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91.
JS van den Berg M Limburg LJ Kappelle G Pals F Arwert A Westerveld 《Canadian Metallurgical Quarterly》1998,43(4):494-498
OBJECTIVE: To determine the efficacy of lymphadenectomy after nephroureterectomy in patients with transitional cell carcinoma (TCC) of the upper urinary tract. PATIENTS AND METHODS: Between January 1986 and December 1995, 72 patients (mean age 67 years, range 45-82) underwent nephroureterectomy for primary TCC of the upper urinary tract. In 35 patients, a lymphadenectomy was also performed. The clinicopathological data were analysed retrospectively, focusing on the significance of lymphadenectomy. RESULTS: Lymph vessel invasion was found in 28 patients and its incidence was closely correlated with both tumour grade and pathological stage. Of the 35 patients who underwent lymphadenectomy, lymph node metastases were found in 13 patients, all of whom had lymph vessel invasion. There was no significant difference in the survival rate between patients with and without lymphadenectomy; however, among the 44 patients with no lymph vessel invasion, the survival rate of those with lymphadenectomy was significantly higher than in those without (P<0.05). CONCLUSION: Lymphadenectomy may provide a therapeutic advantage in patients with upper urinary tract TCC and no lymph vessel invasion. However, patients with lymph vessel invasion seem to have systemic disease; therefore, aggressive systemic adjuvant therapies rather than regional lymphadenectomy should be applied in these patients. 相似文献
92.
JS Hopkins H Chitambo N Machila AG Luckins PF Rae P van den Bossche MC Eisler 《Canadian Metallurgical Quarterly》1998,37(1-4):91-99
The indirect enzyme-linked immunosorbent assay (ELISA) for the detection of anti-trypanosomal antibodies in bovine serum was adapted for use with dried blood spots on filter paper. Absorbance (450 nm) results for samples were expressed as percent positivity, i.e. percentage of the median absorbance result of four replicates of the strong positive control serum. The antibody-ELISA was evaluated in Zambia for use in epidemiological surveys of the prevalence of tsetse-transmitted bovine trypanosomosis. Known negative samples (sera, n = 209; blood spots, n = 466) were obtained from cattle from closed herds in tsetse-free areas close to Lusaka. Known positive samples (sera, n = 367; blood spots, n = 278) were obtained from cattle in Zambia's Central, Lusaka and Eastern Provinces, diagnosed as being infected with Trypanosoma brucei, T. congolense, or T. vivax using the phase-contrast buffy-coat technique or Giemsa-stained thick and thin blood smears. For sera (at a cut-off value of 23.0% positivity) sensitivity and specificity were 86.1 and 95.2%, respectively. For bloodspots (at a cut-off value of 18.8% positivity) sensitivity and specificity were 96.8 and 95.7%, respectively. The implications of persistence of antibodies following treatment or self-cure are discussed. 相似文献
93.
BACKGROUND: Phosphorylation critically regulates the catalytic function of most members of the protein kinase superfamily. One such member, protein kinase C (PKC), contains two phosphorylation switches: a site on the activation loop that is phosphorylated by another kinase, and two autophosphorylation sites in the carboxyl terminus. For conventional PKC isozymes, the mature enzyme, which is present in the detergent-soluble fraction of cells, is quantitatively phosphorylated at the carboxy-terminal sites but only partially phosphorylated on the activation loop. RESULTS: This study identifies the recently discovered phosphoinositide-dependent kinase 1, PDK-1, as a regulator of the activation loop of conventional PKC isozymes. First, studies in vivo revealed that PDK-1 controls the amount of mature (carboxy-terminally phosphorylated) conventional PKC. More specifically, co-expression of the conventional PKC isoform PKC betaII with a catalytically inactive form of PDK-1 in COS-7 cells resulted in both the accumulation of non-phosphorylated PKC and a corresponding decrease in PKC activity. Second, studies in vitro using purified proteins established that PDK-1 specifically phosphorylates the activation loop of PKC alpha and betaII. The phosphorylation of the mature PKC enzyme did not modulate its basal activity or its maximal cofactor-dependent activity. Rather, the phosphorylation of non-phosphorylated enzyme by PDK-1 triggered carboxy-terminal phosphorylation of PKC, thus providing the first step in the generation of catalytically competent (mature) enzyme. CONCLUSIONS: We have shown that PDK-1 controls the phosphorylation of conventional PKC isozymes in vivo. Studies performed in vitro establish that PDK-1 directly phosphorylates PKC on the activation loop, thereby allowing carboxy-terminal phosphorylation of PKC. These data suggest that phosphorylation of the activation loop by PDK-1 provides the first step in the processing of conventional PKC isozymes by phosphorylation. 相似文献
94.
One hundred and seventy-one medical doctors (median age 34 years) registered as Ph.D.-students at the Medical Faculty, University of Aarhus, were given a questionnaire concerning the Ph.D-program (91% reply rate). The Ph.D.-students had typically graduated four years before enrollment and had gained basic clinical experience. Eighty-four percent had been involved in research projects prior to their formal research education. In general, the Ph.D.-students found the supervision offered by senior researchers adequate, although, more Ph.D.-students in clinical than in preclinical departments would have liked their main supervisor to be more enthusiastic and have more specific expertise. By tradition, the Medical Faculty in Aarhus offers a broad introductory course on research methodology, this was appreciated by the Ph.D.-students. However, they found that too much time was allocated for this purpose. The Ministry of Education recommends that Ph.D.-students gain experience from international collaboration, preferably from a stay abroad. However, only 24% of Ph.D.-students had stayed at an international collaborating institution. Although the overall evaluation of the medical Ph.d.-program was positive, the Ph.D.-students pointed out weaknesses and conflicts requiring adjustment. 相似文献
95.
96.
97.
Y Zhang HP Hetherington EM Stokely GF Mason DB Twieg 《Canadian Metallurgical Quarterly》1998,39(6):999-1004
OBJECTIVE: To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. METHODS: A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. RESULTS: Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. CONCLUSION: Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management. 相似文献
98.
OY Abdelmagid MM Mansour O Okwumabua S van Drunen Littel-van den Hurk 《Canadian Metallurgical Quarterly》1998,143(11):2173-2187
Glycoprotein D (gD) of bovine herpesvirus 1 (BHV-1), a homolog of herpes simplex virus gD, represents a major component of the viral envelope and is a dominant immunogen. To study the antigenic properties of the different regions of gD, we have expressed the full-length gD encoding gene and overlapping fragments spanning various regions of the gD open reading frame in a baculovirus (Autographa californica nuclear polyhedrosis virus)--insect cell (Spodoptera frugiperda, SF-9) system. Maximum levels of expression for all proteins were obtained 48 to 72 h post infection of SF-9 cells by recombinant viruses. Full-length and truncated recombinant gD proteins reacted specifically with anti-gD monospecific serum as determined by immunoprecipitation and immunoblotting, indicating that the proteins retained their antigenicity. However, based on the reactivity with a panel of gD-specific monoclonal antibodies (Mabs), the full-length recombinant gD lacked proper expression for two highly neutralizing linear epitopes identified by Mabs R54 and 9D6. The rest of the epitopes appeared to be preserved and antigenically unaltered. Immunofluorescence studies of recombinant baculovirus infected SF-9 cells using gD monospecific serum, revealed no direct correlation between cellular localization of the expressed proteins and their amino acid sequences. 相似文献
99.
The Drug Evaluation Classification Program: using ocular and other signs to detect drug intoxication
EM Kosnoski RL Yolton K Citek CE Hayes RB Evans 《Canadian Metallurgical Quarterly》1998,69(4):211-227
BACKGROUND: A systematic approach to determining drug intoxication has been developed for use by police officers. By considering specific physiological signs, trained officers can detect the effects of seven major drug types. METHODS: Officers follow a 12-step testing sequence and evaluate signs such as pupil sizes and responses, eye movements, heart rate, body temperature, mental timing, and balance. A matrix is then used to compare that subject's signs to those that would be produced by the seven types of drugs. If a pattern match is found, the officer concludes that the subject is under the influence of a drug and specifies the drug type. RESULTS: Several field and laboratory validation studies have been conducted using these procedures. In general, officers were 70% to 90% accurate in determining intoxication status and drug classification, but poly-drug use and drug rebound effects can sometimes cause problems in interpretation. CONCLUSION: Ocular and other physiological signs can be used to detect drug intoxication and classify the type of drug taken. Knowledge of the procedures used in the Drug Recognition Program can enable optometrists to serve as consultants to the police and as expert witnesses in cases involving the use of ocular signs that indicate illicit drug use. 相似文献
100.
Y Yamada EM Webber I Kirillova JJ Peschon N Fausto 《Canadian Metallurgical Quarterly》1998,28(4):959-970
We used KO mice lacking either TNF receptor 1 (TNFR-1) or receptor 2 (TNFR-2) to determine whether signaling at the start of liver regeneration after partial hepatectomy (PH) involves only one or both TNF receptors and to analyze in more detail the abnormalities caused by lack of TNFR-1 receptor, which is required for the initiation of liver regeneration. Lack of TNFR-2 had little effect on NF-kappaB and STAT3 binding, and no effect in interleukin-6 production after PH, but caused a delay in AP-1 and C/EBP binding and in the expression of c-jun and c-myc messenger RNA (mRNA). In contrast to mice lacking TNFR-1, which had deficient hepatocyte DNA synthesis and massive lipid accumulation in hepatocytes, TNFR-2 KO mice had normal liver structure and similar levels of hepatocyte DNA replication as those of wild type mice. We conclude that TNFR-1, but not TNFR-2, is necessary for liver regeneration, and that NF-kappaB and STAT3 binding are activated by signals transduced by TNFR-1. Inhibition of AP-1 and C/EBP binding and in the expression of c-jun and c-myc mRNA in the first 4 hours after PH, as well as the apparent lack of Fos in AP-1 complexes, had no effect on the timing or extent of DNA replication. 相似文献