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961.
Wei-Jei Lee Jan-Show Chu Chiun-Sheng Huang Mei-Fu Chang King-Jen Chang Kai-Mo Chen 《Breast cancer research and treatment》1996,37(3):291-298
Summary In this prospective study, the authors examined 50 patients with breast tumors (malignant, n = 32; benign, n = 18) to investigate the correlation between color Doppler flow mapping and histopathological findings and to evaluate the clinical significance of color Doppler mapping. Among the 32 patients with breast cancer, color Doppler signals were detected in 24 patients (75%). The maximum flow velocities varied from 5 to 34 cm/sec, with 16 (67%) of them above 15 cm/sec. Among the 18 patients with benign tumors, color Doppler signals could be detected in 7 (39%). The maximum flow velocity varied from 3 to 30 cm/sec but was over 15 cm/sec in only two patients (28%). Histological studies revealed that color Doppler signals detected by Doppler sonography correlated with disordered neovascularization penetrating the lesion from its periphery, consisting of thin-walled blood vessels and large arteriovenous shunts. Although large tumors tend to have high Doppler flow, there is no significant correlation between the maximum flow velocity and tumor size. There is also no significant correlation between the detection of high flow color Doppler signals and the age, receptor status, tumor size, lymph node metastases, or clinical stage of patients with breast cancer. However, there is a positive association (p < 0.05) between nodal metastases and higher tumor flow velocity in T1 ( 2 cm) breast tumors, but not in larger tumors. It is concluded that color Doppler is useful in the assessment of tumor vascularity but is of limited value in the differentiation of benign from malignant lesions. However, the presence of color Doppler signals in Tl breast cancer suggesting early dissemination of the cancer might be of important clinical significance in detecting those small, apparently early, but aggressive tumors with poor prognosis. 相似文献
962.
Osteoradionecrosis occurs in approximately 10% to 15% of patients following radiation therapy for head and neck cancer. In these patients, it is most commonly reported in sites involving the mandible, but it has also been reported in the maxilla, sphenoid, and temporal bones. The majority of these cases are related to some type of trauma such as dental extraction or intraoral biopsies. However, approximately 40% of these entities occur spontaneously and are felt to be secondary to cell kill in intermediate tissues such as bone and periosteum. Our literature review yielded no previously reported cases of osteoradionecrosis involving the anterior cranium. The following two cases present patients who experienced osteoradionecrosis of their frontal bone flaps following subcranial approaches for tumor resection. Both patients suffered from carcinomas involving the ethmoid sinuses; one tumor was a moderately well-differentiated squamous cell carcinoma, the other a mucinous adenocarcinoma. One patient's radiation therapy consisted of external beam photons; the other patient received external beam neutrons. Treatment for these patients, as well as possible causative factors regarding their osteoradionecrosis, are discussed. 相似文献
963.
Chang J Poole CA 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》1996,4(4):275-285
The chondron represents the chondrocyte and its pericellular microenvironment and plays an important role in the progression of osteoarthritis. Type VI collagen is preferentially localized in the pericellular microenvironment of adult articular cartilage and increases during osteoarthritis. In this study, we characterized the pericellular sequestration of type VI collagen in long-term chondrocyte-agarose cultures, and assessed the action of interleukin-1 on type VI collagen deposition and assembly. Immunohistochemical and biochemical analysis showed that cultured chondrocytes initiate type VI collagen sequestration immediately upon plating and continue pericellular matrix sequestration in a time dependent manner. Confocal microscopy confirmed the cell surface localization and pericellular accumulation of type VI collagen, while image analysis identified a 'cargo-net like' organization of type VI collagen around each chondrocyte. Quantitative analysis revealed a primary phase of rapid cell division and low levels of type VI collagen sequestration, followed by a secondary phase of relative growth stability and high levels of type VI collagen deposition. Interleukin-1 treated cultures showed increased sequestration and retention of type VI collagen in an expanded microenvironment surrounding the chondrocytes. The data suggests a role for type VI collagen in the differentiation of the pericellular microenvironment in vitro. The increased type VI collagen sequestration promoted by interleukin-1 was consistent with previous studies on osteoarthritic cartilage, and implies a functional role for type VI collagen in the chondron remodeling associated with cartilage degradation. 相似文献
964.
分析20例空蝶鞍综合征(ESS)的MRI表现和其中16例的内分泌改变。结果16例ESS均有内分泌功能异常。MRI表现有蝶鞍充满长T_1和长T_2的脑脊液;垂体受压至鞍底,冠状位呈“锚”状,矢状位呈“新月”状;垂体柄延长。结果表明ESS常具有内分泌功能紊乱,MRI对ESS具有特征性诊断意义。 相似文献
965.
Mechanism of activation of an N-ras oncogene of SW-1271 human lung carcinoma cells. 总被引:15,自引:8,他引:7
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Y Yuasa R A Gol A Chang I M Chiu E P Reddy S R Tronick S A Aaronson 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(12):3670-3674
An N-ras-related transforming gene was detected in the human lung carcinoma cell line SW-1271 and molecularly cloned. The lesion responsible for its acquisition of transforming activity was localized to a single nucleotide transition from A to G in codon 61 of the predicted protein. This lesion in the second exon results in the substitution of arginine for glutamine at this position. These findings, together with previous studies, indicate that the activation of ras oncogenes in human tumors is most commonly due to point mutations at one of two major "hot spots" in the ras coding sequence. 相似文献
966.
S C Chang 《American journal of psychotherapy》1978,32(1):105-116
All psychologic phenomena occur in consciousness. However, "consciousness" has two meanings: the faculty and the content of awareness. Traditional psychologies have largely concerned themselves with the content, neglecting the problem of the faculty, thus, limiting our understanding of human psyche. Study of meditation is a viable approach to the exploration of both meanings of consciousness. Meditation aims at a "cleansing" of the mind to reach, thereby, a content-free and conflict-free state--pure consciousness. 相似文献
967.
Chang CF 《Medical group management》1981,28(2):48-52
Is the healthcare market governed by the classical laws of supply and demand? Healthcare experts, in general, say no. This author, however, argues that traditional economic principles are relevant and capable of explaining the current nature of the healthcare market. 相似文献
968.
969.
Cytotoxic,mutagenic, and cell-cell communication inhibitory properties of DDT,lindane, and chlordane on Chinese hamster cellsin vitro 总被引:2,自引:0,他引:2
G. Tsushimoto C. C. Chang J. E. Trosko F. Matsumura 《Archives of environmental contamination and toxicology》1983,12(6):721-729
The cytotoxicity, mutagenicity, andin vitro inhibition of metabolic cooperation of DDT, lindane, and chlordane were studied with Chinese hamster V79 cells. The results showed differential cytotoxicity of these three pesticides (lindane < DDT < chlordane). There was no detectable mutagenic activity of any of these pesticides, using two genetic markers (6-thioguanine and diphtheria toxin resistance). DDT and lindane, however, were shown to have properties similar to 12-O-tetradecanoylphobol-13-acetate (a powerful mouse skin tumor promoter). Above what appeared to be a threshold level, there was a clear dose response of DDT and lindane in thein vitro cell-cell communication assay. Chlordane, which was the most cytotoxic pesticide tested, did not inhibit metabolic cooperation as significantly as did DDT or lindane. The role of these pesticides in carcinogenesis was speculated as being their tumor promoting properties, either at non-cytotoxic levels by mimicing TPA-like membrane alterations or at cytotoxic levels by mimicing partial hepatectomy. 相似文献
970.
The outcome of a department of pharmacy-initiated "streamlining" study designed to promote cost-conscious modifications of empirically selected antibiotic therapy is described. Two hundred forty-one evaluable adult patients started on restricted-use antibiotics at this university-affiliated community private teaching hospital were enrolled in a 9-week prospective streamlining study. Patients were alternately assigned to a Control (i.e., no pharmacist-initiated streamlining recommendations offered based on culture and susceptibility reports) or a Pharmacist Intervention group (i.e., pharmacist offers recommendations to streamline therapy). A statistically significant greater number of patients had their empiric antibiotic treatment courses modified to more appropriate antibiotic choices after receipt of culture and susceptibility reports among private prescribers in the Pharmacist Intervention group (83%) than in the Control group (38%) (p = .006). Additionally, pharmacists were overall successful in gaining prescriber acceptance for 64% of recommended changes of empiric antibiotic treatment courses before the receipt of culture and susceptibility reports (e.g., dose and/or frequency changes). There was no program effect observed with respect to improved physician response to microbiologic data that would allow streamlining empirical antibiotic choices in the Housestaff (i.e., medical or surgical residents), or infectious disease consultant prescriber groups. Projected overall annual cost savings that would be achieved as a result of continued efforts by pharmacists directed at streamlining empirical "restricted" antibiotic regimens is approximately +40,000. 相似文献