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991.
Kreth FW  Muacevic A  Medele R  Bise K  Meyer T  Reulen HJ 《Acta neurochirurgica》2001,143(6):539-45; discussion 545-6
OBJECTIVE: To analyze prospectively the frequency and the risk of symptomatic and asymptomatic haemorrhage after image guided stereotactic biopsy of intra-axial brain tumours. METHODS: The study was conducted within a time frame of 24 months (April 1998-April 2000). 326 patients (150 males, 176 females; mean age 56.8 years) were included and 345 computerized tomography (CT)-guided stereotactic biopsies were performed/supervised by a specialized stereotactic neurosurgeon. A modified Riechert Stereotaxy System and a workstation for multiplanar trajectory planning were used in all patients. Serial biopsies (median, 5 samples) were done with small forceps (diameter 1 mm), smear preparations of the biopsy specimens were intra-operatively examined. Frequency, size, and location of any detectable bleeding were analyzed by post-biopsy CT-scan investigation. For risk estimation, logistic regression analysis was performed. The chi-square statistic was used for comparative analysis of the study results with available data from the literature. RESULTS: A conclusive tissue diagnosis could be achieved in 98%. Overall treatment morbidity was 3.1%. There was no mortality. Haemorrhage related morbidity was 0.9%. Age, Karnofsky score, mass effect of the tumour, tumour histology, tumour location and the number of specimens taken did not have any prognostic significance. The clinically silent bleeding rate was 9.6% and more often seen in patients with high grade gliomas (p = 0.03). Both the silent and non-silent bleeding rate were significantly lower as compared to available prospective data in the literature (p < 0.01). CONCLUSION: Using multiplanar image guided trajectory planning, small biopsy forceps and intra-operative smear preparations the risk of major haemorrhage related morbidity after stereotactic brain tumour biopsy is extremely low (<1%) in experienced hands.  相似文献   
992.
Leiomyosarcoma of the inferior vena cava is a rare mesenchymal tumor. The diagnostic approach, based on general guidelines of oncologic surgery, seems to be relatively routine; specific aspects of treatment, including vascular reconstruction, depend on tumor stage, grade, and location. In this report, the management of this disease in 5 patients is summarized and the literature is reviewed. A thorough diagnostic assessment includes sonography, computed tomography, angiography or duplex ultrasonography, perioperative pathohistologic examination, and appropriate differential diagnosis. Radical resection is associated with the best outcome and long-term survival. In this series, 4 of 5 patients underwent tumor resection. In 2 patients, the disease was classified as R0. Another patient had R1 status found at resection and underwent postoperative radiation after the tumor bed was marked intraoperatively. She has remained stable since treatment. One patient died of pulmonary metastases 32 months after primary R1 tumor resection. The 5th patient has been stable since diagnosis; resection was not possible because of severe accompanying diseases and because consent for surgical intervention could not be obtained from the patient. There is reasonable hope that leiomyosarcoma of the inferior vena cava can be treated successfully, even in advanced stages, with novel antineoplastic drugs and radiotherapeutic protocols. However, general treatment recommendations have not yet been compiled.  相似文献   
993.
Care of terminally ill children with cancer   总被引:1,自引:0,他引:1  
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994.
Structural equation models were applied to the maternal ratings of 265 MZ and 163 DZ male-male, 347 MZ and 160 DZ female-female, and 262 male-female twin pairs, aged 8-16 years, who participated in the Virginia Twin Study of Adolescent Behavioral Development (VTSABD). Substantial additive genetic influences and contrast effects were found for hyperactivity, and additive genetic and shared environmental effects or positive comparison effects (particularly for the girls) for oppositional/conduct disturbance. Bivariate model fitting showed that the covariation between hyperactivity and oppositional/conduct problems in both younger and older boys and girls is almost entirely attributable to genetic factors. However, whereas in the younger males and females the same set of genes explain all the variation in hyperactivity and conduct disturbance, in the older cohort at least some of the genetic effects are behavior- and gender-specific.  相似文献   
995.
The present study examined the effect of glycerol administration on 3-fucosyl-N-acetyl-lactosamine (CD15) epitope expression in the endolymphatic sac (ES) of the guinea pig's inner ear. Adult guinea pigs were injected intravenously with glycerol (2 g/kg body wt.). CD15 expression was studied at 80 min up to 5 h after treatment. In untreated animals single cells and cell groups in the ES expressing CD15 epitope intra- and intercellularly were identified by immunohistochemistry to be mainly in the epithelial layer of the rugosal and distal part of the sac. Glycerol administration modulated the expression of CD15 epitope. In the epithelial layer, expression decreased and was nearly depleted after 3 h. After 4 h of glycerol administration, CD15 expression reappeared and reached the comparable level of controls. The numbers of CD15-positive cells in the lumen of the ES increased steadily and arrived at their the highest levels in 2-h specimens. The localization of CD15-epitope expression and its modulation after glycerol administration within the ES implies that this molecule may play a role in re-establishing the sac's normal function. In addition, we speculate that CD15 may be associated with processes of an immune response in the inner ear.  相似文献   
996.
There is strong epidemiological and biological evidence that the development of squamous cell carcinoma of the cervix is a multistep process in which human papillomaviruses (HPVs) play a crucial but not total role and where the synergistic effect of herpes simplex virus (HSV) and human cytomegalovirus (HCMV) has been suggested. The presence of HPV, HSV and HCMV deoxyribonucleic acids (DNAs) was assessed by a polymerase chain reaction (PCR) in cervical biopsies obtained from 41 women with cervical neoplasia (21 high-grade cervical intra-epithelial neoplasia (CIN) and 20 squamous cell cancers) and 33 controls. Human papillomavirus 16 DNA was significantly more common in high-grade CIN (57%) and cancer (50%) than in normal cervix (9%). Herpes simplex virus and HCMV DNAs were present in 12% and 21% of normal cervices, 19% and 24% of high-grade CIN, and 25% and 25% of cancers, respectively. After adjustment for patients' age, coinfection associating high-risk HPVs (HPV 16 and/or HPV 18) and herpes viruses (HCMV and/or HSV) were observed in cervical neoplasia (odds ratio (OR) = 19.11; 95% confidence interval (CI): 2.14–170.36). Conversely, the OR for infection by HPV 16 and/or HPV 18 alone did not reach statistical significance (OR = 7.22; 95% CI: 0.85–61.16). Moreover infection by HCMV and/or HSV alone (OR = 0.89; 95% CI: 0.33–2.24) was not associated with cervical neoplasia. Our results support the role of HSV and HCMV as cofactors of HPV 16 and HPV 18 in cervical neoplasia.  相似文献   
997.
The four keystones of quantitative risk assessment are hazard identification, exposure assessment, dose-response assessment and risk characterization. This paper considers the different steps of risk assessment and their application to food microbiology. Traditionally, quantitative risk assessment has been viewed simply as a method to estimate risk. However, when we conduct a complete risk assessment including different factors from "farm to fork" it can serve to understand the risk process. Quantitative risk assessment can also provide valuable insights as how to best manage the risk.  相似文献   
998.
This paper examines conceptions of trust among three groups of respondents diagnosed with either breast cancer, Lyme disease or mental illness. Interviews were carried out using an open-ended interview guide to explore how patients made assessments of trust in their doctors and health care plans. The guide followed a conceptual approach that asked questions about competence, agency/fiduciary responsibility, control, disclosure and confidentiality. Respondents were given ample opportunity to raise other areas of concern. The data were organized using the NUDIST software package for the analysis of non-numerical and unstructured qualitative data. Patients viewed trust as an iterative process and commonly tested their physicians against their knowledge and expectations. Interpersonal competence, involving caring, concern and compassion, was the most common aspect of trust reported, with listening as a central focus. Most patient comments referred to learnable skills and not simply to personality characteristics. Technical competence also received high priority but was often assessed by reputation or interpersonal cues. Patients were much concerned that doctors be their agents and fight for their interests with health care plans. Disclosure and confidentiality were less common concerns; most patients anticipated that doctors would be honest with them and respect their confidences. Patients' responses also appeared to vary by their disease, their socio-demographic characteristics, their involvement with self-help groups, and how their illness conditions unfolded.  相似文献   
999.
1000.
Water and acetone extracts of the roots of Euclea natalensis A.DC. were investigated for their in vitro antibacterial properties. The Gram-positive bacteria tested appeared to be more susceptible to the extracts than the Gram-negative bacteria. The water and acetone extracts inhibited the growth of Bacillus cereus, Bacillus pumilus, Bacillus subtilis, Micrococcus kristinae and Staphylococcus aureus at concentrations ranging between 0.1 and 6.0 mg/ml. The water extract did not exert any inhibitory action on Gram-negative bacteria while the acetone extract showed inhibitory activity at a concentration of 5.0 mg/ml against all the Gram-negative bacteria investigated. The antibacterial activity of acetone extract was also investigated by a direct bioassay on TLC plates against S. aureus.  相似文献   
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