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891.
以高频喷射通气结合胸壁挤压(HFJV+CWC)为通气模式,观察其对组胺致肺损伤犬呼吸循环功能的影响,并与单纯高频喷射通气(HFJV)进行比较。结果表明:与HFJV相比,HFJV+CWC时的功能残气量(FRC)、PaCO_2和PCO_2均显著降低(P<0.01),肺泡通气量(V_A)和二氧化碳排出量(CO_2)均显著增高(P<0.01),每分呼出气量(V_E)、PaO_2、PCO_2、吸气峰压(PIP)、平均气道压(Paw)、呼气末压(EEP)、HR、平均动脉压(MAP)、肺动脉压(PAP)和肺毛细血管楔压(PCWP)均无显著变化(P>0.05)。提示:HFJV+CWC除保留单纯HFJV时气道开放、气道低压、良好的血液氧合、不影响循环功能等特点外,还具有增加呼气动力,改善肺泡通气,显著促进CO_2排除等优点。 相似文献
892.
W. de Riese E. B. Walker C. de Riese T. M. Ulbright W. N. Crabtree J. Messemer J. A. Jones A. Hinkel R. S. Foster J. P. Donohue T. Senge 《Urological research》1994,22(4):213-220
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only. 相似文献
893.
Using a questionnaire survey, we analyzed the relationship between the frequency of breast self-examination (BSE) and the
clinical stage and course of breast cancer in Japanese patients. BSE had been performed monthly by only 5.4% of the patients
(M group), occasionally by 35.4% (O group), and not at all by 59.2% (N group). There was a positive relationship between more
frequent BSE and an earlier clinical stage, the percentages of Tis/stage 0 and I for the M, O, and N groups being 83%, 44%,
and 36%, respectively (P<0.05). The mean maximum tumor diameters for the three groups were 1.7cm, 2.5cm, and 3.0cm, respectively. The tumor size in
the M and O groups was significantly smaller than that in the N group atP<0.01 andP<0.05, respectively. The percentages of patients in the M, O, and N groups who underwent breast-conserving therapy were 42%,
11%, and 19%, respectively, with patients who had performed monthly, BSE more frequently undergoing breast-conserving therapy
(P<0.05). At a median follow-up time of 34 months, 0%, 3.8%, and 7.6% of the patients from the M, O, and N groups, respectively,
had died of breast cancer, the overall survival curve of the M group being significantly better than that of the N group (P<0.01). This retrospective study suggests the positive correlation of BSE frequency with earlier detection, and a more favorable
clinical course in Japanese breast cancer patients. 相似文献
894.
Dr. Mary S. Brady MD Carol F. Garfein MBA Jeanne A. Petrek MD Murray F. Brennan MD 《Annals of surgical oncology》1994,1(1):66-72
Background: Many patients treated for breast cancer with radiotherapy will survive their disease and be at risk for treatment-related sarcoma for many years.
Methods: In order to identify patients with post-treatment sarcoma and define this disease, we examined the records of 99 patients treated for sarcoma with a history of antecedent breast carcinoma. Of these patients, 51 were felt to have a sarcoma unrelated to breast cancer treatment and 48 were felt to have a treatment-related sarcoma (secondary to lymphedema and/or radiation).
Results: Lymphangiosarcoma of the extremity was the most common histologic subtype of post-treatment sarcoma, accounting for 22 of 48 cases (46%). Twenty-six patients (54%) developed nonlymphangiosarcoma post-treatment sarcoma; all of these were radiation-associated sarcomas. The median latency interval between the diagnosis of breast cancer and the development of sarcoma was 11 years (range 4–44) and was not different between the two groups. However, patients with nonlymphangiosarcoma were significantly younger when diagnosed with breast cancer than were those with lymphangiosarcoma of the extremity (median 43 vs. 51 years, p<0.001). The survival of all 48 patients was poor: 5-year survival was 29%. Five-year survival of patients with other types of post-treatment sarcoma was just as poor as those with lymphangiosarcoma of the extremity (30% vs. 28%, p=0.98).
Conclusions: Patients who develop sarcoma after treatment for breast cancer have a poor prognosis whether it occurs as Stewart-Treves syndrome or other types of post-treatment sarcoma. Younger patients may be at higher risk than are older patients for the development of nonlymphangiosarcoma post-treatment sarcoma.Presented at the 46th Annual Cancer Symposium of the Society of Surgical Oncology, Los Angeles, March 18–21, 1993. 相似文献
895.
对食管癌高发区粮食中分离的互隔交链孢霉的毒素交链孢酚单甲醚(AME)在大鼠、小鼠体内的分布进行研究。给动物腹腔内注射氚标记的交链孢酚单甲醚(~3H-AME),然后在不同时间测各脏器的放射性。结果表明:在所测9个脏器中,2h肝脏含量最高,食管下段在大小鼠分别居第四和第三。但大小鼠分别在72、24h则以食管下段最高,说明AME及其代谢物在此清除较慢,即对其有较高的亲和力。 相似文献
896.
超声心动图诊断原发性心脏肿瘤 总被引:1,自引:1,他引:0
目的:探讨原发性心脏肿瘤超声心动图(ECG)特征。方法:利用ECG检查42例心脏肿瘤。其中粘液瘤38例,恶性肉瘤2例,均经手术病理证实。横纹肌瘤2例,经随访证实。结果:ECG对38例粘液瘤,2例横纹肌瘤全部做出正确诊断。2例恶性肿瘤提示相应部位占位病变。粘液瘤多发生在左房,有明确的瘤蒂,肿瘤回声稀疏,活动度大。恶性肿瘤回声较强、无蒂,活动度小。横纹肌瘤多发生在室壁心肌内,呈结节状,与正常心肌间有明确的界限。结论:ECG对原发心脏肿瘤的诊断具有重要意义,可初步区分良、恶性肿瘤。 相似文献
897.
H. J. C. M. Sterenborg M. Motamedi R. F. Wagner Jr M. Duvic S. Thomsen S. L. Jacques 《Lasers in medical science》1994,9(3):191-201
The feasibility of using in vivo autofluorescence for the diagnosis of skin cancer was evaluated. In vivo fluorescence measurements
were performed on healthy human volunteers, and patients with different types of benign and malignant skin tumours. Fluorescence
spectra as well as fluorescence images were acquired. The excitation-emission matrix of normal skin (n=3) showed a broad peak at the shortest excitation wavelength (365 nm) and at 440 nm fluorescence wavelength, smoothly decreasing
towards longer excitation and fluorescence wavelengths. Non-melanoma skin tumours (n=31) and control skin excited with 375 nm showed a broad fluorescence band from 400 to 700 nm, peaking around 436 nm. No significant
differences in measurements between tumours and the corresponding control sites were found. A large spatial variation in the
fluorescence intensity was observed both in the tumours and in the control sites. Standard deviations found ranged from 0.15
to 1.5 times the mean fluorescence. Fluorescence images, excited with 375 nm and taken with an image intensified CCD camera,
on eight malignant melanomas and eight benign pigmented lesions did not indicate any fluorescence intensity distribution specific
to the malignancy of the lesion. Neither the shape of the fluorescence spectra, nor the spatial distribution of the fluorescence
intensity showed any signature specific to the histopathological nature of the lesions investigated. Optical diagnostics of
skin tumours using the autofluorescence does not seem to be feasible at the present time. 相似文献
898.
J. Zieren H. U. Zieren J. M. Müller 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(3):159-167
Zusammenfassung Im Rahmen einer retrospektiven Untersuchung wurden 50 Resektionen wegen primärer Lebermalignome, die vom 1. 6. 1979 bis zum 31. 12. 1991 an der Chirurgischen Universitätsklinik Köln durchgeführt wurden, analysiert. Die Resektionsrate betrug 28 %. Die Kliniksletalität betrug insgesamt 22 % und konnte in den letzten 5 Jahren auf 4% gesenkt werden. Die Ein-, Dreiund Fünfjahresüberlebensraten betrugen unter Einschluß der Kliniksletalität 55%, 30% und 24%. Wichtigster Prognosefaktor war die chirurgische Radikalität. In einer Literaturanalyse wurden die Ergebnisse von 8725 Leberresektionen wegen primärer Lebermalignome, die zwischen 1980 bis 1992 publiziert wurden, untersucht. Die Resektionsrate betrug im Durchschnitt 32 ± 17%. Die Kliniksletalität konnte von 15 ± 5% (Resektionen vor 1970) auf 6 ± 2% (Resektionen nach 1980) gesenkt werden. Die Ein-, Drei- und Fünfjahresüberlebensraten betrugen 66 ± 17%, 39 ± 15% und 27 ± 10%. Bis auf eine geringere Kliniksletalität asiatischer Studien (4 % vs. 7%) waren die Resektionsraten und Langzeitergebnisse von asiatischen, amerikanischen und europäischen Studien durchaus vergleichbar. Die Langzeitprognose wird in erster Linie durch die erreichte chirurgische Radikalität sowie die Größe und Ausdehnung des Tumors zum Zeitpunkt der Resektion beeinflußt. Die Effektivität adjuvanter Therapien ist noch nicht ausreichend untersucht.
Liver resection for primary liver tumors. Our own results and an analysis of the literature
In a retrospective study we analysed 50 resections for primary liver tumors performed between 1 July 1979 and 31 December 1991 at the Department of Surgery of the University of Cologne. The mean resectability rate was 28 %. Hospital mortality after resection was 22% and could be reduced to 4% during the last 4 years. The overall survival rates after 1, 3 and 5 years were 55%, 30% and 24% respectively. The surgical radicality is the most important prognostic factor. In a review of the literature the results of 8,725 resections for primary liver malignancies published between 1980 and 1992 were analyzed. The mean resectability rate was 32 ± 17%. The hospital mortality after resection could be reduced from 15 ± 5% (resections before 1970) to 6 ± 2 % (resections after 1980). The overall survival rates after 1, 3 and 5 years were 66 ± 17%, 39 ± 15% and 27 ± 10%, respectively. Apart from a lower hospital mortality in Asian studies (4 % vs. 7 %) the resection rates and long-term results of Asian, American and European studies were similar. Long-term prognosis predominantly depended on the surgical radicality and on the size and extension of the tumor at the point of resection. The effectivity of an adjuvant tumor therapy is not analyzed sufficiently.相似文献
899.
Summary Prosthetic materials, such as metals, marlex mesh and methyl methacrylate have been used for stabilization of the chest wall after resection of large areas of rib cage. Such materials are contraindicated in an infected area. A new method of providing a stable chest wall using autogenous tissue is presented. 相似文献
900.
我们用卡介苗(BCG)直接作用于体外培养膀胱癌细胞株,用扫描电镜和相差显微镜观察,癌细胞形态学发生明显变化,癌细胞表面结构损伤严重,微绒毛和长突起消失,残存畸变,小球密集成片,肿瘤表面结构与胞体分离,癌细胞生长抑制曲线表明,癌细胞的生长抑制率随着时间延长和BCG浓度增大而增高。实验证明,BCG对膀胱细胞有直接损伤作用。 相似文献