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71.
IntroductionPolio, which is caused by poliovirus, is a contagious, potentially crippling, and deadly disease. Pakistan is one of the countries in which polio is still endemic in the 21st century. In 2019, 146 polio cases were reported across the country with some resulting in deaths. Following the spread of rumors insinuating that children were falling sick after receiving an anti-polio vaccine, a mob attacked and set fire to a small hospital in the Peshawar district in April 2019. The present study investigates readers’ discussions that emerged from Dawn’s online readers’ comments on polio-related news stories in Pakistan.MethodsUsing thematic analysis, we analyzed (N = 2216) comments made by readers in the polio-related news stories published on Dawn.com from January 1, 2012, to March 1, 2020.ResultsSeven major themes emerged from the analysis of the comments: 1) reasons for and challenges resulting in the failure to eradicate polio; 2) proposed solutions and policy changes to eradicate polio; 3) misinformation; 4) criticism, frustration, and shame; 5) comparison of Pakistan to other countries; 6) the internet as a public sphere; 7) suffering, empathy, and appreciation. Overall, our findings suggested that commenters are knowledgeable about polio vaccines and consider polio a serious threat to public health in Pakistan.ConclusionOur study not only validated previous study findings such as reasons, challenges, and issues related to polio vaccination, but also found new challenges in online news sites concerning misinformation on polio and polio vaccination in Pakistan.  相似文献   
72.
Journal of Public Health - Iranian New Year, with long consecutive holidays, although it is celebrated and enjoyed, might influence the quality of services provided by hospitals. The present study...  相似文献   
73.
This paper highlights a series of studies using the male rhesus monkey that has led to a model for the control of the onset of puberty in higher primates. The model proposes that the timing of puberty in these species is governed by the duration of a central brake that, during juvenile development, holds in check the hypothalamic network of gonadotropin-releasing hormone (GnRH) neurons, which, in the adult, drive the pituitary-gonadal axis. The neurobiology of this hypothalamic brake, and the physiological mechanisms that time its application and removal, are incompletely understood. Nevertheless, the pubertal resurgence of pulsatile GnRH release, which terminates the juvenile phase of primate development and triggers the initiation of puberty in man and monkeys, is associated with structural and molecular remodeling of the hypothalamus. A major component of this developmental plasticity appears to involve neuropeptide Y (NPY). NPY inhibits GnRH release, and NPY gene expression in the hypothalamus is elevated during juvenile development when GnRH release is restrained. Since the changes in hypothalamic function and morphology that trigger primate puberty unfold in the absence of gonadal steroid feedback, the possibility is raised that, in addition to activating the pituitary-gonadal axis at this stage of development, they may also contribute directly to the causation of behaviors and affective states that emerge at adolescence.  相似文献   
74.
To obtain a better understanding of the biology behind life-threatening fungal infections caused by Candida albicans, we recently conducted an in silico screening for fungal and host protein interaction partners. We report here that the extracellular domain of human CD4 binds to the moonlighting protein enolase 1 (Eno1) of C. albicans as predicted bioinformatically. By using different anti-CD4 monoclonal antibodies, we determined that C. albicans Eno1 (CaEno1) primarily binds to the extracellular domain 3 of CD4. Functionally, we observed that CaEno1 binding to CD4 activated lymphocyte-specific protein tyrosine kinase (LCK), which was also the case for anti-CD4 monoclonal antibodies tested in parallel. CaEno1 binding to naïve human CD4+ T cells skewed cytokine secretion toward a Th2 profile indicative of poor fungal control. Moreover, CaEno1 inhibited human memory CD4+ T-cell recall responses. Therapeutically, CD4+ T cells transduced with a p41/Crf1-specific T-cell receptor developed for adoptive T-cell therapy were not inhibited by CaEno1 in vitro. Together, the interaction of human CD4+ T cells with CaEno1 modulated host CD4+ T-cell responses in favor of the fungus. Thus, CaEno1 mediates not only immune evasion through its interference with complement regulators but also through the direct modulation of CD4+ T-cell responses.  相似文献   
75.
Ethanolic extract ofDaucus carota (DC) at the dose of 10–100 mg/kg caused a dose-dependent fall in systolic and diastolic arterial, blood pressure in normotensive anesthetized rats. These effects were not blocked by atropine (1 mg/kg) and pretreatment withDC did not alter the pressor response to norepinephrine indicating that, cardiovascular effects ofDC are independent of cholinergic or adrenergic receptors involvement. In spontaneously beating guinea-pig paired atria,DC induced a, concentration-dependent (0.3–5 mg/ml) decrease in force and rate of atrial contractions. In rabbit thoracic aorta,DC caused inhibition of K+-induced contractions at similar concentrations. These results suggest that the extract may exhibit Ca2+ channel blocking-like direct relaxant action on cardiac and smooth muscle preparations and this action may be responsible for its hypotensive effect observed in thein vivo studies.  相似文献   
76.
OBJECTIVE: To determine (i) the cost issues which Saudi health care managers perceive to influence overall quality improvement initiatives, and (ii) the relationship between health care managers' satisfaction with such initiatives and their perceptions regarding the influence of different cost issues on the overall quality improvement initiatives. DESIGN: Data were collected through a self-administered questionnaire in August and September 1996 in the Western Region of the Kingdom of Saudi Arabia. The participants were 236 health care managers of private hospitals. Data was analysed using the chi2 test. RESULTS: Less than one-half of the health care managers surveyed were satisfied with their hospitals' overall quality improvement initiatives. The issue that was rated to have the most influence on such initiatives was the 'cost of malpractice lawsuits' followed by the budget for the quality assurance programme'. The issue that was perceived to have the least influence on overall quality improvement initiatives was 'data on cost allocation'. Of the 17 cost issues included in the study, eight had statistically significant influence on the health care managers' satisfaction with their hospitals' overall quality improvement initiatives. The most statistically significant was the 'measurement of the costs of quality-related actions'.  相似文献   
77.
Urine contains several macromolecules that inhibit calcium oxalate (CaOx) crystallization. Among them is bikunin, the light chain of most of the inter-α-inhibitor (IαI) family of glycoproteins. This study aimed to verify whether bikunin and other members of the IαI family are synthesized in the kidneys or derived exclusively from the plasma. Proteins extracted from homogenized bovine kidney were applied successively to three chromatographic steps on DEAE-Sephacel, Sephacryl S-300, and Mono Q column. The inhibitory activity was assayed using a CaOx crystallization system. The presence of IαI-related proteins was determined by␣electrophoresis and Western blotting. The results showed that kidney extract contained a 125-kDa protein that cross-reacted with anti-IαI antibodies. This protein inhibited CaOx crystallization efficiently. According to its molecular weight and immunoreaction with anti-IαI antibody, the 125-kDa protein could be pre-α-inhibitor. The latter is known to encompass a heavy chain and bikunin, which may explain its inhibitory activity against CaOx crystallization. Consequently, we hypothesize that kidneys may produce some IαI-related proteins that are involved in the inhibition of stone formation. Received: 18 February 1998 / Accepted: 9 July 1998  相似文献   
78.
The synthesis and evaluation of analogues of previously reported farnesyltransferase inhibitors, pyridyl benzyl ether 3 and pyridylbenzylamine 4, are described. Substitution of 3 at the 5-position of the core aryl ring resulted in inhibitors of equal or less potency against the enzyme and decreased efficacy in a cellular assay against Ras processing by the enzyme. Substitution of 4 at the benzyl nitrogen yielded 26, which showed improved efficacy and potency and yet presented a poor pharmacokinetic profile. Further modification afforded 30, which demonstrated a dramatically improved pharmacokinetic profile. Compounds 26 and 29 demonstrated significant in vivo efficacy in nude mice inoculated with MiaPaCa-2, a human pancreatic tumor-derived cell line.  相似文献   
79.
The purpose of this study was to investigate the medium-term effects of methotrexate (MTX) and indomethacin on the growth of young rats. Four equal groups of Sprague-Dawley male rats (four animals in each group; mean+/-S.D. body weight, 183+/-13 g, in their rapid growth phase) were subjected to the following drug treatment: one group was given MTX (0.2 mg kg(-1) body weight) subcutaneously on every fourth day, another received indomethacin (2.5 mg kg(-1) body weight) subcutaneously daily and the third group was given both of these drugs (MTX on every fourth day and indomethacin daily). The fourth group was injected subcutaneously with physiological saline every day to serve as a control group. Total body weight, food and water consumption by animals in each group were monitored every second day for a period of 10 weeks. After this period, liver, spleen and kidneys were excised, weighed and analysed for MTX and dihydrofolate reductase activity. Compared with the groups, which received MTX alone, indomethacin alone, or physiological saline, mean increase (17+/-11 g) in body weight of rats was minimal in the group receiving both MTX and indomethacin. The difference was statistically significant (p=0.001) when the values of mean increase in body weight of rats in different treatment groups after a 10-week treatment were compared. The mean weights of liver and spleen in this group receiving both MTX and indomethacin were also found to be significantly less than the weights of these organs in the control group (p<0.01). There also appears to be a decline in food consumption in this group (p<0.05). This negative effect on growth of animals in this group appears to be not only due to decreased food consumption but also due to increased inhibition of de novo pathway of DNA synthesis. This is supported by increased accumulation of MTX and decreased dihydrofolate reductase activity in this group receiving both MTX and indomethacin, as compared with the group receiving MTX alone. The data indicate an additive effect of MTX and indomethacin on the suppression of growth in young rats, alluding to the notion that patients suffering from juvenile rheumatoid arthritis or acute lymphoblastic leukaemia receiving these two drugs concomitantly over a long period of time might be at a risk of experiencing short-term suppression of growth.  相似文献   
80.

Objectives

To compare the incidence and severity of acetabular fractures and associated injuries before and after seatbelt legislation.

Design

A retrospective study.

Setting

Two major trauma centres, which are teaching hospitals.

Patients

Three hundred and ninety-three patients who sustained acetabular fractures during the 5 years before and 5 years after seatbelt legislation was enacted. Of these, the fractures in 198 patients (50.4%) resulted from a motor vehicle accident.

Main Outcome Measures

The number and severity of acetabular fractures and associated injuries.

Results

There has been a significant reduction in the number of acetabular fractures (p = 0.005) since seatbelt use became mandatory, and the complexity of the fractures has decreased. There has also been a marked reduction in associated injuries, such as fractures of other bones, and head, chest and abdominal injuries (p < 0.001).

Conclusion

The seatbelt law has been a useful preventive measure, resulting in a reduction in the incidence of acetabular fractures and associated injuries.  相似文献   
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