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91.
Preeclampsia remains a leading cause of maternal and perinatal mortality and morbidity worldwide; however, its specific etiology still remains obscure. Some studies implicate poor maternal selenium status predisposing the mother to preeclampsia. This study was designed to determine changes in plasma selenium levels in women having preeclampsia as compared with those with normal pregnancy. In a nested case–control study, 650 normal primigravida in their first 24–28 weeks participated in the study. After 3 months of follow-up of all subjects, blood selenium levels were measured in 38 women presenting consecutively with preeclampsia and in 38 women having a normal pregnancy by atomic absorption spectrophotometry. Birth outcomes were recorded, such as gestational age at delivery, height, weight, birth head circumflex and 1-min Apgar score. Preeclampsia affects about 5.84 % of pregnancies, and in our study, there were no significant differences in age, anthropometric indices, and family history of preeclampsia between the preeclamptic and control groups. The selenium concentrations in plasma in women with preeclampsia were significantly lower as compared with those in women with normal pregnancy (70.63?±?21.41 versus 82.03?±?15.54 μg/L, p?<?0.05). Being in the bottom tertile of selenium concentration (less than 62.2 μg/L) was associated with greater risk of preeclampsia in pregnant women. The reduced selenium in the maternal circulations observed in the preeclamptic mothers support the hypothesis that insufficient selenium concentration may be a contributing factor to the pathophysiological mechanisms associated with preeclampsia, and optimizing the dietary selenium intake through supplementation could produce demonstrable clinical benefits.  相似文献   
92.
Lethal and sublethal effects of spirotetramat, spiromesifen and spirodiclofen were assessed on Tetranychus urticae Koch. Leaf disc bioassay was used in all experiments. In this study, toxicity of these compounds was tested on T. urticae eggs and adults. Ovicidal activity was observed in all of the compounds tested, but only spirodiclofen was considerably effective against adult mites. Up to 24?h-old adult females were placed on leaf discs treated with sublethal concentrations (LC10 or LC25). Twenty-four hours after exposure to treated discs, 20 females showing no visible symptoms of poisoning were transferred to untreated leaf discs. The leaf discs were changed daily for up to five days. The number of eggs laid during this period was recorded. The survival rate, total number of laid eggs per female and egg hatching rate were calculated. All above-mentioned parameters were slightly lower in treated females compared with controls.  相似文献   
93.
Moskovitz J  Maiti P  Lopes DH  Oien DB  Attar A  Liu T  Mittal S  Hayes J  Bitan G 《Biochemistry》2011,50(49):10687-10697
Self-assembly of amyloid β-protein (Aβ) into toxic oligomers and fibrillar polymers is believed to cause Alzheimer's disease (AD). In the AD brain, a high percentage of Aβ contains Met-sulfoxide at position 35, though the role this modification plays in AD is not clear. Oxidation of Met(35) to sulfoxide has been reported to decrease the extent of Aβ assembly and neurotoxicity, whereas surprisingly, oxidation of Met(35) to sulfone yields a toxicity similar to that of unoxidized Aβ. We hypothesized that the lower toxicity of Aβ-sulfoxide might result not only from structural alteration of the C-terminal region but also from activation of methionine-sulfoxide reductase (Msr), an important component of the cellular antioxidant system. Supporting this hypothesis, we found that the low toxicity of Aβ-sulfoxide correlated with induction of Msr activity. In agreement with these observations, in MsrA(-/-) mice the difference in toxicity between native Aβ and Aβ-sulfoxide was essentially eliminated. Subsequently, we found that treatment with N-acetyl-Met-sulfoxide could induce Msr activity and protect neuronal cells from Aβ toxicity. In addition, we measured Msr activity in a double-transgenic mouse model of AD and found that it was increased significantly relative to that of nontransgenic mice. Immunization with a novel Met-sulfoxide-rich antigen for 6 months led to antibody production, decreased Msr activity, and lowered hippocampal plaque burden. The data suggest an important neuroprotective role for the Msr system in the AD brain, which may lead to development of new therapeutic approaches for AD.  相似文献   
94.
The morphometric characteristics of the European Pond Turtle, Emys orbicularis, were studied at Anzali lagoon on the southern coast of the Caspian Sea. Males were on average (N=249) with 272.0?g significantly lighter than females with 447.0?g, and average carapace length was significantly smaller (123.0?mm in males, 139.0 in females). Females exceeded males also in all other studied characters (carapace width, plastron length, plastron width, and scute height). The sex ratio of male to female was 1 to 1.03, and the comparison of total tail length and cloaca-tail tip length revealed a difference between the position of the cloaca in both sexes, a character useful for sex determination in this species.  相似文献   
95.
Molecular Biology Reports - Bone regeneration is a significant and crucial health issue worldwide. Tissue bioengineering has shown itself to be the best substitute for common clinical treatment of...  相似文献   
96.
Membrane fusion underlies such important biological processes as virus entry into host cells, intracellular protein trafficking, fertilization, formation of muscle fibres and bone resorption. In addition, pathologies such as osteoporosis and implant rejection have been attributed to aberrant fusion. Members of the tetraspanin protein superfamily have been ascribed multiple roles in membrane biology, forming extensive lateral associations and regulating the function of effector molecules by clustering them in specific areas of the membrane. The present review aims to summarize the experimental evidence for tetraspanin function in different fusion events and highlight common themes.  相似文献   
97.
Fourteen heat resistant mutant strains were isolated from a wild-type strain (PP201, Nod+ Fix+) of Rhizobium sp. (Cajanus) by giving it a heat shock of 43°C. These mutant strains showed a greater increase in optical density (O.D.) and a higher viable cell count in both rhizospheric and non-rhizospheric soil at high temperature. Symbiotic studies showed that pigeon pea plants inoculated with a few mutant strains had ineffective nodules (Nod+ Fix) under controlled temperature (43°C) conditions, but under natural high temperature (40–45°C) conditions, the host plants infected with all the mutant strains showed higher total shoot nitrogen than the plants inoculated with the parent strain. Four mutant strains (HR-3, HR-6, HR-10 and HR-12) were found to be highly efficient for all the symbiotic parameters, and thus have the potential to be used as bioinoculants in the North-Western regions of India during the summer season.  相似文献   
98.
BioMetals - A cadmium(II) complex containing dppt ligand with the formula [CdCl2(dppt)2], where dppt is 5,6-diphenyl-3-(2-pyridyl)-1,2,4-triazine was synthesized, elucidated and submitted to in...  相似文献   
99.
Multiple sclerosis (MS) is a type of inflammatory and demyelinating disorder of the central nervous system in which immune-mediated inflammatory processes are elicited by secreted cytokines from T helper (Th)-1 and Th17 cells. While some protein-coding genes expressed in T cell types have established involvement in MS disease progression, little is understood about the roles of long noncoding RNAs (lncRNAs) within the disease landscape. LncRNAs, noncoding RNAs longer than 200 nucleotides, likely control gene expression and function of Th1 cells, and offer the potential to act as therapeutic and biomarker candidates for MS. We identified lncRNAs in Th1 cells linked to MS. Expression levels of candidate lncRNAs and genes were evaluated in 50 MS patients and 25 healthy controls using quantitative real-time polymerase chain reaction, and their correlations were assessed. LncRNAs encoded by AC007278.2 and IFNG-AS1-001 showed significantly higher expression in relapsing Phase MS patients whereas IFNG-AS1-003 was elevated in patients in the remitting phase compared with relapsing patients. Collectively, these misregulated lncRNAs may provide valuable tools to understand the relationships between lncRNAs and MS, and possibly other related disorders.  相似文献   
100.
Cervical cancer is among the most common type of cancers in women and is associated with human papillomavirus (HPV) infection. Genital warts are also reported to be linked with HPV infection types 11 and 6. In turn, clinical characteristics and morphological features of warts may be useful in the prediction of prognosis and in making treatment decisions. Thus, we have investigated the association of high and low-risk HPVs genotype with genital wart risk, as well as pathological and cytological information in cases recruited from a population-based cohort study of 1380 patients. Patients infected with HPV genotype 6 or 11 had an increased risk of having warts, with OR of 2.34 (95% CI: 0.955-5.737, P = 0.06). Also, this association was enhanced in the presence of high plus low-risk HPV for having genital wart (OR: 2.814; 95%: 1.208-6.55, P = 0.017) and cases having high-risk HPV (OR: 2.329; 95% CI: 1.029-5.269, P = 0.042). Moreover, we observed patients with genital warts having CIN2/3, indicating the importance of informing the physician to the patient to prevent more severe lesions. Our data demonstrated that patients with both low/high-risk HPV types had an increased risk of developing genital warts and persistent infection with HPV was a necessary precursor for the increase in cervical lesions.  相似文献   
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