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71.
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The present study deals with the induction of teratomas and teratocarcinomas in two strains of mice (C3H/Bln and 129/terSv). 6 to 7 days old egg cylinders were transplanted beneath the kidney capsule of adult syngeneic male and female recipients. Out of 115 grafted embryos 32 gave rise to teratoid tumors. Both the overall tumor incidence (teratomas and teratocarcinomas) and the overall percentage of teratocarcinomas were approximately the same in the strains used. In strain C3H/Bln the gender of the recipient seemed to influence the outgrowth of malignant tumors. Two transplantable C3H-teratocarcinomas could be established (DTC-4, DTC-8). Up to date both have retained their pluripotent differentiation pattern which makes them useful for intended further investigations.  相似文献   
74.
The morbidity in the long-term course following heart transplantation in childhood is mainly determined by the morbidity of the transplanted graft, by side effects caused by immunosuppression and by psychosocial morbidity due to the special situation of life and growing up with a transplanted heart. Transplant vasculopathy as a specific disease of the transplanted organ itself, is a common complication following heart transplantation and is an important factor of morbidity and mortality, considerably limiting the long-term prognosis. Progressive disturbance of renal function and cumulative incidence of malignant tumors is a further factor limiting prognosis caused by the side effects of immunosuppression.  相似文献   
75.
Paracrine renal endothelin system in rats with liver cirrhosis.   总被引:3,自引:0,他引:3       下载免费PDF全文
1. Liver cirrhosis was induced in rats by CCl4 administration. We analysed the expression of endothelin receptor subtypes in the renal cortex and medulla using Scatchard analysis and receptor autoradiography, and measured plasma as well as renal-tissue endothelin-1 concentrations using a specific radioimmunoassay. Furthermore, we analysed the effects of the non-selective (A/B) endothelin receptor antagonist, bosentan (6 and 100 mg kg-1 day-1) on mean arterial blood pressure, water and sodium excretion and glomerular filtration rate. 2. Our study revealed an overexpression of the endothelin B receptor (ETB) in the renal medulla of rats with liver cirrhosis (Cir: 2775 +/- 299 fmol mg-1; Con: 1695 +/- 255 fmol mg-1; n = 8; means +/- s.d., P < 0.01), whereas the density of ETB in the cortex and the endothelin A receptor (ETA) in the cortex and medulla were similar in both cirrhotic and control rats. Receptor autoradiography showed that the upregulation of medullary ETB in cirrhotic rats was due to an upregulation of ETB in the inner medullary collecting duct cells. 3. The tissue endothelin-1 concentrations were increased in the renal medulla of cirrhotic rats (Cir: 271 +/- 68 pg g-1wet wt.; Con: 153 +/- 36 pg g-1 wet wt., n = 8; means +/- s.d., P < 0.01). 4. The glomerular filtration rate was slightly decreased in cirrhotic rats but not altered after bosentan treatment in either cirrhotic or control rats. Bosentan decreased sodium excretion to a similar extent in both cirrhotic and control rats, whereas water excretion was significantly reduced by both dosages of bosentan in cirrhotic rats only (Cir + vehicle: 12.5 +/- 0.62 m day-1, Cir + 6 mg kg-1 day-1 bosentan: 8.6 +/- 1.0 ml day-1; Cir + 100 mg kg-1 day-1 bosentan: 7.4 +/- 0.6 ml day-1; n = 10; means +/- s.e.mean). 5. We therefore suggest that the upregulation of the medullary ETB in cirrhotic rats is involved in the regulation of water excretion in rats with CCl4-induced liver cirrhosis.  相似文献   
76.
From January, 1975 through June, 1986, 426 patients with mammary carcinomas were submitted to primary, breast-preserving therapy at the Gynecological Hospital of the University of Heidelberg. 212 women with a minimum observation time of twelve months fulfilled the criteria of a "typical" treatment: tumor size up to 3 cm, segment/quadrant resection and axillary lymphonodectomy with at least eight lymph nodes removed, radiotherapy of the residual breast with greater than or equal to 45 Gy, in case of histological lymph node manifestation adjuvant hormonal and/or chemotherapy. The average observation time was 38 months, the medium age 48 years. Patients with histological lymph node manifestations were compared with a matched control group of women treated treated by modified radical therapy. According to the error estimation of Kaplan and Meier (1958), no differences were found for local recurrence rate, disease-free survival, and overall survival. Patients treated by organ-preserving therapy with adjuvant chemotherapy were opposed to a matched control group of women treated only by surgical/radiological, organ-preserving therapy. In patients with chemotherapy, the incidence of cutaneous erythema (29% versus 24%), telangiectasia (34% versus 24%), hyperpigmentation (41% versus 34%) showed an upward tendency, but was not significantly increased. There was no difference in the incidence of clinically palpable fibroses (37% versus 42%) and fibroses shown by mammography (54% versus 51%). The frequency of pneumonitis/fibrosis of the retromammary lung area (22% versus 10%) after chemotherapy was two times higher than in the matched control group not treated by chemotherapy.  相似文献   
77.
78.
Bauer R  Remiger P 《Planta medica》1989,55(4):367-371
HPLC and TLC methods are presented for the analysis of the alkamides in ECHINACEA PURPUREA, E. ANGUSTIFOLIA, and E. PALLIDA. The roots of E. PURPUREA and E. ANGUSTIFOLIA contain different structural types of alkamides, while the roots of E. PALLIDA were almost void of amides. In contrast, the aerial parts of the three ECHINACEA species yielded very similar alkamide patterns. The methods are suitable for the analytical characterization and standardization of the three species.  相似文献   
79.
Sex-based differences in CD4 T-cell (CD4) counts are well recognized, but the basis for these differences has not been identified. Conceivably, homeostatic factors may play a role in this process by regulating T-cell maintenance and repletion. Interleukin (IL)-7 is essential for normal T-cell production and homeostasis. We hypothesized that differences in IL-7 might contribute to sex-based differences in CD4 counts. Circulating IL-7 levels were analyzed in 299 HIV-1-infected women and men. Regression analysis estimated that IL-7 levels were 40% higher in women than in men (P = 0.0032) after controlling for CD4 count, age, and race. Given the important role of IL-7 in T-cell development and homeostasis, these findings suggest that higher IL-7 levels may contribute to higher CD4 counts in women.  相似文献   
80.
The brain serotonin-2A receptor (5-HT2AR) has been implicated in both the pathology of schizophrenia and the therapeutic action of atypical antipsychotics. However, little is known about the 5-HT2AR status before the onset of schizophrenia and before the exposure to antipsychotics. We used [18F] altanserin and positron emission tomography (PET) in a pilot study of 6 individuals suspected to be at elevated risk for schizophrenia and seven age-matched controls to test the hypothesis that regional 5-HT2AR binding is altered in the prodromal stages of schizophrenia. Distribution volume ratios (DVRs) as a proxy for 5-HT2AR availability were significantly reduced in prefrontal cortex regions of at-risk subjects, implicating early abnormalities of serotonergic neurotransmission that antecede the onset of schizophrenia.  相似文献   
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