly due to revealing of ethical flaws that occurred in biomedical research in Iran. The regulatory and funding bodies concluded that it was not sufficient to rely solely on the personal and professional virtues of researchers to safeguard human subjects' rights and welfare. The necessity for independent oversight, emphasized by international declarations, became obvious and undeniable. This paradigm shift led to the establishment of research ethics committees throughout the country, the establishment of academic research centers focusing on medical ethics (MEHR) and the compilation of the first set of national ethical guidelines on biomedical research–one of the first and most important projects conducted by and in the MEHR. Although not yet arrived, ‘period 3’ is on its way. It is predictable from the obvious trends toward performance of high‐quality clinical research and the appearance of a highly educated new generation, especially among women.  相似文献   
502.
The pseudoscorpion Hysterochelifer afghanicus Beier, 1966 is redescribed and illustrated based on 21 specimens (13♂, 8♀) collected from different sites in northern, western, and southern Iran. A number of morphological characters and new provincial records are given. In addition, a key for 13 species of the pseudoscorpion genus Hysterochelifer Chamberlin, 1932 is proposed.  相似文献   
503.
The Gray Toad-headed Agama (Phrynocephalus scutellatus) occurs in Iran, Pakistan and Afghanistan and is represented in Iran by four distinctive genetic clades. We built distribution models for three of these clades (one clade was not included due to a low number of distribution records) using Maximum Entropy Algorithm in order to determine the contribution of ecological factors to the distribution pattern. The degree of spatial niche overlap between every pair of clades were measured using Schoener's D niche overlap metric. The results showed that at species-level climate variables (annual precipitation, annual mean temperature) were the most influential parameters determining the boundaries of the distribution in Iran. Temperature seasonality was found to be the most influential factor in the distribution of both Clade I and Clade II. However, this variable was replaced by the annual mean temperature for Clade VI. Based on the results of Schoener's D metric, Clades I and II had the lowest, and Clades II and VI the highest level of ecological niche overlap. Comparing the result of niche overlap with genetic distance between the clades, it was found that the ecologically least similar clades were those with the longer history of genetic segregation.  相似文献   
504.
A new species, Platycephala isinensis sp. n. (Diptera: Chloropidae) is described from Iran and main differential characters are illustrated.  相似文献   
505.
Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81–0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.  相似文献   
506.
The occurrence of Aphelinus paramali (Zehavi & Rosen) (Hym., Aphelinidae) was evidenced from North east Iran, in association with Aphis pomi (de Geer). This species is reported from Iran for the first time, and A. pomi is introduced as a new host for this parasitoid. Detailed morphological characters were studied with scanning electron microscopy (SEM) photographs. Also, sequences of ribosomal internal transcribed spacer 2 (ITS2) and cytochrome oxidase subunit I (COI) genes were used for determining species boundaries and comparing with other Aphelinus species. Different results were obtained in phylogenetic analysis of these two regions. Analysis of COI gene supported the closer relationship of this species with Aphelinus abdominalis. This is the first data about comprehensive characterization of a parasitic wasp using morphological characters, SEM and two‐locus information from Iran.  相似文献   
507.
Iman Haghiyan 《农业工程》2018,38(6):391-393
In this study the effects of environmental factors on some vegetative characteristics of Quercus brantii was investigated in Kouh gachan, Ilam, West of Iran, using multivariate analysis. Therefore 64 sample plots with a size of 200?m2 were considered for measuring the vegetative parameters. Some environmental factors such as slope, aspect and soil depth were recorded in all sample plots. The Detrended Correspondence Analysis (DCA) was used to investigate the relation between vegetative parameters and environmental factors. Redundancy analysis (RDA) analysis was also used to interpret the results. The results of DCA analysis showed that the effect of environmental factors on vegetation cover is significant. Slope had the smallest and the soil depth had the biggest effect on vegetative characteristics of Quercus brantii. The results also confirmed the usage of RDA analysis for investigating the relationship between environmental factors and vegetative characteristics.  相似文献   
508.
Patients have the right to refuse their treatment; however, this refusal should be informed. We evaluated the quality of the informed refusal process in Iranian hospitals from patients' viewpoints. To this end, we developed a questionnaire that covered four key aspects of the informed refusal process including; information disclosure, voluntariness, comprehension, and provider‐patient relationship. A total of 284 patients who refused their treatment from 12 teaching hospitals in the Isfahan Province, Iran, were recruited and surveyed to produce a convenience sample. Patients' perceptions about the informed refusal process were scored and the mean scores of the four components were calculated. The findings showed that the practice of information disclosure (9.6 ± 6.4 out of 22 points) was perceived to be moderate, however, comprehension (2.3 ± 1.4 out of 4 points), voluntariness (8.7 ± 1.5 out of 12 points) and provider–patient relationship (10.2 ± 5.2 out of 16 points) were perceived to be relatively good. We found that patients, who refused their care before any treatment had commenced, reported a lower quality of information disclosure and voluntariness. Patients informed by nurses and those who had not had a previous related admission, reported lower scores for comprehension and relationship. In conclusion, the process of obtaining informed refusal was relatively satisfactory except for levels of information disclosure. To improve current practices, Iranian patients need to be better informed about; different treatment options, consequences of treatment refusal, costs of not continuing treatment and follow‐ups after refusal. Developing more informative refusal forms is needed.  相似文献   
509.
A study of the distribution and ecology of mosquitoes (Diptera: Culicidae) in Ardebil Province of northwestern Iran, with special reference to the known dirofilariasis focus in Meshkinshahr County, was carried out in July‐August 2005 and April‐October 2006. In total, 17 533 adult mosquitoes and 3090 third‐ and fourth‐instar larvae were collected on 14 occasions and identified using morphological characters and DNA sequence data. Twenty species belonging to seven genera were found: Anopheles claviger (Meigen), An. hyrcanus (Pallas), An. maculipennis Meigen, An. pseudopictus Grassi*, An. sacharovi Favre, An. superpictus Grassi, Aedes vexans (Meigen)*, Coquillettidia richiardii (Ficalbi)*, Culex hortensis Ficalbi, Cx. modestus Ficalbi, Cx. pipiens Linnaeus, Cx. theileri Theobald, Cx. torrentium Martini*, Cx. tritaeniorhynchus Giles, Culiseta longiareolata (Macquart), Cs. annulata (Schrank)*, Cs. subochrea (Edwards), Ochlerotatus caspius (Pallas) s.l.* (= Aedes caspius sensu auctorum), Oc. geniculatus (Olivier)* (= Aedes geniculatus sensu auctorum) and Uranotaenia unguiculata Edwards (asterisks indicate new occurrence records for the province). The most prevalent species in adult catches were An. maculipennis (52%), Cx. theileri (45%) and Cx. hortensis (1%); the most prevalent species caught as larvae were Cx. theileri (27%), Cx. hortensis (21%) and An. maculipennis (19%). Anopheles maculipennis, Cx. pipiens and Cx. theileri were most widely distributed in the province. The occurrence of Cx. torrentium in Iran is verified based on differential characters of fourth‐instar larvae. Anopheles maculipennis and An. sacharovi of the Maculipennis Group were identified from their diagnostic ITS2 sequences. For the first time, cytochrome c oxidase I (COI) sequences were obtained from Iranian specimens of An. hyrcanus, An. pseudopictus, Cx. theileri and Oc. caspiuss.l. Culex theileri and An. maculipennis were found naturally infected with third‐stage (infective) larvae of Dirofilaria immitis (Leidy) and Setaria labiatopapillosa (Alessandrini) (Spirurida: Onchocercidae), respectively, for the first time in Iran.  相似文献   
510.
Trichomes of 26 species of Alcea (Malvaceae) were investigated using light (LM) and scanning electron microscopy (SEM). The trichomes show a great micromorphological variation, which provides data useful for species delimitation in Alcea. Two basic types of trichomes could be distinguished in Alcea and allied genera: glandular and eglandular. The glandular trichomes could in turn be subdivided into two subtypes: capitate and clavate. The eglandular trichomes could be subdivided into five subtypes: simple, fascicled, stellate, fascicled-stellate and pluri-radiate. Characters of taxonomic interest are: trichome density (glabrous to dense), number of arms per trichome, orientation relative to the epidermal surface (appressed to erect) and presence/absence of a stalk. According to the results the species of Alcea can be divided into four informal groups based on trichome types. The results further support the exclusion of the annual Althaea species from the perennial ones and their close relationship to Malva. In addition, a close relationship between perennial Althaea and basal Alcea lineages is supported. Based on the evolutionary framework provided by recent molecular phylogenetic investigations, the following trends can be observed in the Malva alliance: long and narrow-armed trichomes are primitive in relation to short and thick-armed trichomes; dense indumentum coverage is primitive in relation to moderately dense or glabrous ones; presence of simple hairs on stem (particularly on leaves) is more advanced than their absence; spreading villous-stellate and fascicled trichomes are more advanced than appressed stellate ones. Clavate trichomes, which were found exclusively in a few species of Alcea, should be considered as a derived state in relation to capitate ones, and they may provide a synapomorphy for the crown group of Alcea.  相似文献   
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