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1.
This article reports a secondary analysis of past therapy outcome meta-analysis. Fifteen meta-analysis provided effect sizes from 56 studies in previous reviews that met 1 of 3 increasingly stringent levels of criteria for clinical representativeness. The effect sizes were synthesized and compared with results from the original meta-analyses. Effect sizes from more clinically representative studies are the same size at all 3 criteria levels as in past meta-analyses. Almost no studies exist that meet the most stringent level of criteria. Results are interpreted cautiously because of controversy about what criteria best capture the notion of clinical representativeness, because so few experiments have tested therapy in clinical conditions, and because other models for exploring the generalizability of therapy outcome research to clinical conditions might yield different results.  相似文献   

2.
In humans, the light peak/dark trough ratio (L/D ratio or Arden ratio) of the electrooculogram (EOG) is conventionally used as an index to estimate the function of the retinal pigment epithelium, but it is rarely in animals. We obtained stable EOG recording in the cat under general anesthesia during light and dark adaptations by applying mechanical forced duction of approximately 3.0 mm in width to one eye of an animal. In five animals, voltages of the dark baseline, the light peak, and dark trough were 580-1,800 (mean, 1,312 microV), 825-2,660 microV (mean, 1,881 microV) and 415-1,480 microV (mean, 1,030 microV), respectively. The L/D ratio in the five animals was 1.70-1.99 (mean, 1.83), similar to that in humans. The present results suggest that the EOG recording by forced duction in experimental animals can be developed into another method to evaluate the retinal pigment epithelial function, particularly to evaluate its potential disorder induced by fluoroquinolones.  相似文献   

3.
On applying p-Nitrocatechinsulphate (2-Hydroxy-5-nitrophenylsulphate) as substrate, characteristic positivity was demonstrable in the pineal gland. The reaction was localized to the Golgi system and to the smooth endoplasmic reticulum, producing in them a homogenous, in the primary lysosomes a fine granulated strongly electron scattering precipitate. The development of primary lysosomes was well detectable with histochemical reaction at the level of both the Golgi apparate and smooth endoplasmic reticulum. Membrane limited bodies occurring in the cells corresponded to autolysosomes. Negative reaction was obtained with para-nitro-phenylsulphate and acethyl-phenylsulphate. The presence of KCN and pCMB inhibited the reaction.  相似文献   

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The whole cell ultrastructure during cell division and morphogenesis of Arthrobacter crystallopoietes was monitored using electron microscopic techniques. Glucose-grown spherical cells were inoculated into succinate-based medium. In this medium, the organism undergoes a morphogenetic cycle consisting of elongation of spheres to rods, exponential growth as rods, and fragmentation of rods to spherical cells. Raised bands or rings that encircled the cells were evident on the cell surface of both sphere- and rod-shaped cells. Many rod-shaped cells possessed two or more rings arranged adjacent to each other in a parallel orientation. At each cell division a new ring was formed on both siblings. However, as predicted by the proposed model of unidirectional cell growth and by maintaining a ring from the previous generation, unequal numbers of rings were observed on sibling cells. Only one ring was visible on most of the spherical inoculum cells, but in some cases a second ring perpendicular to the other ring was observed. Parallel rings were found on spherical cells resulting from fragmentation or reductive cell division of rods during the stationary growth phase. Thus, these spheres could be distinguished from inoculum spheres containing a single ring or perpendicular orientation of rings. The number of rings per cell and arrangement of rings on the cell surface of sibling cells after cell division, but before cell separation, are discussed with respect to cell age, cell division, and sphere-rod-sphere morphogenesis of A. crystallopoietes.  相似文献   

6.
The postnatal differentiation of acinar cells in rat submandibular gland was studied by staining with periodic acid-thiosemicarbazide-silver proteinate to identify carbohydrate-containing macromolecules in the electron microscope. This method revealed glycogen particles and internal substructure in the secretory granules of developing acinar cells. On the basis of morphologic and histochemical criteria three phases of acinar cell development were defined. In the pro-acinar phase, during the first week after birth, pro-acinar cells and terminal tubular cells were the main components of the terminal tubules in the rudimentary gland. The secretory granules of the pro-acinar cells contained speckled or rod-like substructures which stained intensively for carbohydrates and were digested by proteolytic enzymes. During the second to third week after birth, which is the immature-acinar-cell phase, thread-like substructures were seen in the secretory granules. These structures, which were not digested by proteolytic enzymes, disappeared gradually. The acinar cells of 4-week-old or older rats displayed no particular substructure in the secretion granules and represented the final, mature phase of development.  相似文献   

7.
A study was made of the effect of morphine on electrical activity within single ganglia of Auerbach's plexus of guinea pig longitudinal muscle-myenteric plexus as monitored by means of external electrodes. Morphine produces a concentration dependent block of single spike activity. This effect is competitively antagonized by naloxone. The ED50 for morphine effect is about 7 X 10(-7) M. Naloxone and dextrorphan have no effect on electrical activity. Acetylcholine in the concentration range of 10(-7)--10(-5) M augments electrical activity of ganglia. Morphine has little if any effect on the enhanced stimulation produced by acetylcholine thus indicating that the drug does not act directly upon the ganglion. Our results suggest that a specific opiate receptor is present on the preganglionic nerve terminals and that morphine and other opiates block ganglionic transmission by inhibiting the release of preganglionic acetylcholine.  相似文献   

8.
The development of the seminiferous tubule in the first year of life was studied with the electron microscope in five biopsies of normal testes. When HCG stimulation ceases, the fetal Sertoli cell changes into the Sa-Sertoli cell. The possibility of the fetal Sertoli cell having a hormone producing role is discussed. Gonocytes can be detected until the third month post natum. In addition to the gonocytes fetal, transitional, Ap and Ad spermatogonia are also present in the first year of life.  相似文献   

9.
Electron microscopic observations have been made onθ-phase Ni-Mn martensites which form in nearly stoichiometric Ni-Mn alloys. Three fundamental variant-variant pairs, the “A/B”, “A/C”, and “A/D” types, have been identified as well as other combinations of variants with the aid of crystallographic information given by the phenomenological theory of martensitic transformations. The complex mixing of variants, the abundant presence of dislocations, and the large twinning shear have been pointed out as main crystallographic factors hindering the shape-memory-type deformation in this alloy system, in addition to weak grain boundaries. A new grouping of martensite variants is suggested which as a group cancels the shape strain as well as that found in the normal fundamental plate groups. The new grouping also gives the proper combination of variants for which the intersection becomes a single crystal. Formerly with University of Illinois.  相似文献   

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11.
The authors have made an analysis of 1500 operations using a unique technology of closure without perfusion of the interventricular septum defects of the heart under conditions of hypothermia. Lethality was 1.7%, frequency of recanalization of the defects was 0.9%.  相似文献   

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The martensites of titanium binary alloys, containing 1, 2, and 5.3 wt pct Cu, were studied by transmission electron microscopy techniques. Roughly parallel plates with different variants of the orientation relationship, as well as colonies of identical variant plates, prevail in the structures. A stereographic projection analysis of super-imposed diffraction patterns from two adjacent plates is shown to be sufficient for the deduction of the orientation relationship that existed during transformation, which is found to be the Burgers’ relationship -(110)β∥ (0001)α′; 〈111〉β∥ 〈2110〉α′. A graphical method was developed for the derivation of the habit plane and its particular variant, in spite of the absence of retained β phase in quenched Ti-Cu alloys. The habit plane of Ti-Cu martensite is found to be (1079)β with 4 deg accuracy, and to best agree with Class A (α- ω+) solution of the Bowles and Mackenzie theory, rather than with (α+ ω+) or with Class B solutions.  相似文献   

14.
A new 'tissue-stamp culture' method was developed for stamping proliferating erythroblasts of mouse spleens on collagen-coated coverslips after inducing haemolytic anaemia by administration of 1-acetyl-2-phenylhydrazine, and then adherent splenic cells were cultured for a few days. We could obtain many erythroblastic islands, where cultured erythroblasts were located over macrophages and were proliferated synchronously for 10-30 h, and then the erythroblasts were differentiated and enucleated after 30-50 h in the presence of erythropoietin. To observe three-dimensional structures of the erythroblastic islands, a scanning electron microscope was used for the cultured cells treated with critical point-drying method. Immature wrinkled erythroblasts with many micropinocytic pits were attached to the central area of the flattened macrophages with many cytoplasmic projections, though matured erythroblasts were localized on their peripheral areas. Moreover, cytoplasmic projections of underlying macrophages, which were attached to the matured erythroblasts, were decreased in number. At a late stage, deep cytoplasmic invaginations of erythroblasts observed at a middle stage became shallow after their enucleation and flattened to form their concave shapes. This 'tissue-stamp culture' system would be useful for studying specific interaction between stromal macrophages and haematopoietic cells.  相似文献   

15.
Isolated olfactory neuroepithelium and neighbouring respiratory epithelium of 6 Wistar rats after exposure to high frequency irradiation (the microwave carrier frequency was 0.9 GHz; the rectangular pulse modulation was 16 pulses per second; the pulse duration was 50%; the microwave power density in exposure glass chamber was 15 W/kg; the exposure time was 15 min) were studied using high resolution transmission electron microscopy. Ultrathin sections of both epithelia showed the drastic changes in ultrastructure of mucosa. Knobs of primary olfactory neurons and apical parts of supporting (sustacle) cells of the neuroepithelium showed strong vacuolization due to stimulating effect of the microwave irradiation on mucus secretion. The fusion of neighbouring cilia of respiratory cells was revealed. Such "giant cilia" contained more than 5-10 axonemes with basal bodies. In one case the mucus contained paracrystalline structures which were formed by microvilli and nonidentified filamentous protein (10 nm in dia). Degeneration of primary olfactory neuron axons was revealed.  相似文献   

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In the present study we examined if, among other mechanisms, the abnormal exposure of phosphatidylserine at the surface of sickle red blood cells (RBCs) contributes to the hypercoagulability which characterizes homozygous sickle cell disease (SCD). The question was addressed by comparison of the procoagulant properties of RBCs from subjects with various phenotypes (SS, SC and AS) that differ in clinical presentation. As previously reported, SS-RBCs accelerated the prothrombin activation by factor Xa, by decreasing the Km of the reaction compared to normal RBCs. SC-RBCs and AS-RBCs also promoted prothrombin activation although their procoagulant properties were milder compared to SS-RBCs. A significant increase of the thrombin-antithrombin complexes was observed in SS subjects. Prothrombin fragment 1+2 (F1+2) was elevated in half of the SS subjects, but the difference with controls did not reach significance. Elevated levels of thrombin-antithrombin complexes were observed in a number of SC (4/11) and AS (3/12) subjects, but the difference with controls was not significant. A significant correlation was observed between the plasma levels of thrombin-antithrombin complexes in the subjects with SS, AS and AA phenotypes, and the procoagulant properties of RBCs. Our results strongly suggest that the procoagulant properties which characterize SS-RBCs also affect SC-RBCs and AS-RBCs, and that exposure of phosphatidylserine by RBCs contributes to the hypercoagulable state observed in SCD.  相似文献   

18.
Studies of the influence of contrycal on condition of the enzyme systems of the muscles, liver, kidneys and heart of rats with developing granulation tissue showed contrycal, a protease inhibitor, to have a stimulating effect on the LDH and MDH activity and on their isozyme spectrum. The effect of the inhibitor was expressed in the changes occurring in the state of the enzyme system, both at the site of damage (granulations and the underlying tissue) and in a number of internal organs -- the liver and kidneys.  相似文献   

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20.
Neutrophilic urticaria (NU) is a histologically defined entity, but its clinical and pathogenetic aspects are poorly understood. We investigated 22 NU patients whom we identified by examining 118 biopsies of weals. The patients comprised 11 of 20 with acute urticaria, nine of 49 with chronic urticaria, one of 10 with cold urticaria and one of 10 controls undergoing prick tests. Clinically, NU patients had a shorter mean duration of disease than other urticaria patients and significantly increased erythrocyte sedimentation rate and leucocytosis. Histologically, not only neutrophil counts, but to a lesser extent also eosinophil counts and mononuclear cell infiltrates were significantly increased in lesional skin of NU, and there was more marked vasodilatation and endothelial swelling. On immunohistochemistry, increased tumour necrosis factor alpha and interleukin (IL)-3 expression was noted, compared with other urticarias, whereas IL-8 expression was only minor. These data characterize NU as an acute phase urticarial reaction associated with an intense inflammatory infiltrate and marked upregulation of some mast cell-derived cytokines.  相似文献   

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