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排序方式: 共有4392条查询结果,搜索用时 15 毫秒
41.
42.
Jo-Lynn S. Tan Niranjan Sathianathen Marcus Cumberbatch Prokar Dasgupta Alexandre Mottrie Ronney Abaza Koon Ho Rha Thyavihally B. Yuvaraja Dipen J. Parekh Umberto Capitanio Rajesh Ahlawat Sudhir Rawal Nicolò M. Buffi Ananthakrishnan Sivaraman Kris K. Maes Gagan Gautam Francesco Porpiglia Levent Turkeri Mahendra Bhandari Benjamin Challacombe James Roscoe Porter Craig R. Rogers Daniel A. Moon 《BJU international》2021,128(Z3):30-35
43.
Marco Lembo Carmela Vedetta Umberto Moscato Michele del Gaudio 《La Medicina del lavoro》2021,112(2):123
Introduction:Due to the COVID-19 pandemic, healthcare workers are now required to use additional personal protective equipment (PPEs) to protect themselves against the virus. That led to an increased clothing insulation which is negatively affecting the perceived healthcare workers’ thermal sensation.Objectives:While demonstrating through software simulations the potential level of thermal discomfort healthcare workers involved in the COVID-19 emergency can be subjected to, this work aims at identifying measures to improve thermal sensation perception and acceptable thermal conditions for medical personnel.Methods:After having obtained the insulation values of individual clothing used by staff during COVID-19 emergency through the use of a thermal well-being evaluation software, the Fanger indexes (PMV - Predicted Mean Vote and PPD - Predicted Percentage of Dissatisfied) were calculated in order to estimate staff satisfaction to microclimatic conditions.Results:The use of COVID-19 additional PPEs with an air temperature equal to 22 °C (normally considered optimal) brings the PMV index equal to 0.6, which corresponds to 11.8 % being unsatisfied (PPD) due to perceived heat.Discussion:The use of additional protective devices significantly increases the clothing insulation level, facilitating the onset of conditions of thermal discomfort in the health workers. Workers engaged in the execution of nasopharyngeal swabs were most affected by the summer weather conditions and certainly represent the most critical category, for which it would be recommended to implement a higher turnover of service to reduce individual exposure time and consequent discomfort. 相似文献
44.
Luisa Zanette Massimo Zucchetti Andrea Freshi Domenico Erranti Umberto Tirelli Maurizio D'Incalci 《Cancer chemotherapy and pharmacology》1990,25(6):445-448
Summary The clinical pharmacokinetics of 4-demethoxydaunorubicin was investigated in 28 cancer patients who received the drug orally. The majority of the patients were elderly (median age, 72 years). Nine of them also received an i. v. dose, and the bioavailability of the oral dose ranged between 9% and 39%. 4-Demethoxydaunorubicin peak levels were achieved 2–4 h after the oral dose in most patients. The drug was rapidly and extensively metabolized to 4-demethoxy-13-hydroxydaunorubicin, which is probably as active as the parent drug. The metabolite levels were much higher and longer lasting than the parent drug, suggesting that it may play an important role in the drug's pharmacological effects. 相似文献
45.
L. Cassano P. Lombardo R. M. Ragona A. Pastore 《European archives of oto-rhino-laryngology》2000,257(9):507-511
Laryngopyocele is a fairly rare disease. It is a complication of laryngocele. Its clinical picture is often alarming; thus
it needs fast differential diagnosis. Computed tomography allows early diagnosis. Surgical treatment permits a complete recovery.
An association between laryngocele and carcinoma of the larynx has been reported by some authors. Three new cases of laryngopyocele
are presented and discussed.
Received: 23 November 1999 / Accepted: 29 May 2000 相似文献
46.
Maria Rosaria Melis Salvatora Succu Umberto Iannucci A. Argiolas 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(5):595-600
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection
and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus
of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented
dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine
of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented
apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In
contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results
confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine
and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity
of nitric oxide in the paraventricular nucleus of the hypothalamus.
Received: 30 September 1996 / Accepted: 24 January 1997 相似文献
47.
Cardillo C Mores N Campia U Musumeci V Motolese M Folli G 《American journal of therapeutics》1994,1(3):198-205
The current study analyzed the effects of different doses of the calcium channel blocker felodipine on cardiovascular response to a set of standardized laboratory tasks. We randomly allocated 21 essential hypertensive patients to receive extended release felodipine 5 mg, felodipine 10 mg and placebo, each given once daily for 2 weeks, according to a double-blind 3-period design. At the end of each treatment period, patients were examined at resting baseline and while performing a mental arithmetic test, a handgrip test and a cycle ergometry test. Compared to placebo, the average fall in resting blood pressure (BP) was of 7.9 ± 5.6/6.1 ± 4.5 mm Hg with felodipine 5 mg (p < 0.01) and of 15.1 ± 5.8/13.9 ± 4.5 mm Hg with felodipine 10 mg (p < 0.001). During mental arithmetic, BP decrease was 11.6 ± 8.1/9 ± 5 mm Hg with felodipine 5 mg (p < 0.01) and 20.4 ± 8.1/15.3 ± 5 mm Hg with felodipine 10 mg (p < 0.001). During handgrip test, BP was significantly reduced after both felodipine doses by 11.7 ± 9.3/9.5 ± 6.5 mm Hg (p < 0.05) and 22.1 ± 9.3/22.4 ± 6.5 mm Hg (p < 0.001), respectively. During cycle ergometry, systolic BP was significantly reduced after felodipine 10 mg by 20.1 ± 9.4 mm Hg (p < 0.001), whereas the fall induced by felodipine 5 mg (7.7 ± 9.4 mm Hg) was not statistically significant (p > 0.05); diastolic BP was significantly reduced by both felodipine doses [average fall of 6.6 ± 5.8 mm Hg (p < 0.05) after felodipine 5 mg and of 12.7 ± 5.8 mm Hg (p < 0.001) after felodipine 10 mg]. There was no treatment effect on the magnitude of systolic BP reactivity from baseline during either mental arithmetic, handgrip test or cycle ergometry (all, p > 0.05). Heart rate values were significantly higher after both felodipine doses than after placebo, either at rest or during stress testing (all, p < 0.05). These data suggest that felodipine, especially at higher doses, may be effective in lowering BP not only at rest but also during exposure to commonly recurring stressful situations. 相似文献
48.
Leiomyomas are smooth-muscle tumors that may be encountered in the practice of podiatric medicine when they affect the arrector pili muscles or the smooth muscle of a vessel wall. In the present case, the lesion was located on the heel, an area with no hair growth; this further supports the diagnosis, as the most likely origin of the lesion was the smooth muscle of a blood vessel. Vascular leiomyomas show a greater predilection for the lower extremities than their superficial counterparts. Surgical excision is the treatment of choice for these benign lesions, whose prognosis is excellent. When a patient presents with a painful mass in the lower extremity, the diagnosis of leiomyoma should be considered. 相似文献
49.
PURPOSE: The natural history of human breast cancer shows that lesion size correlates directly with nodal metastases and distant spread. Nodal metastases are found in only 6% of cases in the preclinical stage of the tumor and therefore imaging must detect a breast cancer before it becomes palpable. We reviewed 215 nonpalpable breast lesions studied in the last 10 years to assess observers performance and ultimately improve the interpretation of suspicious mammograms, evaluating "cost" in terms of the ratio between benign and malignant lesions (B/M). MATERIAL AND METHODS: From 1988 to October 1998, two hundred and fifteen women with nonpalpable breast lesions suspected at mammography were examined. The lesions were removed after stereotaxic or US location and a radiograph of the surgical specimen was always performed. Mammographic patterns were interpreted retrospectively by two blinded radiologist experienced in breast imaging and specialized in locating nonpalpable breast lesions. Mammographic patterns were classified as poorly/highly suspicious calcifications, regular/irregular masses, spiculated masses, masses with calcifications and parenchymal distortions. Radiographic findings were compared with surgical results and the data used to calculate the B/M, positive predictive value (PPV) for malignancy and the trend of operator's performance. RESULTS: Modern techniques permit to detect a very high number of in situ breast carcinomas. Nineteen of 22 lesions (86%) were detected by mammography as highly suspicious calcifications, 2/22 as spiculated masses and 1/22 as a mass with calcifications. No in situ carcinoma was detected as an irregular mass. All regular masses were proven to be benign at histology. B/M analysis showed a decreasing trend (from 1.94 in the first 3 years to .57 in 1994-96, to .83 in 1997-98) and an overall value of .90. The PPV for malignancy was 83.33% for spiculated masses, 65.5% for highly suspicious calcifications, 63.63% for irregular masses, 47.05% for masses with more or less dysmorphic calcifications, 32.65% for poorly suspicious calcifications, 8.33% for parenchymal distortions and 0% for regular masses. DISCUSSION AND CONCLUSIONS: All spiculated masses and highly suspicious calcifications and microcalcifications should be removed. Biopsy is recommended in parenchymal distortions, despite its low predictive value for malignancy, because these lesions are uncommon and the cost of biopsy is therefore acceptable. Needle aspiration or long-term monitoring can be reconsidered for irregular masses and poorly suspicious microcalcifications. Finally, relative to possible different interpretations of mammographic patterns by center and operator's experience, we suggest that the PPV for every single pattern be continually reassessed based on personal case records rather than on literature data. This holds true especially for microcalcifications. 相似文献
50.
A comparison of electrophysiological tests for the early diagnosis of diabetic neuropathy 总被引:4,自引:0,他引:4
Clinical criteria and several electrophysiological parameters for detecting nerve damage were compared in 99 patients with diabetes mellitus type 1 and type 2. Abnormal results were found in sural/radial amplitude ratio (51%), minimal F-wave latency of the tibial nerve (36.4%), sensory conduction velocity of the sural nerve (29.8%), and sural sensory nerve action potential amplitude (29.3%) when pooling data from all patients and comparing them to age- and height-matched normal control subjects. Analysis of all the parameters revealed large differences between the diabetes mellitus type 1 and type 2 groups, suggesting that the type of diabetes must be taken into account when comparing the sensitivity of nerve conduction tests. In diabetes mellitus type 1, the sural/radial ratio had the clearest correlation with course of illness and was the first parameter to show a significant reduction. We conclude that the simple ratio between sural and radial amplitudes is a very sensitive parameter and abnormalities in this ratio provide the means for earliest detection of neuropathy in diabetes mellitus type 1. 相似文献