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991.
The ligament supporting the leading edge of birds' wings is a connective tissue structure with unusual morphologic and elastic features. Its center section is made of a highly extensible composite of elastin and collagen fibers and its two end sections of nearly inextensible pure collagen; these are joined end-to-end in short interdigitating junctions. Substantial forces are transmitted through the junctions showing that collagen and elastin are mechanically connected. The junctions and elastic segment are sufficiently strong that when the intact ligament is maximally strained, the point of failure is commonly in the collagenous segments or their attachments to the tissues of origin or insertion. Here we outline the morphology and describe static force-length properties of this ligament.  相似文献   
992.
Benign mesothelioma of the pleura is a very rare tumor. The cells responsible originate from either the mesothelium or the submesothelium. This is why such tumors are described in the literature as fibroma of the pleura, mesothelial fibroma, localized fibrous mesothelioma and monophasic spindle cell tumor. Their growth, is very slow taking several years or even decades. In contrast to the more common malignant mesothelioma of the pleura, it is not related to asbestos exposure. This report deals with a 47-year-old woman patient with a giant benign mesothelioma of the pleura in the region of the right thorax, which was completely removed by thoracotomy.  相似文献   
993.
BACKGROUND: Stereotaxic core breast biopsy (SCBB) has been proposed as a cost-effective and reliable method of evaluating mammographic lesions. This study evaluates an initial experience with SCBB and assesses the adequacy of the biopsy specimens obtained. METHODS: Two hundred forty-one SCBB were performed on 221 patients during 13 months by four radiologists. Mammograms were assigned a suspicion index on a scale of 1 to 5. One pathologist performed a blinded retrospective review of all SCBB specimens and assigned an adequacy score based on the quality and amount of the tissue present. RESULTS: The majority of SCBB were ordered by general surgeons (67%). A suspicion index score of 3 was assigned to 74% of lesion specimens. Twelve percent of specimens were malignant. Overall SCBB adequacy (score > or = 2) was 77%. Adequacy was present in 74% of benign biopsy specimens as compared with 100% of malignant specimens (p < 0.005). Only 62% of specimens reported as benign without specific features were adequate. There were no differences in adequacy between individual radiologists or during the study period. CONCLUSIONS: SCBB is largely used by surgeons to assess indeterminate mammographic lesions. One of four benign specimens was inadequate. Benign SCBB specimens must be interpreted with caution.  相似文献   
994.
This paper aims to explore the meaning of spirituality in relation to nursing care using concept synthesis. Walker and Avant give three ways in which concept synthesis can occur: discovering new dimensions to old concepts, searching for similarities and discrepancies among sets of related concepts, and observing previously undescribed phenomena. It is the first two of these methods which have been used here. The phenomena that emerged from a reading of the literature around spirituality were meaning, presencing, empathy/compassion, giving hope, love, religion/transcendence, touch and healing. These phenomena were studied in order to sort them into fewer categories. They all appeared to be products of a relationship, some physical (presencing, touch and healing), and others emotional (meaning, empathy/compassion, hope, love, and religion/transcendence). Some of the phenomena appeared to fit in both categories, especially healing, which could be of a physical or emotional/spiritual nature. Once the two main categories had been arranged, it was obvious that a split between psyche and soma was not appropriate for labelling the spiritual dimensions of nursing care, as the original definition of spirit was something which motivated the body. Spiritual care is inseparable from physical, social and psychological care because together they form the whole (Bradshaw 1994 p. 282). The two categories were then collapsed into one and given the label 'connection'.  相似文献   
995.
The authors report on clinical features and mortality rates in a group of 149 patients with apparent idiopathic parkinsonism starting before the age of 40 years. Ten had juvenile parkinsonism (JP; onset before age 21 years) and 139 had young-onset Parkinson's disease (YOPD; onset at age 21 to 40 years). Included were 60 patients originally reported 10 years ago. Fifty percent of the JP group had a positive family history of parkinsonism in a first-degree relative, and clinical presentation was heterogeneous. Mortality risk was threefold that of the normal population. In the YOPD group, the mortality risk was double that of the normal population. Poor initial response to L-dopa was a risk factor for early death. In two previously reported patients, the diagnosis had been changed to multiple system atrophy and Machado-Joseph disease. After a median disease duration of 18 years, cognitive impairment was found in only 19% of YOPD patients (13% of those younger than 60 years and 43% of those 60 years or older). Age was the most important factor for development of dementia, but female sex and positive family history of parkinsonism also had more modest predictive value. After a disease duration of 10 years or less, only 5% of patients were experiencing falls and 30% freezing, but all patients had developed L-dopa-related fluctuations and dyskinesias. The authors conclude that the mortality rate in parkinsonism starting before the age of 40 is increased in comparison to the normal population and is similar to the general Parkinson's disease population. Intellectual function and postural reflexes are usually well preserved for many years despite a long history of parkinsonism and the early and frequent occurrence of treatment complications, provided the patients remain biologically and chronologically young.  相似文献   
996.
Chromogenic hexapeptides Dnp-Ala-Ala/Ser-Phe-Phe-Ala-Arg-NH2 containing a Phe-Phe bond, which is sensitive to aspartic proteinases, were used as substrates for assaying the activity of pepsin, chymosin, and aspergillopepsin A. The assay was performed after the separation of hydrolyzates on SP-Sephadex by measuring at 360 nm the absorbance of the dinitrophenylpeptide lacking the cationic group, which was formed upon the cleavage of the substrate. The kinetic parameters of the hydrolysis of the substrates were evaluated. It is shown that replacing the Ala residue with Ser in the P2 position does not substantially change the kinetic parameters. The substrates were hydrolyzed by pepsin several times faster than by aspergillopepsin A or chymosin. The method is sensitive and enables the activity of aspartic proteinases to be determined easily.  相似文献   
997.
Resistance to organophosphorous insecticides such as malathion, chlorpyrihos, and pyrimiphos-methyl; pyrethroids such as deltametrine and lambda cialotrine; and the propoxur carbamate was determined in 4 strain of Culex quinquefasciatus of the Eastern, Central and Western parts of Cuba. The increase of esterase enzymes was the main mechanism involved in resistance, followed by altered acetylcholinesterase (AChe). Gene frequencies were high for esterases (1), and moderate for acetylcholinesterase (0.52) in the four strains under study, as an average. Bioassays showed resistance to malathion and propoxur. The use of DEF as esterase inhibitor showed that pyrimiphos-methyl was not affected by this mechanism of resistance, and chlorpyriphos was slightly affected. After 5 years of using pyrethroids such as deltametrine and lambda cialotrine, these are still useful agents for the control of C. quinquefasciatus; the alternate use of these and pyrimiphos-methyl or chlorpyriphos could prevent the development of resistance in a short or medium term.  相似文献   
998.
BACKGROUND: Urticaria is a common disease that is always a challenge to the dermatologist due to its evasive etiology. PATIENTS AND METHODS: One hundred and seven chronic urticaria patients were studied. Routine laboratory investigations were performed and Helicobacter pylori (H. pylori) immunoglobulin G (IgG) antibody determinations, autoimmune reactivity, infections, allergies, and hyperreactivities were investigated. RESULTS: Pathologic findings were seen in 92 patients. Concomitant diseases suggesting autoimmune reactivity were detected in nine patients and, in 16 patients, infections including maxillary sinusitis, streptococcal tonsillitis, and tooth infection were found. Elevated total IgE level was detected in 37 out of 75 patients and positive skin prick test results in 47 out of 91 patients. Fifty-five patients had a history of recent dyspeptic symptoms. A diagnosis of adult celiac disease was made in two patients and, additionally, IgA antigliadin antibodies were seen in four patients. H. pylori IgG antibodies were found in 40 out of 107 patients. Active gastritis was verified by esophagogastroduodenoscopy in 30 out of 32 patients with positive Helicobacter staining in 24 samples. An elevated IgE level was detected in 64% of H. pylori-positive and in 39% of H. pylori-negative patients. CONCLUSIONS: In this study, several findings suggesting aberrant immunologic activation were detected in chronic urticaria patients. Inflammation in the gastrointestinal tract, e.g. caused by H. pylori infection, may have an important role in the etiology of chronic urticaria.  相似文献   
999.
BACKGROUND: A bicuspid aortic valve is commonly associated with other levels of left ventricular outflow tract obstruction. Providing the bicuspid aortic valve is competent and nonobstructive, repair of subvalvar or supravalvar stenosis usually focuses on the obstructive lesions, leaving the valve in situ. The aim of this report was to examine the impact of a bicuspid aortic valve on the risk of reoperation for patients undergoing operation for subvalvar or supravalvar aortic stenosis. METHODS: Since 1976, 47 patients with supravalvar or subvalvar aortic stenosis have undergone repair. The median follow-up is 5.1 years (range, 2 months to 20.1 years). Sixteen patients (34%) had a bicuspid aortic valve that was competent and nonobstructive, and 31 (66%) had a tricuspid aortic valve. RESULTS: Reoperation was required in 9 patients (56%) with a bicuspid aortic valve, in each involving aortic valve replacement with an autograft (3), homograft (2), or prosthesis (4). Six patients (19%) with a tricuspid aortic valve required reoperation, yet only 1 required aortic valve replacement. The freedom from valve replacement was 43% (70% confidence interval, 31% to 55%) in the bicuspid aortic valve group versus 100% (70% confidence interval, 94% to 99.5%) in the tricuspid group at 5 years (p = 0.0001). The freedom from any reoperation at 5 years was 43% (70% confidence interval, 31% to 55%) in patients with a bicuspid aortic valve versus 86% (70% confidence interval, 80% to 93%) in the tricuspid group (p = 0.02). CONCLUSIONS: The data suggest that patients with subvalvar or supravalvar aortic stenosis and a bicuspid valve may be better palliated with a more definitive operation such as the Ross or Ross-Konno procedure.  相似文献   
1000.
OBJECTIVES: To assess the in vitro adherence of Candida albicans to heat-cured hard and soft denture-base materials with varying surface roughness, and to observe the effect of a mixed salivary pellicle on candidal adhesion to these surfaces. METHODS: In vitro adhesion assays on heat-cured acrylic resin (Trevalon), Molloplast B and Novus using the type strain of C. albicans (NCPF 3153A). Surfaces for the assays were prepared using clinically appropriate rotary instruments. Unstimulated, pooled and clarified whole saliva was used to assess its effect on adhesion. RESULTS: Significantly greater adhesion of C. albicans to rough rather than smooth surfaces was found (P < 0.001), as well as increased adhesion to the machined soft lining materials compared with acrylic. Pre-coating denture-base materials with saliva reduced candidal adhesion on all materials. CONCLUSIONS: Rough surfaces on denture-base materials promote the adhesion of C. albicans in vitro. However, saliva reduces adhesion of C. albicans and thus diminishes the effect of surface roughness and free surface energy differences between materials.  相似文献   
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