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1.
The literature concerning the asymmetry clasping hands is reviewed based on 192 studies. This paper describes the incidence, sex differences, age differences and genetical problems including twinning. The incidence of left hand clasping ranges from 30% to 75% (mean 43%). The review confirms the so-called east-west-gradient and there is a predominance of the left type in Europe. Age and sex differences are only small. There is only a small relationship between hand clasping and handedness. 18 authors examined hand clasping in families and 4 in twins. The family data suggest that hand clasping may be under genetic control, yet it is clear that no simple genetic model for the inheritance can be applied. Both monozygotic and dizygotic twins show a low concordance and the R-R, R-L and L-L pairs in monozygotic and dizygotic twins are in binomial distribution.  相似文献   

2.
An increased twinning rate has been observed in the near relatives (sibs, parents, and aunts and uncles) of probands with neural tube defects (NTDs) occurring at the level of the 11th thoracic vertebra and above (upper NTDs). The twin rate was more than double that of the near relatives of probands with lower NTDs and of those of probands with Mendelian disorders (the controls). The excess twinning was same sex and can therefore consist of either MZ or same-sex DZ twins. Furthermore, upper-NTD families with twins had a higher NTD-sibling occurrence rate than did families without twins. These findings, if corroborated, may imply an etiology common to twinning and NTDs and can perhaps be applied in counseling NTD families.  相似文献   

3.
The dermatoglyphic (genetical) distance coefficients have been estimated within monozygotic and dizygotic twin pairs, between left and right sides of the same individual and between normal subjects and 21-trisomics. All the coefficients have been based, in turn, on frequencies of fingertip, palmar and sole pattern elements, separately and for all characters combined. Quantitative variables (pattern intensities) have also been used for independent evaluation of the C2H distance coefficient in monozygotic and dizygotic twins, and in 21-trisomics as compared with normal individuals. The values of a distance have then been considered in relation to the degree of genetical likeness between the compared items as well as to the relative contribution of each pattern combination to the overall value of a distance. Some limitations in the interpretation of the results, connected mainly with statistical procedures, are also discussed.  相似文献   

4.
A biometrical genetical analysis of IgG, IgM, and IgA levels in 134 sets of twins is reported. High heritabilities, around .8, are found for all three immunoglobulin levels, and possible reasons for lower heritabilities found in family studies are discussed. There is evidence for genetical dominance tending to decrease IgM and IgA levels, but there is no evidence for the importance of family environment although the presence of dominance may make its detection difficult. The causes of covariation in the three measurements are unclear in males but in females appear to be mainly environmental in correlations with IgA and equally genetical and environmental in the IgG-IgM correlation.  相似文献   

5.
When a phenotype is determined by a specific gene combination of several loci, it is called an emergenic trait. Such a trait, although genetically controlled, does not usually run in families, since the specific gene combination can hardly be preserved in the process of reproduction. The present paper suggests a concrete genetical model to account for the phenomenon that there is little resemblance between siblings and parent-child pairs with respect to this trait. The genetical model is multiple homozygosis for all loci involved in the gene configuration. The properties of such a trait in a random mating population for all families, as well as for the segregating families only, are investigated. Some of the difficulties in estimating the genetical parameters on the basis of empirical data are also discussed.  相似文献   

6.
Aesthetic units of the face have been previously described. The lip itself may be divided into smaller topographic subunits. The lateral subunit is bordered by philtrum column, nostril sill, alar base, and nasolabial crease, while the medial topographic subunit is one-half the philtrum. When a large part of a subunit has been lost, replacing the entire subunit rather than simply patching the defect often gives a superior result. The only tissue suitable for the aesthetic restoration of moderate-sized defects of the upper lip is lower lip. An exact pattern is outlined and an Abbé flap is taken from the midline of the lower lip and transferred in two stages. Like tissue is replaced in kind, border scars are positioned aesthetically, and the orbicularis sphincter is reconstituted with an intact symmetrical commissure, muscular modiolus, and upper and lower lip symmetry. Spontaneous reinnervation by appropriate segmental facial branches occurs within 1 year. Four patients are presented.  相似文献   

7.
Significantly larger variation between sibships within families of male MZ twins than between sibships within families of female MZ twins, indicative of maternal influences, was found for 10 of 41 dermatoglyphic fingertip variables. Of these, five were thumb-related with the effect primarily on the thumb radial and ridge count (larger of radial and ulnar count). These same variables were previously found to have unequal variances in MZ twins of known placental type, and the results indicate maternal influences in singletons as well as twins for these variables. Although the total ridge count (TRC), previously shown to differ in MZ twins of known placental type (paralleling the thumb radial and ridge counts) did not reach significance, the trend indicated that the observed thumb changes may be reflected in the TRC as well. Little finger pattern type and ulnar counts also showed less variability in families of female MZ twins, but the interpretation is complicated by the concomitant differences in mean squares within-sibships for these little finger variables.  相似文献   

8.
台闽苣苔(苦苣苔科)花部器官的形态发生   总被引:1,自引:0,他引:1  
在扫描电镜下对台闽苣苔 (T .oldhamii (Hemsl.)Solereder)进行了花部器官形态发生的观察 ,为探索该类群的个体发育、类群间的系统发育关系和进化趋势提供依据。研究发现该属植物萼片、花冠和雄蕊发生式样均为五数花类型 ,它们各自来源于花原基上分化出来的萼片原基、花冠原基和雄蕊原基 ;花冠与雄蕊的两侧对称性与花冠上唇生长稍快和退化雄蕊原基发育迟滞相关 ;萼片原基的发生和发育的顺序是不一致的 :萼片原基发生的式样为近轴中原基—远轴 2原基— 2侧原基 ,发育式样则为近轴中萼片— 2侧萼片—远轴 2萼片 ,花蕾时为镊合状排列。花冠裂片原基的发生和发育式样是一致的 ,即远轴中裂原基 (下唇中裂片 )—远轴 2侧裂原基 (下唇 2侧裂片 )—近轴 2裂原基 (上唇 2裂片 )。花蕾期卷迭式为覆瓦状排列 ,从外向内 :下唇中裂片—下唇 2侧裂片—上唇 2裂片或下唇 2侧裂片—上唇 2裂片—下唇中裂片。雄蕊原基与花冠裂片原基互生 ,前方雄蕊原基在发生上稍迟于后方雄蕊原基 ,后者与退化雄蕊原基几乎同时发生 ,但较小 ,并与近轴心皮 (或柱头上唇 )对生。将该属与玄参科 (Scrophulari aceae)的地黄属 (Rehmannia)、苦苣苔科 (Gesneriaceae)的异叶苣苔属 (Whytockia)和尖舌苣苔属 (Rhynchoglossum)的花部器官比较发现  相似文献   

9.
Radical paring of the cleft edge during a primary cleft operation or repeated secondary surgeries can result in tightness of the upper lip. The degree of the resulting side-to-side tension can vary, from mild cases for which improvement is sought through realignment of the misplaced oral sphincter muscle in secondary revision, to severe cases for which the possibility of a lip switch flap must be considered. When the lip tightness accompanies more than three-quarters loss of the Cupid's bow, an Abbé flap is an alternative. However, the lip switch flap is far from ideal, in both artistic and functional perspectives, and should be avoided if at all possible in mild to moderate degrees of lip tightness. This study presents a method of correcting horizontal cleft upper lip tightness, especially of the vermilion. The method involves local transfer of an inferiorly based rectangular flap from the relatively redundant upper two-thirds to the lower one-third of the upper lip and vermilion. Primary indications for the technique include vermilion tightness with half to three-quarters loss of Cupid's bow. The method has the advantage of supplementing the horizontal lip dimension on the cleft side and restoring a natural Cupid's bow, thereby repositioning the shifted philtral column and adding fullness to the lower one-third of the upper lip. Incorporation of the upper lip scar in the rectangular flap removes ugly scars and spares the lower lip from surgical violation. The orbicularis sphincter function, as seen in facial animation, was well regained. Twenty unilateral and three bilateral cases with a maximal follow-up period of 4.5 years are presented.  相似文献   

10.

Introduction

Squamous cell carcinoma is one of the most common malignant tumors of the skin and oral mucosa. However, squamous cell carcinoma involving near total upper and lower lip and oral commissure is rarely seen in the English literature. Simultaneous reconstruction of the upper and lower lips has been inconclusive and presents a challenge to the surgeon. We report such a case and outline our simultaneous reconstruction with local flaps. To the best of our knowledge this has never been reported.

Case presentation

A 73-year-old Thai woman presented with a large rapidly growing squamous cell carcinoma involving the upper lip, lower lip, left oral commissure and left cheek. En bloc resection of upper lip, lower lip, left oral commissure and buccal region was performed. Left radical neck dissection and right modified neck dissection were performed. Reconstruction of the upper lip with a left nasolabial-cheek cervicofacial rotational-advancement flap and right cheek advancement with perialar crescent flap was performed. The lower lip was reconstructed with bilateral labiomental advancement flaps.

Conclusions

Squamous cell carcinoma can grow rapidly and spread along the orbicularis oris muscle and across the oral commissure to the opposite lip. In advanced cancer, multimodal treatment is necessary. No gold standard in the reconstruction of both upper and lower lips has been established. We report the case of an advanced squamous cell carcinoma involving both the upper lip, lower lip, left oral commissure and buccal area and simultaneous reconstruction with local flap coverage that, to the best of our knowledge, has never been reported.  相似文献   

11.
Congenital double lip: a review of seven cases   总被引:1,自引:0,他引:1  
Congenital double-lip deformity is an infrequent developmental abnormality affecting the lips, more commonly the upper lip. We report seven cases of double lip, all in males, of which six were in the upper lip and one in the lower lip. It was quite interesting to observe that in the upper lip, the buccal portion of the double lip appeared on either side with a midline constriction; in the lower lip, it was prominent in the midline without any central constriction. Surgical excision under regional nerve block anesthesia gives good results. The embryology, clinical appearances, and histopathology are discussed with a review of the literature.  相似文献   

12.
Summary The problem of the regional specification of snout vibrissae and dorsal pelage hairs has been analysed in mouse embryos. Reconstituted homo-and heterotopic skin explants, consisting of epidermis and dermis from both regions, were cultured on the chorioallantoic membrane of the chick embryo.Recombinants of 12.5-day upper lip dermis and 12.5-day dorsal epidermis developed a small number of large vibrissal type follicles arranged in a recognizable rectangular vibrissal pattern. The reverse combinations of 12.5- or 14.5-day dorsal dermis and 11- to 12.5-day upper lip epidermis formed a single population of numerous and small follicles arranged in a typical pelage hair pattern (trio groups) or gave rise to a mixed population of follicles with both whiskers and pelage hairs.It is concluded that the dermis is responsible for the regional specification of the cutaneous appendages and their distribution pattern. However, at the time it was isolated, the upper lip epidermis already possesses the information for the morphogenesis of vibrissae, but remains malleable and responsive to the dermal influence.This work was supported in part by DGRST and CNRS  相似文献   

13.
Different kinds of articulators, such as the upper and lower lips, jaw, and tongue, are precisely coordinated in speech production. Based on a perturbation study of the production of a fricative consonant using the upper and lower lips, it has been suggested that increasing the stiffness in the muscle linkage between the upper lip and jaw is beneficial for maintaining the constriction area between the lips (Gomi et al. 2002). This hypothesis is crucial for examining the mechanism of speech motor control, that is, whether mechanical impedance is controlled for the speech motor coordination. To test this hypothesis, in the current study we performed a dynamical simulation of lip compensatory movements based on a muscle linkage model and then evaluated the performance of compensatory movements. The temporal pattern of stiffness of muscle linkage was obtained from the electromyogram (EMG) of the orbicularis oris superior (OOS) muscle by using the temporal transformation (second-order dynamics with time delay) from EMG to stiffness, whose parameters were experimentally determined. The dynamical simulation using stiffness estimated from empirical EMG successfully reproduced the temporal profile of the upper lip compensatory articulations. Moreover, the estimated stiffness variation significantly contributed to reproduce a functional modulation of the compensatory response. This result supports the idea that the mechanical impedance highly contributes to organizing coordination among the lips and jaw. The motor command would be programmed not only to generate movement in each articulator but also to regulate mechanical impedance among articulators for robust coordination of speech motor control.  相似文献   

14.
Large, full-thickness lip defects after head and neck surgery continue to be a challenge for reconstructive surgeons. The reconstructive aims are to restore the oral lining, the external cheek, oral competence, and function (i.e., articulation, speech, and mastication). The authors' refinement of the composite radial forearm-palmaris longus free flap technique meets these criteria and allows a functional reconstruction of extensive lip and cheek defects in one stage. A composite radial forearm flap including the palmaris longus tendon was designed. The skin flap for the reconstruction of the intraoral lining and the skin defect was folded over the palmaris longus tendon. Both ends of the vascularized tendon were laid through the bilateral modiolus and anchored with adequate tension to the intact orbicularis muscle of the upper lip. This procedure was used in 12 patients. Six patients had cancer of the lower lip, five patients had a buccal cancer involving the lip, and one patient had a primary gum cancer that extended to the lower lip. Total to near-total resection (more than 80 percent) of the lower lip was indicated in six patients. In two other patients, the cancer ablation included more than 80 percent of the lower lip and up to 40 percent of the upper lip. A radial forearm palmaris longus free flap was used in all cases for reconstruction of the defect. Free flap survival was 100 percent. At the time of final evaluation, which was 1 year after the operation, all patients had good oral continence at rest (static suspension) and had achieved sufficient oral competence when eating. Ten patients were able to resume a regular diet, and two patients could eat a soft diet. All patients regained normal or near-normal speech and had an acceptable appearance. The described refinement of the composite radial palmaris longus free flap technique allows the reconstruction of the lower lip with a functioning oral sphincter; the technique can be recommended for patients who need large lower lip resection. It provides functional recovery of the reconstructed lower lip synchronizing with the remaining upper lip.  相似文献   

15.
Solifugae possess an evertable, adhesive pedipalpal organ (suctorial organ) at the tip of the distal tarsus of each pedipalp that is unique among arachnids. When inverted inside the pedipalp, the suctorial organ is covered with two cuticular lips, a dorsal upper lip and a ventral lower lip, but it can be protruded rapidly in order to facilitate grasping prey or climbing on bushes or even climbing on smooth surfaces due to its remarkable adhesive properties. In this study, the suctorial organs of different species from old world families Galeodidae and Karschiidae and new world families Ammotrechidae and Eremobatidae were investigated by means of light microscopy, scanning and transmission electron microscopy. In all representatives, the suctorial organ is formed by an evertable, cuticular pad with a complex internal stabilizing structure. The procuticle of this pad consists of a lattice-like basal plate and numerous stalked structures connected to this basal plate. The shafts of the stalked structures are regularly organized and ramify apically. The surface of the suctorial organ is constituted of a very thin epicuticle overlaying the ramifying apices forming ridges and furrows on the ventral side of the suctorial organ.  相似文献   

16.
Measurements were taken from 18 patients operated on for cleft lip and palate, aged 19 to 27 years, and 162 control subjects matched for sex, age, and ethnic group. Nine soft-tissue landmarks on the lips were digitized by a three-dimensional electromagnetic instrument. From the landmarks, several linear distances (mouth width, philtrum width, vermilion height of upper and lower lip, total vermilion height, total lip height), the interlabial angle, and some areas (vermilion of upper lip, vermilion of lower lip, total vermilion) and volumes (upper lip volume, lower lip volume, total lip volume) were calculated. Patient and reference data were compared by t tests and Watson-Williams tests. In the men, significant differences (p < 0.05) were found in width of the philtrum, height and area of the vermilion part of the upper lip, and total vermilion height and area (all larger in male patients than in controls). In the women, significant differences were found in the height and area of the vermilion part of the upper lip (larger in female patients than in controls), and in the height and area of the vermilion part of the lower lip (smaller in patients than in controls). In both sexes, the interlabial angle was smaller than in the reference population. In conclusion, the upper lip of adult patients operated on for cleft lip and palate differed from that of healthy controls of the same age, sex, and ethnic group. Surgical correction of cleft lip and palate failed to provide a completely normal appearance. The analysis pointed out those parts of the lips and mouth (in particular, the vermilion part of the upper lip) that differed the most from the norm. The method may be used to indicate to the surgeon and patient where additional procedures might be performed to approximate the morphologic characteristics of a reference population.  相似文献   

17.
Free flaps are generally the preferred method for reconstructing large defects of the midface, orbit, and maxilla that include the lip and oral commissure; commissuroplasty is traditionally performed at a second stage. Functional results of the oral sphincter using this reconstructive approach are, however, limited. This article presents a new approach to the reconstruction of massive defects of the lip and midface using a free flap in combination with a lip-switch flap. This was used in 10 patients. One-third to one-half of the upper lip was excised in seven patients, one-third of the lower lip was excised in one patient, and both the upper and lower lips were excised (one-third each) in two patients. All patients had maxillectomies, with or without mandibulectomies, in addition to full-thickness resections of the cheek. A switch flap from the opposite lip was used for reconstruction of the oral commissure and oral sphincter, and a rectus abdominis myocutaneous flap with two or three skin islands was used for reconstruction of the through-and-through defect in the midface. Free flap survival was 100 percent. All patients had good-to-excellent oral competence, and they were discharged without feeding tubes. A majority (80 percent) of the patients had an adequate oral stoma and could eat a soft diet. All patients have a satisfactory postoperative result. Immediate reconstruction of defects using a lip-switch procedure creates an oral sphincter that has excellent function, with good mobility and competence. This is a simple procedure that adds minimal operative time to the free-flap reconstruction and provides the patient with a functional stoma and acceptable appearance. The free flap can be used to reconstruct the soft tissue of the intraoral lining and external skin deficits, but it should not be used to reconstruct the lip.  相似文献   

18.
The hypothesis was tested that monozygotic (MZ) and dizygotic (DZ) twins, with their lower average birth weight, have higher adult blood pressure than their singleton brothers or sisters. From the Netherlands Twin Registry, 261 twin families were recruited from a young adult and an older adult cohort with mean ages of 26.2 and 50.4 respectively. These families yielded 204 MZ twins with 71 singleton siblings and 271 DZ twins with 103 of their singleton siblings. Anti-hypertensive medication use of these 649 participants was assessed twice with a two-year interval. Resting blood pressure was measured thrice during a standardized laboratory protocol. In spite of a significant difference in birth weight (1036 gram), no differences were found in anti-hypertensive medication use at both time points between twins and singletons nor between their resting laboratory diastolic or systolic blood pressure. These results applied to each gender and to both age cohorts. Limiting the analyses to matched twin-sibling pairs of the same families and taking current weight and height into account did not change the results; no evidence was found for a twin-singleton difference. It was concluded that estimates of genetic and environmental contributions to blood pressure deriving from twin studies do not appear to be biased and may be generalized to singletons. Our results suggest that the lower birth weight in twins does not reflect the intrauterine disadvantage described by the Barker hypothesis.  相似文献   

19.
Six larval forms of the bufonid genus Ansonia from Borneo share the following synapomorphies: cup-like, ventral oral disc; an expanded post-dental portion of the lower lip, which has a papillate margin; upper keratinized jaw sheath divided; body markedly flattened ventrally; eyes set relatively far back on the body. All of these tadpoles live on the bottom in strong currents, except for larval Ansonia leptopus , which lives in drifts of dead leaves that accumulate in eddies within streams. These larval forms differ among themselves in body shape, development of inframarginal papillae on the lower lip, size of the gap between the keratinized parts of the upper jaw sheath, width of the post-dental portion of the lower lip, relative lengths of upper and lower rows of labial teeth, and arrangement of the gut coils. One form has an abdominal sucker. Changes in these characters are not correlated; the derived condition in one character is not always associated with the derived state in another. Consequently, these tadpoles cannot be arranged in a simple morphocline from least to most derived, again with the exception of A. leptopus , which is the least modified in all respects. Although tadpoles of Ansonia resemble those of the neotropical bufonid genus Atelopus in general specialization for benthic life in flowing water, they differ from that group in body form and details of the oral disc.  相似文献   

20.
Structural organization of the epithelium of the lips and associated structures of the Indian major carp,Catla catla, is described. The upper lip is thin and is associated on its dorsal side with a membranous fold of skin and the rostral cap. In contrast, the lower lip is thick and very conspicuous. It is associated on its ventral side with a fold of skin between it and the ventral head skin. The lower lip is divided into a non-projectile portion, a projectile portion and an intermediate groove region. The projectile portion remains folded covering a part of the ventral head skin when the mouth is closed. Their role in relation to the formation of the characteristic feeding tube is discussed. The epithelium of the lips and associated structures is stratified in nature and is composed of the epithelial cells, mucous cells, club cells, lymphocytes and the taste buds. The mucous cells are small, few or even absent and do not appear to secrete profusely at the surfaces of the upper and the lower lips. This suggests that the lips inCatla catla, which feeds on micro-organisms, do not need extra lubrication for protection against abrasion during feeding. In the epithelium at the folds of skin, the voluminous mucous cells secrete profusely and provide extra lubrication to their surface. This reduces the resistance to surface drag during stretching and enables the jaws to protrude with increasing efficiency and swiftness. The club cells are developed additionally to complement the mucous cells in the rostral cap and the upper lip epithelium. Their primary function appears protective in some way, which needs further confirmation. The taste buds, though few in the lower lip, are located in a good number in the upper lip on the characteristic epithelial papillae-like projections, and are projected at the surface. These have been associated with the acute gustatory sense of the fish. The taste buds are absent on the folds of skin where they may not be of much significance.  相似文献   

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