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991.
Vanadium compounds have become important in industrial processes, resulting in workplace exposure potential and are present in ambient air as a result of fossil fuel combustion. A series of acute nose-only inhalation toxicity studies was conducted in both rats and mice in order to obtain comparative data on the acute toxicity potential of compounds used commercially. V2O3, V2O4, and V2O5, which have different oxidation states (+3,?+4,?+5, respectively), were delivered as micronized powders; the highly water-soluble and hygroscopic VOSO4 (+4) could not be micronized and was instead delivered as a liquid aerosol from an aqueous solution. V2O5 was the most acutely toxic micronized powder in both species. Despite its lower overall percentage vanadium content, a liquid aerosol of VOSO4 was more toxic than the V2O5 particles in mice, but not in rats. These data suggest that an interaction of characteristics, i.e., bioavailability, solubility and oxidation state, as well as species sensitivity, likely affect the toxicity potential of vanadium compounds. Based on clinical observations and gross necropsy findings, the lung appeared to be the target organ for all compounds. The level of hazard posed will depend on the specific chemical form of the vanadium. Future work to define the inhalation toxicity potential of vanadium compounds of various oxidation states after repeated exposures will be important in understanding how the physico-chemical and biological characteristics of specific vanadium compounds interact to affect toxicity potential and the potential risks posed to human health.  相似文献   
992.
993.
Aim: Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic kyphosis and flexed posture is affected. Furthermore, instruments measuring postural control were evaluated and examined for sensitivity and easy clinical use. Methods: Until February 2011, electronic databases were systematically searched for cross‐sectional studies. Methodological quality was assessed with a modified Downs & Black scale. Results: Of the 518 found studies, 18 studies were included. Postural control was generally affected for patients with vertebral fractures, thoracic kyphosis and flexed posture. Patients with osteoporosis had impaired postural control when assessed with computerized instruments. Easy performance‐based tests did not show any impairments. Conclusions: There is evidence for an impaired postural control in all patient groups included. Impaired postural control is an important risk factor for falls. Functional performance tests are not sensitive and specific enough to detect affected postural control in patients with osteoporosis. To detect impaired postural control among osteoporotic patients and to obtain more insight into the underlying mechanisms of postural control, computerized instruments are recommended, such as easy‐to‐use ambulant motion‐sensing (accelerometry) technology. Geriatr Gerontol Int 2012; ??: ??–??.  相似文献   
994.
995.
YF Liu  Y Kim  T Yoo  P Han  JC Inman 《Oral diseases》2018,24(3):325-334
Burning mouth syndrome (BMS) is a chronic oral pain syndrome that primarily affects peri‐ and postmenopausal women. It is characterized by oral mucosal burning and may be associated with dysgeusia, paresthesia, dysesthesia, and xerostomia. The etiology of the disease process is unknown, but is thought to be neuropathic in origin. The goal of this systematic review was to assess the efficacy of the various treatments for BMS. Literature searches were conducted through PubMed, Web of Science, and Cochrane Library databases, which identified 22 randomized controlled trials. Eight studies examined alpha‐lipoic acid (ALA), three clonazepam, three psychotherapy, and two capsaicin, which all showed modest evidence of potentially decreasing pain/burning. Gabapentin was seen in one study to work alone and synergistically with ALA. Other treatments included vitamins, benzydamine hydrochloride, bupivacaine, Catuama, olive oil, trazodone, urea, and Hypericum perforatum. Of these other treatments, Catuama and bupivacaine were the only ones with significant positive results in symptom improvement. ALA, topical clonazepam, gabapentin, and psychotherapy may provide modest relief of pain in BMS. Gabapentin may also boost the effect of ALA. Capsaicin is limited by its side effects. Catuama showed potential for benefit. Future studies with standardized methodology and outcomes containing more patients are needed.  相似文献   
996.
997.
Chikungunya virus (CHIKV) was first isolated in humans in 1952, following an epidemic in Tanzania. The origin of the name means “to bend forward or become contorted,” in reference to the posture adopted by patients due to the joint pain that occurs during the infection. Epidemiology data suggest that by the end of 2015, about 1.6 million people had been infected with CHIKV. The acute period of the disease is characterized by high fever, myalgia, joint pain, and severe and disabling polyarthritis, sometimes accompanied by headache, backache, and maculopapular rash, predominantly on the thorax. Around half of the patients will progress to the subacute and chronic phases, that is manifested by persistent polyarthritis/polyarthralgia, accompanied by morning stiffness and fatigue, which could remain for years. Oral features may include gingivitis possibly as a consequence of arthralgia of the hands leading to limited oral health measures as well as burning sensation and oral mucosal ulceration. Treatment in the acute phase includes acetaminophen, and weak opioids (tramadol or codeine) should be used in cases of severe or refractory pain. For patients who have progressed to the subacute stage and who have not had notable benefit from common analgesics or opioids, NSAIDs, or adjunctive pain medications (anticonvulsants or antidepressants) may be of benefit. In patients with moderate‐to‐severe musculoskeletal pain or in those who cannot be given or tolerate NSIADs or opiates, prednisolone should be prescribed.  相似文献   
998.
Zika virus (ZIKV) infection has been recognised since 1947, but just recently it became a worldwide major public health problem. The most common features of ZIKV infection are fever, cutaneous rash, arthralgia and conjunctivitis but most affected patients with the clinical disease present with only mild symptoms. However, severe neurological complications have been described: there is an occasional association with Guillain–Barre syndrome, and emerging data indicate an association between vertical transmission of ZIKV infection and microcephaly, but no specific orofacial manifestations have yet been reported. ZIKV is present in body fluids and has also been demonstrated in the saliva, but there is as yet no reliable evidence to support ZIKV transmission via this pathway. Transmission in oral health care should be effectively prevented using standard infection control measures. There are currently no specific treatments for Zika virus disease and no vaccines available, so prevention of ZIKV is based on vector control.  相似文献   
999.

Introduction

Necrotising fasciitis is a life-threatening illness that is often difficult to diagnose. Immediate debridement and intravenous antibiotic therapy are required to limit the spread of infection. This five-year audit aimed to review the number and outcomes of all cases of necrotising fasciitis admitted to a tertiary referral unit and to assess the validity of the Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) scoring system.

Methods

A retrospective analysis of patient notes over the five-year period from October 2006 to October 2011 was undertaken. The LRINEC score was calculated for each patient to evaluate its usefulness.

Results

Overall, 15 patients were diagnosed with necrotising fasciitis. Three patients died. The median age of patients was 51.0 years (range: 34–76 years). There were no obvious predisposing factors in 8 cases but patients had a median of 2.0 co-morbidities. The most common infective agent, present in five patients, was Group A Streptococcus. Other monomicrobial agents included Group G Streptococcus and Klebsiella pneumoniae. Polymicrobial infections were less common than monomicrobial infections and two patients had a polymicrobial infection including methicillin-resistant Staphylococcus aureus. Although the LRINEC scoring system identified 12 of the 15 patients as having a high or intermediate likelihood of necrotising fasciitis, 3 were classified as low likelihood.

Conclusions

This limited case series strongly suggests that the LRINEC system is too insensitive for diagnosis.  相似文献   
1000.

Background

Disseminated histoplasmosis is a rare fungal infection and most documented cases are in immune-compromised individuals such as those with acquired immuno-deficiency syndrome.

Objective

To describe a case of disseminated histoplasmosis in an adolescent girl.

Method

We report a case of disseminated histoplasmosis in a 13-year-old adolescent girl. She was admitted for 16 days because of neck masses of 3 years duration, generalized body swelling of 3 months and reduction in urinary output of 2 months. She tested negative for human immunodeficiency virus antibodies.

Result

An autopsy was performed because a definitive diagnosis could not be made while the patient was still alive. The autopsy revealed central caseating areas in the lymph nodes and membranoproliferative glomerulonephritis. The periodic acid-Schiff staining technique for tissues showed viable yeast cells suggestive of histoplasmosis. Zeihl-Neelsen''s staining for mycobacteria tuberculosis was negative.

Conclusion

Undiagnosed case of disseminated histoplasmosis while the patient was alive is being reported in a 13-year-old girl. Disseminated histoplasmosis should be considered as a differential diagnosis of childhood chronic infections and malignancies as in Nigeria.  相似文献   
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