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71.
Tick saliva plays a vital role in blood-feeding, including manipulation of the host response to tick infestation. Furthermore, a diverse number of tick-borne pathogens are transmitted to vertebrate hosts via tick saliva, some of which exploit the immunomodulatory activities of their vector's saliva. We report that salivary gland extracts (SGE) derived from Dermacentor reticulatus adult ticks induce a decrease in the natural killer (NK) activity of effector cells obtained from healthy human blood donors. The decrease was observed with SGE from both female and male D. reticulatus fed for either 3 or 5 days on mice, but no significant effect was observed with SGE from unfed ticks or ticks that had fed for 1 day. These results indicate that the tick anti-NK factor(s) is only active after blood-feeding has commenced. Microscopic examination revealed that the first step of NK activity, namely effector/target cell conjugate formation, was affected by SGE. The observed reduction in conjugate formation occurred when effector (but not target) cells were treated with SGE for 30 min, and the effect persisted after 12 h of treatment. Similar but less potent anti-NK activity was detected for SGE from Amblyomma variegatum and Haemaphysalis inermis. By contrast, SGE derived from Ixodes ricinus and Rhipicephalus appendiculatus female ticks did not decrease NK activity. The apparent absence of such activity in these two important vectors of tick-borne viruses suggests that control of NK cells does not play an important role in promoting virus transmission, at least for these particular species.  相似文献   
72.
PURPOSE: To determine and quantitate radiologic characteristics of inflammatory breast carcinoma and to report clinical and pathologic findings. MATERIALS AND METHODS: A retrospective review of records of 2,733 women who received a diagnosis of breast carcinoma between January 1988 and May 2000 revealed 142 histologically proved inflammatory carcinomas. Analysis included history; findings at physical examination, mammography, and ultrasonography (US); and histologic type of inflammatory carcinoma. RESULTS: At physical examination, skin changes (n = 115, 81%) were the most common findings. A palpable mass was noted in 62% (n = 88), with axillary lymph node involvement in 68% (n = 96) of the carcinomas. Mammography revealed findings in carcinomas: skin thickening, 84% (n = 119); diffusely increased density, 37% (n = 53); trabecular thickening, 81% (n = 115); mass, 16% (n = 23); asymmetric focal density, 61% (n = 87); microcalcifications, 56% (n = 80); nipple retraction, 43% (n = 61); and axillary lymphadenopathy, 24% (n = 34). US showed changes in carcinomas: skin thickening, 96% (n = 136); parenchymal echogenicity changes, 73% (n = 104); dilated lymphatic channels, 68% (n = 96); solid mass, 80% (n = 114); pectoral muscle invasion, 10% (n = 14); focal areas of parenchymal acoustic shadowing, 37% (n = 52); and axillary lymphadenopathy, 73% (n = 104). CONCLUSION: Presence of isolated inflammatory signs is sufficient to suggest inflammatory breast carcinoma clinically. Inflammatory breast carcinoma has a mammographic pattern of inflammatory changes, such as skin thickening and stromal coarsening and/or diffusely increased breast density with or without an associated mass and/or malignant-type microcalcifications. US is helpful not only in depiction of masses masked by the edema pattern but also in demonstration of skin and pectoral muscle invasion and axillary involvement.  相似文献   
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Adductor paralysis or the pathologies occurring after laryngeal surgery such as scarring or atrophy of the vocal cords cause glottic insufficiency during phonation. Injection laryngoplasty has been a widely accepted technique due to lower morbidity of the procedure and the applicability via endoscope in the treatment of these pathologies. Various materials have been used in injection laryngoplasty. The primary expectations in these techniques are the persistence of injected material long enough, without resorbtion or any cause of serious tissue response and having beneficial effects in reinforcing the glottic tissue. In the present study, we used large molecular-sized calcium hydroxyl-apatite (CaHA) particles in injection laryngoplasty to observe the effects of the material in the laryngeal tissues under the light microscopic examination. The study was performed on 12 rabbits in four groups. After injecting Ca10 (PO4)6(OH)2 (Coaptite®) into their vocal folds, the rabbits were killed at certain intervals, in the 1st week (group 1) in the 1st month (group 2) in the 3rd month (group 3) and in the 6th month (group 4). Larynges were removed and processed for light microscopic observations. Our observations revealed that this material induced the new cartilage formation without a serious tissue response in the larynges. Formation of a new cartilage tissue was the most significant, but an unexpected outcome of the study. The injected material inducing a neocartilage formation without any tissue reaction persisted long enough in the laryngeal tissues. Although neocartilage formation may interfere the vocal fold vibrations, providing glottic closure in the phonation with a durable material will be an important gain.  相似文献   
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Physical exercise has influence on all organs except its effects on the central nervous system have not been fully elucidated. This study attempts to determine whether the degree of training could affect the response to physical stress by comparing the three groups of males in different levels of the physical fitness. Serum samples from high (n = 11), moderate (n = 10), and low physical activity sportsmen (n = 10) were collected to determine nitrite/nitrate levels before and after carrying out an anaerobic maximal exercise test. An "oddball paradigm" of auditory stimuli was used to evoke the N200 and P300 before and after the exercise. The amplitude of the N200 decreased significantly after anaerobic maximal exercise compared to the values of the recorded pre-exercise at Fz area in high physical activity group. There was a negative correlation between event-related potentials component and both nitrite/nitrate serum level changes and the heart rate changes in low physical activity subjects. However, in high and moderate physical activity groups, these relationships were positive.  相似文献   
78.
We report a 9-month-old boy who presented with a hard paratesticular mass. Clinical and ultrasound findings were highly suggestive of malignancy and orchidectomy was performed. Histology confirmed the unexpected diagnosis of meconium periorchitis, a rare, benign condition resulting from intrauterine bowel perforation.  相似文献   
79.
Primary extragenital leiomyosarcoma is rarely found in pelvic localization. A 33-year-old multiparous woman who had recurrent low-grade leiomyosarcoma presented with the complaints of dyspareunia, pelvic pain and gait disturbance. Her past medical history revealed she had been subjected to maximal excision of a paravaginal mass by using vaginal and suprapubic transverse incision three years before. The pathology report showed that she had leiomyoma. Three years after the initial surgery, a paravaginal fixed mass was observed at the initial tumor bed and removed by the perineal approach. The histological examination of the specimen revealed a low grade leiomyosarcoma. She was discharged from hospital without any complications.  相似文献   
80.
An infant with pentalogy of Cantrell and limb defects diagnosed prenatally   总被引:1,自引:0,他引:1  
We present a case of pentalogy of Cantrell which was diagnosed prenatally on routine ultrasound examination. There were several associated limb defects. We discuss the differential diagnosis and conclude that our case probably had a variant form of this syndrome.  相似文献   
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