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31.
One of the key issues of current radiation research is the biological effect of low doses. Unfortunately, low dose science is hampered by the unavailability of easily performable, reliable and sensitive quantitative biomarkers suitable detecting low frequency alterations in irradiated cells. We applied a quantitative real time polymerase chain reaction (qRT-PCR) based protocol detecting common deletions (CD) in the mitochondrial genome to assess direct and non-targeted effects of radiation in human fibroblasts. In directly irradiated (IR) cells CD increased with dose and was higher in radiosensitive cells. Investigating conditioned medium-mediated bystander effects we demonstrated that low and high (0.1 and 2Gy) doses induced similar levels of bystander responses and found individual differences in human fibroblasts. The bystander response was not related to the radiosensitivity of the cells. The importance of signal sending donor and signal receiving target cells was investigated by placing conditioned medium from a bystander response positive cell line (F11-hTERT) to bystander negative cells (S1-hTERT) and vice versa. The data indicated that signal sending cells are more important in the medium-mediated bystander effect than recipients. Finally, we followed long term effects in immortalized radiation sensitive (S1-hTERT) and normal (F11-hTERT) fibroblasts up to 63 days after IR. In F11-hTERT cells CD level was increased until 35 days after IR then reduced back to control level by day 49. In S1-hTERT cells the increased CD level was also normalized by day 42, however a second wave of increased CD incidence appeared by day 49 which was maintained up to day 63 after IR. This second CD wave might be the indication of radiation-induced instability in the mitochondrial genome of S1-hTERT cells. The data demonstrated that measuring CD in mtDNA by qRT-PCR is a reliable and sensitive biomarker to estimate radiation-induced direct and non-targeted effects.  相似文献   
32.
Qidwai W  Ishaque S  Shah S  Rahim M 《PloS one》2010,5(9):e12914

Introduction

Adolescents form two-thirds of our population. This is a unique group of people with special needs. Our survey aims to identify the lifestyle and behavioral patterns in this group of people and subsequently come up with issues that warrant special attention.

Methods

A survey was performed in various schools of Karachi. Data collection was done via a face-to-face interview based on a structured, pre-tested questionnaire. Participants included all willing persons between 12–19 years of age.

Results

Most adolescents with lifestyle issues fell in the age group of 16–18 years. Females were more depressed than males and had more sleep problems. Substance abuse and other addictions were documented more in males. Watching television or listening to music was stated as the most common late night activity (61.8%) and therefore was also referred to as the contributory factor for less than eight hours of sleep each day. (58.9%) of the respondents are getting less than eight hours of sleep daily. (41.5%) of the respondents who felt depressed sought treatment for it. Quite a few of them were also indulged in substance abuse and other addictions. Only (16.8%) of the respondents opined that physical activity is essential for health. Thirty-five adolescents out of all the respondents were smoking cigarettes currently, whereas 7% of the respondents chewed paan (areca nut). Peer pressure was the most common reason (37.1%) to start smoking.

Conclusion

Adolescents need to be treated as a distinct segment of our population and it is important to realize and address their health and lifestyle problems. Inadequate sleep, depression and smoking were the leading unhealthy behaviours among the respondents. Families can play an important role to help these adolescents live a healthier life. Further research studies should be carried out to highlight issues of concern and their possible solutions in this population.  相似文献   
33.
BackgroundAcne is an inflammatory condition principally affected by genetic and dietary factors. Investigation into functional polymorphisms of TNF-α gene and their association with acne vulgaris will be helpful in exploring genetic influence on skin immune mediated inflammatory events. In the present study, we analyzed association of TNF-α gene polymorphisms, its expression levels and lipid profiles in a large cohort of acne patients and controls.MethodsWe used PCR-RFLP to study association of TNF-α polymorphisms at −857C/T, −863C/A and −1031 T/C sites with acne vulgaris. Lipid profiles were measured using enzymatic end-point method. The serum levels of TNF-α and apolipoprotein a were measured using ELISA. NIH, LDlink was used to investigate patterns of linkage disequilibrium across south Asian reference genome (Punjabi from Lahore Pakistan).ResultsWe found that TNF-α −863 polymorphism is strongly associated with acne in overall population as well as in gender and severity based groups of acne patients. Polymorphisms at −863 and −1031 position were in linkage disequilibrium. Importantly, TNF-α serum level was significantly increased in acne patients with severe disease symptoms. Furthermore, levels of total cholesterol (TC) and triglycerides (TG) were significantly increased, whereas high density lipoprotein cholesterol (HDL-C) level was significantly decreased in acne patients. The levels of apolipoprotein a varied widely in studied populations and no significant difference was found in the analyzed groups.ConclusionIn conclusion, we found that TNF-α expression increases in acne patients affected by TNF-α polymorphisms, and that the lipid profile is specifically disrupted in acne patients.  相似文献   
34.

Objective

To study frequency and associated factors for care giving among elderly patients visiting a teaching hospital in Karachi, Pakistan.

Methodology

A cross sectional questionnaire-based study was conducted at the Community Health Centre (CHC), Aga Khan University Hospital (AKUH) Karachi, Pakistan from September to November 2009. All individuals, visiting the CHC and aged 65 years or above were interviewed after taking written informed consent.

Results

A total of 400 elderly completed the interview. Majority were females, 65–69 years age, More than half of the individuals ie: 227 (85%) had received Care Giver experience for assistance and among these 195(72%) had care provided by an immediate family member. A large proportion of them stated that their Care Givers managed to provide less than four hours in a day for care giving. Around 37% showed substantial improvement in their relationship with the care givers. About 70% of the respondents stated that the care provided by the Care Giver improved their quality of life.

Conclusion

Elderly care is provided by majority of the family members resulting in increased satisfaction level, however small number still not satisfied due to unfulfilled need of these older people. This demands that efforts should be made to strengthen the family support by increasing awareness regarding elderly care and arranging support system by the government.  相似文献   
35.

Introduction

Violence against women is regarded as a major violation of human rights, and several socio-behavioral aspects among victims have been identified as important determinants of spousal violence experience. Pakistani nationally representative contextual evidence is scarce in this regard. We aimed to estimate prevalence of spousal violence, and explore its association with intergenerational transfer, and attitudinal acceptance of violence, among Pakistani ever-married women.

Materials and Methods

Data of 3,687 ever-married women from Pakistan Demographic and Health Survey, 2012-13 was used to perform secondary analysis. Logistic regression analyses were conducted. Association between the different forms of spousal violence and the independent variables: intergenerational transfer of spousal violence (mother also beaten up by father); and attitudinal acceptance of spousal violence (beating is justifies if wife argues with husband) were reported as Odds ratios with 95% confidence intervals (CI).

Results

Overall, more than a third (n=1344, 37.9%)of ever-married women reported that they experienced spousal violence. Almost 68% (n=539) of the women who reported that their mothers were also beaten up by their fathers, were victims of spousal violence; and almost 47% (n=603) of the women who agreed that beating was justified if the wife argues with her husband, also suffered spousal violence. Intergenerational transfer (OR =5.71, 95%CI 4.40-7.41, p-value <0.01), and attitudinal acceptance (OR =1.66, 95%CI 1.27-2.15, p-value <0.01) were significantly associated with experience of physical violence even after adjusting for respondents’ age at marriage, education level, wealth index, parity, employment status, and empowerment status.

Conclusions

Spousal violence continues to haunt the lives of women in Pakistan, and is being transmitted as a learned behavior from mothers to daughters who tend to accept such violation of human rights. Girl children from such unfortunate homes may continue to transmit such behaviors, and thus may be targeted for future anti-domestic violence efforts.  相似文献   
36.
Targeted therapy involving the activation of death receptors DR4 and/or DR5 by its ligand, TRAIL, can selectively induce apoptosis in certain tumor cells. In order to profile the dynamic activation or trimerization of TRAIL–DR4 in live cells in real‐time, the development of an apoptosis reporter cell line is essential. Fluorescence resonance energy transfer (FRET) technology via a FRET pair, cyan fluorescence protein (CFP) and yellow fluorescence protein (YFP), was used in this study. DR4‐CFP and DR4‐YFP were stably expressed in human lung cancer PC9 cells. Flow cytometer sorting and limited dilution coupled with fluorescence microscopy were used to select a monoclonal reporter cell line with high and compatible expression levels of DR4‐CFP and DR4‐YFP. FRET experiments were conducted and FRET efficiencies were monitored according to the Siegel's YFP photobleaching FRET protocol. Upon TRAIL induction a significant increase in FRET efficiencies from 5% to 9% demonstrated the ability of the DR4‐CFP/YFP reporter cell line in monitoring the dynamic activation of TRAIL pathways. 3D reconstructed confocal images of DR4‐CFP/YFP reporter cells exhibited a colocalized expression of DR4‐CFP and DR4‐YFP mainly on cell membranes. FRET results obtained during this study complements the use of epi‐fluorescence microscopy for FRET analysis. The real‐time FRET analysis allows the dynamic profiling of the activation of TRAIL pathways by using the time‐lapse fluorescence microscopy. Therefore, DR4‐CFP/YFP PC9 reporter cells along with FRET technology can be used as a tool for anti‐cancer drug screening to identify compounds that are capable of activating TRAIL pathways. Biotechnol. Bioeng. 2013; 110: 1396–1404. © 2012 Wiley Periodicals, Inc.  相似文献   
37.
We recently demonstrated that S-glutathionylation of the death receptor Fas (Fas-SSG) amplifies apoptosis (V. Anathy et al., J. Cell Biol. 184:241-252, 2009). In the present study, we demonstrate that distinct pools of Fas exist in cells. Upon ligation of surface Fas, a separate pool of latent Fas in the endoplasmic reticulum (ER) underwent rapid oxidative processing characterized by the loss of free sulfhydryl content (Fas-SH) and resultant increases in S-glutathionylation of Cys294, leading to increases of surface Fas. Stimulation with FasL rapidly induced associations of Fas with ERp57 and glutathione S-transferase π (GSTP), a protein disulfide isomerase and catalyst of S-glutathionylation, respectively, in the ER. Knockdown or inhibition of ERp57 and GSTP1 substantially decreased FasL-induced oxidative processing and S-glutathionylation of Fas, resulting in decreased death-inducing signaling complex formation and caspase activity and enhanced survival. Bleomycin-induced pulmonary fibrosis was accompanied by increased interactions between Fas-ERp57-GSTP1 and S-glutathionylation of Fas. Importantly, fibrosis was largely prevented following short interfering RNA-mediated ablation of ERp57 and GSTP. Collectively, these findings illuminate a regulatory switch, a ligand-initiated oxidative processing of latent Fas, that controls the strength of apoptosis.  相似文献   
38.

Background and Objective

Cervical cancer is one of the leading causes of morbidity and mortality amongst the gynecological cancers worldwide, especially in developing countries. It is imperative for at least health professionals in developing countries like Pakistan to have a sound knowledge about the disease. This study was carried out to assess the knowledge and awareness about cervical cancer and its prevention amongst health professionals in tertiary care hospitals in Karachi, Pakistan.

Methods and Design

A cross-sectional, interview based survey was conducted in June, 2009. Sample of 400 was divided between the three tertiary care centers. Convenience sampling was applied as no definitive data was available regarding the number of registered interns and nurses at each center.

Results

Of all the interviews conducted, 1.8% did not know cervical cancer as a disease. Only 23.3% of the respondents were aware that cervical cancer is the most common cause of gynecological cancers and 26% knew it is second in rank in mortality. Seventy-eight percent were aware that infection is the most common cause of cervical cancer, of these 62% said that virus is the cause and 61% of the respondents knew that the virus is Human Papilloma Virus (HPV). Majority recognized that it is sexually transmitted but only a minority (41%) knew that it can be detected by PCR. Only 26% of the study population was aware of one or more risk factors. Thirty seven percent recognized Pap smear as a screening test. In total only 37 out of 400 respondents were aware of the HPV vaccine.

Conclusion

This study serves to highlight that the majority of working health professionals are not adequately equipped with knowledge concerning cervical cancer. Continuing Medical Education program should be started at the hospital level along with conferences to spread knowledge about this disease.  相似文献   
39.
Environmental factors, such as drought, salinity, extreme temperature, ozone poisoning, metal toxicity etc., significantly affect crops. To study these factors and to design a possible remedy, biological experimental data concerning these crops requires the quantification of gene expression and comparative analyses at high throughput level. Development of microarrays is the platform to study the differential expression profiling of the targeted genes. This technology can be applied to gene expression studies, ranging from individual genes to whole genome level. It is now possible to perform the quantification of the differential expression of genes on a glass slide in a single experiment. This review documents recently published reports on the use of microarrays for the identification of genes in different plant species playing their role in different cellular networks under abiotic stresses. The regulation pattern of differentially-expressed genes, individually or in group form, may help us to study different pathways and functions at the cellular and molecular level. These studies can provide us with a lot of useful information to unravel the mystery of abiotic stresses in important crop plants.  相似文献   
40.
Occurrence of salt stress with the soil borne fungus Fusarium oxysporum f. sp. cepa (FOC) are potential threat to the crop yield. This investigation reports effect of the concurrent stresses (salinity and FOC) on morpho-physiological and yield attributes in onion. In vitro growth tests revealed proliferation of FOC biomass at different levels of salinity (2–8 dS m?1). A greenhouse pot experiment with the proposed levels of salinity (2.5, 3.5 and 4.5 dS m?1) in combination with FOC inoculation showed more drastic effect of combined stress on disease severity, plant growth and bulb as compared to the individual stress. In general, osmotic potential, total chlorophyll content, membrane stability index and total protein content of the leaf were decreased, while total phenolics were increased due to the given stress/s. Total sugar content decreased due to effect of the  individual stress of FOC, while it increased under the individual stress of salinity and in combination with FOC. FOC infection did not change activity of polyphenol oxidase (PPO), while it improved peroxidase (POX) and phenylalanine ammonia lyase (PAL) and decreased catalase (CAT) activity. Activities of POX and PPO increased, however PAL and CAT declined under individual as well as simultaneous stress of salinity ?and ?FOC. The research work concluded that FOC will be a more severe disease threat for onion cultivation in saline soils.  相似文献   
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