心电图短P-R间期观测研究

目的：探讨和鉴别心电图短Ｐ－Ｒ间期的产生原因，为临床诊断、治疗提供依据。方法：检测１１５例受检者的常规导联心电图（ＲＬＥＣＧ）、头胸导联心电图（ＨＣＥＣＧ）、食管导联心电图（ＥＬＥＣＧ），对其中５５例临床可疑心律失常和ＲＬＥＣＧ示短Ｐ－Ｒ间期者行食管心房调搏电生理检查。结果：①Ｐ波出现率和振幅均值比较ＥＬＥＣＧ＞ＨＣＥＣＧ＞ＲＬＥＣＧ（Ｐ＜０．０１），出现率分别为１００％、９５％、９１％。②ＨＣＥＣＧＰ－Ｒ段均值（Ｐ＜０．０１）及变异系数＜ＲＬＥＣＧ。③ＲＬＥＣＧ波幅低、图形多变是产生心电图短Ｐ－Ｒ间期的主要原因。结论：作为无创伤性检查方法，ＨＣＥＣＧ和ＥＬＥＣＧ可以对短Ｐ－Ｒ间期者进行初步筛选，而经食管心房调搏能检测ＥＣＧ短Ｐ－Ｒ间期的电生理特性，对鉴别诊断有肯定价值。     

Relation Between Cycle Length, Volume, and Pressure in Type I Atrial Flutter

Assuming that type I atrial flutter is a macroreentrant circuit, its cycle length should vary with the atrial dimensions. In order to test this hypothesis, flutter cycle length was measured while inducing atrial volume and pressure changes by postural and pharmacological means in seven patients undergoing a therapeutic programmed stimulation for type 1 atrial flutter conversion. Right atrial volume was estimated from B-mode echocardiography data. Basal values were compared with those obtained during inspiration, expiration, Valsalva maneuver, negative tilt (head down), and positive tilt (head up) with 0.8–1.6 mg p.o. nitroglycerin. The right atrial size increased slightly from 17.8 to 18.3 cm² (P = 0.04) during the pressure load induced by negative tilt (+ 3 mmHg), with a corresponding lengthening of the flutter cycle length from 228 to 233 msec (P = 0.02). Similarly, pressure unloading of -2 mmHg by positive tilting and nitrates was accompanied by a decrease in right atrial size to 16.6 cm² (P = 0.04), with a corresponding decrease in cycle length from 228 to 219 msec (P = 0.03). Respiratory maneuver yielded similar results with an inspiratory cycle lengthening, expiratory shortening, and further shortening during Valsalva maneuver. These experiments demonstrate a direct relation between cycle length and atrial volume in human type I atrial flutter. They underline the importance of the right heart preload and atrial size for the electrophysiological characteristics of type I atrial flutter. Beside its fundamental interest, this finding is important for the understanding of the mechanism of maintenance and therapeutic responses of this common arrhythmia.     

POTASSIUM ACCELERATES URINARY SODIUM EXCRETION DURING SALT LOADING WITHOUT STIMULATING ATRIAL NATRIURETIC POLYPEPTIDE SECRETION

1. Effects of potassium (K) supplementation (100 mEq/day) on urinary sodium (Na) excretion and on the secretion of atrial natriuretic polypeptide (ANP) during salt loading (350 mEq/day) were studied in 12 healthy salt-resistant normotensives under strictly controlled metabolic ward conditions. 2. Urinary volume and Na excretion on the first day of the high salt period (HSP) were significantly greater in the K-supplemented group (KG) than in the control group (CG). 3. There was a significant gain in bodyweight after salt loading in both groups, with a significantly greater gain in CG on the second day of HSP. Haematocrit decreased significantly during salt loading in both groups, the degree of which was significantly greater in CG. 4. Plasma norepinephrine decreased significantly during salt loading in both groups, the degree of which was significantly less in KG than in CG. A significant increase in plasma ANP was observed in CG on and after the second day of HSP, while a significant increase in plasma ANP was observed on the fifth day of HSP in KG. 5. These findings indicate that K supplementation accelerates diuresis and natriuresis, resulting in moderate suppression of volume expansion induced by salt loading and that this accelerated diuresis and natriuresis is not a result of the action of ANP.     

藻酸钙凝胶-成骨细胞-骨粉构建工程化骨修复兔颅骨缺损的实验研究

目的探讨藻酸钙凝胶、成骨细胞、骨粉复合构建的可塑形组织工程骨修补兔颅骨缺损后的形态学变化和成骨效果.方法28只日本大耳白兔,随机分为A(n=20)、B(n=8)两组,手术在兔颅顶骨矢状缝两侧分别各建立一个直径1cm的圆形全层缺损,用两种方法藻酸钙凝胶、成骨细胞、骨粉和藻酸钙凝胶、骨粉分别构建组成可塑形的组织工程骨复合材料,分别填补修复A组兔颅骨左右两侧的缺损,B组为空白对照组,通过大体、组织学、X线观察材料的形态变化、成骨情况,并对X线片和组织学切片进行评分.结果材料植入后,局部未见红肿、积液、渗出等异常反应.①藻酸钙凝胶-成骨细胞-骨粉组修补后12周颅骨缺损基本被硬性组织所修复,镜下见修复材料大多被骨组织替代,骨粉基本被吸收,有块状凝胶残留其中,组织学评分为(5.50±1.00).X线片见兔颅骨缺损处有高密度骨痂影存在,布满整个缺损区,X线片评分为(3.25±0.95).②藻酸钙凝胶-骨粉组修补后12周部分颅骨缺损被硬性组织所修复,镜下见修复材料部分转变成骨组织,骨粉基本被吸收,有凝胶残留其中,组织学评分为(3.25±1.50).X线片见兔颅骨缺损处有高密度骨痂影存在,主要分布在缺损区的边缘部位,X线片评分(2.25±0.25).③空白对照组骨缺损主要被膜样纤维组织修复,在紧邻骨缺损边缘处有硬性组织形成,镜下见修复组织边缘有骨组织存在,中央大部为膜状致密纤维组织,组织学评分为(1.50±0.50),X线片仅见靠近骨缺损边缘的部位存在致密骨痂影,X线片评分为(1.00±0.57).结论藻酸钙凝胶、成骨细胞、骨粉构建的可塑形组织工程骨可根据颅骨缺损的形态进行塑形填补,在体内有良好的成骨能力,可达到对兔颅骨缺损的骨性修复,但部分藻酸盐凝胶吸收缓慢,手术后12周仍不能满意吸收.     

颌面赝复材料研究进展

综述了目前口腔颌面赝复材料种类、性能要求及各种颌面赝复材料的组成、性能和应用过程,探讨了各种颌面赝复材料的优势及不足,指出目前临床应用的颌面赝复材料以硅橡胶类为主,其中又以中温硫化硅橡胶和室温硫化硅橡胶综合性能较好,应用最为广泛。     

吻合指固有神经背侧支的邻指皮瓣修复手指远端掌侧软组织缺损

目的探讨采用吻合指固有神经背侧支的邻指皮瓣修复手指远端掌侧软组织缺损的疗效. 方法 1996年10月～2004年6月,25例(32指)伴肌腱或骨组织外露的手指远端掌侧软组织缺损患者,其中男18例,女7例,年龄13～45岁.切割伤6例,冲压伤8例,机器绞伤11例.损伤部位:拇指2例,食指8例,中指5例,环指3例,小指2例,食、中指2例,中、环指2例,食、中、环、小指1例.缺损范围:1.5 cm×1.0 cm～4.0 cm×2.1 cm.损伤至就诊时间30 min～48 h.急诊行清创,采用带蒂邻指皮瓣修复,术中同时将指固有神经的背侧支与指神经残端吻合重建皮瓣感觉,术后3周断蒂.供区中厚皮片游离植皮. 结果术后皮瓣及供区均成活,创面Ⅰ期愈合.获随访6～26个月,手指指腹饱满,色泽正常,感觉恢复,两点辨别觉为5～8 mm,均无功能障碍. 结论采用吻合指固有神经背侧支邻指皮瓣修复手指远端掌侧软组织缺损不仅能修复缺损皮肤,且能重建皮瓣感觉,术式操作简便.     

邻近非主干血管蒂皮瓣移位修复足跟部皮肤缺损

目的探讨足跟部皮肤缺损皮瓣修复的优化选择及临床效果. 方法 2000年2月～2004年4月,应用4种邻近非主干血管蒂皮瓣移位修复足跟部皮肤缺损30例,其中男19例,女11例,年龄8～65岁.致伤原因:车轮绞伤19例,重物压伤5例,电锯伤3例,骨髓炎2例,足跟部鳞状细胞癌1例.皮肤缺损6.0 cm×5.5 cm～16.5 cm×11.0 cm者14例,均合并足后跟或足底皮肤缺损,采用腓肠神经营养血管远端蒂皮瓣及隐神经营养血管远端蒂皮瓣修复,皮瓣切取范围6.0 cm×5.0 cm～18.0 cm×12.0 cm;皮肤缺损2.5 cm×2.0 cm～5.5 cm×4.5 cm者16例,采用足外侧皮瓣及足底内侧皮瓣修复,皮瓣切取范围4.0 cm×3.0 cm～8.0 cm×7.0 cm.供区采用全厚或中厚皮片移植覆盖. 结果术后皮瓣均成活.获随访6～12个月,皮瓣外观良好,无破溃,2例出现胼胝.皮瓣痛觉或触觉部分或完全恢复,两点辨别觉恢复至1.0～3.2 cm.供区外观恢复良好. 结论采用邻近非主干血管蒂皮瓣移位修复足跟部皮肤缺损,具有切取简便、损伤少、不影响患肢血供、可选择性高和可操作性强等优点,是足跟皮肤缺损修复的一种较好选择.     

Fibrous metaphyseal defects — determination of their origin and natural history using a radiomorphological study

The radiomorphological appearance of fibrous metaphyseal defects (FMDs) is demonstrated by long-term follow-up studies. A characteristic radiomorphological course rather than a typical single appearance can be established. These findings correlate well with the duration of these tumor-like lesions; therefore, the radiological findings allow conclusions to be made about the age of a fibrous metaphyseal defect. In addition, the characteristic locations of FMDs will be explained in respect of their origins at insertions of tendons and ligaments.     

心脏病患者血浆心钠素浓度初探

本文报道了采用放射免疫分析法检测的136例健康人和95例心脏病患者血浆心钠素含量的结果。健康人血浆心钠素含量为460．86±23．68ng／L，男女之间，年龄之间无明显差异。心脏病患者的血浆心钠素浓度均高于健康人，心脏病患者心功能越差，血浆心钠素浓度越高，其中以肺心病组变化最为明显。     

筋膜皮瓣治疗小腿顽固溃疡9例报告

本文报道应用小腿后侧筋膜皮瓣治疗9例胫前区顽固性溃疡的经验,一期治愈者8例,二次皮瓣转移治愈者1例。随诊6个月至2年,未见溃疡复发。