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71.
72.
An adult female Oustalet's chameleon was examined to determine the cause of a fluctuant enlargement of the right superior eyelid. Surgical exploration of the subcutaneous tissues of the eyelid revealed live microfilarial parasites, which were identified later as Foleyella sp. These parasites, although seldomly reported, are fairly common in imported chameleons and can be detected during examination of blood smears. Surgical removal continues to be the treatment of choice for these parasites, because the efficacy and safety of many new anthelmintic agents have not been determined for use in chameleons.  相似文献   
73.
When two identical stimuli are presented from two loudspeakers with a brief delay between them, a single image is heard near the source of the leading sound. The delayed sound or echo appears to be suppressed whereas the preceding sound determines perceived location, hence the name, the precedence effect. This study investigated normal-hearing listeners' sensitivity to changes in the intensity of the lagging sound. Pairs of 2-ms white noise bursts, with a 2-ms delay between the onsets of lead and lag, were presented from two loudspeakers 45 degrees left and right of midline in an anechoic chamber. A 2AFC procedure was used to test discrimination of intensity changes in the lead, lag, and both sounds together. The untreated results showed discrimination to be poorest for changes in the lag stimulus. However, when the intensity differences were transformed into predictions of equivalent monaural level based on KEMAR measurements and binaural loudness summation, discrimination for the lag was equal to the other two conditions. A follow-up experiment found that listeners were highly sensitive to the presence of the lag, more sensitive than would be predicted from loudness changes. It is concluded that the precedence effect does not consist of a general suppression or attenuation of the lagging sound, but rather that suppression may be limited to directionality cues.  相似文献   
74.
Picrotoxin (50 microM) elicited rhythmic synchronized bursting in CA3 pyramidal cells in guinea pig hippocampal slices. Addition of the selective group I metabotropic glutamate receptor (mGluR) agonist (S)-3,5-dihydroxyphenylglycine (25 microM) elicited an increase in burst frequency. This was soon followed by a slowly progressive increase in burst duration (BD), converting the brief 250-520 ms picrotoxin-induced synchronized bursts into prolonged discharges of 1-5 s in duration. BD was significantly increased within 60 min and reached a maximum after 2-2.5 h of agonist exposure. The protein synthesis inhibitors anisomycin (15 microM) or cycloheximide (25 microM) significantly impeded the mGluR-mediated development of the prolonged bursts; 90-120 min of agonist application failed to elicit the expected burst prolongation. By contrast, the mGluR-mediated enhancement of burst frequency progressed unimpeded. Furthermore, protein synthesis inhibitors had no significant effect on the frequency or duration of fully developed mGluR-induced prolonged discharges. These results suggest that the group I mGluR-mediated prolongation of synchronized bursts has a protein synthesis-dependent mechanism.  相似文献   
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RK Mittal 《Canadian Metallurgical Quarterly》1998,33(11):65-6, 69-70, 73-5 passim
Diaphragmatic hernias are among the most common abnormalities of the gastrointestinal tract. Those with significant paraesophageal features may require surgical intervention to prevent potentially lethal complications. By contrast, 90% of patients with sliding hiatal hernias respond favorably to behavior modification and antisecretory drug therapy.  相似文献   
78.
PURPOSE: Great interest in predictive testing for hereditary cancer syndromes has been reported. Prior research has focused on testing for specific hereditary syndromes and/or among individuals at high risk for positive carrier status. Given anticipated expansion of both the range of hereditary syndromes for which testing will be available, as well as the clinical settings in which testing will occur, assessment of interest in hereditary cancer risk testing and notification in the general public is warranted. METHODS: As part of an annual statewide telephone survey, adults' (N = 654) interest in hereditary cancer risk testing and notification was assessed. RESULTS: Interest in both risk testing (82%) and risk notification (87%) was high. Logistic regression analyses indicated that disinterest in risk notification was associated with female sex, performance of fewer health protective behaviors, and better perceptions of personal health. Disinterest in risk testing was associated with these same variables as well as older age, less concern over developing cancer, and a more extensive history of cancer in first degree relatives. CONCLUSION: In the absence of risk-reducing behaviors with demonstrable efficacy, hereditary risk testing programs may have difficulty attracting the interest of those at greatest risk for carrier status. In contrast, many individuals at low risk for positive carrier status might seek testing, perhaps as a means of seeking reassurance regarding their low hereditary risk.  相似文献   
79.
Bone marrow necrosis (BMN) is a relatively rare entity and has been associated with a poor prognosis. It is most commonly found in patients with neoplastic disorders, severe infections and sickle cell anemia. An unusual case of antiphospholipid syndrome (APS) with extensive bone marrow necrosis is described in a 27 year old woman. The patient presented with severe pancytopenia, some cognitive impairment resulting from a previous cerebrovascular accident, fever, hypertension, dyspnoea, tachycardia, hepatosplenomegaly, and vaginal bleeding. Her laboratory findings included a strongly positive Coombs' test (anti-IgG and anti-C3d), a prothrombin time of 23 seconds and an activated partial thromboplastin time of 45 seconds. Anticardiolipin antibody tests were positive. Antinuclear and anti-DNA antibodies were negative but the anti-SM test was positive. A bone marrow biopsy specimen was reported as showing extensive necrosis. The patient was treated with steroids, transfusion, and plasma exchange with some clinical improvement but her pancytopenia did not respond and necessitated frequent transfusions. This case lends further support to the association between APS and BMN.  相似文献   
80.
Intracellular localization studies of various potyvirus proteins have been made in hope of finding clues to their function(s). Immunocytological studies localized many of the tobacco etch virus (TEV)-encoded proteins in infected cells. We used antiserum against the nonstructural P3 protein of TEV to determine the subcellular location of the P3 protein in ultrathin sections of virus-infected cells. Immunogold labeling with the antiserum showed labels associated with nucleoli, nuclei, or NIs, Absorption of antiserum with purified NIs or P3 protein resulted in no labeling. TEV NIs are known to contain a bifunctional genome-linked protein-viral proteinase (NIa-VPg) and RNA-dependent RNA polymerase (NIb). It appeared that the TEV P3 protein was a third nonstructural viral protein of NIs of TEV if the NIa-VPg is considered one protein. The presence of P3 in NIs was also supported by Western blot assays. P3 protein in the nucleolus and nucleus could indicate that it, too, is involved in early stages of viral replication.  相似文献   
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