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G. Xiromerisiou G. M. Hadjigeorgiou V. Gourbali J. Johnson I. Papakonstantinou A. Papadimitriou A. B. Singleton 《European journal of neurology》2007,14(1):7-11
Mutations in SNCA and LRRK2 genes, encoding alpha-synuclein and leucine-rich repeat kinase 2, respectively, cause autosomal dominant Parkinson's disease (AdPD). The LRRK2 G2019S (c.6055G > A) and R1441G (c.4321C > G) mutations have also been identified in sporadic PD (sPD). We studied 55 unrelated patients with AdPD, 235 patients with sPD, and 235 healthy age- and gender-matched controls all of Greek origin. Patients with AdPD were screened for SNCA and LRRK2 mutations by direct sequencing. SNCA gene dosage analysis was also performed for AdPD using quantitative duplex polymerase chain reaction of genomic DNA. In addition, we investigated the frequency of the LRRK2 G2019S mutation in sPD. We found no missense mutations or multiplications in the SNCA gene. Here we report two novel variants, A211V (c.632C > T) and K544E (c.1630A > G) in LRRK2 gene in two patients with AdPD that was not present in controls. We identified only one patient with sPD (1/235; 0.4%) carrying the G2019S mutation. LRRK2 mutations are present in AdPD and sPD patients of Greek origin. 相似文献
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Two seemingly unrelated events--decentralization of the nursing organization and promotion of nurse executives into patient care services vice presidencies with authority over many departments--prompt the authors to ask the question, "Who is leading the nursing department?" The authors discuss the impact of these trends on the nursing organization and make suggestions for ensuring strong nursing leadership. 相似文献
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Image-directed percutaneous biopsies with a biopsy gun 总被引:3,自引:0,他引:3
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献
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The authors hypothesized that the progesterone component of some hormone replacement therapies in women is detrimental to cognition. A previous study showed that ovariectomy (ovx) in aged rats enhanced spatial working memory and decreased elevated progesterone levels. The current study evaluated whether progesterone administration counteracts these cognitive enhancing effects of ovx. Aged sham and aged ovx rats given progesterone exhibited compromised learning of the working and reference memory components of the task, and made more working memory errors on the latter testing days compared with aged ovx rats not given progesterone. Results suggest that whereas ovx of the aged female rat enhances learning and the ability to handle numerous items of spatial working memory information, progesterone is detrimental to these aspects of performance. These findings may speak to studies in menopausal women which suggest that combination hormone therapies have a negative impact on cognition. 相似文献
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Comparison of the immediate effects of five beta-adrenoreceptor-blocking drugs with different ancillary properties in angina pectoris 总被引:4,自引:0,他引:4
U Thadani C Davidson W Singleton S H Taylor 《The New England journal of medicine》1979,300(14):750-755
We compared the immediate effects of five beta-adrenoreceptor-blocking agents in 16 patients with stable angina pectoris. Acute dose-response studies showed that all five drugs improved exercise tolerance and reduced ST-segment depression, heart rate and blood pressure by a similar degree in comparison with a placebo (P less than 0.01). Near maximum improvement in exercise tolerance occurred when the acute cumulative oral dose had reached 160 mg for propranolol and oxprenolol, 200 mg for metoprolol and tolamolol and 400 mg for practolol. When these drugs were administered as a single doses, increase in walking time before the development of angina and reduction in ST-segment depression, heart rate and systolic blood pressure all occurred within one hour and persisted for eight hours--effects markedly different from the response to a placebo (P less than 0.01). These data show that non-cardioselective agents (propranolol and oxprenolol), cardioselective agents (practolol, metoprolol and tolamolol), as well as drugs with intrinsic sympathomimetic activity (oxprenolol and practolol), were equally effective in the treatment of angina pectoris. 相似文献
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Kroft SH Domiati-Saad R Finn WG Dawson DB Schnitzer B Singleton TP Ross CW 《American journal of clinical pathology》2000,113(3):411-418
Part of the natural history of follicle center lymphoma (FCL) is transformation to a more aggressive neoplasm, almost always a diffuse large B-cell lymphoma. We describe a rare example of a precursor B-lymphoblastic transformation of grade I FCL occurring in a 45-year-old woman 12 years after initial presentation and 3 years after successful treatment for a diffuse large cell transformation. The lymphoblastic lymphoma shared the same immunoglobulin heavy chain gene rearrangement as the FCL as assessed by polymerase chain reaction amplification and direct sequencing, as well as identical kappa light chain gene rearrangements by Southern blot analysis. The immunoglobulin heavy chain variable gene sequences of both tumors showed numerous identical base substitutions compared with germline sequences and 3 additional mutations in the lymphoblastic lymphoma not present in the low-grade FCL. These results indicate origin of the lymphoblastic process from the mature follicle center B-cell clone, rather than divergent origin of the 2 tumors from a common immature B-cell precursor. 相似文献