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71.
The treatment results obtained in patients with both small and non small cell lung cancer have remained stagnant for years. Therefore, in order to select patients who will have a profit from radiotherapy the indication has to take into account prognostic factors such as tumor stage, extent of resection, patient's age, lymph node status, weight loss and the patient's performance status. Non small cell lung cancer: Postoperative radiotherapy seems to benefit only in patients with hilar or mediastinal lymph node involvement, where a five-year survival rate of up to 30% of cases can be achieved. Postoperative irradiation should not be applied following curative resection and negative lymph node status (R0 N0). In inoperable cases conventional fractionated radiotherapy may definitively have a favourable effect on the patient's survival time, even when the treatment was originally intended to be merely palliative. Only those patients will live five years, who received more than 50 Gy to the hilar and mediastinal nodes and at least 60 Gy to the primary lesion. The volume to be irradiated must include the primary tumor, the ipsilateral and contralateral hilum, the mediastinum, and both supraclavicular regions. If a Pancoast tumor is present, radiotherapy alone obtains a similar result as preoperative irradiation followed by resection. Small cell lung cancer: Radiation treatment of the primary tumor region and the lymph drainage area increases the remission rate by roughly 20% compared with chemotherapy alone, considerably reduces the incidence of local recurrences and exerts a beneficial effect on the survival of the patients. Recently, this has been confirmed by prospectively randomised protocols. Prophylactic brain irradiation has been found to decrease the risk of cerebral metastases to 4-6% in patients affected by limited disease and complete tumor remission under chemotherapy, and to improve the quality of life without, however, showing the benefit on survival time. Future efforts in radiotherapy should be aimed not only at increasing dose intensities but also at developing less toxic treatment modalities to the benefit of the quality of life.  相似文献   
72.
There has been a marked shift in the causes of arterio-venous fistulae. Gunshot and stab wounds used to be the most frequent cause but iatrogenic fistulae, especially those arising as a result of reconstructive skeletal operations or following diagnostic and therapeutic procedures, are now becoming increasingly common. If morphological vascular changes have not yet occurred and cardiac volume overloading has not led to permanent damage, a recently established arterio-venous fistula can be easily corrected by resection and oversewing of the artery and vein. The special cases of arterio-venous fistulae arising as a result of catheter procedures in the groin have to be identified in terms of cause and morphology in order to facilitate early surgical correction.  相似文献   
73.
In 1995, a federal cancer registry law became effective in Germany obliging all federal states to set up epidemiological cancer registries. As a result,numerous cancer registries have been established. However, it is essential to know the degree to which all relevant cases are recorded within a registry—particularly for those registries established recently—as only a high degree of completeness can prevent variations in the efficacy of registry procedures from distorting comparative studies. In this study, the completeness of the cancer registries was evaluated indirectly. Incidences for geographical areas covered by a cancer registry were estimated using incidence/mortality ratios of another registry known to have complete data sets. Log-linear models, successfully applied in a separate study, were fitted to incidence/mortality ratios using both the age and sex-specific data of the reference registry. These estimates were then compared with the actual data collected by the newly established registry, allowing the level of completeness to be assessed. The German Epidemiological Cancer Registry Study Group has agreed to this method and the "Dachdokumentation Krebs"—as a member of this group—performs the analyses. The first results of the study are presented in this contribution.  相似文献   
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K Orth  E Sch?lzel  H G Beger 《Der Chirurg》1992,63(5):421-425
Cryotherapy was applied to 182 rectal cancer patients in the Department of General Surgery, University of Ulm, between 4/1982 and 4/1991. Recipients of this tumor freezing therapy were patients whose general condition was bad, patients with an advanced inoperable carcinoma, patients with tumor recurrence and patients refusing operation. Rectal carcinomas, mostly in an advanced stage, were usually freezed several times. Only 4 patients with general inoperability reached the survival time margin of 5 years. In 18 patients local tumor destruction was possible by application of cryotherapy. In 80% of cases disagreeable tumor symptoms like tenesma, mucous discharge and oozing hemorrhages could be reduced or completely removed. Perianal pain and intense tumor bleeding could be relieved temporarily or definitely in only 50% of patients. An artificial anus could be avoided in 80% of cases by local tumor destruction/reduction or arrest of tumor growth. The mean survival time of patients with tumor recidivation was 11 months after onset of the recurrence. Tumor progression, incontinence and iatrogenic rectal perforation made an artificial anus necessary in 14 patients.  相似文献   
77.
Exposure of cultured human glomerular mesangial cells (GMC) to normal human serum and an activator of the complement system results in rapid uptake of the terminal complement proteins C5b-9 by the cells. This 'innocent bystander' complement attack, however, does not result in cell killing, but in the stimulation of the GMC to release prostaglandin E (PGE), interleukin 1 (Il-1) and tumor necrosis factor (TNF). Endogenously synthesized Il-1 in turn activates PGE release, indicating that the C5b-9 attack initiates an autocrine feedback stimulation. Together with the fact that C5b-9 is found in many forms of glomerulonephritis, the data point to a role of the terminal complement proteins in the initiation and perpetuation of an inflammatory response.  相似文献   
78.
Clinical aspects of FK-506 or cyclosporine immunosuppression regimens were evaluated in 48 consecutive pediatric renal transplant recipients. Tapering and discontinuation of prednisone was employed only in children receiving FK-506 who experienced minor or no rejection episodes during the 1st posttransplant month. At 1 year follow-up, 17 of 22 (77%) of all children with functioning allografts were receiving no prednisone (n=13) or a mean dosage of 0.07 mg/kg per day (n=4). During the 1st month, acute cellular rejection was more common in the FK-506 group (0.58 vs. 0.21 rejections per patient,P<0.05) but allograft survival (92%) and renal function at 1 year posttransplant were identical in both groups. Compared with the cyclosporine regimen, FK-506 immunosuppression may be associated with a higher incidence of cytomegalovirus or reversible Epstein-Barr virus-induced lymphoproliferative disease. However, the FK-506 group had less hirsutism and gingival hypertrophy and required fewer antihypertensive medications independent of steroid use. Height standard deviation scores and weight-for-height index improved only in preadolescents receiving FK-506 but no prednisone (P<0.02 andP<0.05, respectively), but did not differ between children on FK-506 plus prednisone and those in the cyclosporine group. We conclude that the major advantages of FK-506 over cyclosporine immunosuppression are a reduced severity of hypertension and an improved cosmetic appearance which may improve long-term medical compliance. When used as monotherapy, FK-506 also shows promise in relieving the growth retardation associated with cyclosporine regimens that include prednisone.  相似文献   
79.
Nuclear Medicine offers screening methods for oncology such as bone and bone marrow scintigraphy. During the last two decades, special procedures have gained widespread application. This paper is centered around the “tumor-specific” radiopharmaceuticals. In patients with thyroid cancer, I-131 still plays a significant role. Ga-67 still has its indications in lymphoma, while in other diseases Tl-201 cloride is now the agent of choice. Especially in thyroid cancer, Tl-201 has proved to be a reliable tumor imaging radiopharmaceutical. More recently, Tc-99m MIBI was introduced for tumor imaging. Tc-99m HMPAO may also be used for tumor scintigraphy, especially in brain lesions. In addition, I-123 IMP has successfully been used for imaging malignant melanoma. Another promising field of tumor diagnosis is receptor imaging. In neuroblastoma and malignant pheochromocytoma, I-131/123 mIBG is the radiopharmaceutical of choice and may be considered as a receptor imaging agent also. First clinical results with In-111 octreotide show potentials as somatostatine-receptor radiopharmaceutical in insulinoma, islet cell carcinoma, medullary and lung cancer, while I-123 estradiol needs some improvement until it may be recommended as diagnostic tool in breast cancer. Since 1978, radiolabeled poly- or monoclonal tumor antibodies and their fragments have gained widespread application. Especially the Tc-99m 225.28S melanoma antibody, I-131 or Tc-99m CEA and In-111/I-131 labeled OC-125 antibodies have proven to be of clinical significance in melanoma, colorectal and ovarian cancer.  相似文献   
80.
Every person has a subjective understanding of their own illness. The personal attitude towards disease and the corresponding coping mechanisms go beyond biomedical factors to influence the course of the disease. Lipowski described eight different disease concepts which were supplemented by the theory of control conviction (external-internal control). Several hypotheses about disease concepts, coping strategies and psychopathology were globally confirmed in a study of 205 chronic patients: Ability to control and acceptance lead to a more active and problem-related coping, whereas emotional coping modi occur more often in persons who do not accept their illness or do not consider it to be controllable. Results confirm the necessity of a differentiated analysis.  相似文献   
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