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31.
Study of the ultrastructure of the microcirculation tract in patients suffering from chronic pneumonia with bronchiectasis and abscess formation revealed involvement of all parts of the pulmonary and pleural microcirculation system, including intra-and extravascular disorders and changes in the vascular wall. Combination of rheological disorders and dyscoagulation in the microvessels with stable increase in vascular permeability and changes in the components of the aerohematic barrier leads to disturbances of metabolic and hemodynamic homeostasis in the lungs, advancement of the suppurative process, and increase of pulmonary hypertension.  相似文献   
32.
Little is known about the physiological roles of the M5 muscarinic receptor, the last member of the muscarinic receptor family (M1-M5) to be cloned. In the brain, the M5 receptor subtype is preferentially expressed by dopaminergic neurons of the substantia nigra and the ventral tegmental area. Dopaminergic neurons located in the ventral tegmental area are known to play important roles in mediating both the rewarding effects of opiates and other drugs of abuse and the manifestations of opiate/drug withdrawal symptoms. We therefore speculated that acetylcholine-dependent activation of M5 receptors might modulate the manifestations of opiate reward and withdrawal. This hypothesis was tested in a series of behavioral, biochemical, and neurochemical studies using M5 receptor-deficient mice (M5-/- mice) as novel experimental tools. We found that the rewarding effects of morphine, as measured in the conditioned place preference paradigm, were substantially reduced in M5-/- mice. Furthermore, both the somatic and affective components of naloxone-induced morphine withdrawal symptoms were significantly attenuated in M5-/- mice. In contrast, the analgesic efficacy of morphine and the development of tolerance to the analgesic effects of morphine remained unaltered by the lack of M5 receptors. The finding that M5 receptor activity modulates both morphine reward and withdrawal processes suggests that M5 receptors may represent a novel target for the treatment of opiate addiction.  相似文献   
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Pilonidal sinus surgery could, as of now, be considered a surgery tailored more to the surgeon than to the patient. In an attempt to give to surgeons an objective instrument of decision, we have evaluated which variables could be considered predictive of postoperative complications after pilonidal sinus surgery. A prospective electronic database of all patients treated for sacrococcygeal pilonidal disease was analysed. Sex, age, obesity, smoking, recurrent disease, the presence of multiple orifices and the distance between the most lateral orifice and midline were recorded and correlated with the occurrence of postoperative complications (infection and recurrence); 1006 patients were evaluated. Excision with primary mid‐line closure was performed on all the patients. Mean follow‐up was 7·3 ± 3·6 years. A total of 158 patients with postoperative complications (infection and/or recurrence) were recorded during this period. A multivariate analysis showed that, after adjusting for major clinical and demographic characteristics, only a recurrent disease [odds ratio (OR): 3·41, 95% confidence interval (CI): 1·89–6·15, P < 0·001] and the distance of lateral orifice from midline (OR: 26·3, 95% CI: 12·2–56·7, P < 0·001) were independent predictors of overall postoperative complications. Focussing on the distance from midline, the receiver operative characteristic (ROC) analysis showed that the distance of lateral orifice from midline predicted 79·2% of complications and the Youden's test identified the best cut‐off as 2·0 cm for this variable. An evidence‐based tool for deciding on the type of surgical intervention could be developed and validated by further ad hoc prospective studies evaluating our results in comparison to other different types of surgical techniques. Our results support the use of these variables as an effective way to tailor pilonidal sinus surgery to the patient, so as to obtain the best results in patient care.  相似文献   
35.
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain.  相似文献   
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We developed a new experimental model of oxidative stress in rats, which combines the effects of 3-vessel brain ischemia and an increased level of homocysteine in blood circulation. We compared the protective effects of two compounds, the agonist of cannabinoid receptors Win5521-2 and the natural antioxidant carnosine. We found that Win5521-2 has a protective effect only at a normal blood level of homocysteine, whereas carnosine is also effective under conditions of elevated homocysteine level.  相似文献   
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The incidence rate of laryngeal papillomas in a Danish subpopulation (approximately 2.8 million inhabitants) was 3.84 × 10-6 per year in the period 1968–1984. For juvenile papillomas the incidence rate was 3.62 × 10-6, compared with 3.94 × 10-6 for laryngeal papillomas of adult onset. When comparing different time periods a significantly low incidence was found in the time 1965–1968, while the incidence remained constant in 1969–1984. The low incidence rate in the early period may be real, but selectional bias may have played a part. It is in general anticipated that maternal genital HPV-infections may serve as an HPV-reservoir, and that juvenile laryngeal papilloma is a result of HPV transmission from the mother to the child during birth. In the period in question cervical HPV-infections have been recorded with increasing frequency in younger women, indicating that the prevalence is rising. However, this is not reflected in the incidence of laryngeal papillomas.  相似文献   
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