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41.
42.
PURPOSE: We described the temporarily increase phenomenon in prostate-specific antigen level (PSA bounce) after transperineal interstitial permanent prostate brachytherapy (TIPPB) for localized prostate cancer. MATERIALS AND METHODS: From December 1998 to May 2003, 500 consecutive patients with localized prostate cancer were treated with TIPPB using iodine-125 or palladium-103. We examined 200 patients who have more than 2-year PSA follow-up. Median follow-up length was 1,069 days (range, 712-1,411 days). No patient received neoadjuvant or adjuvant hormone therapy. PSA determinations were performed every 3 months for the first 2 years after procedure, and every 6 months hereafter. PSA bounce was defined as an increase of 0.1 ng/ml or greater above the preceding PSA level after implant followed by a subsequent decrease below that level. The American Society for Therapeutic Radiology and Oncology (ASTRO) consensus panel criteria 1996 were used to define biochemical failure. RESULTS: PSA bounce was observed in 40% (80/200) of the cases receiving TIPPB. The median time to PSA bounce was 13 months from the day of implant. The median magnitude of the PSA bounce was 0.3 ng/ml from the pre-bounce level. Twelve cases demonstrated biochemical failure according to the ASTRO consensus guidelines of three consecutive rises in PSA. Ten of these subsequently showed a drop in PSA, consistent with biologic control of their disease. Two cases remain classified as apparent biochemical failures. CONCLUSIONS: A transient rise in the PSA following TIPPB, the so-called "bounce" is a common occurrence. The apparent PSA control of ten of twelve cases failing by the ASTRO criteria raises some concern. Further observation will be necessary to determine ways to discriminate these from true disease progression.  相似文献   
43.
Preimplantation genetic diagnosis (PGD) has recently been performed for inherited cancer predisposition determined by p53 tumour suppressor gene mutations, suggesting the usefulness of PGD for late onset disorders with genetic predisposition, including those caused by the germline mutations of other tumour suppressor genes. Here PGD was performed for two couples, one at risk for producing a child with maternally derived neurofibromatosis type I (NF1), and the other with paternally derived neurofibromatosis type II (NF2). The procedure involved a standard IVF protocol, combined with testing of oocytes or embryos prior to their transfer back to the patients. Maternal mutation Trp-->Ter (TGG-->TGA) in exon 29 of the NF1 gene was tested by sequential PCR analysis of the first and second polar bodies, and paternal L141P mutation in exon 4 of the NF2 gene by embryo biopsy at the cleavage stage. In both cases, multiplex nested PCR was applied, involving NF1 and NF2 mutation analysis simultaneously with the 3 and 2 linked markers, respectively. Of 57 oocytes tested in four PGD cycles for NF1 mutation, 26 mutation-free oocytes were detected, from which eight were preselected for transfer, two in each cycle. These produced two clinical pregnancies, one confirmed to be mutation free by chorionic villus sampling but ending in a stillbirth, and the other still ongoing. Of 18 embryos analysed in a cycle performed for NF2 mutation, eight mutation-free embryos were detected, three of which were transferred back to the patient, resulting in a singleton pregnancy and the birth of a mutation-free child. This suggests that PGD is a useful approach for avoiding the birth of children with inherited cancer predisposition, determined by NF1 and NF2 gene mutations.  相似文献   
44.
Validation studies were carried out using the commercially available PCR multiplex system genRESMPX-2. In addition to amelogenin, this system comprises the complete set of eight STR systems which are components of the German DNA database established in 1998 by the Federal Criminal Office of Germany (BKA). The minimum amount of template DNA which gave a complete DNA pattern ranged between 100 pg and 200 pg. Mixed samples could clearly be assigned from ratios between 1:5 (ACTBP2) and 1:20 (VWA, FGA). Experimental investigations with different forensic materials, environmental studies, reproducibility and precision data as well as practical casework analysis revealed that the genRESMPX-2 kit can be regarded as a sensitive, reliable and robust multiplex system even in the case of samples containing limited amounts or degraded DNA.A. Junge and T. Lederer contributed equally to the data presented  相似文献   
45.
Summary In a cross-sectional, non-randomized, prospective study in an outpatient clinic a possible relationship between the cerebrospinal fluid (CSF) concentrations of the potent vasoconstrictor peptide endothelin-1 (ET-1) and prevalence and degree of HIV-encephalopathy was studied. Forty-eight CSF samples from HIV-infected patients ET-1 was also measured in plasma. Patients were investigated clinically and staged with respect to HIV encephalopathy. Patients with arterial hypertension, diabetes or acute opportunistic infections were excluded from the study. In the remaining, 18 of the CSF samples were from patients with normal neurological findings (grade 0–0.5), whereas 30 were from patients with HIV encephalopathy (grade 1–3). The mean CSF ET-1 concentration was significantly elevated (P = 0.001) in patients with HIV encephalopathy (1.97 ± 2.33 pmol/l) as compared to those patients without encephalopathy (0.57 ± 0.67 pmol/l). Moreover, there was a significant correlation between ET-1 CSF concentrations and the degree of HIV encephalopathy (r = 0.49, P < 0.001). In addition, there was a significant correlation between ET-1 levels in the CSF and the IgG serum to CSF ratio. However, we found no correlation between HIV encephalopathy and neither CSF ratio of IgG or albumin. In conclusion, we could demonstrate a close relationship between CSF ET-1 concentrations and the degree of HIV encephalopathy. Thus, by virtue of its long-lasting and potent vasoconstrictor activity ET-1 might contribute to the pathogenesis of HIV encephalopathy. Received: Februrary 23, 1999 · Revision accepted: June 30, 1999  相似文献   
46.
47.
A girl presented with an important growth retardation, hepatomegaly, fasting hypoglycemia, lactic acidosis, increased serum cholesterol, triglycerides and uric acid, and increased liver glycogen (7.5%). There was no rise in blood glucose after IV galactose or fructose, but glucagon gave a delayed response. Type Ib glycogen storage disease was suggested by the low normal activity of glucose-6-phosphatase (G-6-Pase) which reached 1.8 units/g (normal, 2 to 10 units/g) and the normal activity of other glycogenolytic enzymes, measured in homogenates prepared in H2O (mean +/- S.E. in control subjects: 59% +/- 7; in type Ia GSD: 92% +/- 3). The activity of G-6-Pase measured as described above increased to 3.8 units/g of liver 1 year after PCS and 7.85 units/g of liver after 3 years. At that time, a simultaneous assay of the enzyme in a fresh, previously not frozen liver biopsy, homogenized in 0.25 M sucrose, revealed only about 29% of the activity of the same sample prepared in H2O (mean +/- S.E. in three controls: 95.8% +/- 8.9.  相似文献   
48.
The addition of commercial dextrins to aqueous solvents in thin layer chromatography on cellulose increases the Rf values of azodyes such as methyl orange. The increase is less than with cyclodextrins but shows that dextrins also form supramolecular complexes. This should be considered when dextrins are used as "inert" excipients in pharmacy.  相似文献   
49.
OBJECTIVE: We investigated whether frequency of avalanche accidents corresponds with the danger assessment given in avalanche hazard tables and with topographic factors of the avalanche origin. METHODS: A retrospective review of official avalanche surveillance data and of medical reports from helicopter-based emergency medical systems was conducted. RESULTS: Most victims involved in avalanche accidents are ski tourers and off-piste skiers, about 90% are male, and age ranges from 10 to more than 70 years. Sixty-seven percent of accidents occurred when moderate and considerable danger was forecast. In 94.0% of accidents avalanches were triggered by victims themselves or by nearby recreationists; 32.6% of avalanche slides occurred on extremely steep slopes at gradients exceeding 40 degrees . Overall incidence of accidents before noon was 25.0%. Professional stand-by avalanche parties significantly contributed to rescuing avalanche victims, but the chance of survival is diminished when arrival was delayed. All patients who were able to free themselves from avalanche burial survived. Of those rescued by companions, 78.0% survived compared with only 10.0% of those rescued by organized rescue teams (P<0.001). CONCLUSION: Frequency of avalanche emergencies associated with outdoor leisure activities does not correspond with the danger forecast in avalanche hazard bulletins. There is need of a modified and regionally adjusted grading that makes allowance for experience and individual behavior of recreationists going in for backcountry leisure activities.  相似文献   
50.
The aim of the present investigation was to compare the efficacy of a low-dose antacid (Maalox 70, 280 mmol/day) with that of the H2-receptor antagonist cimetidine (Tagamet, 200 mg three times daily and 400 mg/day) after 14 and 28 days in the treatment of duodenal ulcer. The prospective multicentre study included 171 patients with endoscopically confirmed duodenal ulcers. The patients were randomly assigned to the treatment groups with antacid containing Mg and Al hydroxide (M)(4 X 70 mmol/day; n = 86) or to the group receiving cimetidine (T) (1000 mg/day; n = 85). The two treatment groups were matched for age, sex, drinking and smoking habits, and drug use. Endoscopic examinations were carried out before the start of treatment and 14 days later. If the ulcer was still present at this time, the second endoscopic examination was done after a further 14 days. Endoscopically, the ulcer had healed at 14 days in 38.8% (M) and in 34.9% (T) and at 28 days in 80.0% (M) and 74.7% (T), respectively. The healing rate did not differ significantly between the two treatment groups. Complaints, measured as percentage of days per week with upper abdominal pain, were significantly reduced in both groups. No significant differences were found between the two treatment groups with regard to pain relief or side effects. Treatment had to be abandoned in one patient receiving antacid because of diarrhoea and in one patient receiving cimetidine because of the absence of any response.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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