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31.
目前,人们正对乳腺磁共振成像(magnetic resonance imaging,MRI)的应用进行研究,表现在两个不同方面:一是将MRI列为乳腺癌高危妇女(例如BRCA1和BRCA2基因发生突变者)的筛查方法;二是对乳腺癌确诊或可疑患者行乳腺X线的同时辅以MRI以决定是否选用局部疗法。这两种用途的依据迥然不同。有预置性突变(predisposition mutations)的妇女乳腺癌发病年龄通常较低,此时由于乳腺组织较为致密,因而乳腺X线筛查的敏感性有所减低。 相似文献
32.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
33.
Monica J. Carson Tina V. Bilousova Shweta S. Puntambekar Benoit Melchior Jonathan M. Doose Iryna M. Ethell 《Neurotherapeutics》2007,4(4):571-579
Microglial activation and macrophage infiltration into the CNS are common features of CNS autoimmune disease and of chronic
neurodegenerative diseases. Because these cells largely express an overlapping set of common macrophage markers, it has been
difficult to separate their respective contributions to disease onset and progression. This problem is further confounded
by the many types of macrophages that have been termed microglia. Several approaches, ranging from molecular profiling of
isolated cells to the generation of irradiation chimeric rodent models, are now beginning to generate rudimentary definitions
distinguishing the various types of microglia and macrophages found within the CNS and the potential roles that these cells
may play in health and disease. 相似文献
34.
Julie N Hook Bruno Giordani David E Schteingart Kenneth Guire Jodie Giles Kelley Ryan Stephen S Gebarski Scott A Langenecker Monica N Starkman 《Journal of the International Neuropsychological Society》2007,13(1):21-29
Chronically elevated levels of cortisol have been associated with changes in cognitive functioning and brain morphology. Using Cushing's disease as a model to assess the effects of high levels of cortisol on cognitive functioning, 27 patients with Cushing's disease were examined at baseline and three successive follow-up periods up to 18 months after successful surgical treatment. At all follow-up periods, patients were administered cognitive tests as well as measures of plasma and urinary free cortisol. Structural MRIs and a depression measure were taken at baseline and one-year follow-up. Results showed that there is a specific pattern of significant cognitive and morphological improvement following successful treatment. Verbal fluency and recall showed recovery, although brief attention did not. Age of participants was a significant factor as to when recovery of function occurred; younger patients regained and sustained their improvement in cognitive functioning more quickly than older participants. Improvement in verbal recall also was associated with a decrease in cortisol levels as well as an increase in hippocampal formation volume one year after treatment. Overall, these findings suggest that at least some of the deleterious effects of prolonged hypercortisolemia on cognitive functioning are potentially reversible, up to at least 18 months post treatment. 相似文献
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38.
Monica Werngren-Elgstrm 《Occupational therapy international》1997,4(4):317-338
This study focuses on the communication strategies of occupational therapists. Many recent studies in occupational therapy emphasize the importance of having a client-oriented perspective; the needs and wishes of the patient should form the basis for treatment. Such a perspective brings to the fore the capacity of the therapist to enter into the life-world of the patient. Communication, dialogue between patient and therapist, is the basic source of such knowledge. In this paper, understanding verbal acts is seen as fundamentally problematic. The purpose is to analyse what strategies and tactics occupational therapists use to create a basis for their interpretation of patients' messages. What kinds of questions and other forms of verbal behaviour are utilized to check and verify these interpretations? A case-study of communication behaviour during five meetings between patients and therapists in the homes of the patients was undertaken. Seven types of tactics were observed and categorized as belonging to two different strategic dimensions: active-passive and abstract-concrete. Although active strategies were predominant, only one therapist consistently used a combination of ‘asking open questions’ and ‘verifying’ interpretations, the two most active tactics. Most therapists also asked the patients to concretely ‘show in action’ what they meant, but to a varying degree. A consistent use of active-concrete strategies is arguably an ideal way of seeking knowledge and understanding. Empirically, therapists differ in how closely they fit this ideal. This may be a result of training and experience, but also of degree of empathy. This study points to the importance of carefully developing communication strategies in order to fully understand the problems of the patients. Copyright © 1997 Whurr Publishers Ltd. 相似文献
39.
A prospective and controlled study of training after surgery for lumbar disc herniation (LDH). The objective was to determine
the effect of early neuromuscular customized training after LDH surgery. No consensus exists on the type and timing of physical
rehabilitation after LDH surgery. Patients aged 15–50 years, disc prolapse at L4–L5 or L5–S1. Before surgery, at 6 weeks,
4, and 12 months postoperatively, the following evaluations were performed: low back pain and leg pain estimated on a visual
analog scale, disability according to the Roland–Morris questionnaire (RMQ) and disability rating index (DRI). Clinical examination,
including the SLR test, was performed using a single blind method. Consumption of analgesics was registered. Twenty-five patients
started neuromuscular customized training 2 weeks after surgery (early training group=ETG). Thirty-one patients formed a control
group (CG) and started traditional training after 6 weeks. There was no significant difference in pain and disability between
the two training groups before surgery. Median preoperative leg pain was 63 mm in ETG and 70 mm in the CG. Preoperative median
disability according to RMQ was 14 in the ETG and 14.5 in the CG. Disability according to DRI (33/56 patients) was 5.3 in
the ETG vs. 4.6 in the CG. At 6 weeks, 4 months, and 12 months, pain was significantly reduced in both groups, to the same
extent. Disability scores were lower in the ETG at all follow-ups, and after 12 months, the difference was significant (RMQ
P=.034, DRI P=.015). The results of the present study show early neuromuscular customized training to have a superior effect on disability,
with a significant difference compared to traditional training at a follow-up 12 months after surgery. No adverse effects
of the early training were seen. A prospective, randomized study with a larger patient sample is warranted to ultimately demonstrate
that early training as described is beneficial for patients undergoing LDH surgery. 相似文献
40.
Christer Betsholtz Monica Nistér Fredrik Rorsman Carl-Henrik Heldin Bengt Westermark 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1989,10(1):27-36
The platelet-derived growth factor (PDGF) family consists of three different dimeric forms, AA, BB, and AB, of the two consitituent polypeptide chains, A and B. These interact with two different cell surface receptors that, in part, mediate different cellular functions. The various forms of PDGF, as well as the receptors, are expressed at high frequency in glioblastoma multiforme, and it has been suggested that the growth of this tumor might be affected by autocrine loops involving PDGF and its receptors. The present paper focuses on recent discoveries regarding the family of PDGF ligands and receptors, as well as reviews results concerning PDGF-dependent autocrine growth in experimental and spontaneous glioblastoma. 相似文献