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1.
Variations in localization of the central sulcus and the sulci around the central sulcus namely the superior frontal sulcus, precentral sulcus, postcentral sulcus, marginal ramus of cingulate sulcus were studied in vertex sections retrospectively by magnetic resonance imaging (MRI) method in 3580 cases. Out of total number of cases, 1000 who did not show any macroscopic intracranial pathology were carefully selected for research. Additionally, 0-1 age group was excluded from the study because the sulci develop in first year of postnatal life, excluding the possibility of considering these as anatomical variations. Thus, the total number of cases is decreased to 990. 16 variations related to localization of the superior frontal sulcus, precentral sulcus, central sulcus, postcentral sulcus and the marginal ramus of the cingulate sulcus were identified. The asymmetries of the sulci, the most variable sulci and the distribution of the variations according to sex were statistically analysed.  相似文献   

2.
The purpose of this study was to determine the relationship between sarcoma tumor grade and the quantitative tumor metabolism value for [F-18]fluorodeoxyglucose (FDG) determined by positron emission tomography (PET) imaging. Seventy patients with bone or soft-tissue sarcomas underwent PET scanning with quantitative determination of tumor FDG metabolic rate (MRFDG) before treatment. MRFDG (micromol/g/min) for each tumor was compared with National Cancer Institute tumor grade, S-phase percentage, and percentage of aneuploidy of the tumor population. The pretreatment quantitative determination of tumor MRFDG by PET correlates strongly with tumor grade but not with the other selected histopathological tumor correlates. In addition, overlap of MRFDG PET values with tumor grade suggests that PET, an objective tumor measurement, may provide an alternative means of assessing tumor biological potential or may have the potential to overcome some of the limitations of traditional pathological evaluation. FDG PET can uniquely provide a metabolic profile of a diverse group of sarcomas noninvasively and provide clinically relevant tumor biological information.  相似文献   

3.
The development of the early stage of locomotion (between Postnatal Days 3 and 10) was studied in newborn rats. At this age, rats are known to perform limited locomotor activities, consisting of an inefficient nonpostural gait termed crawling. By providing appropriate olfactory stimulation, it was possible to override the pups' reluctance to walk and to discover their actual locomotor abilities. The step period decreased from 1,200 ms to 900 ms from Postnatal Days 4 to 9, showing both a regular decrease in the swing and a discontinuous decrease in the stance phase. The fore- and hindlimb periods stabilized early on an alternate pattern of coupling. The ipsilateral coupling shifted progressively from 220 degrees to 260 degrees in relation with the change in the gait pattern. In parallel with the change in timing, the newborn rats showed gradual changes in the foot position and in the interlimb spatial coordination. These results show that quadruped locomotion develops before postural control is acquired, in a continuous process as the nervous system develops.  相似文献   

4.
The authors compute a diagnostic (Di) and a prognostic (Pi) index in primary open angle glaucoma. Four groups of patients were studied. Group A consisted of subjects under 50 years of age, group B of subjects over 50 years of age, group C of patients with normal tension glaucoma and group D with high tension glaucoma. All patients underwent color doppler imaging of the ophthalmic, posterior ciliary and choroid arteries. The Di of the choroid vessels were 0.967 +/- 0.011 (gp. A), 1.112 +/- 0.010 (gp. B), 1.506 +/- 0.008 (gp. C) and 2.891 +/- 0.083 (gp. D). The Pi of the posterior ciliary arteries were 22.700 +/- 1.160 (gp. A), 20.000 +/- 0.943 (gp. B), 15.100 +/- 0.568 (gp. C) and 12.100 +/- 0.083 (gp. D). Confirmation of these data might validate them as a tool for preventing the evolution of glaucomatous optic neuropathy.  相似文献   

5.
Variations in the anatomic course of the cutaneous nerves about the lateral aspect of the elbow are important when surgical exposures and the establishment of arthroscopic portals are considered. The specific anatomic course taken by the lateral antebrachial cutaneous nerve and its relationship to the lateral epicondyle were determined by studying 33 upper extremities in 22 preserved adult cadavers. Considerable anatomic variation was found regarding the location of the lateral antebrachial cutaneous nerve as it crossed the elbow. The nerve pierced the brachial fascia an average of 3.2 cm proximal to the lateral epicondyle and was located an average of 4.5 cm medial to the lateral epicondyle as it crossed the interepicondylar line. In two instances, the nerve passed through the biceps muscle directly, prior to piercing the brachial fascia.  相似文献   

6.
7.
BACKGROUND: We believe rigid plate fixation may be superior to wire fixation in sternal closure, as rigid fixation used in the craniofacial skeleton has shown greater stability, lower postoperative pain, and accelerated bone healing. We hypothesize that sterna fixed with titanium plates are more stable mechanically than sterna fixed with wires. METHODS: The sterna from human cadavers were used in this two-phased study. Phase I compared wires to four-hole titanium straight plates. Phase II compared wires to four-hole titanium custom H plates. The sterna were tested biomechanically using all fixation methods. RESULTS: Phase I showed no statistically significant difference in the stiffness or lateral displacement between the wired and straight plated sterna. Phase II showed a statistically significant greater stiffness (p < 0.05) and less lateral displacement (p < 0.05) in the custom plated sterna over the wired sterna. CONCLUSIONS: Our results showed that custom titanium H plates were superior to wire fixation. Furthermore, our results established the importance of plate configuration in sternal fixation. Our study may have beneficial clinical implications, as decreased motion at the sternotomy site could mean less postoperative pain, a decreased incidence of infection, and accelerated bone healing.  相似文献   

8.
A versatile modular hip system was used to evaluate the initial stability of a cementless femoral stem in anatomically consistent composite bones. Four implant bone configurations of varying proximal and distal fit/fill were tested. The implanted femurs were tested on an Instron 1331 materials testing machine in neutral loading and flexion loading; both translational micromotions and rotations of the implant relative to the bone were recorded on all three axes of motion, accounting for all 6 degrees of freedom of joint motion. Implants were then sectioned, and both endosteal canal fit and intramedullary canal fill were measured. Results indicate that (1) loading the implant in flexion by out-of-plane forces significantly increases both relative translation and rotation at the interface, (2) increasing the proximal fit reduces implant rotation about its longitudinal axis in flexion loading and (3) increasing the distal canal fit and fill increases prosthesis rotation about its longitudinal axis in flexion loading. These results indicate that the femoral stem is more unstable in out-of-plane loading, such as during stair climbing, and that increasing the proximal fit may enhance the initial rotational stability of an uncemented femoral stem.  相似文献   

9.
The osmotic responses of isolated human islets were evaluated using a perfusion cryomicroscope device. Individual islet volumes were measured following equilibration with a series of solutions of graded solute concentration. The osmotically inactive volume for human islets was determined to be 25% from a Boyle-van't Hoff plot of these data. A network thermodynamic model was developed via the bond graph method to describe the transport of water and cryoprotective agent in pancreatic islets. The model was curve fit to transient volumetric data for the response of islets to a stepwise exposure to 1 Me2SO at temperatures of 24.0, 3.0, or -3.5 degrees C. Standard membrane transport parameters (Lp, omega, sigma) and interstitial diffusion transport properties (kappa w, kappa p) were calculated from the fitting procedure. The temperature coefficients for membrane transport properties were expressed in terms of activation energies for water (ELp) and Me2SO (E omega). Osmotic challenge experiments conducted with fresh and cryopreserved human islets indicate that frozen/thawed islets exhibit a a slight increase in transport properties.  相似文献   

10.
Diffuse bleeding from parenchymatous organs at conventional surgery is eliminated with the usual methods coagulation tamponade or styches. We performed experimental series at 9 dogs. After resection of spleen, liver, pancreas and kidney, the bleeding surface was covered by collagen fleece coated with fibrin glue (TachoComb). Postoperatively 7 days, 10 days, 14 days and 28 days we made a relaparotomy. Then the results were analyzed macroscopically and microscopically. In the abdominal cavity neither significant quantity of blood nor greater adhesions were detected. At all cases the fibrin glue was found on place were it was put before. Histologically a perfect wound healing experienced. The fibrin glue (TachoComb) using at diffuse parenchymatous organs' bleeding give a very good results when the wound area is at least 1 cm beyond the immediate wound margin and the fibrin glue is applied onto the wound and pressed on it for 4-5 minutes.  相似文献   

11.
Anterior placement of the femoral tunnel during anterior cruciate ligament reconstruction results in nonisometric placement, and posterior placement can lead to posterior tunnel blow out or troughing. Creating a pretunnel footprint before final placement and drilling allows the surgeon to visually verify that proper femoral tunnel placement has been obtained.  相似文献   

12.
MB Ackerman 《Canadian Metallurgical Quarterly》1997,18(11):1131-8, 1140; quiz 1142
The full coverage restoration (FCR) and its effect on the periodontium have been the subject of much controversy over the last half century. The conflict relates to whether the margin of the FCR should be placed at or above the gingival crest, or into the gingival crevice. Clinicians and researchers alike have focused their attention primarily on the mechanistic aspects of fixed prosthetic design (i.e., marginal configuration and fit). Although marginal quality and form are factors in the fabrication of the FCR, they alone will not determine periodontal health and restorative success. What determines the success of the FCR is its ability to restore form and function to the masticatory system without adversely affecting its biology. Each technical phase of treatment (i.e., tooth preparation, impression-taking, the provisional restoration, and the final restoration) must be performed within the limits of biologic adaptation. This literature review discusses the scientific evidence regarding FCR margin placement and periodontal health.  相似文献   

13.
Higher plant tissues produce both wax esters generated from fatty alcohols and hydrocarbons generated from fatty aldehydes. If two different reductases are responsible for the synthesis of aldehydes and alcohols, both types of reductases may be present in such tissues. To test for this possibility, pea leaves, known to produce both types of wax components, were examined. Subcellular fractionation showed that acyl-CoA reductase activities were localized mainly in the microsomal fraction. Fatty aldehyde formation was rectilinear for 30 min and subsequently decreased, whereas fatty alcohol formation remained linear for 2 h. The two activities in the microsomes were differently affected by pH; alcohol formation was optimal between pH 5 and pH 6, whereas aldehyde formation was optimal at around pH 7.5. With solubilized microsomes, protein concentration dependence of alcohol formation showed a sigmoidal pattern, possibly suggesting inhibition by hexadecanoyl-CoA at low protein concentrations. Bovine serum albumin (BSA) enhanced alcohol formation. In contrast, the aldehyde generation showed a typical protein concentration dependence, and BSA severely inhibited aldehyde generation. Phosphatidylcholine showed over twofold stimulation for alcohol formation, whereas aldehyde formation was only slightly stimulated. All of this biochemical evidence suggested the presence of two different reductases. Confirming this hypothesis, an aldehyde-generating and an alcohol-generating reductase were resolved from the solubilized microsomal proteins using Blue A agarose, gel filtration, and hexadecanoyl-CoA affinity chromatography. SDS-PAGE of the purified proteins showed that the alcohol-generating enzyme was a 58-kDa protein and the aldehyde-forming one was a 28-kDa protein. It is proposed that two different elongating systems are functionally coupled to the alcohol-generating and aldehyde-generating reductases, which in turn are coupled to the transacylase to produce wax esters and to the decarbonylase to produce hydrocarbons, respectively.  相似文献   

14.
BACKGROUND: The adventitial inversion technique obliterates the false lumen and converts a dissected aorta into a conduit with tough adventitia on the inside and outside. Dacron grafts can be anastomosed to the aorta with fine sutures, which hold without tears. METHODS: From August 1995 to March 1997, we treated 6 patients with acute dissecting aneurysms. Three aneurysms were type I (A) involving the entire aorta, two type II (A) involving the ascending aorta, and one type III (B) involving the thoracoabdominal aorta. Circulatory arrest was used in 3 patients, 1 with type I aneurysm (A), 1 type II (A), and 1 type III (B). RESULTS: All Dacron-aorta anastomoses held sutures well and did not bleed intraoperatively or postoperatively. One patient (type II [A]) died of intraoperative low cardiac output. In patients with type I (A) aneurysms, the false lumen was obliterated, but 1 patient required resection of a 6-cm abdominal aortic aneurysm. CONCLUSIONS: The adventitial inversion technique is a safe technique for the treatment of acute dissecting aneurysms, which facilitates operation and solves the problem of intraoperative or postoperative bleeding due to tissue friability.  相似文献   

15.
The Singh index was used to measure the degree of osteoporosis in patients with fracture of the neck of the femur and to compare its prevalence with a random population sample in Jerusalem. The frequency of osteoporosis was 22.7% among women in the fracture series as compared with 1% in the control group. These figures are much lower than those in comparable series. The Singh index was not as sensitive an indicator of spinal osteoporosis as a direct measurement of vertebral bone density and could not be correlated with the incidence of hip fractures.  相似文献   

16.
The complement system covalently attaches C3d to microbial antigens which binds to CR2 on B lymphocytes, leading to a markedly enhanced adaptive immune response to that antigen. The enhancement is mediated by the cross-linking of the CR2-CD19 complex to mIg which augments the activation of several intracellular signalling pathways. Two additional receptors of the B lymphocyte, FcgammaRIIB and CD22, have opposing effects when cross-linked to mIg, the former suppressing signalling by recruiting the inositol phosphatase, SHIP, and the latter by activating the phosphotyrosine phosphatase, SHP-1. Two principles emerge from these studies: innate immunity guides the adaptive immune response, and activation of the B lymphocyte is determined by co-receptors which evaluate the biological characteristics of antigen.  相似文献   

17.
AIM: To assess a newly developed immunohistochemical detection system, the EnVision++. METHODS: A large series of differently processed normal and pathological samples and 53 relevant monoclonal antibodies were chosen. A chessboard titration assay was used to compare the results provided by the EnVision++ system with those of the APAAP, CSA, LSAB, SABC, and ChemMate methods, when applied either manually or in a TechMate 500 immunostainer. RESULTS: With the vast majority of the antibodies, EnVision++ allowed two- to fivefold higher dilutions than the APAAP, LSAB, SABC, and ChemMate techniques, the staining intensity and percentage of expected positive cells being the same. With some critical antibodies (such as the anti-CD5), it turned out to be superior in that it achieved consistently reproducible results with differently fixed or overfixed samples. Only the CSA method, which includes tyramide based enhancement, allowed the same dilutions as the EnVision++ system, and in one instance (with the anti-cyclin D1 antibody) represented the gold standard. CONCLUSIONS: The EnVision++ is an easy to use system, which avoids the possibility of disturbing endogenous biotin and lowers the cost per test by increasing the dilutions of the primary antibodies. Being a two step procedure, it reduces both the assay time and the workload.  相似文献   

18.
The extensor tendons of the fingers and toes form part of the capsule of the interphalangeal joint and press against the proximal phalanx during flexion. Previous work on the fingers has shown that there is a "sesamoid" fibrocartilage on the deep surface of each tendon that labels immunohistochemically for a variety of glycosaminoglycans and collagens. However, we know little about the molecular composition of the tendon in the toes. This question is of special interest, because the mechanics of the interphalangeal joints differ in the upper and lower limbs-the toes balance the forefoot, distribute load during the gait cycle, and transmit the pull of larger muscles. This means that their extensor tendons are more often under higher tension than those in the fingers. Here, we report the presence of an equivalent fibrocartilage and compare its immunolabelling characteristics in all the toes. Six forefeet were removed from elderly cadavers, and the interphalangeal (IP) joints were fixed in 90% methanol. The extensor tendon and its enthesis were dissected out from the IP joint of the big toe and from the proximal interphalangeal (PIP) joint of all lesser toes, decalcified, cryosectioned, and immunolabelled with a panel of monoclonal and polyclonal antibodies for type I, II, III, and VI collagens; chondroitin 4 and 6 sulphates; and dermatan and keratan sulphate. Antibody binding was detected with the Vectastain ABC Elite avidin-biotin-peroxidase kit (Vector Laboratories, Burlingame, CA). The extensor tendon in all the toes had a metachromatic, sesamoid fibrocartilage on its deep surface that immunolabelled for all glycosaminoglycans and for type I, III, and VI collagens. Labelling for type II collagen was seen in the sesamoid fibrocartilage of all toes but was particularly characteristic of the 2nd through 5th toes. The immunolabelling patterns of the enthesis fibrocartilage were similar in all toes and to results reported previously for fingers. The normal occurrence of type II collagen in the sesamoid fibrocartilage of the 2nd through 5th toes is in contrast to our published data on the fingers. The finding can be related to the more constant loading of the tendon in the toes. The greater prominence of type II collagen in the sesamoid fibrocartilage of the 2nd through 5th toes could be related to a difference in joint position during walking between the 1st toe and the 2nd through 5th toes--the PIP joints of the latter are usually more flexed than the IP joint of the former.  相似文献   

19.
We treated two cases of primary pulmonary cryptococcosis with fluconazole (FLCZ), the clinical usefulness of FLCZ was evaluated. FLCZ was administered orally in doses of 300 mg daily for about six months. Concentrations of FLCZ were measured in the serum of the two cases and in the bronchoalveolar lavage (BAL) fluid in one case. The following results were obtained: 1. Clinical cures were obtained in the two cases. 2. The serum levels of FLCZ was 15.1 microliters/ml, 13.6 micrograms/ml two hours after administration of 100 mg in case 1, that of levels were 11.1 micrograms/ml, 8.9 micrograms/ml one hour and 4.5 hours, respectively, after administration of 100 mg in case 2. BAL was performed 4.5 hours after administration of 100 mg in case 2, the BAL fluid level of FLCZ was 0.7 microgram/ml. 3. The minimal inhibitory concentration of FLCZ against one strain obtained from the cytology brush in case 1 was 4.0 micrograms/ml. 4. The cryptococcal antigen titer decreased with the improvement of clinical signs and the resolution of chest X-ray abnormalities within about six months, and there was no relapse. From these results, we consider that FLCZ is a useful antifungal agent for primary pulmonary cryptococcosis, and we therefore recommend a six month treatment.  相似文献   

20.
BACKGROUND: Familial inheritance of slipped capital femoral epiphysis (SCFE) is known. It has not been described in non-identical twins. A family where the mother and three of five siblings developed SCFE were investigated and managed. METHODS: Anthropometric measurement consisted of height-weight ratios. Serum sex hormone levels and bone Gla Protein was measured. Bone mineral densities were evaluated. RESULTS: The affected siblings had higher bodyweight percentiles. Other investigations were within normal limits. CONCLUSION: The unfavourable height-to-weight ratio was one of the mainstays in developing a management protocol for all siblings. The management protocol developed for the family is discussed.  相似文献   

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