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排序方式: 共有947条查询结果,搜索用时 15 毫秒
161.
FS Nielsen P Rossing MA Gall P Sk?tt UM Smidt HH Parving 《Canadian Metallurgical Quarterly》1997,46(7):1182-1188
The aim of our study was to evaluate whether inhibition of ACE (lisinopril 10-20 mg/day) can reduce the rate of decline in kidney function more than reducing blood pressure with conventional antihypertensive treatment (atenolol 50-100 mg/day), usually in combination with a diuretic. We performed a prospective, randomized, parallel study for 42 months, double blind for the first 12 months and single blind thereafter. Forty-three (21 lisinopril and 22 atenolol) hypertensive NIDDM patients with diabetic nephropathy were enrolled. Data from 36 patients (17 lisinopril and 19 atenolol, 60 +/- 7 years of age, 27 men) who completed at least 12 months of the study period are presented. At baseline, the two groups were comparable: glomerular filtration rate (51Cr-EDTA plasma clearance) was 75 +/- 6 and 74 +/- 8 ml x min(-1) x 1.73 m(-2), mean 24-h ambulatory blood pressure (A&D TM2420) was 110 +/- 3 and 114 +/- 2 mmHg, and 24-h urinary albumin excretion rate was 961 (range 331-5,727) and 1,578 (476-5,806) mg/24 h in the lisinopril and atenolol groups, respectively. The mean follow-up time was similar, 37 and 35 months in the lisinopril and atenolol groups, respectively. Mean ambulatory blood pressure was equally reduced in the two groups, 12 +/- 2 and 10 +/- 2 mmHg in the lisinopril and atenolol groups, respectively. Glomerular filtration rate declined in a biphasic manner with a faster initial (0 to 6 months) change of 1.25 +/- 0.49 and 0.81 +/- 0.29 ml x min(-1) x month(-1) followed by a slower sustained decline (6 to 42 months) of 0.59 +/- 0.10 and 0.54 +/- 0.13 ml x min(-1) x month(-1) in the lisinopril and atenolol groups, respectively. No significant differences were observed in either initial or sustained decline in glomerular filtration rate between the two groups. Urinary albumin excretion was reduced (% reduction of baseline) more in the lisinopril than in the atenolol group, at 55 (95% CI 29-72) and 15% (-13 to 34), respectively (P = 0.01). In conclusion, the relentless decline in kidney function characteristically found in hypertensive NIDDM patients with diabetic nephropathy can be reduced equally effectively by two antihypertensive treatments, the beta-blocker atenolol and the ACE inhibitor lisinopril. 相似文献
162.
The 20-kDa protein gene is androgen regulated in rat ventral prostate. Intron 1 contains a 130-base pair complex response element (D2) that binds androgen (AR) and glucocorticoid receptor (GR) but transactivates only with AR in transient cotransfection assays in CV1 cells using the reporter vector D2-tkCAT. To better understand the function of this androgen-responsive unit, nuclear protein interactions with D2 were analyzed by DNase I footprinting in ventral prostate nuclei of intact or castrated rats and in vitro with ventral prostate nuclear protein extracts from intact, castrated, and testosterone-treated castrated rats. Multiple androgen-dependent protected regions and hypersensitive sites were identified in the D2 region with both methods. Mobility shift assays with 32P-labeled oligonucleotides spanning D2 revealed specific interactions with ventral prostate nuclear proteins. Four of the D2-protein complexes decreased in intensity within 24 h of castration. UV cross-linking of the androgen-dependent DNA binding proteins identified protein complexes of approximately 140 and 55 kDa. The results demonstrate androgen-dependent nuclear protein-DNA interactions within the complex androgen response element D2. 相似文献
163.
Prostate enlargement in mice due to fetal exposure to low doses of estradiol or diethylstilbestrol and opposite effects at high doses 总被引:7,自引:0,他引:7
FS vom Saal BG Timms MM Montano P Palanza KA Thayer SC Nagel MD Dhar VK Ganjam S Parmigiani WV Welshons 《Canadian Metallurgical Quarterly》1997,94(5):2056-2061
On the basis of results of studies using high doses of estrogens, exposure to estrogen during fetal life is known to inhibit prostate development. However, it is recognized in endocrinology that low concentrations of a hormone can stimulate a tissue, while high concentrations can have the opposite effect. We report here that a 50% increase in free-serum estradiol in male mouse fetuses (released by a maternal Silastic estradiol implant) induced a 40% increase in the number of developing prostatic glands during fetal life; subsequently, in adulthood, the number of prostatic androgen receptors per cell was permanently increased by 2-fold, and the prostate was enlarged by 30% (due to hyperplasia) relative to untreated males. However, as the free serum estradiol concentration in male fetuses was increased from 2- to 8-fold, adult prostate weight decreased relative to males exposed to the 50% increase in estradiol. As a model for fetal exposure to man-made estrogens, pregnant mice were fed diethylstilbestrol (DES) from gestation days 11 to 17. Relative to controls, DES doses of 0.02, 0.2, and 2.0 ng per g of body weight per day increased adult prostate weight, whereas a 200-ng-per-g dose decreased adult prostate weight in male offspring. Our findings suggest that a small increase in estrogen may modulate the action of androgen in regulating prostate differentiation, resulting in a permanent increase in prostatic androgen receptors and prostate size. For both estradiol and DES, prostate weight first increased then decreased with dose, resulting in an inverted-U dose-response relationship. 相似文献
164.
S Satake N Clark D Rimland FS Nolte FC Tenover 《Canadian Metallurgical Quarterly》1997,35(9):2325-2330
Surveillance cultures for vancomycin-resistant enterococci (VRE) are time-consuming and expensive for the laboratory to perform. Therefore, we investigated the use of PCR as an alternative method of detecting and identifying VRE directly in fecal samples. PCR primers directed to vanA, vanB, vanC1, vanC2, and enterococcal ligase genes were used to detect and identify VRE in fecal material obtained by rectal or perirectal swabbing. Although PCR-inhibitory substances were present in DNA prepared directly from the swabs, the inhibitory substances could be reduced by processing the nucleic acid with two commercially available DNA preparation columns. Fecal material from 333 swabs was cultured on several selective agar media before and after broth enrichment. DNA was extracted from the fecal material and was analyzed by PCR. By using all four primer sets, only 59 (67.8%) of the samples were positive for vanA. However, after retesting the negative samples with only the vanA primer set, 77 (88.5%) of 87 specimens that were culture positive for Enterococcus faecium containing vanA were positive by PCR. One specimen was PCR positive for the vanA gene but culture negative for enterococci. The specificity of the vanA assay was 99.6%. PCR analysis of enrichment broth samples with all four primers sets after 15 to 18 h of incubation detected 74 (85.1%) of the 87 culture-positive specimens. The specificity of the vanA assay after the enrichment step was 100%. No vanB-containing enterococci were recovered by culture. Since 16 samples can be tested by PCR in 4 h (including electrophoresis), identification of VRE is possible within 8 h of specimen submission at a cost of approximately $10.12/assay. Thus, PCR may be a cost-effective alternative to culture for surveillance of VRE in some hospitals. 相似文献
165.
CV Fletcher BK Goodroad LM Cummins K Henry HH Balfour FS Rhame 《Canadian Metallurgical Quarterly》1997,41(7):1571-1574
Hyperimmune anti-human immunodeficiency virus immunoglobulin (HIVIG) is an intravenous immunoglobulin prepared from HIV-infected asymptomatic donors with a CD4 cell count greater than 400 cells/microl and a high titer of antibody to HIV-1 p24 protein. Twelve persons with AIDS received four doses of HMG (two at 50 mg/kg of body weight and then two at 200 mg/kg) every 28 days. Pharmacokinetics were evaluated by measurement of anti-p24 antibody. HIVIG was well tolerated, and all participants completed the study. Three subjects who were not receiving Pneumocystis carinii pneumonia (PCP) prophylaxis developed PCP. The mean value for HIVIG clearance was 3.02 ml/kg/day at 50 mg/kg and 3.65 ml/kg/day at 200 mg/kg (P = 0.027); the mean trough antibody titers (reciprocal units) were 1,442 and 4,428, respectively. This study indicates that high titers of anti-p24 antibody can be maintained with a monthly administration schedule of HIVIG and that short-term safety is acceptable. Comparisons to evaluate the therapeutic potential of HIVIG are justified. 相似文献
166.
The presence of the non-selective protein kinase C (PKC) inhibitors, staurosporine (100 nM) and polymyxin B (100 microM) in cultured human RPE cells for more than 24 h triggers apoptotic death. Apoptosis is characterized by a diminishing number of cells, a labelling of nuclei by the TUNEL method and by observable morphological changes. An inhibitor of PKC and cyclic nucleotide-dependent protein kinases, 1-(5-isoquinolinesulphonyl)-2-methyl piperazine (H-7; 100 microM), was without effect, as was the specific PKC inhibitor, calphostin C (100 nM). The PKC-activating phorbol esters, phorbol-12-myristate-13-acetate (PMA; 1 microM) and phorbol-12,13-dibutyrate (PDB; 1 microM) and the non-tumour-promoting phorbol ester, 4 alpha-PMA (1 microM) were without effect, as was the diacyl glycerol analogue, 1,2-dioctanoyl-snglycerol (DOG; 10 microM). The PKC activators did not attenuate the apoptosis induced by staurosporine or polymyxin B. Furthermore, deprivation of glucose and oxygen (simulated ischemia) for 72 h induced apoptosis: this could be prevented by inclusion of 10% (v/v) foetal bovine serum (FBS) but not by a variety of PKC activators. Six PKC isoenzymes were shown to be present in RPE cells (alpha, beta 1, beta 2, delta, epsilon, E) and only the calcium-dependent cPKC levels changed after treatment with staurosporine or simulated ischaemia. Since only the less selective inhibitors of PKC induced apoptosis, it is suggested that PKC is not involved directly in the induction process of apoptosis in RPE cells. It is possible that the staurosporine and polymyxin B-induced effects of apoptosis in RPE cells are triggered by an unknown kinase-dependent pathway, but whether the 'ischaemia'-induced death is related to this same process remains to be elucidated. 相似文献
167.
Adverse reactions to seafood are common and may cause many types of symptoms that are difficult to define. The nature of these reactions are variable including allergic and toxic reactions as well as infectious diseases. The differentiation between these entities is essential in choosing therapy. We describe 9 patients with IgE mediated allergic reactions due to crustaceans and fish diagnosed from case history, clinical findings, skin tests and specific IgE antibodies. Most symptoms of a IgE mediated allergic reaction appear within 30 minutes after ingestion. Characteristics clinical features may include an urticarial rash, gastrointestinal symptoms and even anaphylaxis. In this case immediate therapy with intravenous glucocorticoids, antihistamine and perhaps subcutaneous epinephrine is required. 相似文献
168.
FG La Rosa FS Adams GE Krause AD Meyers J Edwards-Prasad R Kumar CR Freed KN Prasad 《Canadian Metallurgical Quarterly》1997,113(1-2):55-60
In this paper the Authors reviewed the recent literature for a more comprehensive and clear vision of the epidemiological and pathological aspects of retroperitoneal sarcomas. The most effective procedures for a an early and accurate diagnosis were identified. Moreover, the different therapeutic choices were taken into account focusing on those provided of the major potential in terms of oncologically valid treatment. 相似文献
169.
F Mota JH Kanan N Rayment T Mould A Singer BM Chain 《Canadian Metallurgical Quarterly》1997,150(4):1223-1229
We have investigated the expression of the aspartic proteinase cathepsin E and HLA-DR and the presence of HPV16 in normal squamous epithelium (n = 8) and low-grade (n = 21) and high-grade (n = 14) intraepithelial squamous lesions of the uterine cervix. Immunohistochemistry of cervical biopsies revealed that up-regulation of cathepsin E expression was related to increasing severity of the cervical intraepithelial neoplasia (CIN). Up-regulation of protein was associated with increased message as assessed by in situ hybridization. Langerhans cells and the majority of koilocytes did not express detectable cathepsin E levels. Although there was also an up-regulation of HLA-DR expression by cervical keratinocytes in cervical intraepithelial neoplasia lesions, as determined by immunohistochemistry, no significant correlation was found between HLA-DR and cathepsin E expression in these lesions; neither was expression of cathepsin E correlated to the presence of HPV16, detected by polymerase chain reaction. The expression of cathepsin E, an aspartic proteinase that is reported to play a role in antigen processing for presentation by class II major histocompatibility complex molecules, is associated with cellular dedifferentiation in cervical intraepithelial neoplasia. 相似文献
170.
L Tonella BJ Walsh JC Sanchez K Ou MR Wilkins M Tyler S Frutiger AA Gooley I Pescaru RD Appel JX Yan A Bairoch C Hoogland FS Morch GJ Hughes KL Williams DF Hochstrasser 《Canadian Metallurgical Quarterly》1998,19(11):1960-1971
The combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), computer image analysis and several protein identification techniques allowed the Escherichia coli SWISS-2DPAGE database to be established. This is part of the ExPASy molecular biology server accessible through the WWW at the URL address http://www.expasy.ch/ch2d/ch2d-top.html . Here we report recent progress in the development of the E. coli SWISS-2DPAGE database. Proteins were separated with immobilized pH gradients in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. To increase the resolution of the separation and thus the number of identified proteins, a variety of wide and narrow range immobilized pH gradients were used in the first dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride membranes and spots were visualized by amido black staining. Protein identification techniques such as amino acid composition analysis, gel comparison and microsequencing were used, as well as a recently described Edman "sequence tag" approach. Some of the above identification techniques were coupled with database searching tools. Currently 231 polypeptides are identified on the E. coli SWISS-2DPAGE map: 64 have been identified by N-terminal microsequencing, 39 by amino acid composition, and 82 by sequence tag. Of 153 proteins putatively identified by gel comparison, 65 have been confirmed. Many proteins have been identified using more than one technique. Faster progress in the E. coli proteome project will now be possible with advances in biochemical methodology and with the completion of the entire E. coli genome. 相似文献