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1.
Assessment of sperm ubiquitination and DNA fragmentation as sperm functional markers are proposed to complement routine semen analysis. This study focuses on the evaluation of these markers in infertile men with varicocele or exposed to occupational background. The results were compared with normozoospermic men. Semen parameters in both groups were lower than those in the control group. Ubiquitination median, as a marker for functionality of the ubiquitin–proteasome system, was also lower in both groups. The ubiquitination median showed a significant positive correlation with motility in both groups, while it showed only a negative correlation with sperm morphology in the varicocele group. DNA fragmentation showed a significant correlation with semen parameters, in total varicocele and also total exposure groups. In conclusion, significant difference of sperm ubiquitination between normal and study groups further validates that sperm ubiquitination as a potential molecular marker for sperm evaluation in addition to routine semen analysis in clinical laboratories.  相似文献   
2.
There is no effective vaccine for the prevention and elimination of leishmaniasis. For this reason, we assessed the protective effects of DNA vaccines containing LeIF, TSA genes alone, or LeIF–TSA fusion against cutaneous leishmaniasis pEGFP‐N1 plasmid (empty vector) and phosphate buffer saline (PBS) were used as control groups. Therefore, cellular and humoral immune responses were evaluated before and after the challenge with Leishmania major. Lesion diameter was also measured 3–12 weeks after challenge. All immunized mice with plasmid DNA encoding Leishmania antigens induced the partial immunity characterized by increased IFN‐γ and IgG2a levels compared with control groups (p < 0.001). Furthermore, the immunized mice showed significant reduction in mean lesion sizes compared with mice in empty vector and PBS groups (p < 0.05). The reduction in lesion diameter was 29.3%, 34.1%, and 46.2% less in groups vaccinated with LeIF, TSA, and LeIF‐TSA, respectively, than in PBS group at 12th week post infection. IFN/IL‐4 and IgG2a/IgG1 ratios indicated that group receiving LeIF–TSA fusion had the highest IFN‐γ and IgG2a levels. In this study, DNA immunization promoted Th1 immune response characterized by higher IFN‐γ and IgG2a levels and also reduction in lesion size. These results showed that a bivalent vaccine containing two distinct antigens may induce more potent immune responses against leishmaniasis.  相似文献   
3.
Mustard gas (MG), as a chemical warfare agent was used by the Iraqi army in Iran-Iraq conflict against military men in the battlefield in 1985.The serum levels of IgG, IgA and IgM of patients exposed to MG in the battlefield were measured by single radial immunodiffusion from day 3 up to one month after exposure to MG. The serum levels of IgG in patients showed significant decrease on day 3 after exposure to MG. However, the levels of IgG in the serum samples collected from the patients during 4-18 days after exposure to MG were found to increase. The increase in serum IgG levels in the sera of patients which were collected during 19-31 days after exposure to MG was found to be highly significant, surpassing those from the controls. The levels of serum IgA in patients during one month after exposure to MG showed alterations similar to those of serum IgG, however the serum alterations of the patients IgA, comparing to those of the normal controls were not significant. The serum levels of IgM in patients did not show marked alterations during one month after exposure to MG comparing to those of the normal controls. The initial decrease in serum levels of IgG in patients is discussed in terms of a possible leakage of IgG into the skin blisters and into other severely affected parts of the body such as respiratory system, whereas the subsequent increase in serum IgG is interpreted as due to (auto) antigenic stimulation of the patients' immune systems.  相似文献   
4.

Purpose  

The aim of this study was to investigate the survival and development of premature follicles and oocytes from a vitrified-transplanted ovary in a murine experimental model.  相似文献   
5.
Our objectives were to assess sperm alteration and adipose tissue (AT) genes expression related to steroid metabolism subsequent to fatty acids consumption. Twenty‐nine mature male mice were divided into: fat diet (FD; n = 15) and the control group (n = 14). FD group was fed with low level of trans and saturated fatty acids source for 60 days. Sperm parameters, levels of hormones and the mRNA abundance of the target genes in AT were assessed. The sperm concentration, total and progressive motilities were lower in FD group compared to that of control (p < 0.01). Blood estradiol levels increased in FD (p < 0.001), whereas no significant difference was observed in testosterone. The mRNA levels of StAR, CYP11A1, CYP17A1, 17βHSD7 and 17βHSD12 in AT of FD were higher than those of the control (p < 0.05). In contrast, mRNA level of Cyp19a1 in FD was significantly (p < 0.05) lower than that of control. 17βHSD12 and 17βHSD7 (as oestrogenic genes) increased, while 17βHSD5 and 17βHSD3 (as androgenic genes) remained unchanged, indicating that dietary trans/saturated fatty acids affect AT genes expression. Probably, sperm parameters were altered by increment of expression level of genes involved in oestrogenic metabolism rather than those engaged in androgenic metabolism after fatty acids consumption.  相似文献   
6.
7.
Objective To determine the geographical distribution of Leishmania species causing cutaneous leishmaniasis (CL) and to study the genetic heterogeneity of Leishmania major isolates from different endemic areas of Iran. Methods A total of 341 isolates from lesions of patients living in 11 provinces of Iran were grown in culture medium and inoculated to BALB/c mice to detect possible visceralisation. The species were identified by isoenzyme analysis using a battery of six enzymes and kinetoplast (k) DNA‐PCR technique. Genetic variation among L. major isolates was analysed by random amplified polymorphic DNA (RAPD) technique. Results Of the total 341 isolates, 283 isolates were L. major and 58 isolates were Leishmania tropica. In rural areas, the causative agent of CL was mainly L. major (95%L. major vs. 5%L. tropica), in urban areas it was L. tropica (65%L. tropica vs. 35%L. major). All isolates of L. major and 8.6% of L. tropica isolates showed visceralisation in BALB/c mice. There is considerable genetic diversity between L. major strains from different endemic areas and even between some isolates of the same endemic area. Conclusion Leishmania major is the most frequent species in the endemic areas of CL in eleven provinces of Iran, and genetic diversity is a common feature of L. major in the country.  相似文献   
8.
Sarcocystis cameli was first described in one-humped camels (Camelus dromedarius), and it is the only species which have so far reported in camels. Although more than 150 species of Sarcocystis were described in various animals, only a few data on camel Sarcocystis ultrastructure were published, and this report is the first for molecular information (DNA sequence and RLFP digestion pattern). The main objective of the present work is to characterize Sarcocystis isolated from camels by electron microscopy and PCR-RFLP methods. Muscle samples were taken from the fresh esophagus, diaphragm, skeletal muscles, and heart of one-humped camels (C. dromedarius) slaughtered in abattoirs of Tehran and Ghazvin provinces, Iran. The dissection and trypsin digestion techniques were applied for the detection of the cysts. The infected samples were fixed in glutaraldehyde and/or frozen at −20°C until use for ultrastructural and molecular studies, respectively. The ultrastructural and molecular studies were carried out contemporaneously. The 18S rRNA gene of the parasites was amplified by PCR. The PCR products were cloned into a pTZ57R/T and sequenced. In addition, the PCR products were digested separately with each of the four restriction enzymes for RFLP. Our results indicated that only microcysts were observed in muscle samples. The microcysts were white, elongated, spindled, and a few spiral-shaped, with mean size 260 × 75 μm which are identical with S. cameli. The ultrastructure of microcyst wall had many non-branched finger-like protrusions irregularly folded. There was a 600-bp specific band amplified after PCR with specific primers. The molecular data for camel Sarcocystis is reported for the first time in Iran and the world.  相似文献   
9.
Matrix metalloprotainases (MMPs) play an important role in several pathologic processes such as malignancy in which they facilitate invasion and metastasis and can be targets for anticancer therapies. Here, in this study, we investigated the cytotoxicity effect of Cousinia shulabadensis Attar & Ghahraman extract as well as its impact on MMPs activity using a model of cell line (Fibrosarcoma-Wehi164). To assess anti-invasiveness potentials, a modified zymoanalysis method was used to measure MMP-2 and MMP-9 activities in the conditioned-media. The concentration necessary to produce 50% cell death was >80µg/ml for ethanol extract of Cousinia shulabadensis, while a 23 µg/ml concentration of the diclofenac sodium produced the same effect. The invasion of WEHI 164 cells was considerably inhibited at concentrations > 20 µg/ml by total plant extract. The total extract of the plant did not show high toxicity at all tested concentrations, but demonstrated significant inhibition of MMP activity in dose-response fashion.  相似文献   
10.
Hydatid cyst is a chronic zoonotic disease caused by the larval stage of the dog tapeworm, Echinococcus granulosus. To identify genotype of hydatid cysts of human and sheep jackal in Ilam Province (South West of Iran), the PCR-RFLP and DNA sequencing were used. A total of 10 human and 20 sheep protoscoleces hydatid cyst samples were collected from different hospitals and slaughterhouses. Then, the gene of cox1 of mitDNA of the parasite was amplified and PCR products were cut using AluI and HpaII restriction enzymes. Finally, a number of PCR products were bi-directionally sequenced. Based on the DNA sequencing and PCR-RFLP results, human and sheep samples indicated to pertain the genotypic similarities. Our data indicated that, the genotypes of larval stage of E. granulosus is similar in both intermediate hosts. According to the phylogenetic tree, there is at least one genotype of parasite, which belongs to E. granulosous sensu stricto (G1–G3) complex and overall isolates sequences of mtDNA indicated 100 % homology with references G1, G2, and G3 sequences in the GenBank database. G1 genotype was the dominant genotype of human and livestock.  相似文献   
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