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81.
Cerebrospinal fluid dynamics were studied in 14 dogs with spontaneous hydrocephalus. In nine of the dogs aqueductal obstruction was observed and the remainder had a `communicating type' hydrocephalus. The major histological findings consisted of severe ependymal destruction, spongy changes in the periventricular white matter, increased density of capillaries in this area, and varying degrees of thickening, fibrosis, and fusion of the choroid villi. The formation and absorption of CSF were studied by perfusion of the cerebral ventricles. The rate of formation of CSF was found to decrease with perfusion pressure by Vf = 0·02595−0·00022 P ml./min (P = pressure in cm H2O). The absorption of spinal fluid was found to increase linearly with pressure by Va = 0·0165 + 0·00050 P. The various factors influencing the formation and absorption of the spinal fluid are discussed. The meaning and attainment of `arrest' of the hydrocephalic process in terms of the measured rates of CSF formation and absorption in these animals are considered.  相似文献   
82.
Fipronil is a phenylpyrazole insecticide introduced for pest control, but it can also affect non-target insects such as honeybees. In insects, fipronil is known to block GABA receptors and to inhibit ionotropic glutamate-gated chloride channels, but the behavioral effects of low doses are not yet fully understood. We have studied the effect of sublethal doses of fipronil on the behavior of the honeybee (Apis mellifera) under controlled laboratory conditions. The drug was either administered orally or applied topically on the thorax. A significant reduction of sucrose sensitivity was observed for the dose of 1 ng/bee 1 h after a thoracic application. No significant effect on sucrose sensitivity was obtained with acute oral treatment. A lower dose of fipronil (0.5 ng/bee applied topically) impaired the olfactory learning of the honeybees. By contrast, locomotor activity was not affected. Our results suggest a particular vulnerability of the olfactory memory processes and sucrose perception to sublethal doses of fipronil in the honeybee.  相似文献   
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Noscapine suppresses angiotensin converting enzyme inhibitors-induced cough   总被引:1,自引:0,他引:1  
BACKGROUND: Dry cough is a common side-effect of the angiotensin converting enzyme inhibitors (ACEI) and is a major limiting factor of their use. It has been suggested that ACEI cause this side-effect by potentiation of the bradykinin effect. Previous work in our laboratory has shown that noscapine, an antitussive drug, inhibits the effect of bradykinin. METHODS: To investigate the effect of noscapine on ACEI-induced cough, 611 hypertensive patients who were being treated with ACEI were evaluated for the incidence of persistent dry cough. RESULTS: A cough had developed in 65 (10.6%) patients, two (3.1%) of whom also had severe respiratory distress that required hospitalisation and immediate discontinuation of the ACEI. Forty-two (64.6%) patients had developed a mild cough and 21 (32.3%) patients had developed a moderate to severe cough. The patients with moderate to severe cough received 15 mg of noscapine, orally three times daily, while they continued ACEI. Noscapine effectively resolved the cough in 19 (90%) patients within 4-9 days of starting treatment. CONCLUSION: Noscapine, possibly by inhibition of bradykinin synthesis, eliminates ACEI-induced cough in the majority of patients and allows them to continue with ACEI therapy.  相似文献   
86.
BACKGROUND AND AIM OF THE STUDY: Papillary fibroelastoma (PFE) is a rare and histologically benign tumor, but it may have malignant propensity for life-threatening complications. Herein are described four cases of PFE which reflect the clinical diversity of this lesion. The diagnostic and surgical approach utilized is also briefly reviewed. METHODS: The files of four patients with cardiac valvular PFE treated at the authors' center between January 2002 and November 2003 were reviewed. The diagnosis was strongly suggested by echocardiography. Tumors were noted in aortic (n = 2), mitral (n = 1) and tricuspid (n = 1) sites. Indications for surgery were myocardial infarction (both aortic tumors), previous stroke (mitral tumor), and preventive (tricuspid tumor). RESULTS: Surgical excision with a conservative, valve-sparing approach was performed in all cases. For the first aortic tumor, the aortic valve was reconstructed with a patch of autologous pericardium. None of the patients had evidence of valvular regurgitation after excision on intraoperative transesophageal echocardiography, and all had an uneventful recovery. There were no cases of recurrence or regurgitation on follow up echocardiography. CONCLUSION: PFE is an uncommon but increasingly recognized cause of embolic phenomena. Prompt identification allows for surgical excision, which seems to be curative, safe and well-tolerated. A conservative valve-sparing approach is recommended because of the absence of recurrence after total excision.  相似文献   
87.
Cerebrospinal fluid turnover in experimental hydrocephalic dogs   总被引:1,自引:0,他引:1  
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88.
Elderly suicide is an index of more widespread disorder and discontent among the elderly, and furthermore is a potentially preventable cause of death. This study used coroner's inquest records of 200 elderly in Cheshire who killed themselves, and in which their unexpected deaths attracted a verdict of suicide. Sociodemographic characteristics, clinical aspects of the suicidal process and health care contact before death are reviewed. Unlike most available studies, cases of unexpected death in which an open verdict was given were not included in this study, which covered a 13 year period. The findings are interpreted and compared to the currently available literature on suicide in the elderly. Late life suicide is characterised by less warning, higher lethality and greater prevalence of depression and physical illness. However, suicide risk often remains undetected. All suicidal behaviour in the elderly should be taken seriously by psychiatric and primary care services, in order to reduce suicide rates in the elderly.  相似文献   
89.
Acquired resistance towards apoptosis is the hallmark of most if not all types of cancer. We have previously identified and characterized ARTS, a broadly expressed protein localized to mitochondria. ARTS was initially shown to mediate TGF-beta induced apoptosis. Recently, we have found that high levels of ARTS induce apoptosis without additional pro-apoptotic stimuli. Further, ARTS promotes apoptosis in response to a wide variety of pro-apoptotic stimuli. Here, we report that the expression of ARTS is lost in all lymphoblasts of more than 70% of childhood acute lymphoblastic leukemia (ALL) patients. The loss of ARTS is specific, as the related non-apoptotic protein H5, bearing 83% identity to ARTS, is unaffected. During remission, ARTS expression is detected again in almost all patients. Two leukemic cell lines, ALL-1 and HL-60 lacking ARTS, were resistant to apoptotic induction by ara-C. Transfection of ARTS into these cells restored their ability to undergo apoptosis in response to this chemotherapeutic agent. We found that methylation process contributes to the loss of ARTS expression. We conclude that the loss of ARTS may provide a selective advantage for cells to escape apoptosis thereby contributing to their transformation to malignant lymphoblasts. We therefore propose that ARTS can function as a tumor suppressor protein in childhood ALL.  相似文献   
90.
The authors report three cases of non-tuberculous epidural abscess. Presenting symptoms included lumbar back pain, muscle spasms, soft tIssue swelling, and neurological deficits in all three cases. MR imaging was helpful for diagnosis and showed involvement of perivertebral soft tissues and an epidural abscess of variable size. There was no significant involvement of intervertebral disks or vertebrae. Diagnosis was confirmed by bacteriologic exam. Clinical outcome was favourable with antibiotic treatment.  相似文献   
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