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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Delineating the sites and progression of in vivo atrophy in multiple system atrophy using fluid-registered MRI. 总被引:1,自引:0,他引:1
Jonathan M Schott Jessica E Simon Nick C Fox Andrew P King M Nadeem Khan Lisa Cipolotti Dominic C Paviour John M Stevens Martin N Rossor 《Movement disorders》2003,18(8):955-958
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA. 相似文献
93.
Dennis M Mello MD Doff B McElhinney MS Andrew J Parry MD Norman H Silverman MD Frank L Hanley MD 《The Annals of thoracic surgery》1997,64(6):1808-1810
In hearts with a common arterial trunk (truncus arteriosus), there is almost always an inverse development of the aortic arch and the ductus arteriosus. Truncus with a normal aortic arch and a patent ductus is a rare echocardiographic and surgical finding. In this report, we describe 2 neonates in whom truncus arteriosus with a normal aortic arch and a medium or large patent ductus was diagnosed by preoperative echocardiography (without catheterization) and confirmed intraoperatively. 相似文献
94.
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96.
Seventy-three patients with lip carcinoma were treated from 1970 to 1988 in the Otolaryngology Department of the Beilinson Medical Center. The most common histological type was squamous cell carcinoma which occurred in 68 patients; four tumours were basal cell carcinoma and one acinic cell carcinoma. Carcinoma of the lip is more frequent in males. Nevertheless, the frequency of carcinoma in females in our series was substantially higher than the average reported in the literature. Forty-nine patients were treated surgically and 24 patients were treated by irradiation. Analysis of the results among those treated by surgery and those treated by irradiation shows a difference in tumour local control which was statistically significant (p = 0.025). Surgical treatment is recommended because of the advantage of tumour margin assessment, avoidance of radiotherapy complications and rapid rehabilitation. Two rare cases of carcinoma of the lip in young patients (age under 20 years) are presented. 相似文献
97.
The purpose of this investigation was to determine the effect of nephrotic syndrome (NS) on the pharmacodynamics of a barbiturate. NS was induced in male rats by puromycin aminonucleoside; it caused hypoproteinemia, increased liver and kidney weight and elevated serum creatinine and urea nitrogen concentrations. Serum albumin concentration decreased from 3.5% in controls to 0.90% in NS animals. The rats were infused i.v. with heptabarbital, 1 mg/min, until they lost their righting reflex. The total dose (mean +/- S.D.) required by rats with NS, 40.2 +/- 4.2 mg/kg, was substantially lower than that required by normal animals (68.6 +/- 6.2 mg/kg, P less than .001). Serum protein binding of heptabarbital was reduced from 49% in controls to 26% in NS rats. However, the drug concentration in cerebrospinal fluid (CSF) at the pharmacologic endpoint was not significantly different in controls and NS rats (18.9 +/- 1.5 vs. 18.3 +/- 1.4 mg/l). Serum, CSF and the brain contained appreciable concentrations of a metabolite of heptabarbital. To determine if the metabolite contributes to the pharmacologic effect of the parent drug, rats received an i.v. injection of 46, 60 or 100 mg/kg of heptabarbital. Concentrations of heptabarbital in CSF at return of righting reflex (which occurred after 15, 25 and 50 min, respectively) were independent of dose whereas metabolite concentrations increased with increasing dose. Thus, the metabolite of heptabarbital in male rats is pharmacologically inactive.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
98.
Janice C Probst Sarah B Laditka Jong-Yi Wang Andrew O Johnson 《BMC health services research》2007,7(1):40
Background
Travel burden is a key element in conceptualizing geographic access to health care. Prior research has shown that both rural and minority populations bear disproportionate travel burdens. However, many studies are limited to specific types of patient or specific locales. The purpose of our study was to quantify geographic and race-based differences in distance traveled and time spent in travel for medical/dental care using representative national data. 相似文献99.
Francoise Mouchet Valérie Hansen Inge Van Herreweghe Olivier Vandenberg Régine Van Hesse Michèle Gérard Michèle Toppet Maryse Wanlin Véronique Toppet Georges Casimir Dominique Haumont Jack Levy 《Infection control and hospital epidemiology》2004,25(12):1062-1066
OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission. 相似文献
100.
Steven D Billings Shaun V Walsh Cyril Fisher Asma Nusrat Sharon W Weiss Andrew L Folpe 《Modern pathology》2004,17(2):141-149
Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation. 相似文献