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81.
AIMS: To compare long-term (1 year) efficacy and safety of pioglitazone and gliclazide in patients with Type 2 diabetes. METHODS: This was a double-blind, multicentre, comparative, parallel group trial in 283 patients with Type 2 diabetes, who were randomized to receive 1-year treatment with pioglitazone 30-45 mg/day or gliclazide 80-320 mg/day. Drug dose was titrated on the basis of self-monitored blood glucose (SMBG) measurements and HbA1c values. The 1-year changes in HbA1c, fasting blood glucose (FBG), insulin, HOMA-S (HOmeostatic Model Assessment) and SMBG were compared. In a subgroup of patients (n = 10), systemic glucose production and utilization were determined by a combination of isotopic (deuterated glucose) and clamp techniques. RESULTS: In both groups, there were similar decreases in HbA1c (pioglitazone: -0.79%; gliclazide: -0.79%) and FBG (pioglitazone: -1.0 mmol/l; gliclazide: -0.7 mmol/l), whereas the slope of the reduction of fasting blood glucose was different between groups (P = 0.004). Insulin levels as well as insulin resistance assessed using HOMA-S decreased significantly only after pioglitazone treatment (-11.94 pmol/l and -1.03, respectively, both P = 0.002 vs. baseline). A significantly greater reduction in systemic glucose production was observed in the pioglitazone group (-2.48 micromol/kg/min, P = 0.042) than in the gliclazide group (-1.02 micromol/kg/min). A few, mild adverse events occurred in both groups. CONCLUSIONS: A comparable decrease in HbA1c and FBG was observed with pioglitazone and gliclazide. However, with pioglitazone there was a continuous decrease in FBG over 1 year, whereas gliclazide failed to maintain a similar trend. This favourable effect of pioglitazone was due to its insulin-sensitizing effect and ability to decrease systemic glucose production. 相似文献
82.
83.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献
84.
Franco Rilke M. D. F. R. C. Umberto Veronesi M. D. Alberto Luini M. D. Cristina Brambilla M. D. Viviana Galimberti M. D. Stefano Zurrida M. D. Silvana Pilotti M. D. M. I. A. C. Silvana Di Palma M. D. Roberto Zucali M. D. Laura Lozza M. D. 《The breast journal》1996,2(3):176-180
Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinomas. It may be possible to further limit the extent of resection (or expand the indication for breast conservation) by the application of preoperative chemotherapy and radiotherapy. We explored the feasibility of this in a pilot study.
Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.
In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored. 相似文献
Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.
In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored. 相似文献
85.
This report is a retrospective clinical randomized study carried out on 114 cases of incidental prostatic carcinoma aged 55-87 years, 58 untreated and 56 treated with cyproterone acetate (CPA 200 mg/day) for 6 months, immediately after surgery. 78 cases were staged A1 and the remaining 36 A2. In stage A1, 75 cases were histologically graded G1, and 3 G2, whereas in stage A2, 7 cases were G1, 19 G2 and 10 G3. Moreover, flow cytometric DNA analysis showed in A1 20 G1 carcinomas with nuclear diploidy and 3 G2 with nuclear aneuploidy, in stage A2, 4 G3 tumors with nuclear aneuploidy. During the 4-year follow-up, 25/28 patients of the untreated group and 15/56 of the CPA-treated group were found in progression. In A1, progression was found in 6/37 untreated patients and 5/41 CPA-treated, whilst in A2 progression was observed in 19/21 untreated patients and in 10/15 treated with CPA. The critical period for progression was between the 2nd and 3rd year of follow-up. In A1, therefore, 6 months of therapy with CPA does not modify the progression rate, which is significantly improved in A2 (66% in the treated and 90% in the untreated group) during the first 30 months of follow-up. The prognosis may probably be further improved by continuing endocrine therapy. 相似文献
86.
E Cianchetti R Cotellese A Dell'Osa M Nardi A D'Aulerio L Puglielli P Di Sebastiano C Saragani A M Napolitano 《Minerva chirurgica》1990,45(17):1093-1096
A case series of 5 male patients afflicted with breast carcinoma is reported. The Authors describe symptomatology, diagnostic iter, principles of surgical treatment and results. Underlined is the wider surgical demolition in male breast cancer in comparison with females, even if natural history and biological conduct are comparable. This is because in male breast carcinoma the local and remote infiltration is more rapid than female for the less development of breast gland. Finally, indications for radiochemotherapy are comparable to female breast cancer. 相似文献
87.
大鼠肝细胞Ⅰ,Ⅲ型前胶原基因表达及PDGF的影响 总被引:3,自引:1,他引:2
目的观察大鼠肝细胞Ⅰ,Ⅲ型前胶原基因的表达及PDGF对其表达的影响.方法应用原位杂交技术检测分离培养的SD大鼠肝细胞(n=30)内Ⅰ,Ⅲ型前胶原基因的表达.同时观察10μg/L(n=30)和30μg/L(n=30)PDGF促进前胶原基因表达的作用.测定基因表达颗粒总面积占细胞总面积的百分比,并作比较分析.结果无论正常肝细胞或是在两种浓度的PDGF存在时,肝细胞内均可见到Ⅰ,Ⅲ型前胶原基因的表达.正常肝细胞Ⅰ,Ⅲ型前胶原基因表达面积的百分比(%)为77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成. 相似文献
88.
膜荚黄芪毛状根中异黄酮成分的反相高效液相色谱分析 总被引:9,自引:1,他引:8
对膜荚黄芪毛状根中6种异黄酮成分进行了反相高效液相色谱法测定。色谱柱为NucleosilC18柱,流动相为甲醇—水(3∶2和3∶1,v/v),检测波长为254nm和280nm。6种异黄酮成分为:10-羟基-3,9-二甲氧基紫檀烷,(3R)8,2’-二羟基-7,4’-二甲氧基异黄烷,芒柄花素(7-羟基-4’-甲氧基异黄酮),8,3’-二羟基-7,4’-二甲氧基异黄酮,2’-羟基-3’,4’-二甲氧基异黄烷-7-O-葡萄吡喃糖甙,毛蕊异黄酮(7,3’-二羟基-4’-甲氧基异黄酮)。异黄酮浓度在2.5~12.5μg范围内与峰面积有良好的线性关系;加样回收率为96.47%~103.33%;精密度试验相对标准偏差为2.57%~6.52%;测得黄芪毛状根中6种异黄酮成分的含量在0.0005%~0.0065%之间。 相似文献
89.
Previous exposure to a dopaminergic agonist (priming) strongly potentiates contralateral turning behaviour in response to D1 and D2 agonists in unilaterally 6-hydroxydopamine-lesioned rats. In order to study the influence of priming on the behavioural interaction of D1 and D2 receptors, we examined the effect of selective D1 and D2 receptor blockade on the contralateral turning induced by the mixed D2/D2 agonist apomorphine in drug-naive and primed 6-hydroxydopamine-lesioned rats. In drug-naive rats, apomorphine induced a dose-related, apparently monophasic rotation curve. Administration of selective D1 (SCH 23390) or D2 (raclopride) antagonists abolished the contralateral turning induced by 0.1 mg/kg of apomorphine and partially inhibited that induced by 0.5 mg/kg. In primed rats low doses of apomorphine (0.05 mg/kg) induced an apparently monophasic contralateral turning which was reduced by D1 receptor blockade and completely abolished by D2 receptor blockade; a higher dose of apomorphine (0.1 mg/kg) instead elicited a biphasic (two-peak) pattern of rotation. After this dose of the agonist, blockade of D1 or D2 receptors abolished the second peak of rotation but, while D1 blockade reduced the total number of turns, D2 blockade failed to do so. Quantitative analysis of the interaction between D1 and D2 receptors in the overall turning effect, as well as in the time-course of turning behaviour, indicates that D1 and D2 receptors interact not only positively but also negatively. After higher doses of apomorphine, both negative and positive interactions take place sequentially during the time-course of apomorphine action and provide a clue for explaining the two-peak pattern of rotation observed after apomorphine in rats previously exposed to the drug. 相似文献
90.
P L Di Patre 《Medical hypotheses》1991,34(2):165-170
A theory is presented here in the attempt to explain why Alzheimer's disease (AD) primarily affects areas of the human brain that have been acquired recently in phylogenesis. Disturbances in cytoskeletal function are proposed to play a fundamental role in triggering the sequence of pathologic events leading to the occurrence of AD-related histopathological markers and to the degeneration and death of neurons. These deficits are supposed to occur more likely in neuronal populations that possess a high degree of plasticity, the substrate of memory functions, and that constitute, in fact, the phylogenetically new telencephalic regions of the human brain. 相似文献