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111.
Stochastic models for geriatric in-patient behaviour 总被引:1,自引:0,他引:1
Departments of geriatric medicine engage in two distinct formsof clinical activity: acute/rehabilitative and long-stay care.These are organizationally distinct and have very differentresource needs. Current hospital planning models, however, assumethat patients all move through the system at the same rate,thereby ignoring this effect of inherent heterogeneity in patientbehaviour. The present paper describes the movement of patientsthrough geriatric hospitals by a two-stage continuous-time Markovmodel, where the stages represent acute/rehabilitative and long-staypatients respectively. Patients are initially admitted to thefirst stage, from which they may depart from the system, bydeath or discharge, or move into the second stage, from whichthey eventually depart by death or discharge (unlikely). Admissionsare modelled in two ways: either as replacements for departuresor as a Poisson stream. Expressions for the distribution andmovement of numbers of patients are derived and evaluated fordata from a number of hospitals. Such an approach has the advantage,over previous crude models, of taking into account differenttypes of patients and introducing variability, thus making itpossible to extract variances as well as means of numbers ofgeriatric patients requiring hospital care. 相似文献
112.
作者曾经体外实验证明,均聚寡脱氧胞嘧啶核苷酸片段(dC14)有抗病毒活性,现继续研究其在体内的作用。不给dC14的对照组小鼠,接种腹水瘤细胞后:100%发病和死亡,潜伏期为6d,存活期11d;给每只小鼠dC14 1.3~3.2 mg,发病率和死亡率降低至20%,疾病潜伏期和存活期推迟。在未经dC14处理的种瘤细胞和淋巴组织与经处理的淋巴组织中,多聚酶链反应(PCR)法都检测到病毒核酸,而正常小鼠中则无此种病毒核酸顺序。研究结果提示,dC14对小鼠SRS腹水瘤的发病和生长有抑制作用。此种抑制作用可能是通过抑制病毒基因的表达来实现的。 相似文献
113.
本文应用聚合酶链反应(PCR)对125例乙型肝炎病毒患者血清进行了HBV-DNA检测,根据其检测结果与乙型肝炎病毒的其它复制标志物HBcAg(检测125例)、HBeAg(检测115例)、PreS_2Ag(检测92例)、PHSA-R(检测114例)、Anti—HBclgM(检测118例)进行比较。HBV-DNA阳性血清中HBcAg、HBeAg、PreS_2Ag、PHSA-R、Anti-HBcIgM的检出率分别为83.75%(67/80)、62.34%(48/77)、61.02%(39/59)、74.03%(57/77)、72.97%(54/74)。经统计学处理,显示五项复制标志物与HBV-DNA的相关关系应是:HBcAg>PHSA-R>Anti-HB-cIgM>HBeAg>PreS_2Ag。在HBV-DNA(PCR)阳性血清中,HBcAg的检出率为最高。提示在除HBV-DNA(PCR)外,上述五项标志物中,HBcAg可能是HBV-DBA复制的最佳指标。HBeAg在HBV复制过程中的地位仍有待今后进一步探讨。 相似文献
114.
We describe the pathological findings in two fatal cases of neonatal infection with herpes simplex virus. One had an encephalitis caused by herpes simplex virus type 2 (HSV-2); the other had a disseminated infection with herpes simplex virus type 1 (HSV-1). Confirmation of the diagnosis was obtained by use of the polymerase chain reaction to amplify viral DNA from paraffin sections of autopsy tissues. By using primers which amplify fragments of the HSV-1 thymidine kinase gene and HSV-2 glycoprotein gene respectively it was possible to discriminate between infection with HSV-1 and HSV-2. In contrast, immunohistochemistry and in situ hybridization using commercially available reagents did not distinguish between HSV-1 and HSV-2 infection. However, immunohistochemistry and in situ hybridization are probably more reliable than the polymerase chain reaction for assessment of the distribution of virus in different tissues. 相似文献
115.
载脂蛋白B信号肽序列多态性及其与冠心病的关联 总被引:4,自引:0,他引:4
应用聚合链反应(PCR)对103例冠心病人及100名正常人载脂蛋白B(apoB)基因5'端信号肽序列的多态性研究结果表明:(1)中国人信号肽序列插入/缺失(Ins/Del)多态性频率分布与国外不同种族间有差异。少见Del等位基因相对频率为0.259,高于南亚人,但低于法国高加索人。(2)冠心病组与正常对照组间等位基因相对组间等位基因相对频率分布差异无显著意义。(3)冠心病组内具Del等位基因者血浆 相似文献
116.
Vasoactive intestinal peptide (VIP), the structurally homologous pituitary adenylate cyclase-activating peptide (PACAP) and the pituitary hormone, prolactin (PRL) enhance rapid eye movement sleep (REMS). VIP and PACAP are both inducers of PRL gene expression and release in the pituitary gland. Little is known about PRL regulation in the brain although it is hypothesized that the REMS-promoting activity of i.c.v. administered VIP may be mediated via the activation of cerebral PRL. To test whether VIP or PACAP in fact increase intracerebral mRNA, the peptides (VIP: 30 or 300 pmol; PACAP: 220 pmol) were injected i.c.v. into rats at dark onset. 1 h later, cDNA was synthesized from purified hypothalamic mRNA. Standardized amounts were analysed for PRL using the polymerase chain reaction followed by Southern blotting and hybridization. Compared with β-actin mRNA levels, both VIP and PACAP increased PRL mRNA levels in a dose-dependent fashion though VIP was more effective on a molar basis. The previously reported alternatively spliced PRL mRNA (lacking exon 4) was not detected. The data support the hypothesis that the REMS-promoting activity of central VIP and PACAP might be mediated by cerebral PRL. 相似文献
117.
以四川地区1例无症状携带丁型肝炎病毒(HDV)和乙型肝炎病毒(HBV)患者的外周血为标本,采用逆转录-PCR技术,获得了HDV全基因组的cDNA克隆(HDVSZ93株),全长1684bp。与世界其他七个地区株相比,其核酸同源性为81.8%~95.4%;丁肝病毒抗原蛋白编码区核酸同源性为88.9%~96.1%,氨基酸同源性为86,4%~93.0%。另从1例慢性重型肝炎患者血清内克隆了丁肝病毒抗原蛋白(HDAg)编码基因(HDV-SZ92株),与SZ93株相比,亦存在若干变异。对这些不同地区、不同病情HDV株变异的可能意义进行了讨论。 相似文献
118.
The crystal structure of a tripeptide, tryptophanyl-glycyl-glycine dihydrate (C15H18N4O4·2H2O, molecular weight = 354) has been determined. The crystals are orthorhombic, space group P212121 with a= 7.875 (1) A,b= 9.009(1), c= 24.307(1) and Z = 4. The final R-index is 0.058 for 1488 reflections ((sin θ/λ≤ 0.6 A?1) with I < 2σ(I). The molecule exists as a zwitterion, with terminal NH+3 and COO? groups. The peptide units are trans and nearly perpendicular to the plane of the carboxyl group. The backbone torsion angles are: ψ1= 132.7°, ω1= 174.2°, φ2 88.2°, ψ= 8.6°, ω2 - 179.8°, φ= - 85.2°, ψ31, = - 178.1°, ψ32 5.0°. For the sidechain of tryptophan, χ1= - 171.6°, χ2 101.0°. 相似文献
119.
The dipeptide, L-prolyl-L-isoleucine monohydrate (C11 H20N2O3· H2O, molecular weight 246.3) crystallizes in the monoclinic space group P21, with a = 6.601(3)Å, b = 5.413(3) Å, c = 19.128(6) Å, β= 98.1(1)°, Z = 2, Do = 1.20g·cm-3 and Dc = 1.208g·cm-3. The structure was solved by MULTAN–80 and refined to a final R-factor of 0.081 for 594 reflections measured on a Enraf Nonius CAD-4 diffractometer. The peptide linkage exists in the trans conformation. The pyrrolidine ring is disordered with two alternate envelope conformations for the Cγ atom. The values of the sidechain torsion angles are: χ11=– 63.6(17)°, χ12= 171.1(16)° and χ2=– 59.6(21)° for isoleucine (C-terminal). The crystal structure is stabilized by a three-dimensional network of N—H ? O, O—H ? O and C—H ? O hydrogen bonds. The dipeptide exists in the extended Conformation. 相似文献
120.
Segments of nicotinic acetylcholine receptor α sub-unit genes have been isolated from a panel of insect species by polymerase chain reaction, using degenerate oligonucleotide primers designed to recognize conserved regions of the Drosophila melanogaster ALS and SAO genes. The amplified segments encode elements of typical a-subunits anticipated to play roles in ligand binding and ion channel formation. Each is also clearly either ALS or SAD-like. The predicted protein sequences display extremely high levels of conservation (over 85% for each subtype) even though derived from very distantly related insect species. 相似文献