新复合纤维蛋白胶可注射性磷酸钙人工骨的理学特性

目的:检测纤维蛋白胶复合β-磷酸三钙/磷酸二氢钙复合人工骨材料的物理学性能,评价纤维蛋白胶对β-磷酸三钙/磷酸二氢钙骨水泥性能的影响,以及其作为注射型复合人工骨用于修复骨缺损的可行性。方法:实验于2006-12/2007-06在南方医科大学珠江医院中心实验室和华南理工大学生物材料实验室完成。①材料:β-磷酸三钙由上海瑞邦生物材料有限公司提供,磷酸二氢钙为东泰化工赠,纤维蛋白胶购自广州倍绣生物技术有限公司。②复合材料制备:将β-磷酸三钙/磷酸二氢钙骨水泥按3∶1的比例充分混合后,与纤维蛋白胶按凝固后的体积2∶1体积比混合,制成复合人工骨材料。③观察指标:测定复合材料的凝固时间,抗压强度,抗稀散性能,并用扫描电镜观察其煅烧前后的显微结构特征,以未加纤维蛋白胶的磷酸钙水泥为对照(CPC组)。结果:复合人工骨材料的平均初凝时间长于CPC组(P<0.004),终凝时间在初凝时间后2～4 min;复合材料的抗压强度为(14.72±1.81)MPa。复合材料较CPC组有良好的抗稀散性能,扫描电镜发现,纤维蛋白胶贯穿于磷酸钙水泥晶体间,并将磷酸钙水泥晶体紧密连接。煅烧后复合材料的孔径有增大,空隙率为57.28%,并且微孔之间有空隙互相贯通。结论:该骨水泥复合材料凝固时间符合临床操作的需要;抗压强度达到松质骨强度的要求;煅烧后磷酸钙水泥的空隙率明显提高,有利于材料的降解。     

薄层扫描法测定黄芪生脉颗粒中黄芪甲甙含量

目的：制订黄芪生脉颗粒中黄芪甲甙含量测定方法。方法：双波长薄层扫描法，经乙酰洗涤、正丁醇提取和Ｄ１０１大乳吸附树脂柱层析法制备样品，以氯仿－甲醇－水（１３：７：２）下层液为展开剂，检测波长为５１０ｎｍ，参比波长为７００ｎｍ。结果：加标回收率平均为９８．７％（ＲＳＤ＝２．０％，ｎ＝６），标准曲线ｒ＝０．９９６６，重复性ＲＳＤ＝１．４％（ｎ＝５），精密度ＲＳＤ＝２．０％（ｎ＝６）。结论：方法稳定、可靠     

Meniscal injuries: detection using MR imaging

Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears.     

Chlorpropamide-induced pure white cell aplasia

We investigated the mechanism for isolated agranulocytosis and marrow pure white cell aplasia in an elderly man receiving 0.5 to 1.0 g per day of chlorpropamide (Chl) without other toxic drug exposure or overt systemic illness. Patient marrow revealed an absence of recognizable granulocytic precursors; megakaryocytes and erythroid precursors were normal. The WBC count was 1800/mm3 on admission with only 2% neutrophils; the absolute neutrophil count first exceeded 500/mm3 on the 17th day following cessation of Chl. A serum Chl level on admission was 100 micrograms/mL (acute phase, AP); no Chl was detected in serum (convalescent phase, CP) assessed on the 22nd hospital day. Antineutrophil antibodies were not detected, and T cell depletion failed to augment patient in vitro granulopoiesis. Patient AP serum produced potent complement-mediated inhibition (87% +/- 7%) of autologous granulocyte progenitors (CFU-GM) with minimal inhibition of erythroid (11% +/- 5%) or multipotent (5% +/- 4%) progenitor cells. Selective inhibition by patient AP serum of CFU-GM (74% +/- 11%) was also seen against two allogeneic marrows. Patient CP serum no longer inhibited (6% +/- 4%) autologous CFU-GM. Addition of Chl (5 to 120 micrograms/mL) to CP serum but not to control serum resulted in potent drug concentration-dependent complement-mediated inhibition of autologous and allogeneic CFU-GM. Inhibition of CFU-GM in the presence of Chl was no longer demonstrable following immunoabsorbent removal of IgG from patient serum. Patient serum in the presence of Chl had limited activity against morphologically recognizable marrow granulocytic precursors in a microimmunofluorescence assay. These results are most consistent with the development of Chl-dependent, selective antibody-mediated immune inhibition of granulopoiesis.     

Fat and breast cancer

Breast cancer mortality and incidence in different countries show a strongly positive correlation with the per caput consumption of fat. In addition, the disease has increased among the Japanese, both in Japan and in the United States, and in both groups fat consumption has been increasing. In contrast, both case-control and prospective studies have on the whole failed to confirm the relationship. Despite these negative findings, the hypothesis that fat causes breast cancer has continued to be popular. The evidence for fat as a cause of breast cancer seems to have been exaggerated, and insufficient attention given to alternative explanations for the geographical correlations and for the changes among the Japanese in the frequency of the disease. These include the effects on breast cancer risk of body weight, body size, age at menarche (all influenced by excess calories) and age at the birth of the first child, as well as effects of obesity on the fatality rate in breast cancer. Evidence is lacking that the source of calories is important.     

Factors associated with childhood cancer in a national cohort study

Information on 16,193 infants delivered in Great Britain in one week of April, 1970 was collected by midwives at the birth and during the first 7 days of life. Using multiple sources, 33 children developing cancer by 1980 were identified from this cohort, giving an incidence of 2.04 per 1,000 total births by the age of 10. Comparisons of these 33 children were made with 99 controls, three for each index case, matched on maternal age, parity and social class. Statistically significant associations were initially found with maternal X-rays and smoking during pregnancy, and the use of analgesics such as pethidine during labour, confirming the findings of retrospective case-control studies. Unexpected statistically significant associations were found with delivery of the child outside term, and drug administration in the first week of life. The latter was found in the absence of an association with neonatal abnormalities in the child and relates mostly to the administration of prophylactic drugs such as vitamin K. Logistic regression involving the whole cohort showed independent statistical associations with maternal smoking (OR 2.5), and drugs to the infant (OR 2.6). After adjusting for these factors no other statistically significant associations were found.     

Ethnic composition, age and sex, together with location and standard of housing as determinants of HLTV-I infection in an urban Trinidadian community

The presence of antibody to human T-cell leukaemia virus (HLTV-I) has been assessed in 2,143 men and women who represent 83% of all adults aged 35 to 69 years resident in a defined urban community in Trinidad. Individuals of African descent had a higher sero-positivity rate (7.0%) than those originating from India (1.4%), Europe (0%) or of mixed descent (2.7%). Women were infected more frequently than men, and the prevalence of infection increased with age in both sexes. Sero-positivity rates were significantly increased in adults who lived in housing of poor quality (p less than 0.001) or close to water courses (p less than 0.025). These data and others raise the possibility that one route of HLTV-I transmission may be via insect vectors under particular domestic circumstances.     

Lumbar iohexol myelography and diagnostic lumbar puncture. Headache and associated side effects in relation to neurological signs and diagnosis, previous mental symptoms and pain history

Various possible risk factors for postlumbar puncture (and postiohexol-myelographic) headache and associated side effects were analysed. Headache and nausea occurred significantly more often in patients without clinical findings than in those with findings. We found significantly different incidences of severe headache and nausea between diagnostic subgroups after a lumbar puncture. The greatest headache incidence was found in patients without a definite neurological diagnosis, while nausea occurred most frequently in patients with various painful disorders. Following iohexol myelography, nausea occurred most often in patients who had a history of previous mental symptoms and in patients with a history of previous headache disorders. Mental symptoms were more frequently reported in patients who also had experienced mental symptoms previously. The relationship between side effects and negative clinical findings was stronger than the relationship between side effects and previous mental symptoms.     

核、膜蛋白的基因能抑制禽类流感病毒及其重组株的繁殖

对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。     

Rotator cuff lesions of the shoulder: evaluation by direct sagittal CT arthrography

Direct sagittal computed tomographic scanning (DSCT) of the shoulder was performed in 42 symptomatic patients, six healthy volunteers, and two cadaver shoulders. Axial CT scanning and double-contrast arthrography with plain radiographs were performed in 41 patients for comparison. DSCT enabled correct identification of 27 of 29 lesions in 24 patients. Seventeen patients had normal shoulders. Axial CT scanning and DSCT together enabled correct identification of all lesions and were markedly superior to plain-film arthrography. DSCT enabled diagnosis of all cases of complete rotator cuff tear plus three cases of incomplete tear and three of rotator cuff atrophy not identified by the other techniques. Axial CT scanning was better than DSCT for diagnosis of Bankart lesions.