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91.
Selective MSCs differentiation protocol into pancreatic beta cells was conducted in the present study using exendin-4 and TGF-beta. Differentiated and undifferentiated MSCs were assessed in experimental type I diabetes in rats. Ninety female white albino rats were included in the study and divided equally (n=15/group) into 6 groups: healthy control, healthy control rats received acellular tissue culture medium, diabetic rats, diabetic rats received acellular tissue culture medium, diabetic rats received undifferentiated MSCs and diabetic rats received differentiated MSCs. Therapeutic efficacy of undifferentiated versus differentiated MSCs was evaluated via assessment of quantitative gene expressions of insulin1, insulin 2, Smad-2, Smad-3, PDX-1, PAX-4, neuroD. Blood glucose and insulin hormone levels were also assessed. Results showed that quantitative gene expressions of all studied genes showed significant decrease in diabetic rat groups. Use of undifferentiated and differentiated MSCs led to a significant elevation of expression levels of all genes with more superior effect with differentiated MSCs except smad-2 gene. As regards insulin hormone levels, use of either undifferentiated or differentiated MSCs led to a significant elevation of its levels with more therapeutic effect with differentiated MSCs. Blood glucose levels were significantly decreased with both undifferentiated and differentiated MSCs in comparison to diabetic groups but its levels were normalized 2 months after injection of differentiated MSCs. In conclusion, use of undifferentiated or differentiated MSCs exhibited significant therapeutic potentials in experimental type I diabetes in rats with more significant therapeutic effect with the use of differentiated MSCs.  相似文献   
92.
93.
Adaptive evolution of G-protein coupled receptor genes   总被引:2,自引:0,他引:2  
The phylogeny and patterns of nucleotide substitutions in the visual pigment genes, adrenergic receptor genes, muscarinic receptor genes, and in the human mas oncogene were studied by comparing their DNA sequences. The evolutionary tree obtained shows that the visual pigment genes and mas oncogene form one cluster and that the receptor genes form another. In the evolution of rhodopsin genes, synonymous substitutions outnumber nonsynonymous substitutions. This is consistent with the neutral theory of molecular evolution. However, the early evolutionary stages of alpha- and beta-adrenergic and muscarinic receptors are notable for significantly more nonsynonymous substitutions than synonymous substitutions, suggesting the acquisition of novel functional adaptations. Variable rates of nonsynonymous changes in different domains of these proteins reveal DNA segments that might have been important in their functional adaptations.   相似文献   
94.
Eutypine, 4-hydroxy-3-(3-methyl-3-butene-1-ynyl) benzaldehyde, is a toxin produced by Eutypa lata, the causal agent of Eutypa dieback in grapevine. The effect of the toxin on anthocyanin synthesis has been investigated in Vitis vinifera cv. Gamay cell cultures. At concentrations higher than 200 micromol/L, eutypine reduced anthocyanin accumulation in cells. The reduction in anthocyanin accumulation was proportional to the eutypine concentrations and HPLC analysis showed that eutypine affected the levels of all anthocyanins. The effect of eutypine application on the expression of five genes of the anthocyanin biosynthesis pathway, including chalcone synthase (CHS), flavonone-3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), leucoanthocyanidin dioxygenase (LDOX), and UDP glucose-flavonoid 3-O-glucosyl transferase (UFGT) was determined. Expression of CHS, F3H, DFR and LDOXwas not affected by the addition of eutypine to grapevine cell cultures. In contrast, expression of the UFGT gene was dramatically inhibited by the toxin. These results suggest that in grapevine cell cultures, eutypine strongly affects anthocyanin accumulation by inhibiting UFGT gene expression. The mechanism of action of eutypine is discussed.  相似文献   
95.

Background:

Nationally representative Canadian data on the prevalence of child abuse and its relation with mental disorders are lacking. We used contemporary, nationally representative data to examine the prevalence of 3 types of child abuse (physical abuse, sexual abuse and exposure to intimate partner violence) and their association with 14 mental conditions, including suicidal ideation and suicide attempts.

Methods:

We obtained data from the 2012 Canadian Community Health Survey: Mental Health, collected from the 10 provinces. Respondents aged 18 years and older were asked about child abuse and were selected for the study sample (n = 23 395). The survey had a multistage stratified cluster design (household response rate 79.8%).

Results:

The prevalence of any child abuse was 32% (individual types ranged from 8% to 26%). All types of child abuse were associated with all mental conditions, including suicidal ideation and suicide attempts, after adjustment for sociodemographic variables (adjusted odds ratios ranged from 1.4 to 7.9). We found a dose–response relation, with increasing number of abuse types experienced corresponding with greater odds of mental conditions. Associations between child abuse and attention deficit disorder, suicidal ideation and suicide attempts showed stronger effects for women than men.

Interpretation:

We found robust associations between child abuse and mental conditions. Health care providers, especially those assessing patients with mental health problems, need to be aware of the relation between specific types of child abuse and certain mental conditions. Success in preventing child abuse could lead to reductions in the prevalence of mental disorders, suicidal ideation and suicide attempts.Child abuse is a major public health problem worldwide with serious adverse effects at later ages. The best estimates of the prevalence of child abuse in Canada come from 2 representative samples from Ontario, 1 from 1990 (Ontario Health Supplement, n = 9953, age ≥ 15 yr)1 and 1 from 2000–2001 (Ontario Child Health Study, n = 1893, age 21–35 yr).2 The 1990 study indicated that 31% of males and 21% of females had experienced physical child abuse, and 4% of males and 13% of females had experienced sexual child abuse.1 Similar trends were noted in data collected in 2000–2001.2 Prevalence of sexual abuse was found to be higher in the Ontario Child Health Study, but this was thought to be related to the inclusion of sexual abuse committed by anyone (e.g., adolescents), rather than only adults, as was the case with the Ontario Health Supplement.1,2 Data from Quebec collected in 2006 indicated that 23% of men and 17% of women had experienced physical child abuse; 10% of men and 22% of women had experienced sexual child abuse; and 22% of men and women had experienced psychological child abuse, including exposure to intimate partner violence.3,4 Unfortunately, these estimates are dated, restricted to only 2 provinces, based on limited assessments of child abuse and, in the case of the Quebec data, involve a low response rate of 30%.Although the association between child abuse and subsequent mental conditions (including disorders, suicidal ideation and suicide attempts) is well established,59 we know little about differential effects associated with several abuse types and specific mental disorders, and we currently have no nationally representative Canadian data. Filling this gap in knowledge would produce evidence-based Canadian findings that could inform policy, prevention and intervention efforts specifically aimed at reducing both child abuse and poor mental health outcomes.Our overall objective was to extend our understanding of the relation between child abuse and mental conditions (i.e., mental disorders, suicidal ideation and suicide attempts)68,1019 with a more detailed examination of child abuse severity and mental health outcomes. We used a nationally representative Canadian sample to examine 3 types of child abuse (physical abuse, sexual abuse and exposure to intimate partner violence) and 14 mental conditions, including suicidal ideation and suicide attempts. The specific research objectives were to estimate the prevalence of 3 types of physical abuse, sexual abuse and exposure to intimate partner violence; to examine the association of mental conditions with types of child abuse and number of child abuse types experienced; and to determine whether sex differences exist in the associations between child abuse and mental conditions.  相似文献   
96.
This study was carried out to determine the LC50 of zinc oxide nanoparticles (ZnONPs) on Oreochromis niloticus and to investigate the effect of vitamin E and C on hematological and biochemical alterations induced by two sublethal concentrations (1 and 2 mg/L) of ZnONPs. One hundred and eighty fish were used for studying the lethal concentrations of ZnONPs. For sublethal study two hundred and twenty-five males of O. niloticus were equally divided into five groups, control, the second and the third were treated with 1 and 2 mg/L ZnONPs respectively. The fourth and fifth were exposed to the same concentrations of ZnONPs plus vitamins E and C. The results revealed that the 96 h LC50 of ZnONPs was 3.1 ± 0.4 mg/L. The sublethal study revealed the presence of normocytic normochromic anemia in groups (2, 3 and 5) along the experiment period. The 4th group showed normocytic normochromic anemia at the 7th day and microcytic hypochromic anemia at the 15th day. Leukocytosis, heterophilia, lymphopenia and monocytopenia were recorded at the 7th day in all treated groups compared with the normal control. At the 15th day heteropenia, lymphopenia and monocytopenia were reported in all treated groups. A significant increase in the serum levels of alkaline phosphatase, aminotransferases, urea, creatinine and erythrocytic nuclear and morphological abnormalities along the experimental periods in all treated groups compared with the normal control. Serum total protein and albumin levels were significantly decreased at the same period in the same groups. Addition of vitamin E and C to the diet (groups 4 and 5) significantly improved all measured parameters compared with groups (2 and 3) which treated with ZnONPs only.  相似文献   
97.
A. terreus isolates isolated from some bakery products, corn and rice were found to be able to produce territrems. 90% of theA. terreus isolated from bakery products were able to produce territrem A, with a mean of 0.09 ppm, while 80% ofA. terreus isolates produce territrem B with a mean of 0.24 ppm. On the other hand 31.8% of the isolates ofA. terreus from corn were able to produce territrem A with a mean of 0.44 ppm. ConcerningA. terreus isolates from rice, 66.7% were found to produce territrem A, with a mean of 5.28 ppm, and 77.8% of the isolates produced territrem B with a mean of 1.79 ppm.  相似文献   
98.
It is common practice to study jump landing mechanics by having subjects step off a box set at a certain height instead of landing from a jump. This practice assumes that the landing mechanics are similar between stepping off a box and a countermovement jump as long as the heights can be matched. The mechanics of the two methods had never been compared when landing from identical heights. Thus, the purpose of this study was to compare the mechanics of landing from a countermovement jump to landing from a step-off. Participants performed three maximal countermovement jumps. The mechanics of one countermovement jump was compared with a center of mass fall height matched step-off landing. The step-off landing showed a more rapid time to peak ground reaction force (GRF) in both genders and greater GRF peak and loading rate in males only. No difference was observed between joint angles at initial contact; however, the countermovement jump showed significantly greater joint flexion angles at peak GRF for both genders. EMG showed greater muscle activity during the countermovement jump condition in all subjects. It was concluded that countermovement jump landings are different from step-off landings; thus, results from analyses involving step-off landings should be taken with caution if the aim is to relate them to landing from a jump.  相似文献   
99.
Microbial transformation of glabratephrin, the major isolated compound from Tephrosia purpurea, afforded pseudosemiglabrin. The formation of the transformed compound seems to be performed via ring opening-closure of a five-membered ring causing transformation from a spiro into a fused system. The structure of the transformed compound was determined by comprehensive NMR studies, including DEPT, COSY, HMQC, NOE and MS.  相似文献   
100.
The leaves and unripe and fully‐grown fruits of Schinus molle were collected from three geographical regions of Jordan: Amman (the Mediterranean), Madaba (Irano‐Turanean), and Sahab (Saharo‐Arabian). The hydrodistilled volatile oils of fresh and dried leaves and fruits were analyzed by gas chromatography‐mass spectrometry (GC/MS). The actual composition of the emitted volatiles was determined using Solid Phase Micro‐Extraction (SPME). α‐ and β‐Phellandrenes were the major components in all the analyzed samples. Quantitative differences were observed in the obtained essential oils (0.62–5.25 %). Additionally, cluster analysis was performed. Biologically, the antiproliferative activity of the essential oil, ethanol, and water extracts of the fruits and leaves was screened on Caco2, HCT116, MCF7, and T47D cell lines. The essential oil and ethanol extracts exhibited a dose‐dependent inhibition of cell growth with IC50 ranging between 21 and 65 μg/mL. The water extract did not exhibit any antiproliferative activity against the investigated cell lines.  相似文献   
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