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排序方式: 共有445条查询结果,搜索用时 15 毫秒
1.
髁突形态与覆深度关系的研究 总被引:1,自引:0,他引:1
目的 探讨髁突形态与不同覆深度的关系。方法 选择正常者、开畸形患者、覆正常的错畸形患者和深覆畸形患者各 5 0人 ,均为 18至 2 6岁成人。应用曲面断层片研究左右两侧的髁突形态 ,分别测量并计算上部髁突高度 /升支高度比 (UCH/RH)和髁突高度 /宽度比 (TCH/CW )。将髁突形态分为四种类型 :直立型 (类A) ,前倾型 (类B) ,后倾型 (类C)和尖型 (类D)。结果 开组的上部髁突高度相对升支高度明显小于其他各组 (P <0 0 0 1)。正常组的髁突形态比较粗壮 ,高度宽度比明显小于其他各组 (P <0 0 0 1)。类A和类B属于正常髁突形态 ,占正常组的 99%。类C和类D属于异常髁突形态 ,且在开组中的比例明显高于正常覆组或深覆组。另外 ,只有开组中显示上部髁突高度两侧不对称 (P <0 0 5 )。结论 开组髁突形态与其他各组相比明显不同。 相似文献
2.
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献
3.
The purpose of our study was to compare the ultrasound findings in malignant breast masses (which underwent biopsy) with their histological appearance. In our activity of breast sonography, we observed that the same histological type of breast cancer often shows a different ultrasonic image. The main difference concerns the sonic attenuation or increase through the neoplastic mass. The histological examination took into account the amount of stroma and cells and the architectural pattern of the lesion. Comparing these features with the ultrasonic image, it has been shown that sonic transmission is related more to the architectural pattern than to the fibrous content of the neoplastic tissue. 相似文献
4.
D Santini F Bazzocchi S Pileri E Govoni M Taffurelli A Grassigli D Marrano G Martinelli 《Tumori》1985,71(4):331-338
The immunohistochemical and ultrastructural findings of 7 primary argyrophilic tumors of the breast are described. Five cases were selected because of a growth pattern reminiscent of a "carcinoid" tumor and 2 were obtained from 70 consecutive common carcinomas. All patients were females (mean age 68.8) and none had clinical evidence of hormonal secretion. On ultrastructural examination dense-core granules were seen in addition to findings more suggestive of a common carcinoma. Immunoperoxidase stainings for ACTH, calcitonin etc. were negative in all tumors. The authors believe that organoid growth pattern, argyrophilia and dense-core neurosecretory-like granules are not sufficient elements to demonstrate the endocrine nature of a breast neoplasm. 相似文献
5.
J M Pérez-Victoria B M Tincusi I A Jiménez I L Bazzocchi M P Gupta S Castanys F Gamarro A G Ravelo 《Journal of medicinal chemistry》1999,42(21):4388-4393
The effects produced by nine dihydro-beta-agarofuran sesquiterpenes isolated from Crossopetalum tonduzii (1-8) and Maytenus macrocarpa (9) (Celastraceae) on the reversion of the resistant phenotype on a multidrug-resistant Leishmania line and their binding to recombinant C-terminal nucleotide-binding domain of Leishmania P-glycoprotein-like transporter were studied. The structures of the new compounds (1-5) were elucidated by spectroscopic methods, including (1)H-(13)C heteronuclear correlation (HMQC), long-range correlation spectra with inversal detection (HMBC), ROESY experiments, and chemical correlations. The absolute configuration of one of them (1) was determined by CD studies. The structure-activity relationship is discussed. 相似文献
6.
Puglisi F Scalone S Bazzocchi M Fabris C Cacitti V Beltrami CA Di Loreto C 《Cancer letters》1998,133(2):223-229
Multiple prognostic indicators, namely histological grade and immunostaining for estrogen (ER) and progesterone receptors (PgR), MIB 1, bc1-2, and p53, were retrospectively determined on preoperative core biopsies from 75 patients with pT 1 breast carcinoma. The association of the preoperatively evaluated factors with those on the corresponding resected tumors (i.e. nodal status, histological grade, presence or absence of vascular invasion and necrosis) was assessed. In univariate analysis, histological grade on resected tumors was significantly associated with histological grade on core biopsy, p53 expression, MIB1 immunostaining. An inverse association was found between postoperative histologic grade and ER, PgR, and bc1-2. Necrosis was significantly associated with grade, p53, MIB1, and inversely with ER, PgR, and bc1-2. Nodal involvement and vascular invasion were significantly associated with MIB1. In multivariate analysis, histological grade and ER were the only independent core biopsy variables associated with postoperative histological grade and necrosis, respectively. This study showed that image-guided core biopsy is a suitable method that can be used to reveal some characteristics of the tumor biology in a preoperative stage. 相似文献
7.
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation. 相似文献
8.
BACKGROUND: The aim of this study was to review personal experience regarding bronchial carcinoids. METHODS: This study investigated retrospectively 35 patients with bronchial carcinoids treated in our institution (Unit of General and Thoracic Surgery, University of Bologna) in 20 years (from 1978 to 1997). RESULTS: The m/f rate was 0.6, the average age 42.5 years and the smokers' percentage 42.8. The patients were symptomatic in 88.6% of cases. The carcinoid was located in the right lung in 17 patients (48.5%) and central in 29 patients (82.8%). Surgical treatment included pneumonectomy (6), lobectomy (17), bilobectomy (3), sleeve lobectomy (2), sleeve bilobectomy (1), sleeve resection of main bronchus (1), bronchotomy and tumorectomy (3) and wedge parenchymal resection (2). Thirty patients (85.7%) presented a typical carcinoid and five (14.3%) atypical carcinoid. Peribronchial and/or hilar lymphonodal metastases were present at surgery in 2 cases (5.7%), both centrally located and atypical. The typical carcinoids showed a real 5 years survival rate of 95.8% (with only one death, not related to the neoplasm), while that of the atypical carcinoids was 80% (one patient died of multiple metastases). CONCLUSIONS: The conclusions is drawn that although the carcinoid tumours are a distinct group of neuroendocrine lung neoplasms with a good prognosis in the majority of the cases, lobectomy and sleeve lobectomy are still the standard resection procedure for the majority of carcinoids. For atypical carcinoids lobectomies are the minimal oncologic surgical treatment. 相似文献
9.
10.
Colonic motility and transit in health and ulcerative colitis 总被引:13,自引:0,他引:13
S N Reddy G Bazzocchi S Chan K Akashi J Villanueva-Meyer G Yanni I Mena W J Snape 《Gastroenterology》1991,101(5):1289-1297
Preprandial and postprandial colonic motility and transit (scintigraphy), with respect to the splenic flexure, were studied in 10 patients with ulcerative colitis and in 9 healthy subjects. The healthy subjects had a postprandial increase in intraluminal pressure that was significantly (P less than 0.03) greater in the descending colon than in other regions of the colon. In ulcerative colitis, the pressure was decreased in all regions compared with healthy subjects, with no significant pressure gradient among different regions. In normal subjects, transit was quiescent during fasting; eating stimulated both antegrade and retrograde transit. In ulcerative colitis, transit was variable before as well as after the meal. Both healthy subjects and patients with ulcerative colitis had more rapid emptying from the splenic flexure into the sigmoid than into the transverse colon. More frequent, low-amplitude, postprandial propagating contractions occurred in ulcerative colitis (P less than 0.05) than in healthy subjects. Propagating contractions were always antegrade and caused a rapid movement of the tracer into the sigmoid. In conclusion, ulcerative colitis is characterized by (a) decreased contractility, (b) increased low-amplitude propagating contractions, and (c) variable transit. These disturbances may accentuate the diarrhea in ulcerative colitis. 相似文献