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1.
M H Mogard J R Reeve J E Shively C M Ben-Avram V E Eysselein J H Walsh 《Regulatory peptides》1986,14(4):313-321
Neurotensin-like immunoreactivity can be detected in extracts of canine upper gastrointestinal mucosa when measured by carboxyl terminal but not by amino terminal antibodies to neurotensin. The nature of this immunoreactive material was characterized by complete purification on gel filtration and HPLC followed by peptide microsequence analysis. The structure obtained was Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-(Leu), identical in structure to the carboxyl terminal decapeptide of neurotensin. It cannot, however, be excluded that this neurotensin decapeptide was generated from a larger neurotensin-like peptide during the extraction procedure by a physiological or artificial enzymatic process. Since carboxyl terminal neurotensin fragments containing eight or more residues have full biological activity, this peptide may be responsible for neurotensin-like biological activities within the mucosa of, or after release from, the upper gut. 相似文献
2.
Overhead work is a major cause of upper extremity work-related musculoskeletal disorders (WMSD). In this paper, the potential effects of a Passive Upper-Limb Exoskeleton (PULE) were evaluated in the tasks of overhead works. This proposed PULE has a higher degree of freedom and does not impede the user's upper limb movements. Fifteen male volunteers participated in the study by performing the repeated overhead bolt installation tasks. The electromyographic (EMG) values of anterior deltoid (AD), mid deltoid (MD), descending trapezius (TR), and triceps (TB) of the left and right arms of the participants were measured at three different overhead task heights with Intervention (with/without the PULE). Moreover, the rankings of perceived discomfort (RPD) obtained on the neck, shoulders, upper arms, forearms, upper back, waists, and legs were rated for each participant. The preliminary experiment results show that the initial nEMG of right anterior deltoid (AD) decreased by 38.5%, median nEMG values decreased by 45.1%, and total RPD decreased by 52.4%. The use of the PULE could bring the benefits of less upper extremity muscle contraction and lower RPD compared to the non-use, which may potentially reduce or slow down the level of upper extremity WMSD across the overhead work. 相似文献
3.
折枝处理降低了叶片下表皮蒸腾速率,提高了上表皮角质蒸腾占叶总蒸腾的比值,使角质蒸腾的上下振幅增大。2 m 高度叶片低于1 m 高度叶片的上表皮角质蒸腾。位于黑纸套内及阴处的叶片上表皮角质蒸腾占叶总蒸腾的比值均增大,而全日上表皮角质蒸腾的振幅却减少。 相似文献
4.
The primary motor cortex (M1) was mapped with intracortical microstimulation (ICMS) in a 15 year-old macaque whose right upper extremity was amputated at the shoulder joint prior to 2 years of age. Movements of the right shoulder girdle and stump were evoked by ICMS throughout the left M1 upper extremity region. The size of the left M1 upper extremity region contralateral to the amputated arm was not appreciably different from the size of the right upper extremity region contralateral to the intact arm. Long stimulus trains and/or higher stimulus currents were needed to evoke detectable movements at significantly more loci in the left than in the right M1 upper extremity region. These observations would be consistent with unmasking of a high threshold representation of shoulder musculature that normally exists throughout the central core of the upper extremity region, where it underlies a lower threshold representation of the distal forelimb. Alternatively, invasion of the de-efferented distal forelimb core by surrounding shoulder representation may have occurred. Differences between the limited M1 reorganization observed in the present study and the more extensive reorganization of S1 observed in other studies may reflect fundamental differences between M1 and S1, and/or differences in the extent of de-efferentation versus deafferentation. 相似文献
5.
描述了自陕西省发现的毛茛科乌头属一新种,圆盔乌头(Aconitum rotundocassideum)。由于具有相似的体态和盔形上萼片,此种与特产云南省的粗茎乌头在亲缘上很相近,与后者的区别特征见正文。 相似文献
6.
描述了自陕西省发现的毛莨科乌头属一新种,圆盔乌头(Aconitum rotundocassideum)。由于具有相似的体态和盔形上萼片,此种与特产云南省的粗茎乌头在亲缘上很相近,与后者的区别特征见正文。 相似文献
7.
Upper jaw protrusion is hypothesized to improve feeding performance in teleost fishes by enhancing suction production and stealth of the feeding event. However, many cyprinodontiform fishes (mid-water feeders, such as mosquitofish, killifish, swordtails, mollies and pupfish) use upper jaw protrusion for "picking" prey out of the water column or off the substrate; this feeding mode may require improved jaw dexterity, but does not necessarily require increased stealth and/or suction production. We describe functional aspects of the bones, muscles and ligaments of the anterior jaws in three cyprinodontiform genera: Fundulus (Fundulidae), Gambusia and Poecilia (Poeciliidae). All three genera possess a premaxillomandibular ligament that connects the premaxilla of the upper jaw to the mandible. The architecture of this ligament is markedly different from the upper-lower jaw connections previously described for basal atherinomorphs or other teleosts, and this loose ligamentous connection allows for more pronounced premaxillary protrusion in this group relative to closely related outgroup taxa. Within poeciliids, a novel insertion of the second division of the adductor mandibulae (A2) onto the premaxilla has also evolved, which allows this jaw adductor to actively retract the premaxilla during mouth closing. This movement is in contrast with most other teleosts, where the upper jaw is retracted passively via pressure applied by the adduction of the lower jaw. We postulate that this mechanism of premaxillary protrusion mediates the cyprinodontiforms' ability to selectively pick specific food items from the water column, surface or bottom, as a picking-based feeding mechanism requires controlled and coordinated "forceps-like" movements of the upper and lower jaws. This mechanism is further refined in some poeciliids, where direct muscular control of the premaxillae may facilitate picking and/or scraping material from the substrate. 相似文献
8.
King RL Rosenberger AL Kanda LL 《Folia primatologica; international journal of primatology》2005,76(6):303-324
In this pilot study, we used an unsupervised learning algorithm for self-organization and pattern matching to create feature maps that can be applied to morphological problems. We designed a network to analyze 83 first and/or second upper and lower molar sets representing 13 anthropoid primate species, based on three-dimensional measures obtained from laser-digitized, virtual specimens. As shown in a comparison with a principal-component analysis of the virtual specimens, the artificial neural network approach provided more biologically meaningful information than the conventional multivariate analysis approach. The methodology discovered partitions and hierarchical clusters consistent with anthropoid systematics, from the species (or subspecies) level to the highest categories, by sorting and allocating upper and lower molar teeth. As one might expect, measures of upper molars were richer in phenetic information than those of lower molars, even among the anatomically diverse platyrrhines. We also show that reducing taxonomic noise (i.e. biological variation) by limiting the analysis to a monophyletic subset improves discrimination. 相似文献
9.
Perforation of the intestine by an ingested foreign body usually results in peritonitis or abscess formation and the treatment is surgical. In one case the duodenum was perforated by a toothpick, and hemorrhage from the upper gastrointestinal tract occurred 3 months later. Diagnosis and management were accomplished by operative endoscopy. 相似文献
10.
Carvajal A Ortega S Del Olmo L Vidal X Aguirre C Ruiz B Conforti A Leone R López-Vázquez P Figueiras A Ibáñez L 《PloS one》2011,6(5):e19819
Background
Selective serotonin reuptake inhibitors (SSRIs) have been associated with upper gastrointestinal (GI) bleeding. Given their worldwide use, even small risks account for a large number of cases. This study has been conducted with carefully collected information to further investigate the relationship between SSRIs and upper GI bleeding.Methods
We conducted a case-control study in hospitals in Spain and in Italy. Cases were patients aged ≥18 years with a primary diagnosis of acute upper GI bleeding diagnosed by endoscopy; three controls were matched by sex, age, date of admission (within 3 months) and hospital among patients who were admitted for elective surgery for non-painful disorders. Exposures to SSRIs, other antidepressants and other drugs were defined as any use of these drugs in the 7 days before the day on which upper gastrointestinal bleeding started (index day).Results
581 cases of upper GI bleeding and 1358 controls were considered eligible for the study; no differences in age or sex distribution were observed between cases and controls after matching. Overall, 4.0% of the cases and 3.3% of controls used an SSRI antidepressant in the week before the index day. No significant risk of upper GI bleeding was encountered for SSRI antidepressants (adjusted odds ratio, 1.06, 95% CI, 0.57–1.96) or for whichever other grouping of antidepressants.Conclusions
The results of this case-control study showed no significant increase in upper GI bleeding with SSRIs and provide good evidence that the magnitude of any increase in risk is not greater than 2. 相似文献11.
I. B. Knizhin S. J. Weiss B. E. Bogdanov S. S. Samarina E. Froufe 《Journal of Ichthyology》2006,46(1):34-43
A dwarf form of the Arctic grayling Thymallus arcticus, inhabiting a group of small lakes at the origin of the Yakchii stream, which flows into the Verkhnyaya Angara River (basin of Lake Baikal), has been found in the northeastern watershed of the Baikal and Lena basins. The form is similar to upper Lena populations in body coloration and the pattern of dorsal fin. Our comparison by meristic characters indicated that the grayling of the Yakchii Lakes is more similar to the fish from Kutima River (basin of the upper courses of the Lena River) than to the black Baikal grayling T. arcticus baicalensis. The presence in Lake Baikal of a population similar to upper Lena graylings may have three causes: (1) possible drainage from Baikal to the pra-Lena via ancient valleys of the Barguzin and the Upper Angara; (2) appearance of transit zones as a result of glacial or tectonic events during the periods of watershed development between the Baikal and Lena basins; (3) the upper Lena grayling could be an endemic of the Baikal basin which was replaced by graylings penetrating from the Yenisei basin and remained in the form of relic populations in the upper courses of certain tributaries of the northern and northeastern parts of Lake Baikal. 相似文献
12.
Shigeyoshi Yazaki 《Microbiology and immunology》1966,10(4):239-246
One hundred and twenty-one children showing symptoms of acute upper respiratory disease were bled during a period of nine months, from winter to summer, for detection of complement-requiring neutralizing (CRN) antibody against herpes simplex virus. Six of the cases, all from children under the age of 13 years, were unequivocally related to herpetic infection as evidenced by the presence of anti-herpes CRN antibody. During the same period, 144 other children who were normal healthy or suffering from unrelated non-febrile diseases were tested as controls; anti-herpes CRN antibody was not detected in any of them. Further, the age distribution of individuals with antibodies was compared between patients in the acute upper respiratory disease group and the control group. This analysis showed that approximately 5 to 7% of the acute upper respiratory diseases in the young children in this study would be attributed to herpetic infection. 相似文献
13.
The fungal flora in different parts of a beech forest ecosystem was investigated through a four year period as part of an IBP project. Both colony counts and direct measurements of fungal mycelium indicated that a vast majority of the fungal biomass is concentrated in the upper horizons of the soil, especially in the mull layer. The litter also contained large amounts of fungi when calculated per g dry weight, but still the litter fungi accounted for only a quite small percentage of the total fungal biomass. The fungi growing in direct contact with the living plants, i.e. in the rhizosphere and phylloplane, also accounted for only a few per cent of the total amount of fungi in the ecosystem.
On basis of direct measurements of fungal mycelium the total biomass was estimated to be about 100 g dry wt per m2 . However, no attempts were made to distinguish between living and dead hyphae, and a large proportion of the observed hyphae may very well be dead or inactive.
Qualitative studies revealed that the upper soil layers not only contained the largest amounts of fungal mycelium, but also by far the highest species diversity. Other parts of the ecosystem, e.g. the phylloplane, were often strongly dominated by one or a few species, whereas soil always contained a large variety of different types. 相似文献
On basis of direct measurements of fungal mycelium the total biomass was estimated to be about 100 g dry wt per m
Qualitative studies revealed that the upper soil layers not only contained the largest amounts of fungal mycelium, but also by far the highest species diversity. Other parts of the ecosystem, e.g. the phylloplane, were often strongly dominated by one or a few species, whereas soil always contained a large variety of different types. 相似文献
14.
Slips are frequently the cause of fall-related injuries. Identifying modifiable biomechanical requirements for successful recovery is a key prerequisite to developing task-specific fall preventive training programs. The purpose of this study was to quantify the biomechanical role of the upper extremities during the initial phase of a slip resulting in trunk motion primarily in the sagittal plane. Two groups of adults were examined: adults over age 65 who fell and adults aged 18–40 who avoided falling after slipping. We hypothesized that rapid shoulder flexion could significantly reduce trunk extension velocity, that adults who slipped would implement this as a fall avoidance strategy, and that younger adults who avoided falling would use this strategy more effectively than older adults who fell. The kinematics of the 12 younger adults and eight older adults were analyzed using a three-segment conservation of momentum model developed to represent the trunk, head, and upper extremities. The model was used to estimate the possible contribution of the upper extremities to reducing trunk extension velocity. The model showed that upper extremity motion can significantly reduce trunk extension velocity. Although the upper extremities significantly reduced the trunk extension velocity of both young and older adults (p<0.027), the reduction found for the young adults, 13.6±11.4%, was significantly larger than that of the older adults (5.8±3.4%, p=0.045). Given the potential for trunk extension velocity to be reduced by rapid shoulder flexion, fall prevention interventions focused on slip-related falls may benefit from including upper extremity motion as an outcome whether through conventional or innovative strategies. 相似文献
15.
Social status and season of birth: a study of a metropolitan area in the southeastern United States 总被引:2,自引:0,他引:2
An analysis of live birth statistics obtained from the Health Department of Fulton County, Georgia for 1967-1977 indicated that seasonal variation in birth was significantly related to maternal social status. Mothers were assigned to social status classification on the basis of whether they lived in an upper, upper middle, lower middle, or lower socioeconomic census tract. Periodic regression analysis and analysis of variance was applied to the data. Specific findings were 1) upper status groups showed no significant variation in births; 2) upper and lower middle classes showed a similar and a significant degree of seasonal variation with depressed birth levels from January-June and elevated levels from July-December; 3) lower class birth patterns showed more seasonal variation than the other classes; 4) the periodic curve accounted for 92.3% of the monthly variation in births for the lower class, 70.6% for the lower middle class, and 64.6% for the upper middle class; 5) the relationship between social status and seasonal variation in births held for both whites and non-whites; 6) seasonal variations were somewhat more marked for non-whites than for white in the lower and lower middle class; and 7) the observed relationship held throughout the 11 year period of observation. The results were of special concern given previous studies which found that children born in September-October entered school on the average earlier than other children and did less well in school than other students. Major findings were presented in graphic and tabular form. 相似文献
16.
The insect wing is formed from an epithelial sheet that folds during development to establish a saclike tissue with an upper and a lower epithelial monolayer. The adult cuticle formed by the upper and lower monolayers has a distinctive pattern of thickened regions called veins. The venation pattern on the lower surface matches that on the upper surface. As demonstrated by transposition of grafts from the upper monolayer, determination of venation pattern occurs prior to pupation in both wing monolayers. However, the pattern is not expressed until later in adult development. Expression of this determined pattern occurs autonomously in most circumstances. One circumstance in which the pattern fails to be expressed is in pieces of the upper monolayer that are isolated from the lower monolayer before adult cuticle deposition and expression of venation pattern. The only evident interaction between the two monolayers of the wing occurs during a 3-day period, 6–8 days after pupation. During this time, the basal laminae segregating upper monolayer from lower monolayer disappear, and the basal ends of cells form desmosomal junctions at the interface between upper and lower monolayer. Transposition as well as isolation of tissue fragments from the upper monolayer suggest that this interaction between the basal surfaces of the two monolayers is a prerequisite for evocation of venation pattern. 相似文献
17.
Persistent incontinence after toilet training in young girls and urinary tract infections or epididymitis in prepubertal boys should raise suspicion of an ectopic ureter. This often occurs in the context of duplication of kidney structures or other parenchymal abnormalities. The presence or absence of reflux affects surgical treatment, which may consist of ureteral reimplantation, ureteroureterostomy, and/or upper pole nephrectomy. 相似文献
18.
The cost of sexual reproduction is incurred when the current reproductive episode contributes to a a decline in future plant performance. To test the hypotheses that a trade-off exists between current sexual reproduction and subsequent clonal regeneration and that resources limit reproduction and regeneration, plants of the widespread moss Pterygoneurum ovatum were subjected to induced sporophytic abortion, upper leaf removal, and nutrient amendment treatments. Sexually reproducing plants were slower or less likely to produce regenerative structures (protonemata or shoots) and produced fewer regenerative tissue areas or structures. The ability and the timeline to reproduce sexually and regenerate clonally were unaffected by an inorganic nutrient amendment. However, when leaves subtending the sporophyte were removed, the sporophytes were less likely to mature, tended to take a longer time to mature, and were smaller compared to sporophytes from shoots with a full complement of upper leaves. Our findings indicate that plants investing in sexual reproduction suffer a cost of decreased clonal regeneration and indicate that sporophyte maturation is resource-limited, with upper leaves contributing to the nutrition of the sporophyte. This study represents only the second explicit experimental demonstration of a trade-off between sexual and asexual reproduction in bryophytes. 相似文献
19.
Excess skin of the upper lids is often accompanied by lateral overlap of skin with crow's feet because of the absence of fixation to the tarsal plate, giving the eye a sad, heavy look that often disturbs the lateral visual field. The accepted crescent-shaped blepharoplasty is somewhat convex, which is widest at the center of the lid with or without a lateral extension. However, in patients who have normal brow position or minimal eyebrow ptosis and whose main concern is the excess upper eyelid skin and lateral hooding, such a crescent excision may not suffice. A scalpel-shaped excision that is widest laterally and that tapers to a point medially will extirpate the maximal skin where it is most needed and overcome the skin excess in the lateral aspect of the upper lid. Between 1990 and 2002, 301 white patients (275 women and 26 men) between the ages of 33 and 79 years were operated on using the extended scalpel-shaped upper blepharoplasty technique. The follow-up period was more than 1 year. The lower margin of the incision is along the supratarsal crease, about 10 mm above the ciliary line. It begins medially about 1 cm above and lateral to the medial canthus. Above the lateral canthus, the skin marking is gently curved upward and outward, often within a natural skin crease or crow's feet to reach a little below and slightly beyond the lateral extremity of the eyebrow. The upper border of the incision joins the two extremities of the skin outline in a gentle convex curve. The general outline of the incision takes on the shape of a number 20 scalpel blade in which the maximal width is located laterally. Following excision of the excess skin and removal of protuberant fat pads if needed, suturing is executed from lateral to medial. The final suture line is in the form of an oblique flattened lazy S. Following the removal of the stitches on the fifth postoperative day, no wound dehiscence was noticed at the lateral scar zone. In the older individuals, due to the lax skin, the scar becomes scarcely noticeable with time and often falls within a pre-existent crow's feet crease. Elimination of some of the crow's feet was also demonstrated. In patients with visual field impairment, significant functional and visual improvement was achieved. Most patients mentioned a pleasing postoperative open "Oriental" look of the eyes. The extended scalpel-shaped upper blepharoplasty adequately deals with the hooding of the skin laterally. This technique overcomes the excess of skin in both vertical and horizontal directions, since in suturing the lateral part of the skin defect in an oblique plane, slack skin is taken up transversely, and the technique provides some indirect upward support to the lateral eyebrow. In the absence of crow's feet in the younger person, this technique is not recommended because the lateral part of this suture line is visible, especially if the scar widens. 相似文献
20.
Some herbivorous insects enhance their fitness using foraging strategies that allow them to find and colonize the best of
available resources within heterogeneous plants. The yellowheaded spruce sawfly, Pikonema alaskensis (Roh.) (Hymenoptera: Tenthredinidae), is a common defoliator that oviposits and feeds on the developing foliage of young
open-grown black spruce [Picea mariana (Mills) B.S.P.]. While female and male eggs are both laid throughout the crown, most eggs laid in the upper crown are female,
and more female than male late-instar larvae disperse acropetally, from the lower and mid-crown to the upper crown, to complete
juvenile development. Here we present results from 4 years of manipulative sleeve-cage experiments that were carried out to
evaluate the hypothesis that sex-biased oviposition-site selection and acropetal dispersal by P. alaskensis are adaptive responses to intra-tree variation in foliage quality. Survival and proportion of survivors that were female
were either the same (2 years) or significantly higher (2 years) for groups placed in the lower or mid-crown during early
instars, and then transferred acropetally during late instars to complete development in the upper crown, compared with those
forced to feed exclusively in the lower crown. This suggests that females benefited most from acropetal dispersal. Sex ratios
of survivors that had been forced to develop exclusively in the upper crown were usually more female biased than those of
survivors that developed exclusively in the lower crown, suggesting higher survival for female than for male larvae emerging
from eggs laid in the upper crown. Sex-biased egg allocation and larval dispersal appear to increase the survival of P. alaskensis by accounting for differential effects on male versus female larvae of phenology-independent temporal and spatial variations
in the quality of foliage within the heterogeneous crown of black spruce. 相似文献