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101.
The existence and characteristics of bone marrow T-cell progenitors have not yet been established in man. Several pieces of evidence such as the reconstitution of certain immunodeficiencies by bone marrow graft suggest that T-cell precursors are present in the bone marrow. We report the growth of T-cell colonies from bone marrow populations using PHA-stimulated lymphocyte-conditioned medium containing T-cell growth factor (TCGF). Rosetting experiments and complement-dependent cytotoxicity assays with monoclonal antibodies indicate that the bone marrow T colony-forming cells (T-CFC) are E- OKT 3- and la+, i.e., immature progenitors. The colonies derived from these cells have the phenotype of mature T cells: E + OKT 3 + la- with either helper (OKT 4+) and suppressor (OKT 8 +) antigens. These results suggest that a thymic microenvironment may not be necessary for the in vitro proliferation and differentiation of the T-cell lineage in adult humans. These methodologies may permit direct investigation of early phenomena concerning the T-cell lineage, such as the acquisition of self-tolerance, the formation of a repertoire of specificities, and the HLA restriction phenomena that we believe takes place before the thymic maturation. 相似文献
102.
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography. 相似文献
103.
Background
The current status of radioiodine-131 (RaI) dosimetry for Graves' hyperthyroidism is not clear. Recurrent hyperthyroidism and iatrogenic hypothyroidism are two problems which interact such that trying to solve one leads to exacerbation of the other. Optimized RaI therapy has therefore begun to be defined just in terms of early hypothyroidism (ablative therapy) as physicians have given up on reducing hypothyroidism.Methods
Optimized therapy is evaluated both in terms of the greatest separation of cure rate from hypothyroidism rate (non-ablative therapy) or in terms of early hypothyroidism (ablative therapy) by mathematical modeling of outcome after radioiodine and critically discussing the three common methods of RaI dosing for Graves' disease.Results
Cure follows a logarithmic relationship to activity administered or absorbed dose, while hypothyroidism follows a linear relationship. The effect of including or omitting factors in the calculation of the administered I–131 activity such as the measured thyroid uptake and effective half-life of RaI or giving extra compensation for gland size is discussed.Conclusions
Very little benefit can be gained by employing complicated methods of RaI dose selection for non-ablative therapy since the standard activity model shows the best potential for cure and prolonged euthyroidism. For ablative therapy, a standard MBq/g dosing provides the best outcome in terms of cure and early hypothyroidism. 相似文献104.
105.
通常认为异体血液采集的献血者发生不良反应和损伤的发生率低,但自体献血者不良反应发生率的数据则自相矛盾,单采不良反应的发生率和预测献血者反应的因素还知之甚少。 本文分析了作者输血中心1998年1月到2001年6月记录的血液和单采献血者的所有不良反应。作者对发生不良反应与未报告任何不良反应的献血者之间的人口统计学和身体特征进行比较,以便确定不良反应预测因素的存在。 相似文献
106.
107.
A case who was suffering from abdominal pain and chronic diarrhea refered to Isfahan Health Training and Research Center, Institute of Public Health. Current treatments for chronic diarrhea incloding a traial of gluten fre diet were performed but these were not effective because he was infected by Dicrocoelium dentriticum. Then he was cured with parasitic treatment. 相似文献
108.
109.
Background
Linguatula serrata, one of the parasitic zoonoses, inhabits the canine respiratory system (final hosts). The objective of this study was to determine the prevalence rate of L. serrata nymphs in mesenteric lymph nodes (MLNs) of cattle and buffaloes (intermediate hosts) that were processed in the Ahvaz, Iran abattoir.Methods
During November 2010 to March 2011, 223 animals (119 cattle and 104 buffaloes), in different sex and three age groups (<2, 2–< 3 and 3-> 3 years old) were sampled randomly at Ahvaz abattoir. Up to 35 grams of their mesenteric lymph nodes were examined separately for nymphal stages of L. serrata by digesting the samples with acid- pepsin method, collected the nymphs and counted under stereomicroscope.Results
Overall 37(16.6%) of 223 animals were infected with L. serrata nymphs in their mesenteric lymph nodes. Prevalence of the infection in cattle and buffaloes were 16.8% and 16.3% respectively. The number of collected nymphs of MLNs was ranged from 1 to 16. No significant differences were seen in the infection rates between males and females (sexes) and age groups in the cattle and buffaloes (P <0.05).Conclusion
Linguatula serrata has an active life cycle in the studied area and a zoonotic potential for transmission between animal and human. Avoiding use of raw MLNs to dogs can help reduce the infection. 相似文献110.
The objective of the present study was to describe the relationship between some reproductive parameters, hormonal levels, and some biochemical properties of blood serum in rams under the Afyon province conditions. The total protein and globulin were positively (P?<?0.01) correlated with sperm motility and sperm concentration in all of rams. Total lipid was negatively (P?<?0.05) correlated with sperm motility and concentration in Daglic, and it was positively (P?<?0.01) correlated with percentage of abnormal spermatozoa in Chios rams. Total lipid and cholesterol was positively (P?<?0.01) correlated with triiodothyronine in all of rams and was negatively (P?<?0.05) correlated with testosterone in Daglic rams. Percentage of abnormal spermatozoa were negatively (P?<?0.01) correlated with alanine amino transaminase (ALT) level, but were positively (P?<?0.01) associated with aspartate amino transaminase (AST) level and AST/ALT ratio in all of rams. 相似文献