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排序方式: 共有1006条查询结果,搜索用时 703 毫秒
61.
The new 64-slice multi-detector computed tomographic scanners with improved temporal and special resolution are well suited to cardiac scanning allowing large area coverage and very short scan time. Current applications include plaque and stenosis assessment, evaluation of bypass graft patency and stenosis, coronary artery anomalies and recently, assessment of implanted coronary stents. Possible fields of utilization include emergency room triage of chest pain, and screening prior to invasive angiography in order to reduce the load of invasive studies. The future holds the prospect of automatic analysis of coronary plaque and luminal stenosis possibly opening up a new vista for non-invasive risk assessment. 相似文献
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Protection of cultured Cyprinus carpio against a lethal viral disease by an attenuated virus vaccine 总被引:1,自引:0,他引:1
Massive mortality of koi and common carp--Cyprinus carpio species--has been observed since 1998 in many countries worldwide, resulting in severe economic losses. The cause of the disease is an as yet unclassified large DNA virus, designated carp nephritis gill necrosis virus (CNGV) or koi herpes virus (KHV). Previously, we demonstrated that the wild type CNGV lost its pathogenecity following serial transfer in cell culture, and that clones isolated from the attenuated population can be used as a prophylactic vaccine. Here, we describe the basic conditions required for proper fish immunization so that a protection protocol may be devised. We demonstrated that carps are very sensitive to the pathogenic and the attenuated viruses, and short immersion of fish in water containing the viruses is sufficient for infection. The infection of fish with the pathogenic and the attenuated viruses is temperature-restricted; fish held at the non-permissive temperature, immediately following infection, were not affected by the pathogenic virus, and were not rendered resistant to the disease. Thus, propagation of the virus in the fingerlings is a pre-requisite for immunization. In order to increase the number of random mutations in the genome of the attenuated virus, and thus, reduce the possibility of the attenuated virus reverting to pathogenic, we irradiated it and selected additional clones appropriate for vaccination. The results of our study suggest that a safe and efficient prophylactic vaccine can be developed by selecting an appropriate attenuated virus. 相似文献
64.
Groutz A Rimon E Peled S Gold R Pauzner D Lessing JB Gordon D 《Neurourology and urodynamics》2004,23(1):2-6
AIMS: Stress urinary incontinence (SUI) in young women is usually the result of pelvic floor injury during vaginal delivery. Whether cesarean section delivery may prevent such injury is questionable. We undertook a prospective study to compare the prevalence of SUI among primiparae 1 year after spontaneous vaginal delivery versus elective cesarean section, or cesarean section performed for obstructed labor. METHODS: Three hundred and sixty-three consecutive primiparae were recruited immediately after delivery and were followed for 1 year. Women were asked upon recruitment whether they had ever experienced SUI before pregnancy. Those who had SUI before pregnancy were excluded. Thus, only cases of de novo childbirth-associated SUI were analyzed. Patients were divided into three subgroups according to the mode of delivery: spontaneous vaginal delivery (n = 145), elective cesarean section (n = 118), and cesarean section performed for obstructed labor (n = 100). Patients who underwent elective cesarean section were not given a trial of labor. Cesarean sections for obstructed labor were performed at a mean cervical dilatation of 8.7 +/- 1.6 cm and arrest of 184 +/- 24 min. Prevalence, frequency, and severity of postpartum SUI, as well as demographic and obstetric parameters, were analyzed in each subgroup. RESULTS: The three subgroups were comparable with respect to maternal age, weight, and height. Prevalence of postpartum SUI was similar after spontaneous vaginal delivery (10.3%) and cesarean section performed for obstructed labor (12%). However, SUI was significantly less common following elective cesarean section with no trial of labor (3.4%, P < 0.05). Approximately half of the symptomatic patients in each subgroup reported either moderate or severe symptoms, however, only 15-18% expressed their desire for further evaluation. CONCLUSIONS: Prevalence of postpartum SUI is similar following spontaneous vaginal delivery and cesarean section performed for obstructed labor. It is quite possible that pelvic floor injury in such cases is already too extensive to be prevented by surgical intervention. Conversely, elective cesarean section, with no trial of labor, was found to be associated with a significantly lower prevalence of postpartum SUI. Whether the prevention of pelvic floor injury should be an indication for elective cesarean section is yet to be established. 相似文献
65.
BACKGROUND: Some patients are referred for Mohs surgery with no or minimal clinical evidence of skin cancer at the biopsy site. OBJECTIVE: To determine the incidence of residual skin cancer at biopsy sites during Mohs micrographic surgery. METHODS: We evaluated all patients that underwent Mohs surgery for basal cell and squamous cell carcinomata in one year. The study was carried out prospectively. Debulking was done using a no. 15 blade at the clinical borders of the tumor or biopsy site. All specimens were sectioned at the middle and cut to the periphery at 20- microm intervals. RESULTS: Seven hundred and forty-one patients underwent operations. In 390 patients, a biopsy was performed prior to surgery. A total of 351 patients were biopsied as prestaged (chemocheck) during surgery. Ninety-nine (25%) of the preoperatively biopsied patients showed no residual tumor in the debulking specimen or the first layer. Of these 99 patients, 84 had basal cell carcinoma and 15 had superficial or in situ squamous carcinoma. CONCLUSIONS: In this study, preoperative biopsy for diagnosis of skin cancer of the face was curative in 25% of patients, despite pathologic diagnosis of incompletely excised tumor. However, as the majority of preoperatively biopsied patients showed residual tumor, Mohs micrographic surgery is indicated in all patients with incomplete removal of skin cancer of the head and neck. 相似文献
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68.
Spiegel R Zalman L Gavriel H Horovitz Y 《Journal of pediatric hematology/oncology》2003,25(9):747-749
A 3-year-old child with idiopathic hypereosinophilic syndrome (IHES) presented with sore throat and pharyngeal exudate. Recurrent throat cultures were negative and microscopic section of the exudate revealed an extensive eosinophilic infiltration. Fourteen months later, the child still has marked hypereosinophilia and pharyngeal involvement without other organ involvement. Eosinophilic pharyngitis may be a target organ in IHES. The benign clinical course and the laboratory characteristics are described. 相似文献
69.
Functional impairment of the vestibular end organ resulting from impulse noise exposure 总被引:2,自引:0,他引:2
OBJECTIVES/HYPOTHESIS: To assess the effect of exposure t o impulse noise, known to cause damage tothe cochlea, on the vestibular part of the inner ear using short latency vestibular evoked potentials (VsEPs), which is a direct and objective test for evaluating the function of the vestibular end organs. STUDY DESIGN: Prospective animal study. METHODS: Sand rats (Psammomys obesus) underwent baseline measurements of VsEPs in response to linear and angular acceleration stimuli and measurement of the auditory nerve and brainstem evoked response (ABR). The animals were then exposed to 10 gunshots generating impulse noise at an intensity of approximately 160 dB sound pressure level (SPL). Repeat measurements of the evoked potentials were conducted 2 to 4 hours, 1 week, and 6 weeks after the exposure. The amplitude and latency of the first wave of VsEPs in response to linear and angular acceleration stimuli, reflecting the function of the otolith organs and semicircular canals respectively, were compared between baseline and post-exposure measurements, as were ABR thresholds. RESULTS: The amplitude of the first wave of the VsEPs in response to linear acceleration was significantly (P <.001) reduced and the latency significantly (P <.005) prolonged 2 to 4 hours after the exposure in comparison to baselinemeasurements. The latency prolongation persisted in follow-up measurements, whereas the amplitude showed partial recovery. The first wave of VsEPs in response to angular acceleration was unchanged long-term. ABR thresholds were elevated in the long-term by 60 dB. CONCLUSION: It seems that impulse noise not only damages the cochlea, but also causes clear functional impairment to the vestibular end organs, mainly the otolith organs. 相似文献
70.
The opposing effects of endothelin-1 and C-type natriuretic peptide on apoptosis of neonatal rat cardiac myocytes 总被引:3,自引:0,他引:3
Han B Fixler R Beeri R Wang Y Bachrach U Hasin Y 《European journal of pharmacology》2003,474(1):15-20
C-type natriuretic peptide (CNP) and endothelin-1 are paracrine peptides with opposing effects on cardiac myocyte contraction and intracellular cGMP production. Elevated levels of both endothelin-1 and CNP are found in patients with congestive heart failure. These factors may be related to positive and negative regulation of cell apoptosis in the failing heart. To evaluate the effect of CNP and endothelin-1 on apoptosis of cardiac myocytes and the possible mechanisms involved, primary cardiac myocytes were prepared from neonatal Sabra rats. Cardiomyocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and Annexin V in situ staining. The TUNEL method was used to measure the apoptotic index. CNP and the cGMP derivative, 8-br-cGMP, induced apoptosis of cardiac myocytes. CNP-induced apoptosis could be blocked by HS 142-1 (a mixture of 20-30 kinds of linear beta-1, 6-glucan esterified by capronic acid, an antagonist of type A and B natriuretic peptide receptors), and KT 5823 (C29H25N3O5), the inhibitor of cGMP-dependent protein kinase). Alpha-difluoromethylornithine (DFMO), the irreversible inhibitor of ornithine decarboxylase, also induced apoptosis to a similar extent. CNP and 8-br-cGMP caused a marked reduction of intracellular ornithine decarboxylase expression, as determined by Western blot analysis and immunohistochemical assay. Preincubation with endothelin-1 attenuated CNP- and 8-br-cGMP-induced cardiomyocyte apoptosis. Endothelin-1 also antagonized the CNP- and 8-br-cGMP-induced reduction of intracellular ornithine decarboxylase expression. These results suggest that CNP has a proapoptotic effect on neonatal rat cardiac myocytes. The effect is mediated via natriuretic peptide receptors and is due to an elevation of intracellular cGMP, which reduces the expression of intracellular ornithine decarboxylase and probably the production of polyamines. Endothelin-1 protects cardiac myocytes against CNP-induced apoptosis by influencing the cGMP-dependent pathway, and this effect is probably mediated through both a reduction of cGMP and antagonism of the CNP-induced reduction of intracellular ornithine decarboxylase expression. 相似文献