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61.
The proximal and distal growth plates of the principal long bones do not contribute equally to longitudinal growth. Most forelimb elongation occurs at the shoulder and wrist, while most hindlimb growth occurs at the knee. This study examined whether insulin‐like growth factor‐I (IGF‐I), a potent growth regulator, could underlie this variation via differential receptor expression. The spatiotemporal distribution of the IGF‐I receptor (IGF‐IR) was mapped in hindlimb growth plates (overall and within regional zones) from immature mice using immunohistochemistry. Growth activity was assessed by size/morphology of the growth plate and proliferating cell nuclear antigen (PCNA) expression. Both IGF‐IR and PCNA staining declined considerably with age in the proximal femur and distal tibia (hip and ankle), but expression remained high in the more active distal femur and proximal tibia (knee) throughout growth. Growth plate size decreased with age in all sites, but the absolute and relative decline in IGF‐IR in the hips and ankles of older mice indicated a site‐specific loss of IGF‐I sensitivity in these less active regions. These results suggest that regulation of the IGF‐IR may at least partially mediate differential long bone growth, thereby providing a local mechanism for altering skeletal proportions absent modification of systemic hormone levels. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
62.
Dai L  Lü XH  Li ZH  Li R  Liu H  Liu YL  Hui YZ 《中华病理学杂志》2004,33(2):140-142
目的 探讨肾上皮性肿瘤的诊断及鉴别诊断。方法 对91例具有较完整病理资料的肾上皮性肿瘤进行了常规组织学观察,Mowy胶状铁染色及CD10、细胞角蛋白(CK)7、波形蛋白免疫组织化学染色。结果 91例肾上皮性肿瘤中肾透明细胞癌78例,占86%;肾乳头状癌8例,占9%;肾嫌色细胞癌4例,占4%;肾嗜酸细胞腺瘤1例,占1%。78例肾透明细胞癌中CD10、波形蛋白阳性分别为63例(81%)和69例(88%),主要表现为细胞膜阳性。74/78肾透明细胞癌CK7呈阴性,17/17 Mowy胶状铁染色阴性或呈灶状粗颗粒。肾嫌色细胞癌4例,CK7均呈胞膜阳性;Mowy胶状铁染色表现为胞质内蓝色细网状;4例CD10肿瘤细胞膜均阴性,波形蛋白阴性。肾嗜酸细胞腺癌1例CD10,CK7,波形蛋白,Mowy胶状铁染色均为阴性或不特异。结论 在常规诊断肾上皮性肿瘤有困难时免疫组织化学CD10,CK7,波形蛋白染色以及Mowy胶状铁染色对鉴别诊断有帮助。  相似文献   
63.
目的 探讨蝶窦垂体腺瘤(sphenoid sinus pituitary adenoma,SSPA)的临床病理特征,提高对蝶窦垂体腺瘤的认识和病理诊断水平.方法 对12例SSPA进行临床、组织病理学和SP法免疫组化染色(PRL、hGH、ACTH、LH、TSH、FSH等).结果 12例SSPA,男5例,女7例,年龄39~66岁,平均48.4岁,中位年龄55.5岁.其中原发于蝶窦和原发于垂体窝侵至蝶窦者各6例,原发于蝶窦者年龄较原发于垂体窝者偏大.临床症状多样.镜下,原发于蝶窦的垂体腺瘤的形态学与蝶鞍垂体腺瘤相同;SSPA可伴有较明显的慢性炎症细胞浸润(2/12,16.67%).10例行免疫组织化学染色的结果,瘤细胞PRL阳性6例;瘤细胞各项标记物均阴性2例;瘤细胞ACTH阳性、hGH阳性各1例.结论原发于蝶窦的垂体腺瘤比较少见,主要根据光镜及免疫组化确诊,应注意与慢性蝶窦炎和浆细胞瘤鉴别.  相似文献   
64.
The absolute granulocyte count (AGC) in 125 blood samples from patients with total white blood cell counts of less than 1,000/microliter was estimated using three different methods, which were then compared for efficiency and accuracy. The three methods were 25 cell differential counts using Wright's-stained blood smears, granulocyte percentage estimates from WBC counting chambers, and combined narrow- and wide-angle light-scatter characteristics determined on a flow cytometer. A survey of clinical laboratories at University Hospital Cancer Centers revealed that the smear differential was the most-often-used method in those laboratories even when less than 25 cells could be counted. Consequently the data obtained from the counting chamber and flow cytometer methods were compared to the smear differential "standard" using linear regression, and outliers were identified. There was good correlation between AGC determined by smear differential and WBC counting chamber (correlation coefficient .911) and excellent correlation between the AGC determined by smear differential and the flow cytometer method (correlation coefficient .970). The flow cytometer method used in this investigation required minimal specimen preparation, and test results were available at a rate of 60 seconds/sample. The ease of sample preparation, speed, and statistical reliability of test results makes the flow cytometer an attractive alternate method of determining granulocyte counts on leukopenic patients as compared to the stained blood smear differential.  相似文献   
65.
The innervation of four functionally different muscles (subalar, remotor 1, remotor 2, pleuroalar), all served by the same nerve branch, was studied in both winged segments of the locust, Locusta migratoria. Several anatomical techniques were applied: With the cobalt backfill and silver intensification technique four cell types (motoneurone, dorsal unpaired median neurone, common inhibitory neurone, and small median neurone) were demonstrated. Serial sections enabled the morphology of the motoneurones to be described in more detail and in respect to a possible functional organization of the arborizations. A differential staining technique allowed us to stain various neurones in different colours in the same preparation. With this technique the anatomy of both the "rostral" and the "caudal" subalar motoneurones could be described in parallel, thus avoiding errors in comparison due to possible individual variations from preparation to preparation. Axon counts in the peripheral nerve branch enabled us to compile a list of the total innervation for each muscle. Results from other orthopterans are integrated and whether differences in the dendritic fields might be of functional significance is discussed.  相似文献   
66.
Summary Cyclophosphamide (CPA) is widely used against leukemic and lymphoproliferative diseases, but in vitro studies on response to this agent so far have been limited to instable derivatives with poor galenic properties. ASTA Z 7557 is a newly synthesized activated cyclophosphamide that circumvents the need for hepatic activation and has good stability. The critical cytotoxic lesions after exposure to bifunctional alkylating agents presumably are DNA interstrand crosslinks (ISC). We have, therefore, examined the formation and apparent removal of ISC after in vitro treatment with ASTA Z 7557 by use of the highly sensitive alkaline elution technique. Survival of murine L1210 cells was determined after 1 hour in vitro exposure with a D 37 value of 5.7 g/ml (from the initial shoulder part of the survival curve) and a Do value of 1.5 g/ml (from the exponential part of the curve). Previous labelling of L1210 cells by 125IUdR simplified the alkaline elution procedure but there was some cytotoxicity of the radiochemical itself with a reduction of cloning efficiency from 77% to 61 %. The maximum of ISC was observed at 6 h after initiation of treatment with much of the damage apparently removed at 24 h. The simultaneous presence of DNA single strand breaks (SSB), however, confounds the analysis of DNA damage at 24 h and early cytolysis and unaided death of human lymphocytes often preclude the analysis of macromolecular damage at this time. Human peripheral blood cells isolated from patients with leukemic or lymphoproliferative diseases showed a remarkable heterogeneity with regard to the formation of ISC at 3 h. Thus, analysis of macromolecular damage may become an additional prognostic factor for response to CPA beyond the morphologic classification of these diseases.  相似文献   
67.
《Value in health》2022,25(12):1977-1985
ObjectivesEstimates on the distribution of patients with multiple myeloma (MM) by line of therapy (LOT) are scarce and get outdated quickly as new treatments become available. The objective of this study was to estimate the number of patients with MM by LOT and the number of patients who have received at least 4 previous LOTs including proteasome inhibitors, immunomodulatory agents, and anti-CD38 monoclonal antibodies (mAbs).MethodsA compartmental model was developed to calculate the number of patients by LOT. Two pathways were considered based on stem cell transplant eligibility, and at each pathway, treatments were stratified in 2 types: anti-CD38 mAbs or other. The model population was stratified into 4 subgroups based on age and cytogenetic risk. Model inputs were informed from real-world evidence.ResultsThe model estimated that, in 2020, 126 869 patients were living with MM in the United States. Of these, 105 701 received treatment in any LOT, with 56 959, 27 252, 11 258, and 5217 in lines 1 to 4, respectively, and 5015 in line 5 or beyond. The model estimated that 3497 patients received at least 4 previous LOTs including proteasome inhibitors, immunomodulatory agents, and anti-CD38 mAbs. The model overall prevalence predictions aligned well with publicly available estimates.ConclusionsThis study proposes a novel framework to estimate MM prevalence. It can assist clinicians to understand future trends in MM epidemiology, healthcare systems to plan for future resource use allocation, and payers to quantify the budget impact of new treatments.  相似文献   
68.
目的:了解检测腹水标本阿拉伯糖甘露糖脂IgG抗体(LAM-IgG)指标诊断与鉴别诊断结核性腹水的应用价值。方法:研究对象包括恶性腹水组(恶性组)38人,结核性腹水组(结核组)32人,其他良性腹水组(对照组)32人,采集腹水为检测标本,应用斑点免疫金渗滤试验(dot-IGFA)技术检测LAM-IgG。结果:LAM-IgG的阳性结果为:恶性组5.3%(2/39),结核组65.6%(21/32),对照组0。结论:在诊断与鉴别诊断结核性腹水方面,LAM-IgG指标的特异性,敏感性均较高,具有应用价值。  相似文献   
69.
目的 :筛选和鉴定人原发性食管癌组织的相关基因 ,揭示食管癌的癌变机理。方法 :用高效、灵敏的荧光mRNA差异显示技术 ,以食管癌及相应的正常食管粘膜组织为对照 ,通过对其基因表达的比较 ,找出差异条带 ,利用ReverseNorthernDotBlot、DNA序列分析和NorthernBlot,并结合mRNA原位杂交技术对被筛片段进行鉴定。结果 :①在实验中分离、鉴定了 74条差异片段 ,其中包括正常组织表达而癌组织中不表达的差异片段 5 4个 ,癌组织中表达而正常组织不表达的差异片段 2 0个。②其中 1个片段C5 7(337bp)在GenBank数据库中没有发现同源的已知基因或片段 ,推测其可能为食管癌相关基因。③经NorthernBlot检测C5 7在癌组织中有表达信号。④原位杂交技术检测C5 7在癌组织中具有较高的阳性表达率 (74% )。结论 :食管癌组织中C5 7可能是新的食管癌相关的候选癌基因 ,它与食管癌的发生发展可能有关  相似文献   
70.
背景:创伤性脊髓损伤在临床上主要依赖于量表评估与影像学检查,但对于损伤程度的预后评估具有一定局限性,利用代谢组学技术进行生物标志物筛选,对于估计病变范围、损伤与恢复程度以及开发新疗法具有重要意义。目的:使用代谢组学技术来表征创伤性脊髓损伤患者的代谢特征,探寻潜在的生物标志物及失调的代谢途径。方法:收集20例创伤性脊髓损伤患者(观察组)和10例健康受试者(对照组)的血清和尿液样本,进行代谢物分析,然后利用多元变量统计分析进行数据处理,筛选差异代谢物。通过MetaboAnalyst软件进行代谢通路富集,应用logistic回归构建生物标志物组合模型,并分析其与美国脊髓损伤协会(ASIA)分级的关系。结果与结论:两组受试者的血清和尿液中分别检测出160种和73种具有显著差异的代谢物。通路富集分析显示,创伤性脊髓损伤后脂质代谢出现明显的紊乱,包括鞘脂类、亚油酸、α-亚麻酸和花生四烯酸代谢以及糖基磷脂酰肌醇生物合成。识别出他索沙坦和葫芦素糖苷这组生物标志物,并且二者构成的代谢物组合在血清和尿液中的水平与ASIA分级存在相关性。由此可见,代谢组学技术为进一步理解创伤性脊髓损伤病理机制、筛选治疗靶点提供帮助。识别出的代谢生物标志物组合可能为评估创伤性脊髓损伤的严重程度提供参考。  相似文献   
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