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71.
葛淼 《吉林大学学报(医学版)》1999,25(4):510-512
目的:为制定中国健康中青年女性全血比粘度参考值的统一标准提供科学依据。方法:收集了中国各地用毛细管法测定的健康中青年女性全血比粘度参考值,并对其与海拔高度的关系进行了研究。结果:发现随着海拔高度的逐渐增大,健康中青年女性全血比粘度参考值也在逐渐增大,相关性很显著。用一元回归分析的方法推导出一个回归方程。结论:如果知道了中国某地的海拔高度,就可以用回归方程估算这个地区的健康中青年女性全血比粘度参考值。 相似文献
72.
人工股骨头置换术的应用解剖 总被引:1,自引:0,他引:1
目的:为临床人工股骨头置换术人工假体的选择、安装及定位提供可靠的解剖学参数。方法:对250例(左右各125例)正常成人股骨头、股骨颈、大转子与外上髁间距进行观测,并得出转子髁间距与股骨头最大径、股骨头颈前长和股骨头颈后长的相关系数和回归方程。结果:股骨头最大径为4.39±0.31cm,股骨头颈后长为6.89±0.49cm,股骨头颈前长为6.18±0.43cm,大转子与外上髁间距为34.40±1.79cm。结论:采用本文作者提供的方法选择、安装人工假体准确、实用、方便 相似文献
73.
Rozniecki JJ Dimitriadou V Lambracht-Hall M Pang X Theoharides TC 《Brain research》1999,840(1-2):1-15
The effects of changes in temperature on primary and secondary endings of isolated cat muscle spindles were investigated under ramp-and-hold stretches and different degrees of pre-stretch. Temperature-induced alterations of the discharge frequency were compared over a temperature range of 25–35°C. Both primary and secondary endings responded to warming with increasing discharge frequencies when the spindle was pre-stretched by 5–10% of its in situ length. The following differences between the temperature effects on primary and secondary endings were observed: (1) The temperature coefficients (Q10) obtained from the discharge frequencies during the dynamic and static phase of a stretch were similar for endings of the same type, but they were larger in primary endings (range of Q10: 2.3–3.3; mean: 2.9) than in secondary endings (range of Q10: 1.6–2.2; mean: 2.0); (2) With primary endings, but not with secondary endings, the temperature sensitivity (imp s−1 °C−1) was larger during the dynamic phase than during the static phase of a stretch; (3) In primary endings, the fast and slow adaptive components occurring in the discharge frequency during the static phase of a stretch clearly increased with warming while in secondary endings, the slow decay was less affected, and the fast decay showed no change; (4) In relaxed spindles, the excitatory effect of warming was overlaid by a strong inhibitory effect as soon as the temperature exceeded about 30°C, resulting in an abrupt cessation of the background activity in most secondary endings, but not usually in primary endings. In general, warming induced an enhanced stretch sensitivity in both types of ending, and additionally an inhibitory effect that is obvious only in secondary endings of relaxed spindles. The different effects of temperature on the discharge frequency of primary and secondary afferents are assumed to be caused by different properties of their sensory membranes. 相似文献
74.
短小芽胞杆菌E601抗电离辐射性的研究 总被引:1,自引:0,他引:1
目的 短小芽胞杆菌E601 已在中国确定为辐射灭菌指示菌。为使指示菌在灭菌过程中的应用标准化、规范化,保证灭菌质量,需要对其固有抗辐射性和影响因素,以及如何制备抗辐射稳定的生物指示剂作详尽研究。方法 应用钴60γ射线和高能电子束对短小芽胞杆菌E601 进行辐照,测定不同条件下的D10 值。结果 ①因载体、介质不同,D10 值变化在1 .60 ~2.53kGy 之间。②不同温度下保存一年,指示菌片芽胞抗辐射性无明显变化。但随着保存时间延长,菌片上存活菌数逐渐减少。③载体、介质影响存活率,电子束与钴60 结果一致。结论 短小芽胞杆菌D10 值在1 .60~2.53kGy 之间,且抗性稳定。本试验条件下制备的可溶性菌片抗力高,D10 值为2 .53kGy,可长期保存,适宜作指示剂应用 相似文献
75.
P. M. L. A. van den Bemt A. C. G. Egberts A. W. Lenderink J. M. Verzijl K. A. Simons W. S. C. J. M. van der Pol H. G. M. Leufkens 《European journal of clinical pharmacology》1999,55(2):155-158
Objective: This study investigated the relative value of adverse drug events reported by doctors, nurses and patients.
Methods: The study was conducted on a total of four wards: the paediatric and internal medicine wards (including geriatric patients)
of two peripheral hospitals in the Netherlands. Adverse drug events were collected by spontaneous reporting (doctor and nurse
reports) and by daily ward visits, during which the patients were interviewed by a hospital pharmacist (patient reports).
Criteria for relative value of the reported adverse drug events were the number of potentially serious reactions, the number
of reactions not mentioned in the patient information leaflet and the number of reactions reported to new drugs (5 years or
less on the Dutch market). No formal causality assessment was applied.
Results: Over a period of 2 months in 1996 (Hospital I) and 2 months in 1997 (Hospital II) a total of 620 patients were included
in the study and adverse drug events were reported in 179 (29%) of these cases. Doctors reported a statistically significant
larger number of serious (26% of all doctor reports; odds ratio (OR) 3.2; confidence interval (CI) 1.2–8.7) and unknown (39%;
OR 2.5; CI 1.0–6.0) adverse drug events than patients themselves during the daily ward visit. Doctors also reported more serious
and unknown adverse drug events than nurses. Adverse reactions to new drugs were reported during the daily ward visit only
(8% of all daily ward visit reports).
Conclusion: This study reconfirms that doctors are the main source for reports of serious and unknown adverse drug events in hospitalized
patients. However, patients themselves seem to report more adverse reactions to new drugs (during the daily ward visit). By
focusing on patients using new drugs, the daily ward visit might become cost-effective. This needs to be explored in future
studies.
Received: 10 September 1998 / Accepted in revised form: 30 November 1998 相似文献
76.
In this prospective study, birth weight of 304 babies born at Kamla Nehru Hospital Pune during study period was recorded.
From these 304 babies, babies with birth weight above 2000 grams were selected (260 babies) to prepare growth velocity curves.
Daily weight of these 260 babies was recorded for 30 days. The mean birth weight of study population was 2742.5 grams. Among
the daily weight recorded babies, all the babies lost weight ranging from 92 to 218 grams (mean 121 grams) after birth. The
weight loss continued upto 5 days. Days required to gain weight equal to birth weight ranged from 5 to 13 days. Total weight
gain observed in 30 days was 734.7 grams. Predictive value of these curves was tested in 49 infants. Deviation upto 50 grams
of predicted birth weight from actual birth weight was observed in 90% of babies on day-2, 79% on day-4, 65% on day-8 and
39% on day-30. 相似文献
77.
The location of amino acids in soluble or membrane proteins is related to the hydrophobicity of the side chains. Amino acid hydrophobicity values are based upon the thermodynamics of transfer from an aqueous to a nonaqueous environment. However, for certain hydrophilic residues uncertainty exists on the appropriate hydrophobicity values. We have measured the octanol- water partition coefficients (P
o/w) of tripeptides of the sequence N-14-C-acetyl-Ala-JT-Ala-NH-tButyl (AcAlaXAlaNHtButyl), where the central residue X was either Gly , Ala, Phe, Trp, Pro, His, Asp, or Glu. The P
o/w for the tripeptides agreed reasonably well with values calculated by the fragment method of D. J. Abraham and A. J. Leo (Proteins Struct. Func. Gen. 2, 130–152, 1987). The log P
o/w of the uncharged form was 1.6,2.7, and 2.5 greater than the log P
o/w of the ionized form for the His, Asp, and Glu peptide, respectively. The new data on the pH dependence of the ionizable side chains, His, Asp, and Glu, should result in better prediction of the partition coefficient of peptides as a function of pH. The thermodynamic parameters were determined from the temperature dependence of partitioning. In the temperature range studied (2 to 65°C) the transfer of tripeptides from water to octanol was entropy governed except for the ionized peptides. A heat capacity term was necessary to account for the transfer of tripeptides containing non polar residues. The heat capacity change for transfer from water into octanol was –45, –73, –81, and –88 cal/mol K for Ala, Phe, Trp, and Pro peptides, respectively. Peptides containing Gly, His (pH 7.2), and the uncharged forms of Asp, Glu, and His did not show a significant change in heat capacity. The side-chain contribution of the central residue X (G
X) to the free energy of transfer was obtained from the difference between the free energy o f transfer of the peptide containing the central residue X and the Gly peptide; G
X = G
(AcAlaGlyAlaNHtButyl) - G (AcAlaGlyAlaNHtButyl). The relative order of hydrophobicity of the side chains correlated well with previous studies. However, a significant difference was found for the absolute hydrophobicity between the present study and experimental data on N-acetyl amino acid amide derivatives (J. Fauchere and V. Pliska, Eur. J. Med. Chem. 18(4), 369–375, 1983). The G
X values at pH 7.2 were 0, –0.13, –2.19, –2.52,–0.29, –0.16, 3.50, and 3.12 kcal/mol for Gly, Ala, Phe, Trp, Pro, His, Asp, and Glu, respectively. These hydrophobicity values in a tripeptide environment provide suggested values for a hydrophobicity scale. 相似文献
78.
咪喹莫特脂质体与乳膏体外经皮扩散行为的比较 总被引:4,自引:1,他引:4
采用中和法制备咪喹莫特脂质体,研究了其体外经皮扩散行为并与咪喹莫特乳膏进行比较。制得的脂质体平均粒径为855nm,跨距为1.65,能经皮缓慢扩散,皮层的局部贮药量比之乳膏有增加,可减少药物全身吸收。 相似文献
79.
80.
目的:探讨开展乳腺癌前哨淋巴结活检(Sentinel lymph node biopsy,SLNB)的必要性、可行性、准确性及临床应用价值。方法:对45例临床、B超及钼靶检测腋窝LN阴性的原发乳腺癌患者,术中在原发肿瘤周围注射专利蓝进行腋窝淋巴结切除(SLNB),随后行腋窝淋巴结清扫(ALND)。术中对部分SLN、术后对全部LN行常规病理检查。结果:45例患者中41例检测到SLN,成功率91.1%;假阴性率为6.66%,SLNB总的敏感性是93.3%,特异性是96.1%;总的阳性和阴性预测值分别是93.3%和96.1%。结论:乳腺癌SLNB是一项有实用价值的新技术,目前国内外仍在研究阶段,随着研究的扩大与深入将有可能取代常规的ALND。 相似文献