年轻人冠心病危险因素分布及聚集状况

目的　观察年轻人中冠心病危险因素的分布及聚集状况 ,为早期年轻人防治冠心病提供依据。方法　选择年轻冠心病患者 (经冠状动脉造影证实 ,年龄≤ 40岁 ) 1 78例作为疾病组 ,并以年龄匹配的冠状动脉造影正常的年轻人 70例作为对照组 ,分析了传统危险因素 (高血压、高血糖、高血脂、肥胖、吸烟史、家族史 )和新危险因素同型半胱氨酸 (HCY)、脂蛋白 (a)、小而密低密度脂蛋白、C反应蛋白 (CRP)在两组间的变化特点及聚集情况。结果　 (1 )在传统的危险因素中 ,疾病组的甘油三酯(TG)和胆固醇 (TC)水平、吸烟和家族史的比率明显高于对照组 (P <0 0 5) ;在新的危险因素中 ,疾病组的血浆HCY(2 1 66± 1 8 2 2 ) μmol L和CRP(5 78± 6 90 )mg L比对照组的血浆HCY(1 4 94± 8 97)μmol L和CRP(2 87± 2 0 0 )mg L明显增高 (P <0 0 1 ) ,其他危险因素在两组间比较差异无显著性。(2 )疾病组与对照组比较 ,有危险因素者明显增多 (P <0 0 5) ,2种以上新危险因素聚集增加 ,3种新危险因素聚集比较差异有显著性 (P <0 0 5) ,传统危险因素聚集性比较差异无显著性。 (3)logistic回归显示吸烟 (OR值为 2 4,95 %CI:1 31 5～ 4 2 75)、TG(OR值为 1 8,95 %CI:1 2 1 5～ 2 541 )、HCY(OR值为 1 9,95 %CI:1 0 60     

冠心病患者C反应蛋白水平及其1059G/C基因多态性的研究

目的　研究中国汉族人群中血清高敏C反应蛋白 (CRP)水平及其 10 5 9G C基因多态性与冠状动脉造影证实的冠心病之间的关系。方法　采用免疫比浊法测定 35 6例冠状动脉造影患者的高敏CRP水平 ,同时应用聚合酶链反应 -限制性片段长度多态性 (PCR RFLP)核苷酸分型技术检测CRP的 10 5 9G C基因多态性 ,结合冠状动脉造影结果进行分析。结果　冠心病组的自然对数转换CRP(lnCRP)水平显著高于对照组 (P <0 0 5 ) ,以年龄、性别、吸烟、高血压、体重指数和lnCRP水平为自变量的Logistic回归分析显示 ,lnCRP水平 (OR =1 4 4,P <0 0 1)和体重指数 (OR =1 0 1,P <0 0 5 )与冠心病的危险性独立相关。 10 5 9G C基因多态性等位基因和基因型的分布频率符合Hardy Weinberg平衡 ( χ2 =0 2 97,P >0 0 5 )。两组的 10 5 9G C基因型和等位基因的分布趋势相同 ,差异无显著性 (P>0 0 5 )。C等位基因携带者的lnCRP水平低于GG基因型 [( 0 5 3± 1 0 1)比 ( 0 88± 0 99)lnmg L ;P =0 0 2 4],而冠状动脉病变程度不受 10 5 9G C基因多态性的影响 ( χ2 =1 374,P >0 0 5 )。结论　血清高敏CRP水平升高可能是中国汉族人冠心病发生的独立危险因素 ;CRP的水平可能受其 10 5 9G C基因多态性的影响。     

C-反应蛋白与动脉粥样硬化形成有关

为探讨C -反应蛋白与动脉粥样硬化及其它心血管病危险因素的关系 ,以高分辨率B型超声法测定91例受检者的颈动脉内膜 -中膜厚度 ,作为动脉粥样硬化的指标 ;以生物化学方法测定血清C -反应蛋白、血脂水平和血浆凝血纤溶活性。结果发现 ,颈动脉内膜 -中膜厚度≥ 0 .8mm组的血清C -反应蛋白水平高于内膜 -中膜厚度 <0 .8mm组 (4 .4± 4.3mg L比 2 .7± 1.3mg L) ,但差异的显著性无统计学意义 (P =0 .0 71)。 6例血清C -反应蛋白水平≥ 8.0mg L者颈动脉内膜 -中膜厚度明显高于其余 85例血清C -反应蛋白 <8.0mg L者 (1.0 33± 0 .2 94mm比 0 .812± 0 .2 2 2mm ,P <0 .0 5 )。多因素逐步回归分析显示血清C -反应蛋白水平与血清甘油三酯水平 (β=0 .5 33,P =0 .0 0 2 ) ,及血浆凝血因子VII (β =0 .40 6 ,P =0 .0 17)和纤溶酶原激活物抑制剂 - 1(β =0 .312 ,P =0 .0 5 )活性呈显著正相关。因此 ,C -反应蛋白作为某些炎症的反应蛋白 ,与颈动脉内膜 -中膜厚度及其某些心血管病危险因素有关 ,提示炎症因素可能在动脉粥样硬化发病中起作用。     

冠心病及其高危患者血管功能无创性检测的临床意义

目的 :探讨冠心病和具有冠心病危险因素患者的血管内皮和平滑肌功能无创性检测的临床意义。方法 :采用高分辨超声技术 ,检测 90例健康成人 (正常对照组 )、110例有冠心病危险因素者 (危险因素组 )和 71例冠心病患者 (冠心病组 )在反应性充血时及含服硝酸甘油后的肱动脉内径变化。结果 :危险因素组和冠心病组血流介导的肱动脉舒张 (FMD)均明显低于正常对照组 [(4 .79± 3.93) %和 (2 .4 4± 2 .94 ) %比 (8.76± 4 .33) % ,均P <0 .0 1];冠心病组硝酸甘油引起的肱动脉舒张 (NID)明显低于正常对照组 [(16 .5 8± 6 .2 6 ) %比 (2 3.6 2±8.5 5 ) % ,P <0 .0 1],但危险因素组的NID与正常对照组无统计学意义 [(2 0 .5 0± 7.30 ) %比 (2 3.6 2± 8.5 5 ) % ,P >0 .0 5 ]。多元逐步回归分析显示 :FMD与年龄、肱动脉基线内径和收缩压呈负相关 ,与高密度脂蛋白胆固醇呈正相关 ;而NID与肱动脉基线内径呈负相关 ,与FMD呈正相关。结论 :血管内皮功能失调是动脉粥样硬化临床前的早期表现 ,而血管平滑肌功能损害常提示患者已存在明显动脉粥样硬化病变     

C-反应蛋白是急性冠脉综合征的一种危险因子

目的　研究急性冠脉综合征 (包括不稳定性心绞痛、急性心肌梗死和心源性猝死 )患者血清C 反应蛋白(CRP)浓度水平并与对照组 (即非急性冠脉综合征 ,包括稳定性心绞痛、陈旧性心肌梗死和正常体检人群 )比较 ,探讨CRP是否为急性冠脉综合征的一种危险因子。方法　用速率散射比浊法测定急性冠脉综合征患者和对照组血清CRP浓度 ,同时检测冠心病的常见危险因子并与CRP一起作Lo gistic回归分析。结果　①急性冠脉综合征患者血清CRP浓度 [18 5 0mg/L± 2 3 98mg/L (SE 2 5 1,n =91) ]显著高于对照组 [3 89mg/L± 7 14mg/L (SE 0 5 1,n =194 ) ](P <0 0 1)。②急性心肌梗死急性期患者CRP浓度 (18 6 5mg/L± 2 4 12mg/L)和不稳定性心绞痛CRP浓度 (17 95mg/L±2 4 10mg/L)显著高于正常对照组 (P <0 0 1)、稳定性心绞痛CRP浓度 (3 94± 7 5 0mg/L) (P <0 0 1)、急性心肌梗死患者恢复期 (5 93mg/L± 13 0 7mg/L) (P <0 0 1)和陈旧性心肌梗死患者 (4 5 7mg/L± 8 2 7mg/L) (P <0 0 1) ;稳定性心绞痛患者、急性心肌梗死患者恢复期和陈旧性心肌梗死患者之间CRP浓度无差别 (P >0 0 5 )并与正常人群比较无显著性差别 (P >0 0 5 )。③每增加CRP 5mg/L ,急性冠脉综合征发生危险增加到近 2倍 (用Logistic回归 ,OR     

C-反应蛋白与冠心病患者冠状动脉斑块形态的关系

目的 :检测冠状动脉 (冠脉 )造影显示Ⅱ型斑块的患者血清C 反应蛋白 (CRP)水平 ,从临床的角度探讨斑块破裂发生的原因。方法 :112例接受了冠脉造影的冠心病患者纳入本研究。对其冠脉造影的斑块形态进行分型。根据斑块形态 ,患者分为两组 ,即Ⅰ型病变 (表面光滑 )组 (n =45 )及Ⅱ型病变 (表面不规则 )组 (n =6 7)。所有患者于冠脉造影前采血进行血清CRP、全血心脏肌钙蛋白T(cTnT)、血清肌酸激酶 (CK)及肌酸激酶MB同工酶 (CK MB)的测定。结果 :Ⅱ型病变组平均血清CRP水平显著高于Ⅰ型病变组 ( 4 32± 0 35mg/L对 2 18± 0 2 2mg/L ,P <0 0 0 0 1)。而两组患者之间 ,年龄、性别、4个主要冠心病危险因素的合并率、全血cTnT、血清CK及CK MB水平均无显著差别 (P>0 0 5 )。结论 :冠脉造影显示斑块破裂的冠心病患者血清CRP水平明显升高。从临床的角度提示 ,炎症反应是导致斑块破裂的原因 ,进而也是导致急性冠脉综合征 (ACS)发生的重要始动因素之一     

C-反应蛋白、内皮功能变化与急性冠状动脉综合征相关性研究

目的　探讨 C-反应蛋白及肱动脉流量介导的血管舒张在急性冠状动脉综合征中的变化及其相关性。方法　急性冠状动脉综合征 (ACS)组 5 1例 ,其中急性心肌梗死 (AMI) 15例 ,不稳定性心绞痛 (U AP) 36例 ;选择 2 2例冠状动脉造影除外冠心病的患者为对照组。用速率散射比浊法测血清 C-反应蛋白 (CRP) ,用高分辨率超声测肱动脉反应性充血引起的流量介导血管扩张 (FMD)与硝酸甘油介导的血管扩张 (NTG)。结果　 ACS组 CRP高于对照组(0 .94± 1.45 mg/ dl vs0 .2 7± 0 .2 1mg/ dl,P<0 .0 5 ) ,AMI亚组 CRP明显高于 UAP亚组与对照组 (1.6 4± 1.82mg/ dl vs0 .6 5± 1.17m g/ dl、 0 .2 7± 0 .2 1m g/ dl,P<0 .0 5 ) ,UAP亚组高于对照组 (0 .6 5± 1.82 m g/ dl vs0 .2 7±0 .2 1m g/ dl,P>0 .0 5 )。ACS组的 FMD明显低于对照组 (4 .6 1± 2 .2 1mm vs9.2 3± 3.45 mm,P<0 .0 5 ) ,而 NTG与对照组比较则无差别。经 logisitic回归分析 ,CRP的风险比值 (OR)值大于 1,是 ACS的危险因素 ,FMD的 OR值小于 1,是 ACS的保护因素。经前进法观察 CRP与 FMD在急性冠脉综合征中的作用是相互独立的。结论　急性冠状动脉综合征患者 C-反应蛋白升高 ,内皮功能受损 ,二者是 ACS发生的独立危险因素     

脑利钠肽和C-反应蛋白在急性冠状动脉综合征介入治疗患者的预后价值

目的探讨急性冠状动脉综合征(ACS)行经皮冠状动脉介入治疗术(PCI)患者血浆脑利钠肽(BNP)和C-反应蛋白(CRP)水平与临床预后的关系。方法连续性入选189例行PCI治疗的ACS患者。测定症状发作平均(34·2±16·3)h的血浆BNP和CRP水平,随访患者住院期间,30天,3个月病死率及主要心脏不良事件(MACE)(心原性死亡,再次心肌梗死,再发心绞痛,继发心衰和再入院的复合终点)发生率。结果189例ACS患者根据血浆BNP水平分为四组:≤100ng/L组;>100~≤300ng/L组;>300~≤600ng/L组和>600ng/L组。随血浆BNP水平的升高,各组病死率及MACE发生率呈明显递增趋势。3个月时,各组病死率分别为0%、1·4%、7·7%、48·3%;MACE发生率分别为7·9%、17·1%、57·7%、79·3%。在多变量的logistic回归分析中,BNP独立于年龄、性别、家族史、吸烟、高脂血症、高血压、糖尿病及LVEF等危险因素,预测30天(r=0·8515,P<0·01)和3个月(r=0·9201,P<0·01)病死率及30天(r=0·7066,P<0·01)和3个月(r=0·7090,P<0·01)MACE发生率。其中141例患者根据血浆CRP水平分为三组:≤8·0mg/L组;>8·0~≤32·0mg/L组;>32·0mg/L组。随着血浆CRP水平的升高,各组死亡事件及MACE发生率亦呈明显递增趋势。3个月时,病死率分别为2·7%、7·7%、28·6%;MACE发生率分别为28·4%、41·0%、60·7%。在多变量的logistic回归分析中,CRP独立于年龄等其他冠心病危险因素,预测30天(r=0·5882,P=0·0044)和3个月(r=0·5235,P=0·0038)病死率。经年龄因素校正后,CRP独立于性别等其他冠心病危险因素,预测30天(r=0·2705,P=0·0380)和3个月(r=0·2290,P=0·0429)MACE发生率。当将CRP、BNP和年龄等其他冠心病危险因素放入同一模型预测ACS的预后时,血浆CRP水平失去了预测效能,而血浆BNP水平升高独立于各因素预测30天和3个月病死率及MACE发生率。结论BNP和CRP能够很好地对ACS患者行PCI治疗后进行危险分层,预测近期病死率和MACE发生率。BNP可能是较CRP更好的预测ACS患者近期临床预后的指标。     

冠心病患者血清褪黑素的变化

目的 :研究冠心病患者血清褪黑素 (Melatonin ,MLT)变化 ,了解MLT与冠心病的可能关系 ,观察β 受体阻滞剂对冠心病患者MLT分泌的影响。方法 :用放射免疫分析法测定对照组 2 0例、冠状动脉造影证实冠状动脉高度狭窄的不稳定型心绞痛 (UA)患者 30例 (其中 14例服用 β 受体阻滞剂 )及急性心肌梗死 (AMI)患者33例 (其中 16例服用 β 受体阻滞剂 ) ,清晨 5 :30～ 6 :0 0测血清MLT。分析 3组间血清MLT水平的差异。 结果 :UA组及AMI组血清MLT水平分别为 (2 4 .4 5± 2 0 .80 )、(31.2 2± 2 5 .80 )ng/L ,均明显低于对照组 [(4 7.0 3±2 5 .6 2 )ng/L],差异有统计学意义 (均 P <0 .0 1)。服用与未服用 β 受体阻滞剂的冠心病患者间血清MLT水平差异无统计学意义 (P >0 .0 5 )。结论 :冠心病患者体内血清MLT显著降低 ,β 受体阻滞剂不影响冠心病患者MLT的分泌     

血清脂蛋白-a水平与急性主动脉夹层关系探讨

目的　探讨脂蛋白-a水平与主动脉夹层的关系。方法　选取诊断明确的2 7例急性主动脉夹层患者和同期年龄、性别构成相近的急性心肌梗塞患者6 0例、健康人群5 0例,检测分析他们的血脂蛋白-a[LP(a) ]、C -反应蛋白(CRP)及白细胞(WBC)计数水平,并观察其中8例主动脉夹层患者发病后2 4小时、72小时、5天LP(a)、CRP、白细胞计数的动态变化。结果　(1)主动脉夹层组、急性心肌梗塞对照组、健康对照组血清平均LP(a)浓度分别为32 7. 35±89 .2 3mg .L-1、2 6 1. 35±77 .5 4mg .L-1、79 .6 9±2 1. 6 3mg .L-1,三组间差别有统计学意义(P <0 .0 5 ) ;(2 )主动脉夹层组和急性心肌梗塞对照组患者血平均CRP水平分别为12 . 12±6 .15mg .dL-1和10 . 31±8 .33mg .dL-1,白细胞计数分别为11 .0 6±4. 2×10 .9 L-1、10 . 38±5 . 6×10 .9 L-1,均高于健康对照组(P <0 . 0 1) ;但前两组患者间CRP、白细胞计数比较无统计学意义(P >0. 0 5 ) ;(3)主动脉夹层发病后72小时内LP(a)、CRP水平和白细胞水平均呈持续性升高,入院后第5天CRP、白细胞水平明显下降,LP(a)仍处于较高水平。结论　急性主动脉夹层患者血清LP(a)水平明显升高,可能与其促炎症反应有关。     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.