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41.
Monhegan is an isolated 237-ha island lying 16 km off the coast of Maine. Introduced to the island in 1955, white-tailed deer, Odocoileus virginianus Zimmerman, reached a density of approximately 37/km2 by the mid-1990s. Black-legged ticks, Ixodes scapularis Say, first noticed in the late 1980s, flourished thereafter. Norway rats (Rattus norvegicus Berkenhout) on Monhegan are highly infected with Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt, and Brenner, the agent of Lyme disease. By 1996, 13% of year-round residents had contracted the disease. The community's subsequent decision to eliminate deer from the island provided a unique opportunity to monitor the abundance of vector ticks in response to the complete and permanent removal of the primary hosts of their reproductive stage. With the exception of humans and their dogs and cats, there are no other potential hosts for adult I. scapularis on Monhegan. From November 1996 to March 1999, all deer were removed from the island. Previous annual fall flagging of vegetation from 1990 to 1998 produced 6-17 adult ticks/h, of which 24-41% were infected with the Lyme disease spirochete. During this same period, up to 18 larvae and 4 nymphs were removed per Norway rat live-trapped on the island each July. With the absence of deer in the fall of 1999, both the density of host-seeking adult ticks and infection prevalence rose substantially to 28/h and 75.0%, respectively. By the summer of 2003, however, no sub-adult ticks were found on rats, and that fall, only 0.67 adult ticks/h were flagged. Of the 68 adults collected from 2002 to 2003, 20 (29.4%) were infected. Over this same period, adult tick abundance on a deer-populated, reference island continued to gradually increase.  相似文献   
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The expression of FcγRI, FcγRII, and FcγRIII (the IgG receptors CD64, CD32, CD16) as well as CR3 (the C3bi receptor, CD11b) on monocytes in the blood of patients with systemic lupus erythematosus (SLE) was investigated. The relationship between the receptor expression and the serum immune complex (IC) concentration was analysed. The decrease in mean fluorescence intensity (FI) of the FcγRII of patients' monocytes stained by specific monoclonal antibodies (MoAb IV3) was very close to statistical significance ( P = 0.052). The expression (FI) of CR3 (using MoAb OKM1) on monocytes of patients was also decreased, but not significantly. The detected decrease of FcγRII and CR3 was inversely correlated with the high circulating immune complex level in patients' sera. At the same time, FcγRI expression on SLE monocytes (using MoAb 32) was significantly elevated and this change was in parallel with the serum IC concentration.  相似文献   
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Chronic obstructive pulmonary disease (COPD) is a progressive syndrome of expiratory airflow limitation caused by chronic inflammation of the airways and lung parenchyma. The airway inflammatory response in COPD is initiated by smoking in the overwhelming majority of cases, and chronic exposure to cigarette smoke initiates a series of events that causes damage to central airways, peripheral airways, and terminal airspaces, leading to physiologic and clinical abnormalities. Although COPD shares some clinical features with asthma, another prevalent airway inflammatory disease, there are distinct differences in the phenotypic characteristics of airway inflammation between COPD and asthma. The eosinophil is the most prominent inflammatory cell in asthma, with mast cells, lymphocytes, and macrophages playing important but less prominent roles. In COPD the cellular composition of the airway inflammatory infiltrate differs, with neutrophils, macrophages, and lymphocytes assuming prominence and the eosinophil playing a minor role, except in the setting of exacerbations. The contrasting inflammatory phenotypes of asthma and COPD have important implications for clinical and physiologic manifestations of disease, as well as for therapy.  相似文献   
45.
The age‐dependent penetrance of organ manifestations in Marfan syndrome (MFS) is not known. The aims of this follow‐up study were to explore how clinical features change over a 10‐year period in the same Norwegian MFS cohort. In 2003–2004, we investigated 105 adults for all manifestations in the 1996 Ghent nosology. Ten years later, we performed follow‐up investigations of the survivors (n = 48) who consented. Forty‐six fulfilled the revised Ghent criteria. Median age: females 51 years, range 32–80 years; males 45 years, range 30–67 years. New aortic root dilatation was detected in patients up to 70 years. Ascending aortic pathology was diagnosed in 93 versus 72% at baseline. Sixty‐five percent had undergone aortic surgery compared to 39% at baseline. Pulmonary trunk mean diameter had increased significantly compared to baseline. From inclusion to follow‐up, two patients (three eyes) developed ectopia lentis, four developed dural ectasia, four developed scoliosis, three developed incisional or recurrent herniae, and 14 developed hindfoot deformity. No changes were found regarding protrusio acetabuli, spontaneous pneumothorax, or striae atrophicae. The study confirms that knowledge of incidence and progression of organ manifestations throughout life is important for diagnosis, treatment, and follow‐up of patients with verified or suspected MFS.  相似文献   
46.
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements.  相似文献   
47.
Quality of Life Research - The Adult Social Care Outcomes Toolkit for Carers (ASCOT-Carer), developed in England, measures the effects of long-term care (LTC) services and carer support on informal...  相似文献   
48.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation.  相似文献   
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Aneurysm of sinus of Valsalva dissecting into interventricular septum is a rare entity. We report one such case who was incidentally diagnosed by echocardiography to have this abnormality during evaluation of a clinically suspected isolated aortic regurgitation.KEY WORDS: Aneurysm – dissecting – sinus of Valsalva, Echocardiography  相似文献   
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