小儿重症肺炎淋巴细胞凋亡的临床意义

目的　探讨小儿重症肺炎淋巴细胞凋亡的临床意义。方法　对 2 2例重症肺炎患儿分别在第 1天、第 5天采用流式细胞术检测其外周血中淋巴细胞早期凋亡率、晚期凋亡及坏死率 ,并与 2 1例普通肺炎患儿进行比较。结果　第 1次 ,重症肺炎患儿外周血淋巴细胞早期凋亡率为 (19 76±13 87) % ,晚期凋亡及坏死率为 (6 16± 6 6 0 ) % ,与普通肺炎组 [(11 14± 3 1) %和 (2 4 6± 2 72 ) % ]比较 ,差异均具显著性意义 (t=2 78,P <0 0 1;t=2 ,2 1,P <0 0 5 ) ;第 2次 ,重症肺炎患儿外周血淋巴细胞早期凋亡率为 (16 5 6± 13 6 ) % ,晚期凋亡及坏死率为 (2 79± 2 81) % ,与普通肺炎组 [(6 6± 1 9) %和 (1 4 3± 1 5 8) % ]比较 ,差异均具显著性意义 (t=3 32 ,P <0 0 1;t=2 0 3,P <0 0 5 )。结论　外周血淋巴细胞凋亡在重症肺炎患儿疾病的演变过程中可能起着一定的作用 ,提示对淋巴细胞凋亡的调控可能有助于疾病的恢复。     

幽门螺杆菌相关性胃炎胃粘膜上皮细胞的增殖凋亡及凋亡相关基因Fas的研究

目的　研究幽门螺杆菌 (HP)感染儿童胃粘膜上皮细胞的增殖、凋亡及凋亡相关基因Fas的变化 ,对幽门螺杆菌的致病机制进行探讨。方法　采用免疫组织化学和Tunel法检测 17例HP阳性小儿慢性胃炎和 19例HP阴性的小儿慢性胃炎胃粘膜上皮细胞增殖、凋亡和凋亡相关基因Fas的变化。结果　HP阳性组的胃粘膜上皮细胞增殖指数为 (9 0 2± 3 82 ) % ,凋亡指数为 (8 46±1 82 ) % ,Fas指数为 (31 2 9± 12 ) % ,HP阴性组胃粘膜上皮细胞增殖指数为 (3 41± 1 33) % ,凋亡指数为 (2 73± 0 85 ) % ,Fas指数为 (11 6 8± 9) %。三者在HP阳性组与HP阴性组之间差异有显著意义 ,与年龄性别无关 ;胃粘膜上皮细胞增殖指数在轻度胃炎为 (3 94± 3 5 1) % ,中度胃炎为 (6 5 3± 4) % ,重度胃炎为 (13 6 5± 7) % ,三者间差异有显著意义 ;凋亡指数在轻度胃炎为 (3 0 8± 1 0 5 ) % ,中度胃炎为 (5 82± 3) % ,重度胃炎为 (17 81± 2 6 3) % ,三者间亦差异有显著意义。细胞的增殖和凋亡在炎症程度间差异有显著意义。结论　HP促进胃粘膜上皮细胞的增殖和凋亡 ;Fas的表达在HP阳性组明显增加 ,提示Fas的过度表达可能是小儿HP相关性胃炎胃上皮细胞凋亡增加的原因之一。     

延期手术对新生儿重症膈疝疗效的初步探讨

目的　探讨延期手术对新生儿重症膈疝的疗效和意义。方法　本文回顾 1985～ 2 0 0 3年复旦大学附属儿科医院收治的 2 0例重症新生儿先天性膈疝 (CDH)病例 ,其中 11例患儿进行了延期手术 ,最短 12h ,最长 5 4h ,平均2 5 3h ,3例围术期吸入一氧化氮 (NO)。以急诊手术 9例作为对照 ,对一般情况、围术期动脉血气、超声心动图结果、手术疗效和预后随访进行对照分析。结果　急诊手术组入院pH(7 19± 0 0 3)、PCO2 (18 4 3± 1 0 5 )kPa ,术后pH(7 2 4± 0 0 4 )、PCO2 (9 0 4± 4 6 6 )kPa ,术后平均呼吸机使用时间 4 0 7d ,其中 4例存活 ,5例死亡 ;延期手术组入院pH((7 19± 0 5 9)、PCO2 (6 89± 1 12 )kPa ,术前pH(7 37± 0 15 )、PCO2 (5 4 8± 2 2 6 )kPa ,都较入院有明显改善 ,术后pH(7 4 5± 0 0 2 )、PCO2 (5 0 5± 2 13)kPa ,恢复较急诊组理想 ,患者平均术后呼吸机使用时间 4 5 7d。延期组中患儿 10例存活 ,1例因术后严重肺炎无法脱离呼吸机 ,家属放弃治疗。结论　延期手术以及NO吸入等措施对于改善围手术期管理和稳定术前血流动力学指标及内环境有一定的作用 ,对降低新生儿先天性膈疝的病死率有积极的意义。     

腹腔镜改良Soave巨结肠根治术后排便功能的随访

目的　评价腹腔镜改良Soave根治术后患儿排便控制情况。方法　自 1999年 5月～2 0 0 1年 9月 ,对 6 4例年龄为 10d～ 1岁的先天性巨结肠患儿行腹腔镜改良Soave巨结肠根治术。术后定期随访患儿 ,平均随访时间为 (2 3.8± 1)个月 ,对患儿大便控制能力、便秘及结肠炎的发生率进行评价。结果　获访 4 3例患儿。大便控制评分正常 (10分 ) 2 2例 ,好 (6～ 9分 ) 18例 ,欠佳 (1～ 5分 )3例 ;1例患儿 (2 .3% )有持续便秘 ;5例 (11.6 % )患儿曾出现结肠炎。结论　应用腹腔镜改良Soave巨结肠根治术治疗新生儿及小婴儿先天性巨结肠 ,术后可获得良好的排便控制功能。     

大鼠隐睾、隐睾下降固定对生殖细胞发育、凋亡影响的实验研究

目的　探讨大鼠隐睾、隐睾下降固定对生殖细胞发育、凋亡的影响。方法　 6 8支SD雄性大鼠 ,分为三组 :隐睾组 (5 2 ) ;隐睾下降固定组 (8)及对照组 (8)。于日龄 2 2d时复制单侧隐睾模型 ,一部分于单侧隐睾模型术后 14d复制隐睾下降固定模型。采用生物素 dUTP/酶标亲和素测定法检测睾丸生殖细胞凋亡。结果　 1.单侧隐睾模型术后第 13d内隐睾侧睾丸生殖细胞凋亡指数随时间的延长而增加 ;从术后第 4天起 ,与自身对侧正常睾丸 (4.8± 0 .9) %相比 ,隐睾侧睾丸 (11.2±3.6 ) %发生凋亡的生殖细胞数显著增加 (P <0 .0 1)。 2 .与隐睾组 (47.5± 8.6 ) %相比 ,隐睾下降固定组 (6 .2± 1.8) %发生凋亡的生殖细胞数显著降低 (P <0 .0 1)。结论　 1.大鼠隐睾模型建立术后13d内隐睾侧睾丸生殖细胞凋亡指数随时间的延长而增加 ;2 .在日龄 36d时隐睾下降固定能使大鼠隐睾恢复正常的生精功能 ;3.隐睾患儿应及早施行睾丸下降固定术 ,可以恢复其生育能力。     

婴幼儿体外循环心内直视手术315例临床分析

目的总结婴幼儿体外循环(CPB)心内直视手术的治疗经验。方法总结2002年1月至2005年11月315例婴幼儿先心手术患儿资料。其中男187例,女128例;年龄4d～3岁,其中<6个月23例,～1岁41例,>1岁251例;体重2.5～18.5kg,平均(10.30±2.65)kg。非紫绀型心脏病254例,紫绀型心脏病61例。所有病例在体外循环下行根治性手术314例,姑息性手术1例。结果术后死亡11例,死亡率3.49%;术后出现并发症46例(14.60%)。结论婴幼儿先天性心脏病必须早诊断、早手术治疗;提高手术成功率的关键是把握好手术指征和时机,选择适当手术方式,加强术中心肌保护和术后治疗。     

小儿先天性心脏病重度肺高压手术后远期疗效

目的　评估小儿先天性心脏病 (先心病 )重度肺高压手术治疗的远期疗效 ,分析影响其远期疗效的因素。方法　系统观察 1 981～ 2 0 0 1年 ,1 1 2例 (其中男 68例 ,女 44例 ,年龄 2个月～ 1 6岁 )左向右分流先心病伴重度肺高压手术治疗后的转归。病种包括房间隔缺损 (ASD) 3例 ,室间隔缺损 (VSD) 81例 ,室间隔缺损伴动脉导管未闭 (PDA) 1 2例 ,室间隔缺损伴房间隔缺损 1例 ,室间隔缺损伴房间隔缺损伴动脉导管未闭 1例 ,动脉导管未闭 1 3例 ,主肺动脉隔缺损 1例。肺动脉收缩压与体动脉收缩压之比 (Pp/Ps)≥0 .75者列为观察对象。年龄 2个月～ 1 6岁。结果　住院死亡 3例 ,术后半年、2年、3年各死亡 1例 ,手术生存率 97.32 % ,1年生存率 96 .43 % ,5年生存率 94.64 %。生存者纽约心脏病学会 (NYHA)心功能分级 :Ⅰ、Ⅱ级 (优良组 ) 99例 (93 .4 % ) ,Ⅲ级 (差组 ) 7例 (6 .60 % )。死亡病例均为术后持续肺高压。生存病例 ,优良组与差组术时年龄比较 ,(3 .39± 2 .94)岁对 (6 .57±3 .51 )岁 (P <0 .0 5)。肺血管阻力比较 ,(6 .78± 4 .0 4 )U/M2 对 (1 2 .2 6± 4 .1 7)U/M2 (P <0 .0 1 )。结论　小儿左向右分流先心病伴重度肺高压术后远期疗效与术时年龄 ,肺血管阻力有关 ,婴幼儿期手术预后较理想。     

小儿重度肾积水术后肾功能的评价

目的　观察重度肾积水患儿术后肾脏功能的恢复情况及影响因素。方法　利用ECT检查 ,测定 5 0例患儿术后患肾功能 ,2 0例患儿手术前后患肾功能 ,并分析影响患肾功能恢复的因素。结果　 5 0例患儿术后患肾功能平均为 (4 0 .6 2± 10 .0 9) % ,其中 32 %的患儿术后患肾功能接近正常 ,分肾功能达 45 %以上。 2 0例患儿手术前后患肾功能分别为 (2 0 .45± 9.5 0 ) %和 (37.10± 9.16 ) % ,患肾功能提高 (16 .73± 11.5 1) % (P =0 .0 0 0 5 )。术中测量的患肾实质厚度和术后患肾功能的恢复呈负相关 (r =- 0 .79,P =0 .0 0 4) ;随访时间和术后患肾功能的恢复呈正相关 (r =0 .76 ,P =0 .0 14) ;手术时年龄和患肾功能恢复无显著相关性 (r =- 0 .5 7,P =0 .12 )。肾外型肾积水术后患肾功能恢复明显高于肾内型肾积水 (P =0 .0 44 )。结论　重度肾积水患儿术后患肾功能可获得很好的恢复 ,部分患儿患肾功能恢复接近正常 ,应保留患肾。肾实质薄者 ,随访时间长者及肾外型肾积水患肾功能恢复明显。     

7公斤以下患儿心脏手术中体外循环管理的新探讨

目的　通过总结并对比 2年内 7kg以下患儿体外循环中和术后的管理资料 ,探讨低体重患儿体外循环管理新经验。方法　从 1999年 5月～ 2 0 0 0年 5月对 86例 7kg以下先天性心脏病(先心病 )患儿中随机选取 40例作为传统组 ,平均年龄 (8.0± 1.9)个月 ,平均体重 (6 .7± 0 .9)kg ,同时从 2 0 0 0年 5月～ 2 0 0 1年 5月的 117例 7kg以下先心病患儿中随机选取 40例作为改良组 ,平均年龄(7.3± 0 .8)个月 ,平均体重 (6 .1± 1.3)kg ,通过对比两组患儿体外循环预充资料、改良超滤应用和术后一般情况 ,总结小体重患儿体外循环管理经验。结果　改良组患儿体外循环中的预充总量 (4 10 .5± 2 7.3)ml明显少于传统组 (76 7.8± 46 .2 )ml(P <0 .0 1) ,其中库血预充量 (2 17.5± 34 .0 )ml明显少于传统组 (4 5 8.6± 6 7.1)ml(P <0 .0 1) ,白蛋白预充量 (5 8.5± 12 .1)ml和晶体预充量 (112 .5± 2 0 .6 )ml少于传统组 (112 .7± 2 4.6 )ml,(2 80 .5± 5 6 .2 )ml(P <0 .0 5 ) ;改良组 40例患儿中有 37例应用改良超滤装置 (MUF) ,而传统组未应用MUF ;从术后ICU的恢复情况看 ,改良组患儿的气管带管时间和在ICU停留时间明显少于传统组 (P <0 .0 1)。结论　对于 7kg以下的低体重先心病患儿施行体外循环时 ,应用预充少的     

婴幼儿呼吸道合胞病毒感染特点及支气管肺炎细胞免疫等指标的变化

目的　了解近年来苏州地区婴幼儿呼吸道合胞病毒 (RSV)的感染特点及支气管肺炎 (支肺 )细胞免疫等指标改变情况。方法　应用直接免疫荧光法 (DFA)对 2 6 72份下呼吸道感染婴幼儿鼻咽分泌物行RSV抗原检测 ;用间接免疫荧光法 (IFA)对 2 0例RSV支肺婴幼儿血液进行细胞免疫指标测定 ;用酶联免疫法(ELISA)测其血清IFN r、IL 4及IgE。设同龄健康对照组。结果　婴幼儿RSV感染率以冬春季最高(49.13% ) ,夏秋季最低 (4.6 0 % ) (χ2 =4 11.2 2　P <0 .0 0 1) ;1岁以内组 (不包括新生儿 )婴幼儿RSV感染率高于 1～ 2岁组 (χ2 =12 .34　P <0 .0 0 5 ) ,1～ 2岁组高于 2～ 3岁组 (χ2 =8.0 8　P <0 .0 0 5 ) ;男性婴幼儿RSV感染率高于女性 (χ2 =6 .6 7　P <0 .0 0 5 ) ;RSV支肺婴幼儿存在较低的CD3+ (% )、CD4 + (% )、CD8+ (% )水平 (5 3.17± 5 .4 8、34.4 8± 3.6 7、2 2 .5 4± 2 .93,P均 <0 .0 0 1)及较高HLA DR+ (% )水平 (2 3.70± 3.97,P <0 .0 0 5 ) ;血清IFN r(kU/L)、IL 4 (kU/L)水平则分别低于、高于健康组 (0 .38± 0 .2 0　P <0 .0 0 5 ;5 2 .18± 2 9.99,P <0 .0 5 ) ,而血清IgE(kU/L)差异无显著性 (P >0 .0 5 )。结论　婴幼儿RSV感染具有明显地区性和季节周期性 ;年龄越小其RSV感染率越高 ;RSV支肺     

Allergic factors associated with the development of asthma and the influence of cetirizine in a double-blind, randomised, placebo-controlled trial: First results of ETA®

There is a common progression known as the allergic march from atopic dermatitis to allergic asthma. Cetirizine has several antiallergic properties that suggest a potential effect on the development of airway inflammation and asthma in infants with atopic dermatitis. Methods. Over a two year period, 817 infants aged one to two years who suffered from atopic dermatitis and with a history of atopic disease in a parent or sibling were included in the ETAC^® (Early Treatment of the Atopic Child) trial, a multi-country, double-blind, randomised, placebo-controlled trial. The infants were treated for 18 months with either cetirizine (0.25mg/ kg b.i.d.) or placebo. The number of infants who developed asthma was compared between the two groups. Clinical and biological assessments including analysis of total and specific IgE antibodies were performed. Results. In the placebo group, the relative risk (RR) for developing asthma was elevated in patients with a raised level of total IgE (≥ 30 kU/I) or specific IgE (≥ 0.35 kUA/I) for grass pollen, house dust mite or cat dander (RR between 1.4 and 1.7). Compared to placebo, cetirizine significantly reduced the incidence of asthma for patients sensitised to grass pollen (RR = 0.5) or to house dust mite (RR = 0.6). However, in the population that included all infants with normal and elevated total or specific IgE (intention-to-treat - ITT), there was no difference between the numbers of infants developing asthma while receiving cetirizine or placebo. The adverse events profile was similar in the two treatment groups. Discussion. Raised total IgE level and raised specific IgE levels to grass pollen, house dust mite or cat dander were predictive of subsequent asthma. Cetirizine halved the number of patients developing asthma in the subgroups sensitised to grass pollen or house dust mite (i.e. 20% of the study population). In view of the proven safety of the drug, we propose this treatment as a primary pharmacological intervention strategy to prevent the development of asthma in specifically sensitised infants with atopic dermatitis.     

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孤独症谱系障碍(autistic-spectrum disorders,ASDs)近年来患病率逐年攀升至1%左右,其症状往往伴随终生,成为严重威胁儿童健康和发展的神经发育性疾患;注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)是儿童期最常见的精神障碍,国内报道患病率为4.13%～5.83%,其症状可延续至青少年期,甚至到成年期[1]。这两类精神障碍在成年期的临床表现、共患病、治疗策略和预后与儿童期有哪些不同呢?本文通过回顾相     

Infiltrations of Epstein-Barr virus-carrying cells in granular lymphocyte-proliferative disorders corresponding to chronic active Epstein-Barr virus infection

A 21-year-old man with granular lymphocyte-proliferative disorders (GLPD) associated with chronic active Epstein-Barr virus (EBV) infection is described. Chromosomal analyses revealed several clonal abnormalities and two of them were mainly repetitious. High copy numbers of monoclonal EBV genome were also detected in the proliferative large granular lymphocytes (LGLs), indicating the monoclonal expansion of EBV-infected LGLs. The patient had an indolent course for several years, and there was no evidence of infiltrations of his bone marrow until the end stage. At autopsy, microscopic studies revealed marked infiltrations of LGL in the liver and spleen, and the infiltrating cells were NK-cell immunophenotype. The infiltrated LGLs showed latency I.     

LUTEINIZING HORMONE RECEPTOR MUTATIONS IN DISORDERS OF SEXUAL DEVELOPMENT AND CANCER

Human male sexual development is regulated by chorionic gonadotropin (CG) and luteinizing hormone (LH). Aberrant sexual development caused by both activating and inactivating mutations of the human luteinizing hormone receptor (LHR) have been described. All known activating mutations of the LHR are missense mutations caused by single base substitution. The most common activating mutation is the replacement of Asp-578 by Gly due to the substitution of A by G at nucleotide position 1733. All activating mutations are present in exon 11 which encodes the transmembrane domain of the receptor. Constitutive activity of the LHR causes LH releasing hormone-independent precocious puberty in boys and the autosomal dominant disorder familial male-limited precocious puberty (FMPP). Both germline and somatic activating mutations of the LHR have been found in patients with testicular tumors. Activating mutations have no effect on females. The molecular genetics of the inactivating mutations of the LHR are more variable and include single base substitution, partial gene deletion, and insertion. These mutations are not localized and are present in both the extracellular and transmembrane domain of the receptor. Inactivation of the LHR gives rise to the autosomal recessive disorder Leydig cell hypoplasia (LCH) and male hypogonadism or male pseudohermaphroditism. Severity of the clinical phenotype in LCH patients correlates with the amount of residual activity of the mutated receptor. Females are less affected by inactivating mutation of the LHR. Symptoms caused by homozygous inactivating mutation of the LHR include polycystic ovaries and primary amenorrhea.     

EXCITING NEW TREATMENT APPROACHES FOR PATHYPHYSIOLOGIC MECHANISMS OF SICKLE CELL DISEASE

During the past several decades, our understanding of the complex pathophysiology of vasoocclusion associated with sickle cell disease has improved greatly. Interaction of genes, hemoglobin molecules, red cell membrane and metabolic changes, cell-cell interactions and cell-plasma interactions, red cell adhesion to vascular endothelium, activation of coagulation, and vascular reactivity play a role in vaso occlusion. Penicillin prophylaxis of pneumococcal infections and appropriate use of blood transfusions and other supportive measures improved survival of sickle cell patients. Hydroxyurea made a major impact on sickle cell therapy when it was shown to decrease acute painful episodes, acute chest syndrome, and the need for blood transfusion in adults. Significant experience in the use of hydroxyurea has been accumulated in older children. The benefits and risks of hydroxyurea for younger children and long-term risks in all patients will be evaluated in future investigations. Other promising therapies include butyrate compounds, clotrimazole, magnesium supplementation, poloxamer 188, antiadhesion agents, anticoagulant approaches, and nitric oxide. Hemopoietic transplantation remains the only curative therapy. However, several transgenic mouse models are available for studies of gene therapy or other treatment approaches on biochemical, cellular, and pathologic effects of mutant genes.     

Bibliometric data: a disaster for many non-American biomedical journals

Bibliometric data published by the Institute of Scientific Information in Philadelphia (ISI), and which was previously discussed in Acta Paediatrica , has increasingly been used despite all the relevant and severe criticism that has been raised against this method of evaluating individual research results and grading scientific journals. It is obvious that the present trend regarding the use of bibliometric data as a basis for priorities and funding of research and for the promotion of individual scientists favours American-oriented research projects at the expense of those that are based on concepts of predominantly European relevance.

Conclusion: For the future of non-American research, it is important that no single super-power, i.e. the USA, should dominate scientific priorities. The condition for efficient European competition is that European Centres with high levels of competence for creative research and training of scientists from all over the world are established. In addition, it is important that the results of European research are published in prestigious European journals, as was the situation before World War II.     

Personality profiles and heart rate variability (vagal tone) in children with recurrent abdominal pain

The aim of the study was to explore psychological factors and autonomic activity in children with recurrent abdominal pain and to compare them with those in a control group of healthy children. The Personality Inventory for Children was used for assessment of developmental, emotional and psychosocial factors in 25 children with recurrent abdominal pain (age, 7-15 y). Parasympathetic and sympathetic functions in these children and in 23 healthy control subjects (age, 7-13 y) were also investigated, non-invasively using a computerized polygraph. Vagal tone (parasympathetic function) was indexed by calculation of respiratory sinus arrhythmia in beats/min. Skin conductance (sympathetic function) was recorded by the constant current method. On the Personality Inventory for Children, 16 patients had high scores on somatic concern. Several patients had scores in the clinical range for depression, withdrawal and anxiety, but the mean scores for these personality profile scales were well within the normal range of healthy children. Interestingly, there was a spike on the L (Lie)-scale for most of the patients and 15 patients had scores above or close to the clinical cut-off value. As compared with the scores in healthy children, vagal tone and sympathetic tone were normal. Conclusion: Many children with recurrent abdominal pain have scores in the clinical range for depression, withdrawal, anxiety and L-scale indicating coping problems, denial and a trend towards somatic concern that may contribute to the evolution of abdominal pain. Autonomic nerve activity was not disturbed in these children.     

Understanding infant formula

The World Health organisation recommends breast feeding infants for the first six months of life. When this breast feeding does not occur either through parental choice or medical need, infant formulas will be required. There is a bewildering array of formulas on the UK market for many different requirements. When faced with an unsettled infant many parents (and healthcare professionals) will experiment with the infant formula available and then attend the paediatric clinic looking for help and advice. It is therefore essential that paediatricians understand what milks are available and what the key differences between different products are. This review attempts to provide a simple guide through many of the formulations currently available in the UK; and offers advice for the dietary management of the child with extra calorie requirements, infants with cow's milk protein allergy, gastro oesophageal reflux disease, apparent unresolved hunger and infantile colic. Whatever the underlying condition, there is likely to be an infant formula that is suitable in this generation of ever expanding formulations.     

Overcoming surfactant inhibition with polymers

Inhibition of the function of pulmonary surfactant in the alveolar space is an important element of the pathophysiology of many lung diseases, including meconium aspiration syndrome, pneumonia and acute respiratory distress syndrome. The known mechanisms by which surfactant dysfunction occurs are (a) competitive inhibition of phospholipid entry into the surface monolayer (e.g. by plasma proteins), and (b) infiltration and destabilization of the surface film by extraneous lipids (e.g. meconium-derived free fatty acids). Recent data suggest that addition of non-ionic polymers such as dextran and polyethylene glycol to surfactant mixtures may significantly improve resistance to inhibition. Polymers have been found to neutralize the effects of several different inhibitors, and can produce near-complete restoration of surfactant function. The anti-inhibitory properties of polymers, and their possible role as an adjunct to surfactant therapy, deserve further exploration.