How residents spend their time in clinic and the effects of clerical support

The authors conducted a time study of residents in clinic to determine the effects of providing clerical assistance. The residents recorded their activities at 5-minute intervals at baseline and six months after hiring three clerical assistants. Before and after introduction of the clerical assistants, approximately 40% of the time was devoted to direct interaction with patients. Statistically significant improvements were observed in the availability of medical records (89% vs 100%) and the time spent looking up test results (5% vs 3% of the clinic time). The residents felt the clerical assistants greatly improved their clinic experience and the quality of patient care Received from the Section of General Internal Medicine and the Health Services Research and Development Field Program, Seattle Veterans Affairs Medical Center, and the Division of General Internal Medicine, University of Washington, Seattle, Washington. Presented at the annual meeting of the Society of General Internal Medicine, Washington, DC, April 30, 1993.     

抗三尖杉酯碱HL－60细胞的抗程序性细胞死亡及其克服

三尖杉酯碱（ｈａｒｒｉｎｇｔｏｎｉｎ，ＨＴ）是中国产植物海南粗榧（ＣｅｐｈａｌｏｔａｘｕｓｈａｉｎａｎｅｎｓｉｓＬｉ）中提取的一种抗肿瘤药物，对急性粒细胞白血病、急性单核细胞白血病有较好疗效（１）。三尖杉酯碱可非常有效地诱导敏感ＨＬ－６０细胞程序性死亡（ａｐｏｐｔｏｓｉｓ，Ａｐｏ）（２，３）。但超过半致死剂量（ＩＣ５０）近百倍的ＨＴ却不能诱导抗三尖杉酯碱细胞ＨＴ１２程序性死亡。如用维拉帕米（ｖｅｒａｐａｍｉｌ，Ｖｐ）１０μｇ·ｍｌ－１逆转多药抗性后，ＨＴ虽可诱导ＨＴ１２细胞程序性死亡，但与敏感细胞相比，出现程序性细胞死亡的时间大大推迟，用药浓度也提高约１０倍。这些结果提示：程序性细胞死亡可能作为肿瘤细胞是否已形成抗药性的标志之一，同时也说明程序性细胞死亡相关因子可能参与肿瘤细胞抗药性的形成。     

Thalamo-cortical processing of vibrissal information in the rat. II. spatiotemporal convergence in the thalamic ventroposterior medial nucleus (VPm) and its relevance to generation of receptive fields of S1 cortical "barrel" neurones

One hundred and twenty-six cells, sampled in the vicinity of the D1 barreloid in the ventroposterior medial nucleus of the thalamus, were tested for magnitude and latency of response to brief deflections (3 ms; 1.14 degrees) of vibrissae in adult rats under controlled conditions of light urethane anaesthesia. Similar results were achieved for D1 and non-D1-dominant cells. D1-dominant cells (N = 76) responded to the centre-receptive field (D1) vibrissa with a mean of 1.08 spikes per stimulus at modal latencies of 3-12 ms (inter-quartile range 4-5 ms) and to surrounding vibrissae with a mean of 0.26 spikes per stimulus at latencies of 3-41 ms (interquartile range 5-8 ms). Surround-receptive fields showed extensive overlap but were reduced and finally eliminated by deepening anaesthesia. A cell-by-cell analysis showed no correlation between latency and response magnitude for responses to surround vibrissae. Response magnitudes to the surround- and centre-receptive field inputs for D1-dominant barrel cells were some 2.5- and 1.7-fold greater, respectively, than for thalamic cells under identical experimental conditions. The latencies to centre- and surround-receptive field inputs for D1-dominant barrel cells were 2.5 and 10-20 ms later than for thalamus, respectively. These data on a mismatch of latencies for surround- and centre-receptive fields in thalamus and cortex support the notion that surround-receptive fields of cortical barrel cells are almost entirely constructed intracortically during light anaesthesia (Armstrong-James et al., '91), although it is argued that surround-receptive fields of thalamic cells conceivably could be relayed in other cortical states or serve a role in plasticity.     

The Massachusetts Mental Health/Substance Abuse managed care program: The providers' view

This paper reviews the differential impacts of the Massachusetts Mental Health/Substance Abuse Program from the viewpoints of the providers. The program is a state wide managed care system, providing services for adult and children's mental health and substance abuse care. Interviews found that even though the severity of illness of most clients in the program was greater than before managed care, most providers believed that the quality of care and access to services for these clients was the same or better than before managed care. Providers' concerns about the future suggested that savings in a managed care program primarily occur in its initial stages and that future reductions have the potential for negative impacts upon clients and providers.Funding for this study was provided by the Massachusetts Division of Medical Assistance (James O. Michel, Director of the Mental Health/Substance Abuse Program.)     

Paranasal sinus hemorrhage: evaluation with MR imaging

Computed tomography (CT) and magnetic resonance (MR) imaging were performed in ten patients with paranasal sinus hemorrhage after trauma. Acute or subacute hemorrhage was detected on MR images by using T1- and T2-weighted imaging to identify the chemical state of the blood and to differentiate blood from mucosal thickening and sinus effusion. Surgical proof of intrasinus hemorrhage was obtained in only two cases. Displaced fractures, associated cerebral contusions, and traumatic encephalocele were well shown on MR imaging. Nondisplaced and minimally displaced fractures were better evaluated with CT.     

The Importance of Surface Charge in the Optimization of Antigen–Adjuvant Interactions

The adsorptive behavior of the recombinant malarial antigens R32tet32, R32NS181 and NS181V20 to aluminum hydroxide and aluminum phosphate gels was studied as a function of pH and buffer ions. The Plasmodium falciparum antigen, R32NS181, and the P. vivax antigen, NS181V20, with isoelectric points (pI) of 5.9 and 5.5, respectively, adsorbed readily to the positively charged boehmite form of aluminum hydroxide gel. These two antigens displayed reversible, linear adsorption behavior in the pH range 5–9, with maximal adsorption observed at the lowest pH studied. The addition of acetate buffer ions had little effect on adsorption, while the presence of phosphate decreased adsorption for R32NS181 and NS181V20 by 25 and 40% respectively. The adsorptive behavior of these two antigens with the negatively charged adjuvant, aluminum phosphate, was markedly decreased. The converse situation was observed with the R32tet32 antigen, whose pI is estimated to be 12.8. There was minimal interaction of this antigen with aluminum hydroxide gel except in the presence of phosphate counter ions and significant, nonreversible adsorption with aluminum phosphate gel. Enhanced adsorption of R32tet32 to aluminum hydroxide gel in the presence of phosphate is suggested to be the result of a covalent bond between a surface aluminum and a phosphate anion that modifies the surface charge of the aluminum hydroxide gel. These results indicate that the role of complementary surface charges, both for the ionization state of the protein and for the aluminum adjuvants, is the key in optimizing conditions for significant antigen-adjuvant interactions.     

Mutations in human breast cancer: an overview

Studies of mammary tumorigenesis in mice infected with the mouse mammary tumor virus and in certain strains of transgenic mice with an activated oncogene have provided strong evidence that multiple mutations contribute to the initiation and progression of malignancies in the breast. The increasing availability of recombinant DNA probes that detect various proto-oncogenes, growth factor genes, and growth factor receptor genes, as well as restriction fragment length polymorphisms in the human population, have made possible a molecular approach for the identification of frequently occurring mutations in primary human breast tumor DNA. The aim of studies using this molecular approach has been to investigate whether specific mutations are highly associated with various clinical parameters, including disease prognosis. Eight mutations have been identified, including amplification of c-myc, c-erbB2, and int-2, as well as loss of heterozygosity on five chromosomes (1q, 3p, 11p, 13q, and 17p). Loss of heterozygosity is thought to unmask recessive mutations of tumor-suppressor genes. In some studies, amplification of either c-myc, c-erbB2, or int-2 has been found to have a significant association with high risk of relapse or poor survival. The current status of these mutations as potentially useful prognostic indicators for the management of the disease is controversial and points to the need for further research in this area.