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31.
Background. Previous studies examining the early spread of COVID-19 have used influenza-like illnesses (ILIs) to determine the early spread of COVID-19. We used COVID-19 case definition to identify COVID-like symptoms (CLS) independently of other influenza-like illnesses (ILIs). Methods. Using data from Emergency Department (ED) visits at VA Medical Centers in CA, TX, and FL, we compared weekly rates of CLS, ILIs, and non-influenza ILIs encounters during five consecutive flu seasons (2015–2020) and estimated the risk of developing each illness during the first 23 weeks of the 2019–2020 season compared to previous seasons. Results. Patients with CLS were significantly more likely to visit the ED during the first 23 weeks of the 2019–2020 compared to prior seasons, while ED visits for influenza and non-influenza ILIs did not differ substantially. Adjusted CLS risk was significantly lower for all seasons relative to the 2019–2020 season: RR15–16 = 0.72, 0.75, 0.72; RR16–17 = 0.81, 0.77, 0.79; RR17–18 = 0.80, 0.89, 0.83; RR18–19 = 0.82, 0.96, 0.81, in CA, TX, and FL, respectively. Conclusions. The observed increase in ED visits for CLS indicates the likely spread of COVID-19 in the US earlier than previously reported. VA data could potentially help identify emerging infectious diseases and supplement existing syndromic surveillance systems.  相似文献   
32.
Control of organ size by cell proliferation and survival is a fundamental developmental process, and its deregulation leads to cancer. However, the molecular mechanism underlying organ size control remains elusive in vertebrates. In Drosophila, the Hippo (Hpo) signaling pathway controls organ size by both restricting cell growth and proliferation and promoting cell death. Here we investigated whether mammals also require the Hpo pathway to control organ size and adult tissue homeostasis. We found that Mst1 and Mst2, the two mouse homologs of the Drosophila Hpo, control the sizes of some, but not all organs, in mice, and Mst1 and Mst2 act as tumor suppressors by restricting cell proliferation and survival. We show that Mst1 and Mst2 play redundant roles, and removal of both resulted in early lethality in mouse embryos. Importantly, tumors developed in the liver with a substantial increase of the stem/progenitor cells by 6 months after removing Mst1 and Mst2 postnatally. We show that Mst1 and Mst2 were required in vivo to control Yap phosphorylation and activity. Interestingly, apoptosis induced by TNFα was blocked in the Mst1 and Mst2 double-mutant cells both in vivo and in vitro. As TNFα is a pleiotropic inflammatory cytokine affecting most organs by regulating cell proliferation and cell death, resistance to TNFα-induced cell death may also contribute significantly to tumor formation in the absence of Mst1 and Mst2.  相似文献   
33.
34.
The assessment and stratification of patients with chest pain in the emergency unit may indicate the appropriate therapy for each patient based on the probability of the presence of acute coronary artery disease and on the risk of its major cardiac events. That assessment is based on the triplet: clinical setting, electrocardiographic findings, and markers of myocardial lesion. We report the case of a 58-year-old male chagasic patient admitted to the emergency unit due to chest pain and palpitations, with an electrocardiogram showing sustained ventricular tachycardia and positive troponin measurement (0.99 ng/mL). The patient underwent cine coronary angiography, which evidenced no obstructive coronary artery disease.  相似文献   
35.
The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation. Perfect absorption and anti-reflection of wet hanging PANi-cotton fabrics cause quick transfer of total incident light into water confining nearly 100% of the sunlight. As a result, a hanging membrane is found to have more attractive properties than a floating above water fabric. We find, however, that the photothermal properties of a floating PANi-cotton membrane can greatly be enhanced by dispersing TiN nanoparticles in the water below the fabric. The calculated temperature gradients for TiN nanoparticle solutions show that the absorbed energy grows with increasing the nanoparticle density and that the photothermal process occurs mostly near the surface. The collective heating effects depend on the size and density of nanoparticles, which can further be used to modulate the photothermal process.

The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation.  相似文献   
36.
BACKGROUND: Congenital syphilis (CS) reports in Russia increased 26-fold from 1991 to 1999. Case reports included only infants who were clinical cases, had persistent serologic changes, or confirmed syphilitic stillbirth. Although not reported, policies stipulate that infants of inadequately treated or untreated mothers receive preventive penicillin treatment. GOAL: We examined whether risk factors and consequences for epidemiologic cases of CS (infants of inadequately treated mothers) resembled those of clinical cases and differed from those of noncases (infants of adequately treated mothers). STUDY DESIGN: A retrospective record review from Maternity Houses in 5 sites identified 715 syphilis-infected women who gave birth. RESULTS: Among women with maternal syphilis, 11% (n = 81) of infants were clinical cases, 56% (n = 402) were epidemiologic cases, and 33% (n = 232) were noncases of CS. Compared with noncases, maternal risk factors for epidemiologic cases included nonresidence (P <0.01), late syphilis (P <0.01), unemployment (P <0.01), no prenatal care (P <0.01), and syphilis testing at >/=28 weeks (P <0.01). Each of these was also significant for being a clinical case. Associated consequences of CS for the epidemiologic cases included increases in stillbirth (P <0.01), preterm birth (P <0.01), low birth weight (P <0.01), transfer to a pediatric hospital (P <0.01), and abandonment (P <0.05). Each of these except stillbirth was significantly elevated among clinical cases. Nearly half of the epidemiologic cases had no record of any penicillin treatment for the infant. Epidemiologic cases were significantly more likely than noncases to have no clinical or laboratory follow up. CONCLUSION: In Russia, maternal risk factors and perinatal consequences for epidemiologic cases of CS resembled those of clinical cases. Expanding national reporting to include epidemiologic cases would strengthen CS prevention and monitoring.  相似文献   
37.
In recent years, websites that stress the message of thinness as the ideal and only choice have surfaced on the internet. The possibility that pro-anorexia websites may reinforce restrictive eating and exercise behaviors is an area of concern. In addition, friends may be influencing one another to view these websites, further contributing to drive for thinness in women and drive for muscularity in men. Three hundred male and female undergraduate psychology students responded to questionnaires assessing: internalization of pro-anorexia website content, internalization of general media content, influence of friends to view pro-anorexia websites, peer influence, drive for muscularity, and drive for thinness. Results showed internalization of pro-anorexia website content was positively correlated with drive for thinness in women, and negatively correlated with drive for muscularity in men. Internalization of pro-anorexia website content was found to be related to both drive for thinness in women and drive for muscularity in men.  相似文献   
38.
Myoinhibitory peptides (MIPs) are a family of insect W(X(6))Wamides with inhibitory effects on visceral muscles and juvenile hormone synthesis. Although MIPs are widely distributed within the nervous system, a detailed analysis of their distribution and function in insect brains is still missing. We analyzed the distribution of MIPs in the brain of the cockroach Leucophaea maderae. We focused on the accessory medulla (AMe), a small neuropil near the medulla that acts as the master circadian clock. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) and Nano-LC electrospray ionization (ESI) mass spectrometry revealed five Lem-MIPs in preparations of the AMe and corpora cardiaca. The complete sequences of two of these peptides were identified. Immunocytochemistry revealed wide distribution of MIP-related peptides in the cockroach brain. The superior median protocerebrum, parts of the central complex, and the tritocerebrum showed particularly dense immunostaining. In contrast, only a few local interneurons were stained in the antennal lobe and a few extrinsic neurons in the mushroom body, including a giant neuron innervating the calyces. The noduli of the AMe showed dense immunostaining, and neurons in all AMe cell groups except the anterior neurons were labeled. Pigment-dispersing factor- (PDF) and MIP immunostaining was colocalized in two neurons of the AMe. No colocalization of MIP- and PDF immunostaining was detected in the anterior optic commissure, but two small PDF-immunoreactive commissural fibers near the posterior optic commissure showed colocalized MIP immunostaining. The results suggest that several MIPs participate in different functional circuits of the circadian system and are involved in multiple brain circuits of the Madeira cockroach.  相似文献   
39.
Systemic or intraventricular administration of opiate compounds induces not only analgesia but also the reciprocal responses of increased prolactin and decreased luteinizing hormone (LH) release. Electrical stimulation of the ventral periaqueductal gray (VPAG) or dorsal raphe nucleus (DRN) also inhibits both pain perception and LH release. In the present experiments prolactin release in response to stimulation of the VPAG-DRN was studied in ovariectomized rats. Stimulation was delivered through chronically implanted bipolar electrodes for 2 h. Blood samples collected at 10-min intervals through an indwelling jugular cannula were assayed for prolactin by radioimmunoassay. Increased release of prolactin followed increased intensity of stimulation (0.5, 1.0, 2.0 mA) in animals pretreated (10 min before initial blood sample) with saline. Naltrexone (3.7 mg/kg, i.v.) pretreatment was ineffective in antagonizing the effect of stimulation. Response to stimulation of the posterior VPAG-DRN was significantly greater than that to stimulation of more anterior VPAG-DRN loci at a current of 1.5 mA but not at 2.0 mA. Stimulation with a current of 0.5 mA was ineffective in releasing prolactin when applied to the VPAG-DRN, but when delivered to the periaqueductal gray directly lateral to the cerebral aqueduct, marked aversive and prolactin responses resulted. Taken together these data indicate that the VPAG in the region of the DRN contains a specific system capable of stimulating prolactin release and that opiate receptors are not interposed between the mesencephalic sites of activation of this pathway and the hypothalamic-hypophyseal portal system.  相似文献   
40.
In the present study the olfactory system of hereditary ataxia patients was tested using the smell identification test. Two previous findings suggested a possible olfactory impairment in these patients. First, an olfactory dysfunction has been found in different neurodegenerative diseases, and second, human functional imaging has shown cerebellar activation during olfaction. As an initial approach to determine if cerebellar ataxia impairs the olfactory process, cerebellar ataxia patients, along with basal ganglia patients, were tested. The results show an olfactory deficit in both basal ganglia and hereditary ataxia patients. Further exploration of the olfactory capacities in hereditary ataxia is necessary to elucidate the specific nature of the deficits.  相似文献   
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