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91.
Following aortic valve replacement, up to 5% of patients may develop clinically significant paravalvular leaks. Reoperation is associated with higher mortality and an excess risk of recurrent paravalvular insufficiency. No specifically designed transcatheter device is available for paravalvular leak repair. We describe in a patient with severe aortic prosthetic paravalvular leak the use of an Amplatzer duct occluder device resulting in effective closure and symptomatic improvement.  相似文献   
92.
This study tested the efficacy of a brief preventive intervention for substance use and associated risk behaviors among female adolescent patients of an urban primary care health clinic. We integrated an evidenced-based motivational interviewing (MI) approach with a social network component to develop a 20-minute session, a social network intervention delivered in an MI-consistent style. Female adolescents (N = 28) 14 to 18 years old were recruited, provided consent/assent, were screened, and were randomly assigned to the treatment or control (no treatment) condition. The sample was 82% African American and 18% mixed race, with 32% living below the U.S. poverty line. At 1-month follow-up, teens in the treatment condition reported less trouble due to alcohol use, less substance use before sexual intercourse, less social stress, less offers for marijuana use, and increased readiness to start counseling compared with the teens in the control condition. Results provide support for socially based brief interventions with at-risk urban adolescents.  相似文献   
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In this paper, we discuss the value of an after-death telephone call made by the treating mental health clinician to family members, after the death of a geriatric patient with a psychiatric disorder. We outline the process of the after-death call including the optimal method, nature, and content. We note the psychotherapeutic value of an after-death telephone call in addressing complex emotions, and helping the family to cope with bereavement. We also discuss institutional, legal, and ethical ramifications. We conclude that an after-death call may be of sufficient benefit to be considered as a "best practice" approach in the care of every patient.  相似文献   
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Clear cell carcinoma (CCC) of the ovary is the surface epithelial neoplasm most often confused with primitive germ cell tumors, particularly yolk sac tumor (YST) and dysgerminoma. OCT3/4 has proven to be a sensitive and relatively specific marker for the latter entity, but existing markers for YST are limited. Recent studies suggest that glypican-3 (GPC3), an oncofetal protein expressed in fetal liver and malignant tumors of hepatocytic lineage, is also expressed in germ cell tumors, particularly YST. To investigate whether GPC3 is useful in distinguishing YST from ovarian CCC, we studied the expression of GPC3 in a large series of ovarian neoplasms and compared it to the expression profiles of CK7 and alpha-fetoprotein. Tissue microarrays containing over 400 benign and malignant ovarian neoplasms, including 34 CCCs were stained with monoclonal GPC3 (clone 1G12, Biomosaics, Burlington, VT). These arrays contained a wide assortment of ovarian surface epithelial neoplasms and sex cord stromal neoplasms, as well as germ cell tumors. Full paraffin tissue sections from 32 YSTs and 10 CCCs were also assessed. All but one YST (97%), including those associated with mixed germ cell tumor were positive for GPC3, whereas all teratomas and embryonal carcinomas were negative. Both cytoplasmic and membrane staining were present in the positive cases, with no background staining. The syncytiotrophoblastic cells in the germ cell tumors and placental villi included in the arrays were also positive for GPC3. Most CCCs (83%) were completely negative for GPC3, as were 99% serous, 94% endometrioid, and 100% mucinous tumors. Five CCCs exhibited focal, moderate to strong GPC3 expression and in 2 the expression was focal and weak. All other tissues, including normal ovary were negative for GPC3. GPC3 seems to be a promising diagnostic marker for differentiating YST from ovarian CCC (P < 0.0001). Because GPC3 may be associated with alpha-fetoprotein expression, further studies are required to determine the utility of GPC3 in differentiating YST from CCC with hepatoid differentiation.  相似文献   
99.
The conformational changes in myosin associated with ADP release and their influence on actin sliding velocity are not understood. Following actin binding, the myosin active site is in equilibrium between a closed and open ADP bound state, with the open state previously thought to favor ADP release and thus expected to be favored in faster myosins. However, our recent work with a variety of myosins suggests the opposite, that the open conformation is dominant in slower myosins, which have higher ADP affinities. To test if this correlation holds for fast myosin isoforms, we determined the relationships between conformational pocket dynamics, ADP affinity and velocity of four Drosophila myosins: indirect flight muscle (IFM) myosin (IFI), embryonic muscle myosin (EMB) and two IFI/EMB chimeras. Electron paramagnetic resonance spectra of nucleotide-analog spin probes (SLADP) bound to IFI subfragment-1 in the absence of actin showed a high degree of immobilization, indicating a predominately closed nucleotide pocket. The A·M·SLADP spectra of all four myosins in fibers (actin bound) also indicated an equilibrium favoring the closed conformation with the closed state closing even further. However, the energetics of pocket closure did not correlate with Drosophila myosin actin velocity suggesting our previous model relating pocket dynamics to velocity does not hold for fast myosin isoforms. We conclude that for these fast myosins, and possibly other fast myosins, velocity is controlled by factors other than the ratio of open to closed nucleotide pocket conformation.  相似文献   
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