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21.
The aim of this prospective randomized study was to determine whether additional doxorubicin chemotherapy improves outcome in patients with hepatocellular carcinoma (HCCA) treated by liver transplantation. Stratification parameters were tumor stage (UICC I-IVa), gender, age 50 years, α-fetoprotein 20 ng/mL, cirrhosis and HbsAg status. For pre-operative chemotherapy doxorubicin (15 mg/m2) was given biweekly, intra-operative chemotherapy was a single dose administered before surgical manipulation. Post-operative chemotherapy from day 10 was as given preoperatively for a total dosage of 300 mg/m2. Outcome parameters were overall survival (OS) and disease-free survival. Of the 75 consecutive patients who received liver transplantation for treatment of HCCA, 62 patients were enrolled. Thirty-four patients were randomized in the chemotherapy group; 28 patients were in the control group and transplanted only. OS rates at 5 years were 38% in the chemotherapy group and 40% in the control group, disease-free survival rates at 5 years 43% and 53%, respectively. Tumor stage and vascular invasion were identified as independent risk factors for recurrence of disease. Doxorubicin chemotherapy did not improve organ survival and disease-free survival in patients undergoing liver transplantation for HCCA.  相似文献   
22.
In a prospective study of the effect of postoperative radiation therapy for the prevention of reproliferation of membranes and recurrent proliferative vitreoretinopathy (PVR) two similar groups of patients with retinal detachment and PVR grade D1 to D3 in one eye were compared. Half the eyes (30) received a total dose of 3000 cGy after surgery; the other half remained untreated. After a followup of 6 months and 14 months or more (maximum 36 months) the anatomical and functional results of each group were compared. After 6 months in the unirradiated group 57% (17/30) remained attached and 43% (13/30) had detached again. In the irradiated group 63% (19/30) were attached and 37% (11/30) had detached. However, there was no statistically significant difference between the two groups (P=0.479, Fisher's Exact Test). After 14 months the number of cured and uncured eyes remained the same in the unirradiated group, while in four of the eyes in the irradiated group a later onset of reproliferation and detachment occurred (after 7, 8, 12 and 14 months, respectively). A final cure rate of 57% (17/30) was achieved in the unirradiated group and a 50% (15/30) cure rate in the irradiated group. Thus the failure rate was 43% (13/30) in the unirradiated group and 50% (15/30) in the irradiated group (P=0.473, Fisher's Exact Test). No side effects from the radiation were observed in any case and no radiation retinopathy occurred during an observation period of up to 3 years. The visual acuity of the cured treated and cured untreated eyes was similar in the two groups. From these results we conclude that immediate radiation treatment does not improve the long-term results and does not reduce the number of reoperations. In a considerable number of treated eyes the onset of reproliferation was delayed from 7 to 14 months, whereas in the untreated group reproliferation was always observed during the first 6 months. A combination of various antiproliferative and antiinflammatory therapies are needed to suppress recurrent PVR after succesful vitreoretinal surgery and to minimize the side effects of these treatments.Presented in part at the XVIIth Meeting of the Club Jules Gonin, 1–6 September 1990, Lausanne  相似文献   
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A partial human cDNA clone for the iron-protein (IP) subunit of succinate dehydrogenase (EC 1.3.99.1) was used in Southern analyses of restriction enzyme digests of genomic human and hamster DNA as well as hamster-human hybrids containing a limited number of human chromosomes. The gene for this protein was mapped to human chromosome 1. Digestion of genomic DNA with several restriction enzymes yielded two fragments detectable on a Southern blot, in contrast to the expectations based on the sequence of the cDNA clone. A preliminary analysis of a genomic clone with most of theIP gene has indicated the presence of several introns containing restriction sites detected by the Southern analysis. This genomic clone was also used for subregional mapping by fluorescence in situ hybridization (FISH) to human metaphase chromosomes. A single locus in the region 1p35-36.1 was identified.  相似文献   
25.
Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants.  相似文献   
26.
The study examined predictors of children's prosocial responses to adult negative emotions. An adult displayed anger, sadness and pain during play sessions with 39 preschoolers (mean age = 43 months). Older children responded more prosocially to all three emotions, whereas children with greater emotion knowledge responded more prosocially to the adult's sadness. Children who behaved prosocially in response to peers' negative emotions also were prosocial after the adult's negative emotions, even with effects of age and emotion knowledge held constant. Assertive children responded more prosocially to the adult's anger, even with effects of other variables held constant. Both theoretical and practical implications are discussed.  相似文献   
27.
This case report documents the first patient from main land China with an HTLV-1-associated myelopathy. The available epidemiological data suggest a low rate of HTLV 1 infection in China, although the surveys are comparatively small. Possible transmission routes and the risk of encountering the disease outside endemic areas are discussed.  相似文献   
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Due to decreased functional capacity as well as high environmental demands there is a risk of diminishing activity outside home in very old age (age 80+). In order to explore differences according to functional limitations (FL) among very old people with respect to frequency of activity, perceived health, overall perception of neighbourhood environment, and perceived problems in the pedestrian environment, data derived from a postal questionnaire survey to very old people living in an urban area in Sweden were used. This explorative study is based on the sub-sample of people aged 80+ who reported outdoor activities (n = 97). Four groups of respondents with different types of FL were identified: with no FL (n = 23), with only movement-related FL (n = 26), with only perception/cognition-related FL (n = 16), and with both movement- and perception/ cognition-related FL (n = 32). The majority of the respondents reported rather high frequency of activity outside home. When examining differences between the four groups, the analysis indicated how the complexity of FL and perceived problems in the pedestrian environment impacted on their activity performance. Persons with both movement- and perception/cognition-related FL were less satisfied with their frequency of activity, experienced their health more negatively and experienced more problems in the pedestrian environment than in the other groups. The findings from this study indicate the importance of considering combinations of FL in creating supportive environments for activity and health.  相似文献   
30.
Background: Inhibition of intestinal peristalsis is a major side effect of drugs used for anesthesia or for analgesia and sedation of patients in the intensive care unit. This in vitro study examined the effect of clonidine and dexmedetomidine on intestinal peristalsis and analyzed some of their mechanisms of action.

Methods: In isolated segments of the guinea pig small intestine, peristalsis was triggered by a perfusion-induced rise of the intraluminal pressure. The peristaltic pressure threshold to elicit a peristaltic wave was used to quantify drug effects on peristalsis. Vehicle (Tyrode's solution), clonidine (10 nm-100 [mu]m), or dexmedetomidine (0.1-100 nm) were added extraserosally to the organ bath. In other series of experiments, clonidine or dexmedetomidine was administered after pretreatment with yohimbine, prazosin, apamin, naloxone, or vehicle. Clonidine was also tested after blockade of NO synthase with l-NAME and in the presence of the inactive enantiomer d-NAME.

Results: Clonidine and dexmedetomidine concentration-dependently increased peristaltic pressure threshold and inhibited peristalsis (clonidine: EC50 = 19.6 [mu]m; dexmedetomidine: EC50 = 12.0 nm). The inhibition caused by clonidine could be prevented by pretreatment with yohimbine, naloxone, and apamin, but not by prazosin, l-NAME, or d-NAME. Inhibition caused by dexmedetomidine was prevented by yohimbine only.  相似文献   

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