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81.
82.
Minimally invasive surgery is gaining popularity around the world because it achieves the same or even superior results when compared to standard surgery but with less morbidity. Minimally invasive breast surgery is a broad concept encompassing new developments in the field of breast surgery that work on this minimally invasive principle. In this regard, breast-conserving surgery and sentinel lymph node biopsy are good illustrations of this concept. There are three major areas of progress in the minimally invasive management of breast disease. First, percutaneous excisional devices are now available that can replace the surgical excision of breast mass lesions. Second, various ablative treatments are capable of destroying breast cancers in situ instead of surgical excision. Third, mammary ductoscopy provides a new approach to the investigation of mammary duct pathology. Clinical experience and potential applications of these new technologies are reviewed.  相似文献   
83.
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.   相似文献   
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85.
目的 观察在转化生长因子-β1(transforming growth factor betal,TGF-β1)作用下,损伤的前交叉韧带(anterior cruciate ligament,ACL)和内侧副韧带(medial collateral ligament,MCL)中骨形态发生蛋白-1(bone morphogenetic protein-1,BMP-1)基因的表达,找出TGF-31、BMP-1之间的关系,揭示机械损伤后ACL和MCL细胞中BMP-1的表达差异.方法 采用反转录PCR(RT-PCR)和实时荧光定量PCR方法检测1、5、50 ng/ml TGF-β1处理后2h受损的ACL和MCL细胞中BMP-1的表达以及5 ng/ml TGF-β1作用2、6、12、24h受损的ACL和MCL细胞中BMP-1的表达;Western blot检测5 ng/mlTGF-β1处理48 h后受损的ACL和MCL细胞中BMP-1的表达.结果 受损的ACL和MCL细胞中BMP-1的基因表达比正常状态下偏高,并随着TGF-β1浓度的增大而增高,在MCL中的增高程度比在ACL中高出近1倍(P<0.05);与正常组相比,在5 ng/ml TGF-β1处理24h后,ACL细胞中BMP-1的表达在24h达到最高比例(约为6.1倍),而在MCL中12h达到最高比例(约为9.84倍,P<0.05).5 ng/ml TGF-β1处理48 h后BMP-1蛋白也明显上调,与无TGF-β1处理的对照组相比,ACL细胞中BMP-1上调2.32倍,MCL细胞中BMP-1上调3.84倍(P<0.05).结论 TGF-β1刺激BMP-1的变化可能直接影响到细胞外基质中活性赖氨酰氧化酶的表达,对损伤ACL和MCL的修复有极其重要的参考价值和临床意义.  相似文献   
86.
Resting neutrophils may be "primed" to augmented effector function, eg, superoxide (O2-) production in the respiratory burst, upon a second stimulation with a variety of soluble agonists including formylated methionyl-leucyl-phenylalanine (FMLP) and phorbol myristate acetate (PMA). At priming concentrations of FMLP (5 x 10(-9) mol/L) that did not initiate O2- generation, two metabolic activities were noted: (1) approximately a threefold increase in the baseline intracellular calcium (Ca++i) level, that was not dependent on extracellular Ca++, and (2) a rapid rise in intracellular pH that was blocked by 5-(N,N- dimethyl) amiloride (DA), that had no effect on the Ca++i response to priming. Furthermore, there were no significant increases in inositol metabolites in cells primed and stimulated with FMLP compared with cells receiving the stimulating dose of FMLP alone and pretreatment with pertussis toxin (PT) (before the addition of the priming -5 x 10(- 9) mol/L dose of FMLP), whereas abolishing the response to FMLP during the second stage of stimulation, had (1) no effect on FMLP-primed cells subsequently stimulated with PMA, and (2) only partially ablated the rise in Ca++i initiated with FMLP. That FMLP priming involved distinctive processes to those of the well characterized FMLP-coupled Ca++-dependent activation cascade was shown by the full priming effect attained in a Ca++-free buffer, which did not sustain an O2- response to a second-stage FMLP stimulation, but sustained a primed response to PMA. These data demonstrate that FMLP primes human neutrophils by a Ca++-independent and PT-insensitive pathway, offering a functional model for studying heterogeneous FMLP receptor-coupled reactions.  相似文献   
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88.
Two cases of homozygous α-thalassaemia who received active treatment in accordance with parental wishes are reported. One infant survived and the other, although successfully weaned off mechanical respiratory support, unexpectedly developed portal vein thrombosis and died. Homozygous a-thalassaemia, a condition previously considered to be universally fatal, and an indication for therapeutic abortion, is now potentially curable with advances in diagnostic technology and treatment. However, active management of these cases raises serious ethical questions and has major financial implications on the health-care system. Invasive prenatal and intensive postnatal interventions should remain experimental and cannot be recommended as routine clinical practice until the questions of long-term neurodevelopmental outcome, and the morbidity and mortality associated with bone-marrow transplantation have been fully addressed. As a result of advances in information technology, more and more parents of affected foetuses are likely to request active treatment.  相似文献   
89.
Paget disease of the nipple: radiologic-pathologic correlation   总被引:1,自引:0,他引:1  
  相似文献   
90.
Haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) are conditions in which thrombocytopenia and microangiopathic haemolytic anaemia are associated with organ damage due to thrombotic microangiopathy (TMA). The prognosis for adults with HUS is variable, with some patients presenting with an acute illness from which a full recovery is made, whilst others develop irreversible renal failure. Evidence of retinal ischaemia was noted on presentation in a normotensive patient with irreversible renal failure due to HUS. This study examined prospectively the optic fundi of all patients who subsequently presented to a single adult renal unit (catchment population approximately 700,000) with HUS. Eleven patients presented with HUS over 12 years (1985-1997). Six patients with irreversible renal failure had retinal abnormalities either at the time or within a few days of initial presentation. The other five patients whose renal function recovered did not develop retinal changes during the course of their illness. Retinal ischaemia associated with TMA is a poor prognostic sign in adults with HUS.   相似文献   
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