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41.
BACKGROUND: Duplicated collecting systems comprises renal units containing two pyelocalyceal systems associated with a single ureter or double ureters and is the most common upper tract anomaly. CASE: This report presents a rare entity: an adult woman who had giant hydroureter of upper-pole moiety of the duplex kidney, which was an incidental finding during cesarean section. Heminephroureterectomy was done containing 2 L of fluid. This case is the first of its kind during cesarean section. CONCLUSION: The cause of this unusually massive degree of dilatation of the upper-pole moiety of the duplicated collecting system is uncertain, but may have resulted from an error in the development or because of VUR. We suggest mandatory intraabdominal examination after delivering uterus while conducting a cesarean section.  相似文献   
42.
43.
The effectiveness of mask wearing at controlling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission has been unclear. While masks are known to substantially reduce disease transmission in healthcare settings [D. K. Chu et al., Lancet 395, 1973–1987 (2020); J. Howard et al., Proc. Natl. Acad. Sci. U.S.A. 118, e2014564118 (2021); Y. Cheng et al., Science eabg6296 (2021)], studies in community settings report inconsistent results [H. M. Ollila et al., medRxiv (2020); J. Brainard et al., Eurosurveillance 25, 2000725 (2020); T. Jefferson et al., Cochrane Database Syst. Rev. 11, CD006207 (2020)]. Most such studies focus on how masks impact transmission, by analyzing how effective government mask mandates are. However, we find that widespread voluntary mask wearing, and other data limitations, make mandate effectiveness a poor proxy for mask-wearing effectiveness. We directly analyze the effect of mask wearing on SARS-CoV-2 transmission, drawing on several datasets covering 92 regions on six continents, including the largest survey of wearing behavior (n= 20 million) [F. Kreuter et al., https://gisumd.github.io/COVID-19-API-Documentation (2020)]. Using a Bayesian hierarchical model, we estimate the effect of mask wearing on transmission, by linking reported wearing levels to reported cases in each region, while adjusting for mobility and nonpharmaceutical interventions (NPIs), such as bans on large gatherings. Our estimates imply that the mean observed level of mask wearing corresponds to a 19% decrease in the reproduction number R. We also assess the robustness of our results in 60 tests spanning 20 sensitivity analyses. In light of these results, policy makers can effectively reduce transmission by intervening to increase mask wearing.

Face masks are one of the most prominent interventions against COVID-19, with very high uptake in most countries (1). However, global mask wearing fell substantially in 2021, even in countries with low vaccination rates (Fig. 1). Given ongoing epidemics, establishing the effectiveness of mask wearing in community settings is critical. The following sections review past work on the effectiveness of mask wearing in different settings and at different scales.Open in a separate windowFig. 1.Reported mask wearing in countries with <40% of population fully vaccinated, as of 1 October 2021 [wearing from the UMD/Facebook survey (1); vaccinations from ref. 2]. The y axis is the proportion who reported that, over the last week, they wore masks most or all of the time in public spaces.In the context of healthcare, N95 masks (as defined by ref. 3) work well when worn properly by trained users—reducing transmission of coronaviruses including severe acute respiratory coronavirus syndrome 2 (SARS-CoV-2) by at least half (4, 5). Cheng et al. (6) find that ideal surgical masking (7, 8) of a noninfected person corresponds to a 65 to 75% reduction in their risk of COVID-19.However, the effect of mask wearing in small-scale community settings is more difficult to detect.In particular, four meta-analyses have summarized studies on respiratory infections, conducted in community settings (4, 911). They estimate mean decreases in infection risk between 4% and 15% for surgical masks, but with large uncertainty: Individual results ranged from a 7% increase in infection risk to a 61% decrease in infection risk. In addition, few of these studies are randomized controlled trials (RCTs), and those that are RCTs have considerable issues: Bungaard et al. (12) found a small, nonsignificant reduction in infection risk. Abaluck et al. (13), found a significant, 8.6% decrease in symptomatic seropositivity linked to mask wearing. However, limitations of the study included a requirement for unblinded participants to self-report symptoms before testing, use of an antibody test with a very low 5 d sensitivity, and unclear generalization from the specific context (rural villages in Bangladesh).We focus on the effects of mask wearing or mandates (i.e., legal requirements to wear a mask) on transmission in large connected populations. To study mask impacts on transmission, many studies use the timing of mask mandates as a proxy for sharp changes in the level of mask wearing. Some such studies have inferred limited or inconclusive effects in cross-country analyses (14) and within-country studies (15), while others find cross-country evidence that mask mandates and recommendations lead to decreased transmission and mortality (16, 17).Other analyses provide evidence for reduced case growth following subnational mandates within countries such as the United States (1820) and Germany (21). A potential explanation for the inconsistency and uncertainty of these results is that data on national mandate timing may be poorly suited for analyzing the effects of mask wearing on transmission.Epidemiological studies often use government mask mandates as a proxy for mask wearing. However, the existing literature on the relationship between mandates and actual levels of mask wearing has shown surprisingly weak effects. For example, studying US states, ref. 22 failed to find a statistically significant relationship between mandates and subsequent wearing, while other studies found postmandate increases in wearing of just 13% (23) and 23% (24). Betsch et al. (25) find a ∼40% increase in wearing after local mandates in Germany, but no other study finds a comparably large increase. Given that the link between mandates and wearing is surprisingly weak, it is likely that the link between mandates and transmission is difficult to detect. Three additional factors lead us to suspect that a link between mandates and transmission would be difficult to detect. First, introducing a mandate is a coarse, one-off event that necessarily loses signal by not tracking day-to-day changes in mask wearing. We also have fewer data on mandates: Less than half of the regions we study enforced any mandate during the study period. Second, past studies treat mandates as a binary on/off intervention that is fully implemented at a single point in time. However, modeling the effect of mandates as an instantaneous change in the reproduction number or mortality fails to capture changes in wearing behavior following the announcement of a mandate but before its enforcement (21). Nor does it account for gradual change in behavior after the implementation of a mandate. Finally, the circumstances of mandate policies are highly heterogeneous, both in terms of the preexisting level of voluntary wearing at the time of implementation and in terms of how exactly they are defined, enforced, and complied with. Consequently, averaging the international effect of mandates based on coarse data is unlikely to provide a useful summary of heterogeneous mandate effects. Importantly, these arguments point to the link between mandates and transmission being difficult to detect, not that it is absent.Because of these difficulties in studying the effect of mandates, we instead focus on estimating the effect of mask wearing on transmission, using a large (n = 19.97 million) global survey of self-reported mask wearing (1). Two other studies estimate mask effectiveness from self-reports: In their study of 24 countries, Aravindakshan et al. (26) use YouGov wearing data to infer an overall 3.9 to 10% relative decrease in case growth rate from whole population mask wearing. Rader et al. (22) study US states using a novel SurveyMonkey wearing dataset to infer a ∼10% decrease in transmission between the lowest and highest empirical quartiles of wearing (a 50 to 75% increase in wearing). Rader et al. use data limited to 12 US states during June–July 2020. Our data are richer: We study 56 countries on six continents, and our inferential analyses span May–September 2020.Our analysis goes further than past work in the quality of wearing data—100 times the sample size, with random sampling and poststratification—the geographical scope, the use of a semimechanistic infection model, the incorporation of uncertainty into epidemiological parameters, and the robustness of our results (59 sensitivity tests). See
TerminologyMeaning
Clinical settingsAny inpatient setting involving healthcare professionals. These include hospitals, doctor’s offices, and other inpatient clinics; this covers the place, and so includes cleaners and receptionists (and anyone else) who are in contact with patients in inpatient settings. It would not include, for example, administrators working in an office attached to a hospital, or paramedics attending at an emergency.
Community settingsAny setting outside clinical or residential settings, such as public areas, restaurants, and public transportation, as well as public and private indoor areas.
MaskAny face covering. Unless specified, this is broadly construed to include both cloth and surgical-grade masks and above. See also refs. 3 and 7.
Mask wearingAll community mask wearing: the proportion of people wearing masks in community settings.
Reported mask wearingThe quantity of self-reported wearing in the following sense: Over the last week, respondents wore a mask most or all of the time when in public spaces; a proxy.
MandateAs per OxCGRT, a legal requirement to wear a mask, in a (usually national) region, “in [at least] some specified shared spaces outside the home with other people present or some situations when social distancing [is] not possible.”
Epidemiological effectAn effect studied at a population level, measured in entire populations, rather than with data observed at the individual level.
NPIA policy implemented to prevent transmission, excluding pharmaceuticals such as vaccines and therapeutics. Examples include school and business closures, stay-at-home orders, and restrictions on gatherings.
Open in a separate window  相似文献   
44.
Diagnosing asthma and chronic obstructive pulmonary disease: Importance of pulmonary function testing     
Samir Gupta 《Canadian family physician Médecin de famille canadien》2022,68(6):441
  相似文献   
45.
Impact of COVID-19 lockdown on sleep quality of pharmacy students in UiTM Puncak Alam     
Mizaton Hazizul Hasan  Gamal AE Moustafa 《Saudi Pharmaceutical Journal》2022,30(10):1521-1526
Due to the COVID-19 pandemic, the closure of educational institutions was executed during the period of lockdown. This subsequently led to alterations in daily routines and emotional distress, particularly among university students, affecting their sleep quality resulting in disturbance of immune functioning and mood regulation. Hence, the present study aimed to measure students' sleep quality during the first few months of the lockdown period. This study is a cross-sectional, single-centred survey that was done by distributed electronic questionnaire. The e-questionnaire was divided into 4 sections that assessed socio-demographic characteristics, sleep quality, psychological state and engagement in physical activity. Exactly 248 valid responses were received, 82 % female students. Students with poor sleep quality were three times greater than those with good sleep quality. No association were found between physical activity and sleep quality. However, a significant positive relationship between sleep quality and psychological state was observed (p < 0.01). In conclusion, this study suggests that the majority of pharmacy students in UiTM Puncak Alam are poor sleepers and psychological distress negatively affects sleep quality but, is mainly due to stress. Thus, interventions such as stress management programs and mental health support can be taken by the faculty's management to overcome this problem.  相似文献   
46.
Seizure heralding functional recovery in a patient with apallic syndrome: A case report with retrospective-prospective observation     
Al-Adawi S  Burke DT  Mastronardi SE 《Epilepsy & behavior : E&B》2006,8(4):776-780
BACKGROUND: It has been suggested that there exists a close relationship between seizure discharges and functional recovery from brain injury, and that paroxysmal bombardment in late seizures may herald functional recovery or may "kick-start" recovery. CASE REPORT: We report the case of a 52-year-old patient who, following a subarachnoid hemorrhage and multiple surgeries, experienced discernible apallic syndrome of long duration. His hospitalization is well documented. The patient underwent protracted, intense rehabilitation, but he remained in this prolonged state of loss of consciousness and behavioral passivity until he experienced a series of periodic seizures. Widespread improvement in his cognitive and functional abilities coincided closely with the seizure activity. The literature on this topic is reviewed. CONCLUSION: This case confirms the close relationship between seizure discharges and functional recovery reported in preclinical literature.  相似文献   
47.
Study of Two Techniques for Midline Laparotomy Fascial Wound Closure     
Vipul Gurjar  B. M. Halvadia  R. P. Bharaney  Vicky Ajwani  S. M. Shah  Samir Rai  Mitesh Trivedi 《The Indian journal of surgery》2014,76(2):91-94
To study the results of two techniques, simple interrupted closure and continuous with intermittent Aberdeen knot technique for midline laparotomy fascial wound closure. A random selection of 200 midline laparotomy cases was done. In one group (group A) of 100 cases, midline fascial wound closure was done with continuous sutures with intermittent Aberdeen knot technique using Prolene No. 1 suture material. In the other group (group B) of 100 cases, closure was done with the technique of simple interrupted sutures with Prolene No.1 suture material. Comparison of both the techniques regarding preoperative status and postoperative complication such as incisional hernia, wound dehiscence, suture sinus formation, stitch granuloma, and chronic wound pain was done according to clinical examination and recorded in the pro forma prepared. In group A, postoperative complications were incisional hernia 3 %, wound dehiscence 4 %, and suture sinus formation 1 %. In group B, postoperative complication were incisional hernia 5 %, wound dehiscence 4 %, and suture sinus formation 1 %. All these complications were statistically insignificant, in both group comparisons. While the complication such as stitch granuloma 3 %, chronic wound pain 3 %, and wound infection 4 % in group A was significantly less than in group B where the complication of stitch granuloma was 12 %, chronic wound pain 13 %, and wound infection 13 % (P value 0.03, P value 0.018, and P value 0.048, respectively). Both the techniques, simple interrupted suture closure and continuous with intermittent Aberdeen knot closure for midline laparotomy fascial wounds, show a similar rate of postoperative complication such as incisional hernia, wound dehiscence, and suture sinus formation. But the continuous suturing with intermittent Aberdeen knot technique is a better option to prevent complications such as stitch granuloma, chronic wound pain, and wound infection, which are higher in the simple interrupted fascial wound closure technique.  相似文献   
48.
Escherichia coli tetracycline efflux determinants in relation to tetracycline residues in chicken     
Al-Bahry SN  Al-Mashani BM  Al-Ansari AS  Elshafie AE  Mahmoud IY 《Asian Pacific journal of tropical medicine》2013,6(9):718-722
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment.  相似文献   
49.
Re: Urinary TMPRSS2:ERG and PCA3 in an Active Surveillance Cohort: Results from a Baseline Analysis in the Canary Prostate Active Surveillance Study     
Samir S. Taneja  M.D. 《The Journal of urology》2013
  相似文献   
50.
Excitatory Synaptic Function and Plasticity is Persistently Altered in Ventral Tegmental Area Dopamine Neurons after Prenatal Ethanol Exposure     
Kathryn Hausknecht  Samir Haj-Dahmane  Ying-Ling Shen  Paul Vezina  Cynthia Dlugos  Roh-Yu Shen 《Neuropsychopharmacology》2015,40(4):893-905
Prenatal ethanol exposure (PE) is one of the developmental factors leading to increased addiction propensity (risk). However, the neuronal mechanisms underlying this effect remain unknown. We examined whether increased excitatory synaptic transmission in ventral tegmental area (VTA) dopamine (DA) neurons, which is associated with drug addiction, was impacted by PE. Pregnant rats were exposed to ethanol (0 or 6 g/kg/day) via intragastric intubation from gestational day 8–20. Amphetamine self-administration, whole-cell recordings, and electron microscopy were performed in male offspring between 2 and 12-week-old. The results showed enhanced amphetamine self-administration in PE animals. In PE animals, we observed a persistent augmentation in calcium-permeable AMPA receptor (CP-AMPAR) expression, indicated by increased rectification and reduced decay time of AMPAR-mediated excitatory postsynaptic currents (AMPAR-EPSCs), enhanced depression of AMPAR-EPSCs by NASPM (a selective CP-AMPAR antagonist), and increased GluA3 subunits in VTA DA neuron dendrites. Increased CP-AMPAR expression in PE animals led to enhanced excitatory synaptic strength and the induction of CP-AMPAR-dependent long-term potentiation (LTP), an anti-Hebbian form of LTP. These observations suggest that, in PE animals, increased excitatory synaptic strength in VTA DA neurons might be susceptible to further strengthening even in the absence of impulse flow. The PE-induced persistent increase in CP-AMPAR expression, the resulting enhancement in excitatory synaptic strength, and CP-AMPAR-dependent LTP are similar to effects observed after repeated exposure to drugs of abuse, conditions known to increase addiction risk. Therefore, these mechanisms could be important neuronal substrates underlying PE-induced enhancement in amphetamine self-administration and increased addiction risk in individuals with fetal alcohol spectrum disorders.  相似文献   
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