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101.
In this paper we report the cloning of the chicken preprothyrotropin-releasing hormone (TRH) cDNA and the study of its hypothalamic distribution. Chicken pre-proTRH contains five exact copies of the TRH progenitor sequence (Glu-His-Pro-Gly) of which only four are flanked by pairs of basic amino acids. In addition, the amino acid sequence contains three sequences that resemble the TRH progenitor sequence but seem to have lost their TRH-coding function during vertebrate evolution. The amino acid sequence homology of preproTRH between different species is very low. Nevertheless, when the tertiary structures are compared using hydrophobicity plots, the resemblance between chicken and rat prepro-TRH is striking. The cloning results also showed that the chicken preproTRH sequence includes neither a rat peptide spacer 4 (Ps4) nor a Ps5 connecting peptide. Comparison of the cDNA sequence with the chicken genome database revealed the presence of two introns, one in the 5' untranslated region, and another downstream from the translation start site. This means that the gene structure of chicken preproTRH resembles the gene stucture of this precursor in mammals. Based on the cDNA sequence, digoxigenin-labelled probes were produced to study the distribution of preproTRH in the chicken brain. By means of in situ hybridization, preproTRH mRNA was detected in the chicken paraventricular nucleus (PVN) and in the lateral hypothalamus (LHy).  相似文献   
102.
A 5-year-old girl from Rwanda was referred to our pediatric oncology department with severe bilateral proptosis and a bloody, necrotic chemosis of the conjunctiva and infraorbital tissues. Furthermore, she presented with a left facial paresis, hemorrhagic gingiva, epistaxis, and bloody tears. There was a 3-month history of pancytopenia. Investigations that included a complete blood count, peripheral blood smear, and bone marrow aspirate, were conclusive for the diagnosis of acute myeloid leukemia.  相似文献   
103.
104.
Sensory information is critical to correct performance errors online during the execution of complex tasks and can be complemented by augmented feedback (FB). Here, 2 groups of participants acquired a new bimanual coordination pattern under different augmented FB conditions: 1) visual input reflecting coordination between the 2 hands and 2) auditory pacing integrating the timing of both hands into a single temporal structure. Behavioral findings revealed that the visual group became dependent on this augmented FB for performance, whereas the auditory group performed equally well with or without augmented FB by the end of practice. Functional magnetic resonance imaging (fMRI) results corroborated these behavioral findings: the visual group showed neural activity increases in sensory-specific areas during practice, supporting increased reliance on augmented FB. Conversely, the auditory group showed a neural activity decrease, specifically in areas associated with cognitive/sensory monitoring of motor task performance, supporting the development of a control mode that was less reliant on augmented FB sources. Finally, some remnants of brain activity in sensory-specific areas in the absence of augmented FB were found for the visual group only, illustrating ongoing reliance on these areas. These findings provide the first neural account for the "guidance hypothesis of information FB," extensively supported by behavioral research.  相似文献   
105.
The continuing organ shortage requires evaluation of all potential donors, including those with malignant disease. In the United States, no organized approach to assessment of risk of donor tumor transmission exists, and organs from such donors are often discarded. The ad hoc Disease Transmission Advisory Committee (DTAC) of the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) formed an ad hoc Malignancy Subcommittee to advise on this subject. The Subcommittee reviewed the largely anecdotal literature and held discussions to generate a framework to approach risk evaluation in this circumstance. Six levels of risk developed by consensus. Suggested approach to donor utilization is given for each category, recognizing the primacy of individual clinical judgment and often emergent clinical circumstances. Categories are populated with specific tumors based on available data, including active or historical cancer. Benign tumors are considered in relation to risk of malignant transformation. Specific attention is paid to potential use of kidneys harboring small solitary renal cell carcinomas, and to patients with central nervous system tumors. This resource document is tailored to clinical practice in the United States and should aid clinical decision making in the difficult circumstance of an organ donor with potential or proven neoplasia.  相似文献   
106.

Purpose  

To determine the ability of 3.0T magnetic resonance (MR) imaging to identify partial tears of the anterior cruciate ligament (ACL) and to allow distinction of complete from partial ACL tears.  相似文献   
107.
Aims: A significant number of patients with pulmonary hypertension are resistant to medical therapy. We wanted to evaluate whether the modified technique of stent fenestration of the interatrial septum would be feasible and safe, and offer clinical benefit. Methods and Results: The medical records of all patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension who underwent a stent fenestration of the interatrial septum between 2001 and 2008 were reviewed. In all fifteen patients (12 female, mean age 48.2 ± 20.5 years) a successful fenestration procedure could be performed. Median follow‐up time between diagnosis and fenestration was 2.3 years (range from 0.5 to 18.6 years). Mean event free survival since diagnosis and after septostomy was 9.8 ± 2.9 and 3.2 ± 0.8 years, respectively. When one extreme outlier was excluded, the 6 min walk distance improved significantly from 309 ± 69 m immediately before fenestration to 374 ± 84 m, 3–4 months after fenestration (n = 8, paired t‐test, P = 0.03). No stent occlusion occurred. Conclusion: The modified stent fenestration technique is feasible and safe in patients with severe pulmonary hypertension. In a selected group of patients, functional capacity might improve although disease progression continues. © 2008 Wiley‐Liss, Inc.  相似文献   
108.
Swine influenza viruses (SIVs) of H1N1, H3N2, and H1N2 subtypes, with antigenically different hemagglutinins, are currently cocirculating in pigs in Europe. This study aimed to determine whether the hemagglutination inhibition (HI) test, which is the primary serological test for SIV, is sufficiently specific to discriminate between infections with the three subtypes. In experiment 1, pigs were consecutively inoculated with European H1N1, H3N2, and H1N2 SIVs by the intranasal route, or with the respective subtypes only. In a second experiment, a commercial, inactivated H1N1- and H3N2- based SIV vaccine was administered once to pigs previously infected with one to three SIV subtypes or to influenza-naive pigs. Sequential serum samples were examined in HI and virus-neutralizing (VN) tests to the three strains used for pig inoculations. Of the 160 sera collected after infection with one or two SIV subtypes, only 8 showed cross-reactive antibodies to the remaining subtype(s) in the HI test, and 11 in the VN test. Consecutive inoculations with H1N1 and H1N2 or vice versa were followed by a significant rise in preexisting antibody titers to the first subtype after the second inoculation. When dually infection-immune pigs were inoculated with the third, remaining SIV subtype, nasal virus excretion was undetectable or reduced and the serological response was absent to moderate. A single vaccination of infection-immune pigs resulted in a dramatic rise in HI and VN antibody titers to any of the previously encountered subtypes, whereas SIV-naive pigs barely seroconverted. Most important, pigs previously infected with H1N1 but not with H1N2 developed crossreactive antibodies to H1N2 after the vaccination. In conclusion, the HI test remains adequate for the differential diagnosis of infections with H1N1, H3N2, and H1N2 in European swine populations if it is properly used and if the SIV vaccination status is taken into account.  相似文献   
109.
Although cytogenetic analysis advanced the understanding of the pathogenesis of primary non-Hodgkin lymphoma and led to improved clinical management, there have been no large cytogenetic studies of post-transplant lymphoproliferative disorder (PTLD). We examined the karyotypes of 36 PTLD cases and correlated them with clinical, laboratory, and pathologic findings. The cases included 2 early lesions, 13 polymorphic PTLDs, and 21 monomorphic PTLDs (18 B-cell and 3 T-cell proliferations). Cytogenetic abnormalities were identified in 72% of monomorphic B-cell PTLDs and in all T-cell PTLDs, but in only 15% of polymorphic PTLDs and in no early lesions. The most frequent clonal abnormalities in monomorphic PTLD were trisomies 9 and/or 11 (5 cases), followed by rearrangements of 8q24.1 (4 cases), 3q27 (2 cases), and 14q32 (2 cases). MYC rearrangement (8q24.1) and T-cell-associated chromosomal abnormalities correlated with poor outcome and short survival. PTLD with trisomy 9 and/or 11 developed early after transplant, presenting as Epstein-Barr virus-positive large B-cell lymphoma with prolonged survival.  相似文献   
110.
We present the first clinical report of a Staphylococcus pseudintermedius infection in a human. Biochemically, S. pseudintermedius can be easily misidentified as S. aureus. Therefore, the final microbiological identification requires the combination of phenotypic and genotypic tests.  相似文献   
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