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Probing pain threshold (PPT) assessments were conducted in the facial and oral sulci of maxillary central incisors and first molars of 10 periodontally healthy adults. All subjects were systemically healthy, free of pain, and reported no current medication usage. A computer-linked electronic probe, modified to deliver steadily increasing forces up to 200 grams, was used to collect the data. The system contained a subject operated "off-switch" which, upon activation, signaled the computer to record the subject's PPT. Assessments of each subject's PPTs were conducted on 3 separate occasions at 7-day intervals. Results indicated that the facial sulci of the incisors were the most pain sensitive. They displayed a mean PPT of 50.9 +/- 26.6 grams. The oral sulci of the incisors exhibited a mean PPT of 76.5 +/- 45.2 grams. Facial and oral sulci of the molars evidenced mean PPT values of 102.6 +/- 52.1 grams and 113.5 +/- 51.3 grams, respectively. These data suggest that sulci associated with incisor teeth are nearly twice as pain sensitive as sulci associated with molar teeth. In addition, facial sulci are significantly more pain sensitive than oral sulci. Data did not indicate a visit effect nor a side-of-mouth effect on PPT values.  相似文献   
13.
Denoting the nonnegative (resp. signed) integers byN (resp.Z) and the real numbers byR, letK R m andf: R m R. Thenf is astoring function (resp.packing function) onK wheneverf|(Z m K) is an injection into (resp. bijection onto)N. Unit translations gm of some P. Chowla [1961] polynomials are packing functions on the correspondingN m , and all compositions of these polynomials yield further packing functions on variousN r . We study this accessible family of packing functions, using standard properties ofordered trees to classify all those compositions, up to a simple equivalence, which define polynomial packing functions on eachN m . The numberc(m) of equivalence classes is an exponentially growing function for largem, whence the uniqueness conjecture of our prior two-dimensional work has no counterpart for largerm. We obtain the admissible degrees for composition polynomials inm variables; we describe the tre structures for all such polynomials with extremal degrees. Them-variable polynomials of least degree form a rather irregular numbera(m) of equivalence classes. Density considerations give some degree constraints on ageneral polynomial packing function whose domainK is the topological closure of a nonvoid open cone.  相似文献   
14.
A technique is described for using the advantages of a social systems approach when working with elderly persons in psychiatric distress. The technique is based on the assumption that the solution to a variety of human predicaments lies within the collective instrumental and affective resources of the client's social network. The vehicle for accomplishing this objective is the "Network Session" during which a mental health professional meets with the elderly person and members of his/her social network to help resolve the difficulty. A case report demonstrating use of the technique is included.  相似文献   
15.
Orbital fibroblasts (OFs) in thyroid-associated ophthalmopathy (TAO) are differentiated from pre-adipocytes and mature adipocytes; increased lipid and fat expansion are the major characteristics of ophthalmic manifestations. Human placental mesenchymal stem cells (hPMSCs) were reported to immunomodulate pathogenesis and suppress adipogenesis in TAO OFs. Here, we prepared transforming growth factor β (TGFβ, 20 ng/mL)-treated hPMSCs (TGFβ-hPMSCs) in order to enhance anti-adipogenic effects in vitro and in TAO mice. TAO OFs were grown in a differentiation medium and then co-cultured with hPMSCs or TGFβ-hPMSCs. TAO OFs were analyzed via quantitative real-time polymerase chain reaction, Oil red O staining, and western blotting. The results showed that TGFβ-hPMSCs reduced the expression of adipogenic, lipogenic, and fibrotic genes better than hPMSCs in TAO OFs. Moreover, the adipose area decreased more in TAO mice injected with TGFβ-hPMSCs compared to those injected with hPMSCs or a steroid. Further, TGFβ-hPMSCs inhibited inflammation as effectively as a steroid. In conclusion, TGFβ-hPMSCs suppressed adipogenesis and lipogenesis in vitro and in TAO mice, and the effects were mediated by the SMAD 2/3 pathways. Furthermore, TGFβ-hPMSCs exhibited anti-inflammatory and anti-fibrotic functions, which suggests that they could be a new and safe method to promote the anti-adipogenic function of hPMSCs to treat TAO patients.  相似文献   
16.
We have used cross-sectional scanning tunneling microscopy (STM) to study interface structure in arsenide/phosphide heterostructures grown by gas-source molecular beam epitaxy (GSMBE) and by low-pressure metalorganic vapor phase epitaxy (LP-MOVPE). High-resolution images of GSMBE samples consisting of GaAs interrupted at 200Å intervals with a 40 s P2 flux reveal substantial, growth-temperature-dependent incorporation of phosphorus with nanometer-scale lateral variations in interface structure. STM images of InGaAs/InP multiple quantum well structures grown by LP-MOVPE show evidence of interface asymmetry and extensive atomic cross-incorporation at the interfaces. Data obtained by STM have been corroborated by high-resolution x-ray diffraction and reflection high-energy electron diffraction. Together, these studies provide direct information about nanometer-scale grading and lateral nonuniformity of arsenide/phosphide interfaces that can occur under these growth conditions.  相似文献   
17.
Magnetic skyrmions are topologically nontrivial spin structures, and their existence in ferromagnetically coupled multilayers has been widely reported with a disordered arrangement. Here, a nucleation scenario of ordered skyrmions in nanostructured synthetic antiferromagnetic (SAF) multilayers is proposed and experimentally demonstrated using direct magnetization imaging, indirect magnetometer and magnetoresistance measurement, and micromagnetic simulation. Instead of relying on Dzyaloshinskii–Moriya interaction, the antiferromagnetic interlayer exchange coupling in the SAF multilayers fulfills the role of nucleation and stabilization of skyrmions. The robustness of the proposed skyrmion nucleation scenario is examined against temperature from 4.5 to 300 K and device size from 400 to 1200 nm. Interestingly, these synthetic skyrmions still behave well with a size less than 100 nm. The higher stability than generic magnetic domains can be attributed to topological protection. The results thus provide an artificial skyrmion platform to meet the functional needs of high density and designable arrangement in magnonic and spintronic applications.  相似文献   
18.
The restriction fragment length polymorphisms (RFLPs) of 64 random and potentially related strains of Listeria monocytogenes were analysed and compared using a probe comprised of two L. monocytogenes chromosome fragments cloned into a lambda vector. Twelve RFLP types were defined using 14 isolates of clinical origin, 42 food isolates and eight food associated environmental strains. Of the RFLP types, some were common to a particular serovar and source, whereas others were widespread amongst all serovars and sources. One of the two most common RFLP patterns was associated with serovar 1/2 isolates from food or the environment, whereas another dominant pattern was associated most commonly with serovar four isolates from all sources. The potential relationships between epidemiologically related strains were examined, with the analysis of types from a suspected listeriosis outbreak, from clinical maternal-foetal cases, and from an ice-cream factory environmental study. Serotyping alone was not a sufficient marker for the comparison of these strains whereas further discrimination of strains was possible with RFLP analysis.  相似文献   
19.
The aim of the present experiments was to determine the role of insulin and glucagon in the regulation of basal glucose production in dogs fasted overnight. A deficiency of either or both pancreatic hormones was achieved by infusin somatostatin (1 mug/kg per min), a potent inhibitor of both insulin and glucagon secretion, alone or in combination with intraportal replacement infusions of either pancreatic hormone. Infusion of somatostatin alone caused the arterial levels of insulin and glucagon to drop rapidly by 72+/-6 and 81+/-8%, respectively. Intraportal infusion of insulin and glucagon at rates of 400 muU/kg per min and 1 ng/kg per min, respectively, resulted in the maintenance of the basal levels of each hormone. Glucose production was measured using tracer (primed constant infusion of [3-3H]glucose) and arteriovenous difference techniques. Isolated glucagon deficiency resulted in a 35+/-5% (P less than 0.05) rapid and sustained decrease in glucose production which was abolished upon restoration of the plasma glucagon level. Isolated insulin deficiency resulted in a 52+/-16% (P less than 0.01) increase in the rate of glucose production which was abolished when the insulin level was restored. Somatostatin had no effect on glucose production when the changes in the pancreatic hormone levels which it normally induces were prevented by simultaneous intraportal infusion of both insulin and glucagon. In conclusion, in the anesthetized dog fasted overnight; (a) basal glucagon is responsible for at least one-third of basal glucose production, (b) basal insulin prevents the increased glucose production which would result from the unrestrained action of glucagon, and (c) somatostatin has no acute effects on glucose turnover other than those it induces through perturbation of pancreatic hormone secretion. This study indicates that the opposing actions of the two pancreatic hormones are important in the regulation of basal glucose production in the postabsorptive state.  相似文献   
20.
Anatomic correction of transposition of the great vessels   总被引:1,自引:0,他引:1  
We present a new approach for anatomic correction of transposition of the great arteries. The two coronary arteries, with a piece of the aortic wall attached, are transposed to the posterior artery. The two aortic openings are closed with a patch. The aorta and pulmonary artery are transected, contraposed, ant then anastomosed. The interventricular septal defect is closed with a patch, through a right ventriculotomy approach, because the right ventricle is no longer part of the systemic circulation. Two patients, aged 3 months and 40 days weighing 4,200 and 3,700 grams, respectively, were operated upon with deep hypothermia and total circulatory arrest. There was good recovery from the operation, with normal cardiocirculatory conditions. Renal failure developed in the first patient, and she died on the third postoperative day. During this time the cardiocirculatory conditions were good. The second patient made an uneventful recovery. Hemodynamic studies 20 days after the operation showed complete correction of the malformation. Five and one-half months after the operation, he weighs 7,500 grams, and his development is very good. We believe that this operation will be reproducible by most cardiovascular septal defect and pulmonary hypertension.  相似文献   
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