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排序方式: 共有10000条查询结果,搜索用时 218 毫秒
941.
942.
Rosendo A Rodriguez MD PhD Garry Cornel FRCS Lloyd Semelhago MD William M Splinter MD Nihal A Weerasena FRCS 《The Annals of thoracic surgery》1997,64(6):1820-1822
A pediatric cardiac case of transient obstruction of the superior vena cava by the venous cannula before cardiopulmonary bypass is presented. With venous obstruction and increase in central venous pressure, reduced cerebral blood flow velocities and absence of diastolic Doppler flow were detected. This was followed by regional cerebral venous oxygen desaturation and global electroencephalographic slowing. Reposition of the venous cannula led to the recovery of these physiologic indicators and a noncomplicated clinical outcome. 相似文献
943.
Alterations in the superoxide dismutase gene of an isoniazid-resistant strain of Mycobacterium tuberculosis. 下载免费PDF全文
Y Zhang M J Garcia R Lathigra B Allen C Moreno J D van Embden D Young 《Infection and immunity》1992,60(6):2160-2165
Genetic analysis of a set of six Mycobacterium tuberculosis strains differing in virulence for the guinea pig revealed an altered restriction enzyme fragmentation pattern associated with the superoxide dismutase (SOD) gene in a low-virulence, isoniazid-resistant strain. In addition, it was found that the SOD enzyme produced by the isoniazid-resistant strain differed in its electrophoretic mobility from the SOD of other M. tuberculosis strains. Detailed analysis of these strain-specific differences showed that the restriction fragment length polymorphism resulted from the presence of a copy of a repetitive element 552 bp upstream of the SOD gene and that the anomalous electrophoretic mobility arose from a single nucleotide change, resulting in replacement of an aspartic acid residue by histidine in the SOD enzyme of the isoniazid-resistant strain. Possible relationships between genetic changes and strain-dependent differences in virulence are discussed. 相似文献
944.
Dopamine transporter density is decreased in parkinsonian patients with a history of manganese exposure: What does it mean? 总被引:2,自引:0,他引:2
Y Kim J-M Kim J-W Kim C-I Yoo C R Lee J H Lee H K Kim S O Yang H K Chung D S Lee B Jeon 《Movement disorders》2002,17(3):568-575
Manganese (Mn) exposure can cause parkinsonism. Pathological changes occur mostly in the pallidum and striatum. Two patients with a long history of occupational Mn exposure presented with Mn-induced parkinsonism. In one patient, magnetic resonance imaging (MRI) showed findings consistent with Mn exposure, and Mn concentration was increased in the blood and urine. However, this patient's clinical features were typical of idiopathic Parkinson disease (PD). Previous pathological and positron emission tomography studies indicate that striatal dopamine transporter density is normal in Mn-induced parkinsonism, whereas it is decreased in PD. Therefore, we performed [(123)I]-(1r)-2 beta-carboxymethoxy-3beta-(4-iodophenyl)tropane ([(123)I]-beta-CIT) single-photon emission computed tomography. Severe reduction of striatal beta-CIT binding was indicated, which is consistent with PD. We propose three interpretations: (1) the patients have PD, and Mn exposure is incidental; (2) Mn induces selective degeneration of presynaptic dopaminergic nerve terminals, thereby causing parkinsonism; or (3) Mn exposure acts as a risk of PD in these patients. Our results and careful review of previous studies indicate that the axiom that Mn causes parkinsonism by pallidal lesion may be over-simplified; Mn exposure and parkinsonism may be more complex than previously thought. Further studies are required to elucidate the relationship between Mn and various forms of parkinsonism. 相似文献
945.
Comparison of p53 expression in proximal and distal gastric cancer: Histopathologic correlation and prognostic significance 总被引:2,自引:0,他引:2
Huihuan Tang MD Shuichi Hokita MD PhD Xiangming Che MD Masamichi Baba MD PhD Kuniaki Aridome MD PhD Fumio Kijima MD Gen Tanabe MD PhD Sonshin Takao MD PhD Dr. Takashi Aikou MD PhD 《Annals of surgical oncology》1997,4(6):470-474
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but
no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53
expression of proximal and distal gastric cancer concerning histopathology and prognosis.
Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical
methods.
Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher
than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference
between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology
of gastric cancer.
Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer. 相似文献
946.
Dr. Seema A. Khan MD Nick J. Gonchoroff DrPH Linda E. Miller PhD 《Annals of surgical oncology》1997,4(6):462-469
Background: Many studies have addressed the effect of the timing of surgery for breast cancer relative to menstrual cycle phase, with
conflicting results. Explanations for the possibility that survival could be altered by the appropriate timing of breast cancer
surgery in humans remain speculative.
Methods: We examined the expression of three estrogen related proteins (c-erbB-2, cathepsin D, pS2) in the breast tumors from 69 premenopausal women sampled in different phases of the menstrual cycle.
Data on S-phase fraction and hormone receptor expression were also analyzed. Immunohistochemical assays were used to measure
the proteins of interest. S-phase fraction was determined by flow cytometry. Analyses were performed based on fraction of
cells staining positive for the protein, density of stain, and a histoscore that combined both fraction of positive cells
and density.
Results: We found no differences in c-erbB-2, cathepsin D, hormone receptor, or S-phase levels in tumors sampled in the follicular versus luteal phase, or perimenstrual
versus periovulatory phase. The exception was pS2, which was expressed at greater levels during the luteal than during the
follicular phase of the cycle (p<0.01); but there was no difference in pS2 expression when the patients were classified as
periovulatory versus perimenstrual.
Conclusions: Our findings do not support a variation in c-erbB-2, cathepsin D, S-phase fraction, or receptor expression as an explanation for the differences in breast cancer prognosis
when surgery is timed by menstrual cycle phase. The finding that pS2 (an indicator of hormone sensitivity, and possibly better
prognosis) is expressed at higher levels in tumor samples during the luteal phase suggests that the biologic profile of breast
tumors may vary with the menstrual cycle and that these variations deserve further study. 相似文献
947.
Effects of race and socioeconomic status on survival of 1,332 black, hispanic, and white women with breast cancer 总被引:3,自引:0,他引:3
Dr. Luisa Franzini PhD Anna Fay Williams PhD Jack Franklin PhD S. Eva Singletary MD Richard L. Theriault DO 《Annals of surgical oncology》1997,4(2):111-118
Background: A survival disadvantage for black women with brest cancer, which persists after controlling for stage of the disease, has been reported. This study investigates the effects of race and socioeconomic status (SES) on breast cancer survival after controlling for age, stage, histology, and type of treatment.
Methods: Kaplan-Meier and Cox proportional hazards models were used to analyze the interaction between race and SES in predicting survival in a sample of 163 black, 205 Hispanic, and 964 white women with breast cancer treated at M. D. Anderson Cancer Center (1987–1991).
Results: The results of univariate and multivariate analyses indicate that race was not a significant predictor of survival after adjusting for SES and other confounding factors such as demographic and disease characteristics. SES remained a significant predictor of survival after all adjustments were made. There was no evidence of differences in type of treatment by race or SES if adjustments were made for stage.
Conclusions: These results suggest that institutional factors, such as access to treatment, do not explain survival differences by race or SES. Other factors associated with low SES, such as life-style and behavior, may affect survival. 相似文献
948.
949.
Dr. Paul Russo MD Young Kim MD Sanuj Ravindran BA William Huang BA Murray F. Brennan MD 《Annals of surgical oncology》1997,4(5):421-424
Background: Complete resection of a retroperitoneal sarcoma often requires removal of adjacent organs. In this study we evaluated the
role of nephrectomy during operation for retroperitoneal sarcoma.
Methods: Between July 1982 and July 1995, 75 of the 371 (20%) patients who underwent resection of retroperitoneal sarcoma at MSKCC
underwent concommitant nephrectomy. Data concerning the reasons for nephrectomy, degree of sarcomatous renal involvement,
and survival were retrospectively analyzed.
Results: Fifty-four patients (72%) underwent nephrectomy during the initial resection, and 21 (28%) during a resection of a recurrent
or persistent tumor. The most common reason for nephrectomy was total encasement by sarcoma (n=40; 53%), followed by dense
adherence of the tumor to the kidney (n=21; 28%), and the direct invasion of the kidney by tumor (n=2; 3%). Pathology demonstrated
an absence of kidney invasion in the majority of cases (55 of 75; 73%). Renal capsular invasion was present in 11 of 75 (15%),
renal parenchymal invasion in 7 of 75 (9%), and renal vein invasion in 2 of 75 (3%) of cases. There were no significant differences
in survival based on degree of sarcoma involvement of the kidney, tumor grade, or whether the resection was for primary or
recurrent disease. The 53 patients who underwent a complete gross resection of all tumor had a significantly improved long-term
survival compared to the 20 patients who did not (50% versus 20% DFS at 5 years, respectively; p<0.001).
Conclusions: Decisions for concomitant nephrectomy during resection of retroperitoneal sarcoma should be based on whether this maneuver
will provide a complete resection of all gross tumor, in which case the long-term disease-free survival of 50% is comparable
to the reported 5-year survival of all patients with retroperitoneal sarcoma who are completely resected.
Presented at the 49th Annual Cancer Symposium of the Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献
950.
H D Lee C O Suh W H Jung K K Oh H B Park H S Chi B R Kim J S Min 《Yonsei medical journal》1992,33(3):272-276
This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper. 相似文献