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排序方式: 共有450条查询结果,搜索用时 15 毫秒
441.
442.
Papillomas in the oral mucosa compatible with focal epithelial hyperplasia are reported in two chimpanzees. The lesions were studied by light and electron microscopy. Virus particles were not observed. The literature dealing with focal epithelial hyperplasia in humans and other animals is reviewed. 相似文献
443.
While devising a protocol for the isolation of chick crypt cells infected with Eimeria necatrix, it was observed that infected cells were readily lysed by 0.25% trypsin. Time-course studies at 17 C with 5.5 × 105 cells at 96 hr postinfection revealed that 0.001% trypsin effectively lysed >90% of infected cells within 10 min. Uninfected crypt cells were not lysed under these conditions. To determine the site of action of trypsin, the plasma membrane proteins from trypsin-treated and untreated infected cells were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. While the major proteins were unaffected by the trypsin treatment, some minor changes were noted: (1) three components (~-60, ~-52, and ~-20 KDa) were trypsin sensitive and (2) a new band (~-42 KDa) appeared in the membrane of trypsin-treated infected cells. Previously, it was found that the plasma membrane of infected cells, in contrast to uninfected cells, accumulated gel-phase lipid (J. E. Thompson, M. A. Fernando, and J. Pasternak, Biochimica et Biophysica Acta555, 472–487, 1979). Here, it was examined whether trypsin would perturb the physical state of the plasma membrane of infected cells. Both X-ray diffraction patterns and transition temperature studies revealed no difference between membranes from untreated and trypsin-treated infected cells. Thus, “trypsin sensitivity” may be a secondary phenomenon that is due primarily to the cellular leakiness that accompanies the accumulation of gel-phase lipid in the plasma membrane of infected cells. The uptake of trypsin may stimulate the release of catabolic enzymes that, consequently, lyse an infected cell. 相似文献
444.
《Theriogenology》2016,85(9):1611-1619
The study uniquely described the clinical value of transabdominal ultrasonography for monitoring features characterizing the estrous cycle in female cheetahs (Acinonyx jubatus). The reproductive tracts of 21 female, nulliparous, and relatively aged (median: 11 and interquartile range: 9.25–14 years) captive cheetahs resident on two sites in Namibia were assessed by transabdominal ultrasound. Subsequently, the ovarian findings on ultrasound were compared with direct visualization while performing laparoscopic sterilization. A combination of these observations supported by concurrent sampling for vaginal cytology and serum progesterone concentrations defined the estrous status of individual animals. At one site, six cheetahs had been implanted with the GnRH agonist, deslorelin as a contraceptive at least once within the preceding 11 years. On ultrasound, 31 uterine horns and 35 ovaries with discernible structures on 28 (86%) were visualized in the 21 cheetahs. The uterine body was difficult to visualize because of its intrapelvic location. Eleven of 19 uteri (58%) visualized showed endometrial edema suggestive of estrogenization. The uteri of four cheetahs (19%) showed evidence of mild cystic endometrial hyperplasia. Paraovarian cysts were seen on ultrasound (n = 21) and laparoscopy (n = 26) in 16 (76.2%) and 18 (85.7%) cheetahs, respectively. Ovarian volumes obtained from ultrasonographically determined dimensions predicted cyclic activity. Laparoscopy showed that 19 ovaries had discernible follicular structures. In the study population, 10 (47.6%) cheetahs were in proestrus or estrus; none in the luteal phase; and 11 (52.4%) in anestrus. Transabdominal ultrasound, in combination with serum progesterone concentrations and vaginal cytology, was used with acceptable accuracy to assess cyclic ovarian activity in captive cheetahs. A considerable proportion of this aged population showed ovarian activity and the prevalence of paraovarian cysts was notable. A history of prior deslorelin treatment was not associated with either reproductive activity or uterine pathology. 相似文献
445.
《Endocrine practice》2021,27(11):1077-1081
ObjectiveMedullary thyroid carcinoma (MTC) can be very aggressive, and early diagnosis is based on routine measurement of serum calcitonin (CT) and RET genetic testing for hereditary forms. Basal serum CT (bCT) concentrations are useful in the early detection of MTC, although it is still unclear whether they can also be used for the differential diagnosis between MTC and C-cell hyperplasia (CCH). Since false-positive results can be obtained with the basal measurement of CT, a provocative test to evaluate stimulated CT (sCT) is often needed. The objective of this study was to investigate the utility of a calcium gluconate test for CT in distinguishing MTC from CCH, a precancerous condition in hereditary forms of MTCs but with unclear significance in sporadic MTCs.MethodsA total of 74 patients underwent the calcium loading test before thyroidectomy, and bCT and sCT levels were compared with histologic results by receiver operating characteristic plot analyses.ResultsA peak CT level of 388.4 pg/mL after stimulation with calcium gluconate was able to significantly distinguish patients with MTC from those with CCH and those without C-cell pathology, with 81.8% sensitivity and 36.5% specificity. A bCT level of 16.1 pg/mL was able to distinguish between these 2 groups of patients with a sensitivity of 90%.ConclusionHigh-dose calcium test is an effective procedure that can be applied for differential diagnosis of MTC and CCH. Reference ranges for calcium sCT levels and CT thresholds in different groups of patients have been identified. 相似文献
446.
《Cell metabolism》2021,33(8):1640-1654.e8
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447.
448.
谷丙甘氨酸胶囊治疗前列腺增生32例临床疗效观察 总被引:1,自引:0,他引:1
目的 :观察治疗前列腺疾病药物谷丙甘氨酸胶囊 (安尿通胶囊 )的临床疗效。方法 :32例前列腺增生患者 ,口服谷丙甘氨酸胶囊 ,每次 82 0mg ,tid ,一个疗程后观察排尿症状进行疗效判定。结果 :32例患者经谷丙甘氨酸胶囊治疗一个疗程后 ,显效 9例 ,有效 14例 ,无效 9例 ,总有效率 72 %。 32例患者用药期间均未发生不良反应。结论 :谷丙甘氨酸胶囊是安全有效的治疗前列腺增生的药物。 相似文献
449.
Sophie Dream Sandra Park Tina W. Yen William Rilling Lisa Rein Kara Doffek James W. Findling Steven B. Magill Srividya Kidambi Douglas B. Evans Tracy S. Wang 《Endocrine practice》2022,28(3):276-281
ObjectiveIn patients with primary aldosteronism, adrenal venous sampling (AVS) is performed to determine the presence of unilateral or bilateral adrenal disease. During AVS, verification of catheter positioning within the left adrenal vein (AV) and the right AV by comparison of AV and inferior vena cava (IVC) cortisol levels can be variable. The objective of this study was to determine the utility of AV epinephrine levels in assessing successful AV cannulation.MethodsThis was a single institution, retrospective review of patients who underwent AVS with cosyntropin stimulation for primary aldosteronism between 2009 and 2018. Successful cannulation of the AV was defined by an AV/IVC cortisol ratio selectivity index (SI) ≥3:1. Epinephrine thresholds to predict catheter placement in the AV were determined using logistic regression. The calculated epinephrine thresholds were compared with previously published thresholds.ResultsAVS was performed on 101 consecutive patients and, based on the SI, successful cannulation of the left AV and right AV occurred in 98 (97%) and 91(90%) patients, respectively. The calculated optimal epinephrine threshold to predict AV cannulation was 364 pg/mL (sensitivity, 92.1%; specificity, 94.6%) and the calculated optimal AV/IVC epinephrine ratio threshold was 27.4, (sensitivity, 92.1%; specificity, 91.3%). Among the 14 patients with failed AV cannulation, 3 patients would have been considered to have successful AVS using AV epinephrine levels >364 pg/mL and AV/IVC epinephrine ratio >27.4 thresholds.ConclusionObtaining 2 right AV samples routinely as well as AV and IVC epinephrine levels during AVS could prevent unnecessary repeat AVS in patients with failed AV cannulation based on cortisol-based SI <3:1. 相似文献