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排序方式: 共有6215条查询结果,搜索用时 259 毫秒
41.
The increased incidence of thyroid carcinomas in familial adenomatous polyposis (FAP) patients is well recognised. These thyroid neoplasms display distinctive clinicopathological features and generally show good prognostic outcome. Recently, unusual sporadic tumours that share the morphological features of FAP-associated thyroid carcinomas have also been described. In this report, we document a case of a thyroid tumour in a previously well, 46-year-old female. Histology revealed a circumscribed neoplasm composed of tubular, papillary, cribriform and solid areas. The pseudostratified columnar tumour cells showed occasional nuclear grooves and rare nuclear inclusions. Immunohistochemistry showed positive staining with antibodies to cytokeratin AE1/AE3, oestrogen and progesterone receptor proteins. Focal immunoreactivity was also noted with antibodies to thyroglobulin, epithelial membrane antigen, 34betaE12 and cytokeratin CK7. The absence of polyps on colonoscopy and germline mutation in the adenomatous polyposis coli (APC) gene provides evidence that this tumour represents the sporadic counterpart of FAP-associated thyroid carcinoma. The patient is well with no evidence of disease 7 months following resection of the tumour. The differential diagnoses and molecular genetics of this unusual tumour are discussed. 相似文献
42.
43.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献
44.
Susan L. Swain Javed N. Agrewala Deborah M. Brown Dawn M. Jelley-Gibbs Susanne Golech Gail Huston Stephen C. Jones Cris Kamperschroer Won-Ha Lee K. Kai McKinstry Eulogia Román Tara Strutt Nan-ping Weng 《Immunological reviews》2006,211(1):8-22
Summary: We have outlined the carefully orchestrated process of CD4+ T‐cell differentiation from naïve to effector and from effector to memory cells with a focus on how these processes can be studied in vivo in responses to pathogen infection. We emphasize that the regulatory factors that determine the quality and quantity of the effector and memory cells generated include (i) the antigen dose during the initial T‐cell interaction with antigen‐presenting cells; (ii) the dose and duration of repeated interactions; and (iii) the milieu of inflammatory and growth cytokines that responding CD4+ T cells encounter. We suggest that heterogeneity in these regulatory factors leads to the generation of a spectrum of effectors with different functional attributes. Furthermore, we suggest that it is the presence of effectors at different stages along a pathway of progressive linear differentiation that leads to a related spectrum of memory cells. Our studies particularly highlight the multifaceted roles of CD4+ effector and memory T cells in protective responses to influenza infection and support the concept that efficient priming of CD4+ T cells that react to shared influenza proteins could contribute greatly to vaccine strategies for influenza. 相似文献
45.
Tales of tails: regulation of telomere length and telomerase activity during lymphocyte development, differentiation, activation, and aging 总被引:13,自引:0,他引:13
Nan-ping Weng Larry D. Palmer Bruce L Levine H. Clifford Lane Carl H. June Richard J. Hodes 《Immunological reviews》1997,160(1):43-54
Summary: Telomerase activity and the regulation of telomere length are factors which have been implicated in the control of cellular replication. These variables have been examined during human lymphocyte development, differentiation, activation, and aging. It was found that telomere length of peripheral blood CD4+ T cells decreases with age as well as with differentiation from naive to memory cells in vivo , and decreases with cell division in vitro. These results provide evidence that telomere length correlates with lymphocyte replicative history and residual replicative potential. In contrast, telomere length appears to increase during tonsil B-cell differentiation and germinal center (GC) formation in vivo. It was also found that telomerase activity is highly regulated during T-cell development and B-cell differentiation in vivo , with high levels of telomerase activity expressed in thymocytes and GC B cells, and low levels of telomerase activity in resting mature peripheral blood lymphocytes. Finally, resting lymphocytes retain the ability to upregulate telomerase activity upon activation, and this capacity does not appear to decline with age. Although the precise role of telomerase in lymphocyte function remains to be elucidated, telomerase may contribute to protection from telomere shortening in T and B lymphocytes, and may thus play a critical role in lymphocyte development, differentiation and activation. The future study of study telomerase and its regulation of telomere length may enhance our understanding of bow the replicative lifespan is regulated in lymphocytes. 相似文献
46.
北京地区精神分裂症患者家属情感表达测查报告 总被引:10,自引:2,他引:10
目的;探讨北京地区的住院精神分裂症患者家属情感表达方式及测查方法的实用性、测查工具应用的一致性。方法:经过训练的研究人员,采用费氏修订的CFI-CV访谈提纲,对171例住院精神分裂症患者家庭的284位家属进行访谈和录音,并将录音打印成文字资料。 相似文献
47.
A 2.5-month-old, 30 kg Duroc pig died 10 days after showing clinical signs of dyspnoea and diarrhoea. Acute necrotizing and fibrinous pleuropneumonia with locally extensive lesions was found. Chromobacterium violaceum was isolated from pneumonic lung tissues and intratracheal inoculation of a pure culture into two SPF pigs reproduced lesions similar to those found in the natural infection. 相似文献
48.
Ding Y He L Zhang Q Huang Z Che X Hou J Wang H Shen H Qiu L Li Z Geng J Cai J Han H Li X Kang W Weng D Liang P Jiang S 《The Journal of pathology》2004,203(2):622-630
We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS-associated coronavirus (SARS-CoV). In the present study, we used a murine monoclonal antibody specific for SARS-CoV nucleoprotein, and probes specific for a SARS-CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS-CoV systematically in tissues from patients who died of SARS. SARS-CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS-CoV may also be targets of SARS-CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS-CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS-CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS-CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS. 相似文献
49.
Risk estimates promulgated by various radiation protection authorities in recent years have become increasingly more complex. Early "integral" estimates in the form of health effects per 0.01 person-Gy (per person-rad) or per 10(4) person-Gy (per 10(6) person-rad) have tended to be replaced by "differential" estimates which are age- and sex-dependent and specify both minimum induction (latency) and duration of risk expression (plateau) periods. These latter types of risk estimate must be used in conjunction with a life table in order to reduce them to integral form. In this paper, the life table has been used to effect a comparison of the organ and tissue risk estimates derived in several recent reports. In addition, a brief review of life-table methodology is presented and some features of the models used in deriving differential coefficients are discussed. While the great number of permutations possible with dose-response models, detailed risk estimates and proposed projection models precludes any unique result, the reduced integral coefficients are required to conform to the linear, absolute-risk model recommended for use with the integral risk estimates reviewed. 相似文献
50.
Qi Chen Jiaming Feng Zhidan Liu Dongyang An Yadan Li Shaohu Zhou Zhiwei Weng 《Andrologia》2021,53(10):e14206
In the past two decades, thousands of documents in the field of prostatitis have been published. This bibliometric analysis aimed to assess the characteristics, hotspots and frontiers trend of global scientific output on prostatitis. With the trend of moderate growth, altogether 2,423 papers were reviewed. The leading role of the United States in global prostatitis research was obvious, while China had developed rapidly in recent years. Queen's University and JOURNAL OF UROLOGY were the most prolific affiliation and journal respectively. Nickel, J. C made the greatest contribution to the field of prostatitis. Five hotspots have been confirmed: (a) male infertility associated with prostatitis and the molecular mechanisms; (b) diagnosis and treatment of prostatitis; (c) inflammation, pain and bladder irritation symptoms; (d) relationship between chronic prostatitis/chronic pelvic pain syndrome, benign prostatic hyperplasia and prostate cancer; (e) epidemiology, complications of prostatitis and improvement of acupuncture. This bibliometric analysis reveals that the international cooperation was becoming more and more close. Hotspot analysis shows that the molecular mechanism of prostatitis will be a hotspot in the future, mainly focussing on inflammatory immunity and oxidative stress. 相似文献