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991.
992.
IJ Diel M Kaufmann SD Costa R Holle G von Minckwitz EF Solomayer S Kaul G Bastert 《Canadian Metallurgical Quarterly》1996,88(22):1652-1658
BACKGROUND: Approximately 30% of the patients with primary breast cancer who have no axillary lymph node involvement (i.e., lymph node negative) at the time of surgery will relapse within 10 years; 10%-20% of the patients with distant metastases will be lymph node negative at surgery. Axillary lymph node dissection, as a surgical procedure, is associated with frequent complications. A possible alternative to nodal dissection in terms of prognosis may be the immunocytochemical detection of tumor cells in bone marrow. PURPOSE: In a prospective study, the value of tumor cell detection (TCD) in bone marrow was compared with axillary lymph node dissection in the prognosis of primary breast cancer after surgery. METHODS: Data from 727 patients with primary, operable breast cancer were included in the analysis. All patients had surgery, including axillary lymph node dissection, from May 1985 through July 1994 at the Women's Hospital of the University of Heidelberg (Federal Republic of Germany). Bone marrow aspiration at two sites on each anterior iliac crest was performed immediately after surgery while the patients were under general anesthesia. Most patients received some type of systemic adjuvant therapy. The monoclonal antibody 2E11, directed against the polymorphic epithelial mucin TAG12, was used to detect tumor cells in bone marrow samples. The association of TCD with recognized prognostic indicators was evaluated by means of chi-squared tests. Survival without the development of distant metastases (i.e., distant disease-free survival) and overall survival were estimated by use of the Kaplan-Meier method; the logrank test was used to compare survival curves. A multivariate Cox regression analysis with stratification according to adjuvant treatment type was used to assess the independent prognostic value of TCD in bone marrow in relation to other variables. Reported P values are two-sided. RESULTS: Tumor cells were detected in the bone marrow of 203 (55%) of 367 lymph node-positive patients and in 112 (31%) of 360 lymph node-negative patients. TCD was associated with larger tumors (P < .001), lymph node involvement (P = .001), and higher tumor grade (i.e., more undifferentiated) (P = .002). After a median follow-up of 36 months, patients with tumor cells in their bone marrow experienced reduced distant disease-free survival and overall survival (both P values < .001). TCD was an independent prognostic indicator for both distant disease-free survival and overall survival that was superior to axillary lymph node status, tumor stage, and tumor grade. Among patients with tumors less than 2 cm in diameter, TCD was the most powerful predictor of outcome. CONCLUSIONS AND IMPLICATIONS: TCD in the bone marrow of patients with breast cancer is a valuable prognostic tool associated with negligible morbidity. Prospective randomized studies should be performed to determine whether TCD might replace axillary lymph node dissection in a defined subgroup of patients with small tumors. 相似文献
993.
SD Flamm 《Canadian Metallurgical Quarterly》1998,208(3):571-572
Isolated acute unilateral pleural effusion has twice been reported as the only symptom of ovarian hyperstimulation syndrome (Kingsland et al, 1989; Jewelewicz and Vande Wiele, 1975). The pathogenesis of this disorder is not fully understood and the presence of an isolated pleural effusion lends support to the role of systemic factors rather than purely the transudation of fluid from grossly enlarged ovaries in the progression of this disease. This article describes a second case of an isolated pleural effusion following in-vitro fertilization and embryo transfer. 相似文献
994.
Vps4p is an AAA-type ATPase required for efficient transport of biosynthetic and endocytic cargo from an endosome to the lysosome-like vacuole of Saccharomyces cerevisiae. Vps4p mutants that do not bind ATP or are defective in ATP hydrolysis were characterized both in vivo and in vitro. The nucleotide-free or ADP-bound form of Vps4p existed as a dimer, whereas in the ATP-locked state, Vps4p dimers assembled into a decameric complex. This suggests that ATP hydrolysis drives a cycle of association and dissociation of Vps4p dimers/decamers. Nucleotide binding also regulated the association of Vps4p with an endosomal compartment in vivo. This membrane association required the N-terminal coiled-coil motif of Vps4p, but deletion of the coiled-coil domain did not affect ATPase activity or oligomeric assembly of the protein. Membrane association of two previously uncharacterized class E Vps proteins, Vps24p and Vps32p/Snf7p, was also affected by mutations in VPS4. Upon inactivation of a temperature-conditional vps4 mutant, Vps24p and Vps32p/Snf7p rapidly accumulated in a large membrane-bound complex. Immunofluorescence indicated that both proteins function with Vps4p at a common endosomal compartment. Together, the data suggest that the Vps4 ATPase catalyzes the release (uncoating) of an endosomal membrane-associated class E protein complex(es) required for normal morphology and sorting activity of the endosome. 相似文献
995.
A 65-year-old woman with chronic myelomonocytic leukemia was shown to have trisomy 6 and multiple double minute chromosomes. The patient had no history of prior exposure to any mutagenic or carcinogenic agents. To our knowledge, this is the first report for presence of only these two aberrations. The expression of several oncoproteins and onco-related proteins was detected immunohistochemically in bone marrow cells. Among them, only the bcl-2 oncoprotein was positively stained in 100% of myeloblasts. Although the c-myc oncogene is frequently reported to be overexpressed in myeloid disorders with double minutes and associated with chemotherapy resistance and disease aggressiveness, in our case, the c-myc oncoprotein was not positively expressed. The patient received chemotherapy and complete hematological remission was successfully achieved. 相似文献
996.
OBJECTIVE: To reacquaint clinicians with a reportedly rare adverse event of agranulocytosis occurring after long-term administration of vancomycin and ticarcillin/clavulanate, with a subsequent review of other reported cases in the literature. CASE SUMMARY: A 45-year-old white woman with spina bifida developed agranulocytosis (2.7 x 10(3)/mm3 white blood cells with only 3% polymorphonuclear leukocytes and no reported eosinophils or basophils) after long-term administration of vancomycin and ticarcillin/clavulanate for decubitus ulcers and chronic osteomyelitis. Consequently, the cell counts rebounded rapidly on discontinuation of both medications and returned to normal within 1 week. DISCUSSION: The incidence of vancomycin-associated neutropenia is presumably rare, but the increased use of vancomycin may disclose a more frequent occurrence. It is suggested that the mechanism for the reaction is immunologically mediated, yet this remains unclear. Although it is difficult to determine the causative agent in this case, vancomycin was most suspect clinically. Ticarcillin/clavulanate is less likely because our patient has since been readmitted and treated with oxacillin, imipenem/cilastatin, and amoxicillin/clavulanate without affecting the white blood cell count. In that regard, it could be reasoned that an immunologic reaction to ticarcillin would have resulted in a similar outcome with other penicillins. CONCLUSIONS: This case serves as a reminder to clinicians that patients receiving long-term treatment with vancomycin should have their white blood cell count monitored at least weekly. 相似文献
997.
KA Walters KR Brain D Howes VJ James AL Kraus NM Teetsel M Toulon AC Watkinson SD Gettings 《Canadian Metallurgical Quarterly》1997,35(12):1219-1225
The human skin penetration of [14C]octyl salicylate from two representative sunscreen vehicles was determined in vitro. 3H-sucrose was incorporated into all formulations and provided a marker for membrane integrity. When applied as a finite dose in an oil-in-water emulsion vehicle containing 5% (w/w) octyl salicylate, the average total absorption of 14C over 48 hr was 0.65+/-0.16% of the applied dose (representing a total amount permeated of 1.58+/-0.36 microg/cm2). When applied as an infinite dose in the oil-in-water emulsion vehicle the average total absorption of 14C over 48 hr was 0.47+/-0.22% of the applied dose (representing a total amount permeated of 27.54+/-13.91 microg/cm2). When applied as a finite dose in a representative hydroalcoholic formulation containing 5% (w/w) octyl salicylate, the average total absorption of 14C over 48 hr was 0.59+/-0.09% of the applied dose (representing a total amount permeated of 1.58+/-0.25 microg/cm2). When applied as an infinite dose in the hydroalcoholic formulation the average total absorption of 14C over 48 hr was 0.23+/-0.05% of the applied dose (representing a total amount permeated of 11.28+/-2.55 microg/cm2). The penetration of [14C]salicylic acid [applied at a concentration of 2.7% (w/w), in the oil-in-water emulsion] was also determined. When applied as a finite dose the average total absorption of 14C over 48 hr was 1.14+/-0.23% of the applied dose (representing a total amount permeated of 1.65+/-0.39 microg/cm2). These results suggest that the in vitro human skin permeation of octyl salicylate is relatively low. The amounts of octyl salicylate and salicylic acid permeated when applied in similar vehicles were remarkably similar over 48 hr (1.58 microg/cm2 and 1.65 microg/cm2, respectively). This suggests the possibility that the 14C label appearing in the receptor fluid may, in both cases, represent salicylic acid. If this is the case, then it is possible that the amount of octyl salicylate permeating through the skin is much less than that suggested by the data obtained here. This supposition is, however, entirely speculative and has yet to be confirmed experimentally. 相似文献
998.
F Zhang WC Lineaweaver T Ustüner SD Kao HP Tonken D Campagna-Pinto HJ Buncke 《Canadian Metallurgical Quarterly》1997,99(3):803-814
The gracilis muscle model was used either as a denervated muscle in situ or as a transplanted flap in 273 rats to compare the trophic effects of muscle reinnervation and neurotization using sensory and motor nerves. The average gracilis muscle flap weighed 626 +/- 94 mg at the time of the initial procedure. Experimental muscles were examined 6 months following the procedure. In denervated, nontransplanted muscles, both motor nerve reinnervation and neurotization resulted in significantly preserved muscle mass, averaging 570 +/- 69 and 521 +/- 116 mg, respectively, compared with the denervated control average of 178 +/- 22 mg (p < 0.05). Sensory nerve reinnervation and neurotization produced much smaller trophic effects (p > 0.05). In transplanted gracilis free flaps, however, only direct reinnervation with motor or sensory nerves resulted in improved bulk preservation, with average weights of 313 +/- 83 and 327 +/- 91 mg compared with the control average of 201 +/- 76 mg (p < 0.05). Neither sensory nor motor neurotization was significantly effective in the free-flap model (p > 0.05). These data suggest that transplantation may alter the response of muscle to reinnervation. 相似文献
999.
WW Han A Incesulu MJ McKenna SD Rauch JB Nadol RJ Glynn 《Canadian Metallurgical Quarterly》1997,107(9):1185-1192
Seventy-four revision stapedectomies performed consecutively over 10 years (1986 to 1995) were reviewed retrospectively. The most common intraoperative findings were incus erosion, prosthesis displacement, and oval window closure. Incus erosion was more frequently associated with multiple revisions. The postoperative results were reported using the conventional method (postoperative air minus preoperative bone) as well as the guidelines recently published by the American Academy of Otolaryngology--Head and Neck Surgery (postoperative air minus postoperative bone), with success rates of postoperative air-bone gap closure to within 10 dB after revision surgery of 51.6% and 45.6%, respectively. Patients with persistent conductive hearing loss (large residual air-bone gaps) after primary stapedectomy had poorer postrevision hearing results. Sensorineural hearing loss (defined as a drop in bone pure-tone average of more than 10 dB) occurred in four cases (5.4%). The number of revision surgeries, variations in operative techniques using laser or drill, and the ossicle to which the prosthesis was attached did not statistically affect the postoperative air-bone gaps. These results were compared with previously published data. 相似文献
1000.