Ultrastructural imaging of freeze-fractured plant cells in the scanning electron microscope.

The application of the freeze-fracture and cytoplasmic maceration technique in ultrastructural studies of plant cells is described. A major advantage of the technique is, that by extracting mobile cytoplasmic components from the freeze-fractured cells, surface relief is introduced and three-dimensional information is obtainable. The details of specimen preparation are described and the results obtained are reviewed. The use of chitosan embedding for very small or fragile specimens is described.

Ultrastructural organization of two tapetal types in angiosperms.

The development of preparation techniques that include freeze fracturing provide an ideal method for studying the differentiation of plant tissues in the scanning electron microscope. This is illustrated with reference to tapetal development in Catananche caerulea, which has a plasmodial tapetum, and in Lolium perenne, which has a secretory tapetum.

A hypnotic protocol for eliciting physical changes through suggestions of biochemical responses.

We employed brief hypnotherapy to effect physical changes in patients suffering from medical disorders including allergies, rectal bleeding, systemic lupus, hyperemesis, headache, asthma, and chronic pain. We present, in language appropriate to the individual patient, considerations and suggestions to effect the release of healing biochemicals. Ideomotor signals indicated the patient's awareness of the healing. We hypothesize that the technique triggered novel state-dependent memory, learning and behavior.

Identification of a C3b/iC3 binding protein of rabbit platelets and leukocytes. A CR1-like candidate for the immune adherence receptor.

Immune adherence is the attachment of C-bearing immune complexes via the major activation fragment of the third component of C(C3b) to C3b binding membrane proteins. On primate E, the C3b-R, termed CR1, mediates immune adherence. In nonprimates, immune adherence involves platelets instead of E. However, these functional data have not been corroborated by the identification of the binding protein. In this work, we have identified a C3b/iC3 binding protein of rabbit platelets and characterized it as a single chain structure with a Mr of 150 kDa (nonreducing) or 175 kDa (reducing). This protein binds to rabbit iC3 or C3b but not C3d. This specificity of binding and the ability to rebind to a second column of iC3- or C3b-thiol-Sepharose are comparable to human CR1. Also, a molecule with the identical Mr as well as other structural and binding characteristics is present on rabbit PBMC. No such protein was isolated from rabbit E. Our data strongly suggest that the C3b/iC3 binding protein of rabbit platelets is the homologue of human CR1. If so, this represents an interesting evolutionary switch in the tissue specific expression of the immune adherence R from platelets in the nonprimate to E in the primate.

Patient/family education for the patient with a pressure necrosis.

In conclusion, it has been the purpose of this article to discuss patient, family, or significant other teaching for the patient with a pressure necrosis. Teaching content has been presented in tabular form, and the reader has reviewed a number of principles related to learning. Although we have seen that the nurse has certain motives for providing a patient education program, it is the learner who takes the responsibility for using available resources to acquire new knowledge leading to a behavioral skill. Finally, one must recognize that the problem of pressure necrosis care remains one of the most complex and challenging areas to be found in nursing. It is vital to remember that, although difficult, this is a hopefully preventable, treatable, and solvable management problem.

Induction of bladder cancer in rats by fractionated intravesicular doses of N-methyl-N-nitrosourea.

Experiments were conducted to determine the dose response of rat bladder urothelium to a range of different single and fractionated intravesicular doses of the carcinogen, N-methyl-N-nitrosourea (MNU). A dose-related response of bladder-tumour incidence to single graded doses of MNU was found, and a threshold does suitable for use of multistage carcinogenesis experiments was derived from these data. For any given total dose of MNU, the tumour incidence was greater if the MNU had been administered in several small fractions than if it had been administered in fewer larger ones. Extending the interval between doses did not reduce the tumour incidence. It is argued that these results support the multistage theory of carcinogenesis. The histopathology and cell-surface alterations which characterize the development of MNU-induced bladder cancer are described and the contribution of hyperplasia and calculi are discussed.