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31.
The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc.  相似文献   
32.
ObjectiveThe objective of this study was to examine both overall and disease-free survival of patients with advanced stage ovarian cancer after immediate or interval debulking surgery based on residual disease.MethodsWe performed a retrospective chart review at the Tom Baker Cancer Centre in Calgary, Alberta of patients with pathologically confirmed stage III or IV ovarian cancer, fallopian tube cancer, or primary peritoneal cancer between 2003 and 2007. We collected data on the dates of diagnosis, recurrence, and death; cancer stage and grade, patients’ age, surgery performed, and residual disease.ResultsOne hundred ninety-two patients were included in the final analysis. The optimal debulking rate with immediate surgery was 64.8%, and with interval surgery it was 85.9%. There were improved overall and disease-free survival rates for optimally debulked disease (< 1 cm) with both immediate and interval surgery (P < 0.001) compared to suboptimally debulked disease. Overall survival rates for optimally debulked disease were not significantly different in patients having immediate and interval surgery (P = 0.25). In the immediate surgery group, patients with microscopic residual disease had better disease-free survival (P = 0.015) and overall survival (P = 0.005) than patients with < 1 cm residual disease. In patients who had interval surgery, those who had microscopic residual disease had more improved disease-free survival than those with < 1 cm disease (P = 0.05), but they did not have more improved overall survival (P = 0.42). Patients with microscopic residual disease who had immediate surgery had a significantly better overall survival rate than those who had interval surgery (P = 0.034).ConclusionIn women with advanced stage ovarian cancer, the goal of surgery should be resection of disease to microscopic residual at the initial procedure. This results in improved overall survival than lesser degrees of resection. Further studies are required to determine optimal surgical management.  相似文献   
33.
Objective: The tissue-bound ovarian renin-angiotensin system (OVRAS) is critically involved in ovulation in humans and rodents. Mice with disruption and overexpression of the angiotensinogen gene (Agt) have been previously generated. We investigated the influence of varying Agt gene expression on the ovulatory capacity and early embryonic development in mice.

Design: Observational study of genetically altered mice and their response to a superovulation protocol.

Setting: Academic research institution.

Animal(s): Mice with varying copy numbers of Agt (one copy: N = 48; two copies: N = 51; three copies: N = 20; four copies: N = 24).

Intervention(s): Superovulation protocol, oocyte culture.

Main Outcome Measure(s): Number of oocytes harvested, early embryonic development of zygotes, evaluation of ovarian histology, serum estradiol measurements.

Result(s): The mean number of oocytes harvested was greatest in wild-type mice (two copies of Agt, 39.9 ± 14) with a reduction of ovulatory capacity in mice overexpressing Agt (three copies [34.8 ± 11.7] and four copies [31.2 ± 12.4], P = .026). Mice with one copy of Agt showed a slight decrease of ovulatory capacity compared to wild-type mice (35.8 ± 15.2, P = .29). Ovarian histology, serum estradiol levels, and early embryonic development were independent of the Agt genotype.

Conclusion(s): Overexpression of Agt was associated with reduced ovulatory capacity, but with none of the other parameters that were evaluated. These findings support an important role of the ovarian renin-angiotensin system in the process of follicular rupture.  相似文献   

34.
OBJECTIVE: To evaluate placental expression and serum cytokeratin-18 in women with preeclampsia. METHODS: Serum cytokeratin-18 was evaluated in 44 women with preeclampsia and 44 healthy pregnant women using an immunoradiometric assay. Placental expression of cytokeratin-18 was investigated in specimens from 23 women with preeclampsia and 20 healthy pregnant women by immunohistochemistry. RESULTS: Median serum cytokeratin-18 in women with preeclampsia and healthy pregnant women was 106.7 and 76.0 U/L, respectively (P =.02). Among women with preeclampsia, serum cytokeratin-18 was significantly associated with severity of disease (P =.001) and showed a sensitivity (standard error) and specificity (standard error) of 85% (7%) and 65% (12%), respectively. In placental specimens, the cytoplasm of the syncytiotrophoblast stained positive for cytokeratin-18 with strong and widespread staining in 83% and 45% of placental specimens of women with preeclampsia and healthy pregnant women, respectively (P =.01). CONCLUSION: Elevated serum cytokeratin-18 values are associated with disease severity in women with preeclampsia. Our data provide additional evidence that the placenta might be the source of the elevated serum cytokeratin-18 values in women with preeclampsia.  相似文献   
35.
The family histories relating to asthma and wheezy bronchitis were examined in 77 asthmatic, 78 wheezy bronchitic, and 87 control children, aged between 1 and 12 years. The percentage of children with at least one asthmatic relative was significantly greater in the asthmatic and wheezy bronchitic probands than in the controls; and asthma was more prevalent in the relatives of both groups of wheezy probands than in the relatives of controls. Similarly, the percentage of children with at least one wheezy bronchitic relative tended to be greater in asthmatic and wheezy bronchitic probands than in the controls; and wheezy bronchitis tended to be more prevalent in the relatives of both groups of wheezy probands than in the relatives of controls. However these differences did not reach significance. The strong similarities between asthmatic and wheezy bronchitic children in their family histories of asthma and wheezy bronchitis suggest that these two forms of wheezy illness share a common genetic defect.  相似文献   
36.
37.
Although laboratory animal allergy (LAA) is a significant occupational hazard among workers exposed to laboratory animals, few studies have evaluated long-term risks to workers who remain in the workplace. This short-term focus has obscured the evaluation of subsequent animal allergies (secondary LAA). We analyzed surveillance data from a 10-year LAA prevention program to estimate incidence rates of primary and secondary LAA and to evaluate the effectiveness of the prevention program in reducing the development of primary LAA. The 10-year incidence rates of primary and secondary LAA were 1.34 (95% CI, 0.78-1.90) and 11 (95% CI, 7.4-14.6) cases per 100 person-years, respectively. The annual incidence of primary LAA was reduced from 3.6% to 0 in the first 5 years and did not rise above 1.2% over the remaining years, whereas the incidence of secondary LAA was greater than 8% in most years. These findings suggest that programs effective at preventing primary LAA may need to be evaluated for their effectiveness at protecting against further risk.  相似文献   
38.
The subcooled liquid vapor pressures (P0(L),25S) and aqueous solubilities (Sw,25s) were determined and Henry's law constants (H25s) were estimated for a number of brominated flame retardants (BFRs) at 25 degrees C. The established methods of the gas chromatography-retention time and generator column techniques were used to experimentally determine P0(L),25 and Sw,25 for hexabromobenzene and a series of brominated diphenyl ether (BDE) congeners. The H25 was estimated as the ratio of P0(L)25 to the subcooled liquid aqueous solubility. Values of PL0(L),25 obtained ranged from 0.000000282 Pa (BDE-190) to 0.259 Pa (BDE-3); Sw,25 ranged from 0.00000087 g/L (BDE-153 and BDE-154) to 0.00013 g/L (BDE-15); and H25 ranged from 0.0074 Pa m3/mol (BDE-183) to 21 Pa m3/mol (BDE-15). An increase in the bromine content of polybrominated diphenyl ether congeners resulted in significant decreases Of P0(L),25, Sw25, and H25. A simple four-compartment equilibrium distribution model suggested that the majority of BFRs being released into the environment would reside in soil and sediment and have localized distributions. The model also suggested that lower brominated congeners tend to be somewhat more mobile. Degradative debromination reactions that yield these congeners would mobilize them environmentally, and ultimately affect the fate and distribution of BFRs.  相似文献   
39.
Infant injuries: accident or abuse?   总被引:6,自引:0,他引:6  
G S Gregg  E Elmer 《Pediatrics》1969,44(3):434-439
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40.
PURPOSE: To report a case of subperiosteal orbital and subgaleal hemorrhage with optic nerve compromise in a patient with a factor IX deficiency. DESIGN: Interventional case report. METHODS: A 5-year-old male presented 10 days after mild trauma with progressive left-sided scalp swelling, proptosis, and visual loss. RESULTS: The patient had marked proptosis of the left eye, 20/200 visual acuity, and an afferent pupillary defect. Magnetic resonance imaging demonstrated a large subgaleal and left subperiosteal orbital hematoma. Quantitative assays of coagulation proteins identified a factor IX deficiency (Christmas disease). CONCLUSION: Delayed-onset subgaleal and subperiosteal orbital hematoma can rarely be an initial manifestation of Christmas disease.  相似文献   
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