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121.
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   
122.
The relation between sexual function and serum free testosterone (fT) levels, which represent the active fraction of circulating testosterone, was evaluated. Two groups of impotent male subjects with mild hypogonadism were treated with oral testosterone undecanoate (TU); these men presented with tT/luteinizing hormone (LH) ratio and tT levels at the lower limits of normal. The first group had serum fT below 6.6 ng/ml, considered the lower normal value, according to our laboratory method, whereas the second group had normal fT limits. Administration of TU improved sexual function only in impotent men with low fT levels, but not in subjects with normal fT levels, even though the tT levels and the tT/LH ratio of the two groups were not significantly different. The results of our study suggest the presence of a minimun serum fT threshold, lying near the lower normal range, which determines the male sexual function. Moreover, serum fT levels were a more sensitive index than tT for identifying impotent men who can be successfully treated with androgens.  相似文献   
123.
Electrical stimulation of the phrenic nerve afferents evoked excitatory responses in the right inferior cardiac sympathetic nerve in chloralose-anaesthetized cats. The reflex was recorded in intact and spinal cats. The latency and threshold of the volley recorded from the phrenic nerve as well as of the cord dorsum potentials evoked by electrical stimulation of the phrenic nerve indicated that group III afferents were responsible for this reflex. The phrenicocardiac sympathetic reflex recorded in intact cats was followed by a silent period. The maximum amplitude of the reflex discharges was 800 microV, the latency was 83 ms and the central transmission time 53 ms. Duration of the silent period lasted up to 0.83 s. In spinal cats the reflex was recorded 5.5-8 h after spinalization. The maximum amplitude of the spinal reflex discharges ranged from 22 to 91 microV and the latency from 36 to 66 ms.  相似文献   
124.
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   
125.
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   
126.
Abstract Maxillary and mandibular anterior permanent teeth in 38 children aged 7–12 years were examined 2 × with an interval of 2 years to determine whether spontaneous facial/lingual tooth position changes were related to alterations of the widths of keratinized and attached gingiva and the clinical crown height. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study casts from the baseline and 2-year examinations were used to measure clinical crown height and tooth position. The results showed that significant alterations in the widths of the keratinized and attached gingiva took place when the teeth changed positions in facial or lingual directions. The changes in gingival widths could to some extent be coupled to changes in clinical crown height. In teeth moving lingually, the gingival widths increased and the clinical crown height decreased. In teeth moving facially, the gingival widths decreased, and the facial gingiva sometimes receded. These gingival alterations call for examination of the facial gingiva as part of the monitoring of the development of the permanent dentition.  相似文献   
127.
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   
128.
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77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成.  相似文献   
129.
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   
130.
The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases.  相似文献   
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