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1.
Early identification of a syndrome at birth is of paramount importance for genetic counselling and possible prevention. Often malformation of the hands and fingers are cardinal manifestations of recognizable syndromes. As there are no published standards for hand and finger size for Malay newborn infants, this study was undertaken to establish normal values for hand, middle finger and palmar lengths, and their indices. A cross-sectional study was done on 509 consecutive newborn Malay babies between 34 and 42 weeks of gestation. Measurements were made on the right hand according to the recommended guidelines of Bergsma & Feingold (1975). The mean values for the measurements did not differ significantly between boys and girls, or change with gestation. For the whole group the mean value for total hand length was 64.4 +/- 3.42 mm, middle finger length 37.1 +/- 2.91 mm, palmar length 27.4 +/- 2.15 mm, finger index 0.425 +/- 0.03 and palmar index 0.58 +/- 0.03. A comparison with published measurements for newborns of different racial origin shows significant differences for the total hand length, middle finger length and palm length from Indian and Jewish infants, but not from Japanese infants. The indices were similar in Malay, Indian, Jewish and Japanese newborn infants.  相似文献   

2.
At a greater number of humid preparated human hands, all the ligamentous supports of the digital tendon sheath were exposed and their dimensions were determined. The osteofibrous channels, which contain the long flexor tendons of the digits, were bounded on the one hand by transversely concave shaft areas of the phalanges and the palmar ligaments and on the other side by the fibrous parts of the tendon sheath. From the second to the 5th finger, it has a regular extension of length, which begins proximal at the heads of the metacarpal bones and runs distal to the base of the nail phalanx. In some cases, there is a continuous communication between the digital tendon sheath of the little finger and the carpal synovial sheath. The tendon sheath of the flexor pollicis longus muscle in comparison with it is always in an open communication with the radial synovial sac of the wrist. At the fibrous supports of the digital tendon sheath, one can find constant and inconstant ligamentous structures. Regular shaped ligaments consist of annular fibers (A1 to A5). The proximal complex of fiber supports is a formation of the A1 and A2 ligaments. The band A1 can be divided into 2 ligaments both of roughly equal length, which lay between the head of the metacarpal bone and the base of the proximal phalanx. The strongest fibrous support of the whole digital tendon sheath represents the band A2. It is attached to the midth of the proximal phalanx and increases in strength from proximal to distal. The middle length varies between 6.7 mm at the thumb and 18.7 mm at the middle finger. The distal margin is strengthened by fibrocartilage tissue to be in accordance with the important function as a pulley. The annular band A4 forms the distal supporting complex height above the shaft of the middle phalanx. At the 2nd to the 5th finger it is, with a middle length of 6 to 7 mm, very much shorter than A2 and restrains first of all the tendon of the flexor digitorum profundus muscle. In the area of the interphalangeal joints, we can find the annular bands A3 and A5, which fiber texture is formed variable. Both ligaments are attached on either both sides with the joint capsule and the palmar plate. The other inconstant supports of the digital sheaths are systematically recorded indeed (C1 to C3), but only in exceptional cases they exist of cruciform fibers (Lig. cruciatum).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

3.
A new species of mudskipper,Periophthalmus spilotus, is described on the basis of 16 specimens from Sumatra, Indonesia. It differs from other species ofPeriophthalmus by the following combination of characters: pelvic fins totally united into rounded disk; first dorsal fin high, greyish, no spots on fin nor elongate spines; second dorsal fin typically with 14 total elements; anal fin typically with either 14 or 15 total elements; length of anal-fin base 21.8–29.0% SL; and length of second dorsal-fin base 22.5–26.7% SL. This species is most similar to, and probably most closely related to,P. chrysospilos.  相似文献   

4.
Two male Florida manatees (Trichechus manatus latirostris) demonstrated sensitive tactile discrimination in a two‐alternative forced choice task, using a modified staircase method. Stimuli were acrylic plates with vertical gratings of ridges and grooves. The standard stimulus, present on every trial, had 2 mm gratings and the comparison stimuli had wider gratings. The blindfolded subjects were trained to demonstrate discrimination by pressing the target with wider gratings. Discrimination thresholds (75% correct) for the subjects were 2.05 mm and 2.15 mm, corresponding to Weber fractions of 0.025 and 0.075, respectively. These results indicate thresholds on similar stimuli comparable to humans (index finger tasks) and better than harbor seals, Phoca vitulina, and the closely related Antillean manatee, Trichechus manatus manatus. Memory for the tactile task was quite stable for both subjects, over 2 yr in the case of one of the subjects. Video analysis of responses indicated that bristle‐like hairs, perioral bristles, and skin on the oral disk were involved in the discrimination response.  相似文献   

5.
Deep defects of the hand and fingers with an unhealthy bed exposing denuded tendon, bone, joint, or neurovascular structures require flap coverage. However, the location and size of the defects often preclude the use of local flap coverage. Free-flap coverage is often not desirable either, because the recipient vessels may be unhealthy from surrounding infection or trauma. In such situations, a regional pedicled flap is preferable. A solution to this is the heterodigital arterialized flap. This flap is supplied by the digital artery and a dorsal vein of the finger for venous drainage. Unlike the neurovascular island flap, the digital nerve is left in situ in the donor finger, thus avoiding many of the neurologic complications associated with the Littler flap. The digital artery island flap is centered on the midlateral line of the donor finger. It extends from the middorsal line to the midpalmar line. The maximal length of the flap is from the base of the finger to the distal interphalangeal joint. By preserving the pulp and the digital nerve, a sensate pulp on the donor finger remains that reduces donor-finger morbidity and also preserves fingertip cosmesis. Twenty-nine flaps were performed in 29 patients and the outcomes in the donor finger and the reconstructed finger were reviewed. The flap survival was 100 percent. There were no cases of flap ischemia or flap congestion. Good venous drainage of the flap through the additional dorsal vein was helpful in preventing the occurrence of early postoperative venous congestion, which is common in island flaps of the fingers, which depend on only the venae comitantes for drainage. Donor-finger morbidity, measured in terms of range of motion and two-point discrimination in the pulp, was minimal. Ninety-seven percent of the donor fingers achieved excellent or good total active motion according to the criteria of Strickland and Glogovac. Pulp sensation in the donor fingers was normal in 28 of the 29 donor fingers. No cold intolerance of the donor finger or the adjacent finger is reported in this series.  相似文献   

6.
 A new liparid, Careproctus parvidiscus, is described on the basis of a single specimen (177 mm in standard length) collected from the southern Okhotsk Sea, off Shiretoko Point, Hokkaido, Japan, at 400–700 m depth. It is distinguished from other congeners by the following combination of the characters: 50 dorsal fin rays, 44 anal fin rays, 10 + 47 = 57 vertebrae, 2 pleural ribs, 14 pyloric caeca being slender and pointed, 2 suprabranchial pores, narrower gill opening, longer lower lobe of pectoral fin, base of uppermost pectoral fin ray almost on a level with center of eye, rudimentary disk, dusky peritoneum, and black stomach. Received: June 13, 2001 / Revised: December 7, 2001 / Accepted: December 22, 2001  相似文献   

7.
A new species of the genus Amolops Cope,1865 is described from Xinduqiao,Kangding,Sichuan.It was previously identified as Amolops kangtingensis,which is synonymized to Amolops mantzorum in this study.The new species,Amolops xinduqiao sp.nov.,is distinguished from all other congeners by the following combination of characters:(1) medium body size,adult males SVL 41.2-47.5 mm (n=15,average 43.9 mm),adult females SVL 48.5-56.6 mm (n=15,average 52.5 mm);(2) head length equal to width or slightly wider than long;(3) tympanum small,but distinct;(4) vomerine teeth in two tiny rows,separated by a space about one vomerine teeth row;(5) bony projections on lower jaw absent;(6) dorsolateral folds usually absent;(7) tarsal folds or glands on tarsus absent;(8) circummarginal groove on disc of finger Ⅰ absent;(9) tibiotarsal articulation reaching nostril or beyond;(10) webs of toe Ⅳ reaching to distal articulation,other toes fully webbed to disc;and (11) vocal sac absent in males.  相似文献   

8.
Existing hypotheses on the mode of disk formation in the photoreceptor cells of mammals appear to be incompatible: (1) plasma membranes of adjacent evaginations form a disk which, subsequently, is internalized by a disk rim; (2) pinocytotic vesicles are pinched off from the plasma membrane and fuse into a larger vesicle, which flattens and forms a disk. We have studied the development of the cone outer segment and the disk formation in Tupaia belangeri by transmission electron microscopy. During the first two postnatal weeks, the distal part of the single cilium, which is inserted apically on the inner segment, becomes balloon-shaped. Apical to the axoneme, it contains tubular and vesicular material, which, most probably, has been detached from the axonemal microtubules. These tubules and vesicles do not contribute to disks. The balloon-shaped expansion, later retained as the ciliary backbone, establishes the contact with the pigment epithelium. Formation of disks, from the 12-day-old Tupaia onwards, occurs between adjacent evaginations at the outer segment base. The initial disk rims are “hooked” to the ciliary axonemal microtubules. The axonemal microtubules are involved in the initiation and in the alignment of the disks. Disk rim formation and, thus, internalization of disks proceeds from the base to the apex of the outer segment, that is, from the younger to the older disks. In the adult Tupaia, an uneven progression of disk rim formation on both sides of the axoneme is found among consecutive disks. The seemingly incompatible hypotheses on the mode of disk formation reflect a heterochrony of the internalization of membranes and of the disk formation among different mammals and, possibly, between cones and rods. Received: 24 July 1997 / Accepted: 10 September 1997  相似文献   

9.
The connection of functional modules is effective for the design of DNA binding molecules with the desired sequence specificity. C(2)H(2)-type zinc finger proteins have a tandemly repeated array structure consisting of independent finger modules and are expected to recognize any DNA sequences by permutation, multi-connection, and the substitution of various sets of zinc fingers. To investigate the effects of the replacement of the terminal finger on the DNA recognition by other fingers, we have constructed the three zinc finger peptides with finger substitution at the N- or C-terminus, Sp1(zf223), Sp1(zf323), and Sp1(zf321). From the results of gel mobility shift assays, each mutant peptide binds preferentially to the target sequence that is predicted if the fingers act in a modular fashion. The methylation interference analyses demonstrate that in the cases of the N-terminal finger substitution mutants, Sp1(zf223) and Sp1(zf323), the N-terminal finger recognizes bases to different extents from that of the wild-type peptide, Sp1(zf123). Of special interest is the fact that the N-terminal finger of the C-terminal finger substitution mutant, Sp1(zf321), shows a distinct base recognition from those of Sp1(zf123) and Sp1(zf323). DNase I footprinting analyses indicate that the C-terminal finger (active finger) induces a conformational change in the DNA in the region for the binding of the N-terminal finger (passive finger). The present results strongly suggest that the extent of base recognition of the N-terminal finger is dominated by the binding of the C-terminal finger. This information provides an important clue for the creation of a zinc finger peptide with the desired specificity, which is applicable to the design of novel drugs and biological tools.  相似文献   

10.
We recorded somatosensory evoked potentials (SEPs) in scalp EEGs during stimulation of the median nerve, the ulnar nerve and the individual digits in 3 normal subjects and in 1 epilepsy patients. In this patient we also measured SEPs from chronically indwelling subdural grid electrodes during electrocorticography (ECoG). We applied dipole modelling techniques to study the 3-dimensional intracerebral locations and time activities of the neuronal sources underlying stimulation of different peripheral receptive fields. The sources underlying median nerve SEPs were located an average of 10.8 mm lateral inferior to those underlying ulnar nerve SEPs. Digit SEP sources showed a somatotopic arrangement from lateral inferior to medial superior in the order thumb, index finger, middle finger, ring finger and little finger, with some overlap or reversal for adjacent digits. The average distance between thumb and little finger was 12.5 mm. Thumb, index finger and middle finger were clustered around median nerve cortical representation, whereas ring finger and little finger were arranged around ulnar nerve cortex. In the epilepsy patient, the source localizations obtained in scalp EEGs showed good agreement with those on ECoGs. We conclude that SEPs recorded in scalp EEGs can be used to study functional topography of human somatosensory cortex non-invasively.  相似文献   

11.
Paeonia decomposita Hand.-Mazz.subsp,rotundiloba D.Y.Hong is here raised to the specific rank,P.rotundiloba (D.Y.Hong) D.Y.Hong,based on its distinctiveness of four diagnostic characters:number of carpels;height of disk; number of leaflets of the lower leaves,and shape of the terminal leaflets; and unpublished molecular data.Paeonia rotundiloba differs distinctly from P.decomposita in having carpels mostly 3,less often 2 or 4,very rarely 5 (vs.almost always 5,very occasionally 4 or 3),disk 8-15 mm high (vs.4-9.6 mm),leaflets mostly 19-39(vs.29-63) in number,and ratio of length to width of the terminal leaflets 1.09-1.93 (vs.1.81-2.99).  相似文献   

12.
A new species of liparid fish Careproctus surugaensis is described from a single specimen collected between 1,450 and 1,570 m depth on the northern part of Suruga Trough, Suruga Bay, Japan. It can be distinguished from all currently recognized congeners by the following combination of characters: 50 total vertebrae, 47 dorsal-fin rays, 39 anal-fin rays, 32 pectoral-fin rays, 10 principal caudal-fin rays, pectoral proximal radials 4 (first to third with notches); trilobate teeth on both jaws, gill slit 7.1 % SL, extending in front of 7th pectoral fin ray base; maximum body depth 19.1 % SL, disk length 7.9 % SL, anus midway between posterior margin of pelvic disk and anal-fin origin; body and fins light orange except blackish peritoneum.  相似文献   

13.
Synchronous zooid formation in Ulva pertusa Kjellman was induced in excised disks maintained in sterilized seawater at 20°C, 12:12 h L:D cycle and fluorescent light at 100 μmol photons m 2s 1. Zooids were reieased from mature disk tissue on the morning of the second or the third day after excision. The degree of zooid formation was found to be dependent on disk size and the region of the mother thalius from which the disk tissue was excised. Zooid formation was induced in more than 90% of small disks (0.9 mm in diameter) which were taken from the margins of the Ulva thalli. When disks were incubated together with a perforated mother thalius, the disks remained sterile. The presence of maturation inhibitors in vegetative thalli is suggested.  相似文献   

14.
Transverse landmarks have recently been determined to predict the proximal and distal edges of the A1 pulley for trigger finger release. Percutaneous A1 pulley release has been discouraged for the border digits because of the risk of injury to the neurovascular structures of the index and small fingers. The purpose of the study was to identify longitudinal surface landmarks to prevent injury to the neurovascular bundles during percutaneous A1 pulley release of the ulnar and radial border digits. Longitudinal surface landmarks were identified and marked on 29 cadaver hands. Proximal and distal landmarks for the longitudinal vector through which the A1 pulley of the small finger was released include the midline of the proximal digital crease and the scaphoid tubercle. Proximal and distal landmarks for the longitudinal line through which the index finger A1 pulley was released include the midline of proximal digital crease and radial edge of the pisiform. Longitudinal incisions were performed between these landmarks, straight through the skin and deep enough to score the A1 pulley. The distance of the medial edge of the neurovascular structures from the longitudinal incision in the A1 pulley was measured for each small finger and index finger. Using these longitudinal landmarks for the index and small fingers, none of the neurovascular structures was injured while performing these longitudinal incisions through the skin, scoring the A1 pulley. In fact, the average distance for the neurovascular structures from the longitudinal vector of the small finger was 5.4 +/- 1.4 mm radially and 6.7 +/- 1.9 mm ulnarly. The average distance for the neurovascular structures from the longitudinal line of the index finger was 8.5 +/- 1.8 mm radially and 6.2 +/- 1.7 mm ulnarly. Based on the findings of this anatomical study, these longitudinal landmarks can be used to avoid injury to neurovascular structures in the management of trigger finger involving the border digits with steroid-injection, open, or percutaneous A1 pulley release.  相似文献   

15.
In the human hand, independent movement control of individual fingers is limited. One potential cause for this is mechanical connections between the tendons and muscle bellies corresponding to the different fingers. The aim of this study was to determine the tendon displacement of the flexor digitorum superficialis (FDS) of both the instructed and the neighboring, non-instructed fingers during single finger flexion movements. In nine healthy subjects (age 22–29 years), instructed and non-instructed FDS finger tendon displacement of the index, middle and ring finger was measured using 2D ultrasound analyzed with speckle tracking software in two conditions: active flexion of all finger joints with all fingers free to move and active flexion while the non-instructed fingers were restricted. Our results of the free movement protocol showed an average tendon displacement of 27 mm for index finger flexion, 21 mm for middle finger flexion and 17 mm for ring finger flexion. Displacements of the non-instructed finger tendons (≈12 mm) were higher than expected based of the amount of non-instructed finger movement. In the restricted protocol, we found that, despite minimal joint movements, substantial non-instructed finger tendon displacement (≈9 mm) was still observed, which was interpreted as a result of tendon strain. When this strain component was subtracted from the tendon displacement of the non-instructed fingers during the free movement condition, the relationship between finger movement and tendon displacement of the instructed and non-instructed finger became comparable. Thus, when studying non-instructed finger tendon displacement it is important to take tendon strain into consideration.  相似文献   

16.
Summary Flies (Musca domestica) avoid danger by initiating a rapid jump followed by flight. To identify the visual cues that trigger the escape response in the housefly, we measured the timing and probability of escapes when the fly was presented with a variety of visual stimuli created by moving targets toward it. Our results show that an escape response is triggered by an approaching dark disk, but not by a receding dark disk. On the other hand, a bright disk elicits escape only when it recedes. A disk with black and white rings is less effective at eliciting escape than is a dark solid disk of the same size. This indicates that the darkening contrast produced by an approaching stimulus is a more crucial parameter than expansion cues contained in the optical flow. Escape is also triggered by a horizontally moving dark edge, but not by a moving bright edge or by a grating. An examination of several visual parameters reveals that the darkening contrast, measured from the onset of stimulation to the start of escape is nearly constant for a variety of stimuli that trigger escape reliably. Thus darkening contrast, coupled with motion may be crucial in eliciting the visually evoked escape response. Other visual parameters such as time-to-contact or target angular velocity seem to be relatively unimportant to the timing of escapes.Abbreviations P s Probability of successful escape - r disk radius of disk target - r arena radius of shielding arena - v disk linear velocity of disk target - v edge linear velocity of edge - d disk angular velocity of disk target boundary - edge angular velocity of edge - escape target distance at escape - d start target distance before onset of target movement - h edge height of the edge above fly - x start distance from corner of triangle to start position of edge (0 or 50 mm) - x escape distance from corner of triangle to the position of the edge when the fly escapes - x center distance from corner of triangle to point above the center of the pad - x total distance from the corner of the triangle to the base (height of triangle = base of triangle)  相似文献   

17.
We describe a new species of torrent-dwelling ranid frog of the genus Amolops from western to peninsular Thailand. Amolops panhai, new species, differs from its congeners by the combination of: small body, males 31-34 mm, females 48-58 mm in snout-vent length; head narrower than long; tympanum distinct; vomerine teeth in short, oblique patches; first finger subequal to second; disc of first finger smaller than that of second, with circummarginal groove; no wide fringe of skin on third finger; toes fully webbed; outer metatarsal tubercle present; supratympanic fold present; dorsolateral fold indistinct; axillary gland present; horny spines on back, side of head and body, and chest absent; large tubercles on side of anus absent; glandular fold on ventral surface of tarsus absent; nuptial pad and paired gular pouches present in male; white band along the upper jaw extending to shoulder absent; larval dental formula 7(4-7)/3(1). This new species is the second anuran discovered which has a disjunct distribution around the Isthmus of Kra.  相似文献   

18.
The effect of temperature on the respiration rate of potato tuber slices has been analyzed in terms of the Arrhenius equation. Freshly cut disks, irrespective of thickness, show a linear response to increasing temperature up to 30° with an activation energy (E) of approximately 12.0 Kcal. Aged disks less than 1.0 mm thick also give a linear response with E similar to that of fresh disks. With aged disks above 1.0 mm thick there is a loss of linearity above 20° and E falls to about 4.0 Kcal indicating that respiration becomes rate-limited by a diffusion process. This departure from linearity can be corrected by raising the oxygen tension or by subdivision of thick disks to give thin slices. It is concluded that the respiration of aged disks is rate-limited by oxygen deficiency and that the inverse relationship between respiration rate and disk thickness is in large part attributable to this factor.  相似文献   

19.
The zinc finger domain of the Wilms tumor suppressor protein (WT1) contains four canonical Cys(2)His(2) zinc fingers. WT1 binds preferentially to DNA sequences that are closely related to the EGR-1 consensus site. We report the structure determination by both X-ray crystallography and NMR spectroscopy of the WT1 zinc finger domain in complex with DNA. The X-ray structure was determined for the complex with a cognate 14 base-pair oligonucleotide, and composite X-ray/NMR structures were determined for complexes with both the 14 base-pair and an extended 17 base-pair DNA. This combined approach allowed unambiguous determination of the position of the first zinc finger, which is influenced by lattice contacts in the crystal structure. The crystal structure shows the second, third and fourth zinc finger domains inserted deep into the major groove of the DNA where they make base-specific interactions. The DNA duplex is distorted in the vicinity of the first zinc finger, with a cytidine twisted and tilted out of the base stack to pack against finger 1 and the tip of finger 2. By contrast, the composite X-ray/NMR structures show that finger 1 continues to follow the major groove in the solution complexes. However, the orientation of the helix is non-canonical, and the fingertip and the N terminus of the helix project out of the major groove; as a consequence, the zinc finger side-chains that are commonly involved in base recognition make no contact with the DNA. We conclude that finger 1 helps to anchor WT1 to the DNA by amplifying the binding affinity although it does not contribute significantly to binding specificity. The structures provide molecular level insights into the potential consequences of mutations in zinc fingers 2 and 3 that are associated with Denys-Drash syndrome and nephritic syndrome. The mutations are of two types, and either destabilize the zinc finger structure or replace key base contact residues.  相似文献   

20.
Abstract Paeonia decomposita Hand.‐Mazz. subsp. rotundiloba D. Y. Hong is here raised to the specific rank, P. rotundiloba (D. Y. Hong) D. Y. Hong, based on its distinctiveness of four diagnostic characters: number of carpels; height of disk; number of leaflets of the lower leaves, and shape of the terminal leaflets; and unpublished molecular data. Paeonia rotundiloba differs distinctly from P. decomposita in having carpels mostly 3, less often 2 or 4, very rarely 5 (vs. almost always 5, very occasionally 4 or 3), disk 8–15 mm high (vs. 4–9.6 mm), leaflets mostly 19–39 (vs. 29–63) in number, and ratio of length to width of the terminal leaflets 1.09–1.93 (vs. 1.81–2.99).  相似文献   

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