Search PubMed⌕ Search

Biomedical subjects

G Werner

Publications and source records attributed to G Werner.

At least 91 records · Page 5Linked to original sources
PubMed1988

Zoo medics.

Explore the source record for details and available documents.

Animals↗
PubMed1988

Acrosome formation during spermiogenesis in Notonecta glauca L. (Heteroptera).

The giant spermatozoon of Notonecta glauca has a 1 mm long acrosome. It has the shape of a stiff needle with round cross section and contains several different components. Morphogenesis of this simple form proceeds by very complex changes of both the internal structure and the outer shape. Surrounded by a great number of individual dictyosomes the acrosome is attached to the anterior nuclear pole where it grows to a sphere measuring about 20 microns in diameter. In its interior differentiations consisting of several components become visible which develop independently and may be characterized as basal and lateral complexes. At the end of the growing phase these two complexes come in contact with each other. After the dictyosomes have detached from the acrosome, the cell membrane surrounds the acrosome very closely so that cytoplasmic structures temporarily disappear completely from the narrow space in between. The tip of the acrosome grows out of the sphere as a slender lateral process which becomes increasingly spiralized. It shows a deep lateral groove, its contents consist of components of the basal complex. Parts of the lateral complex form a baso-lateral protuberance. Between these two structures a narrow channel extends from the subacrosomal space to the base of the lateral process. During elongation the acrosome attains spindle shape, the lateral process gradually becoming its anterior part. The distance between acrosome and cell membrane broadens again and cytoplasmic structures reappear among them about 1000 microtubules which are not surrounded by a sleeve membrane. In the posterior part cell membrane and acrosomal membrane are connected by two lines of weld spots where acrosomal membrane is eliminated as small vesicles. In the anterior part the groove becomes deeper. One leg of its initially U-shaped cross section becomes longer and is wrapped around the shorter one. The two legs subsequently fuse with the consequence that membrane and cytoplasmic components of the former groove become secondarily incorporated into the acrosome. The subacrosomal channel obliterates and the cross section of the acrosome showing acute angles in later stages finally gets round. Anterior and posterior part of the acrosome can be differentiated due to structural details even in the mature sperm.

Acrosome↗
PubMed1987

Methuselah--an expert system for diagnosis in geriatric psychiatry.

This report is based on the notion that criteria for "successful" diagnosis differ for different medical specialties. Diagnostic judgement in highly unstructured task domains is best characterized as clinical problem formulation with pragmatic implications for interventions. This concept is illustrated by the implementation of a computer-based diagnostic expert system for geriatric psychiatry. The program begins with guiding the patient's interview by the clinician. This is followed by the diagnostic process which is conducted in three steps. In the first step, candidate syndromes of disease states are identified by matching the presenting complaints with symptom lists of clinical syndromes. In the second step, the candidate syndromes serve as the organizers for gathering additional patient data (e.g., information from referral source and past illnesses) to seek constellations of findings which form a coherent clinical context. In this phase, the program can also prompt the clinician to obtain additional information from the patient or other available sources to resolve conflicts or, if necessary, invoke the concurrent presence of two independent syndromes to attain convergence (i.e., minimize the number of unexplained findings). In a final step, the syndromes with highest credence value, reflected by the number of linkages to patient data, are sharpened to specific diagnostic formulations. This is accomplished by frames of diagnoses which are associated with each syndrome. Once again, the patient data can be consulted to achieve optimal matches. A summary statement to the clinician lists the essential supporting evidence for the chosen diagnosis and can communicate alternatives or unresolved issues for clarifying interventions. Although no decisive evidence is available, informal observations of clinicians support the notion that clinical reasoning in highly unstructured domains is largely contextual and seeks apprehension of "gestalts" in successive steps. The diagnostic program of this report aims at simulating this process.

Aged↗
PubMed1986

Psychiatric decision making in family practice. Future research directions.

Psychiatric illnesses in family practice are significantly underdiagnosed because of factors associated with both the physician and patient. Clinicians too often fail to utilize a biopsychosocial approach in the assessment process, tending to assess symptoms as organic regardless of their etiology. Patients similarly tend to emphasize the physical nature of their complaints when presenting in medical settings. Efforts have been made to improve the physician's diagnostic accuracy through the use of screening scores. The results, however, are inconclusive. It remains unclear whether the physician disregards this information or considers it irrelevant. We suggest that future research investigate not only the accuracy of the clinician's diagnostic formulation but also the processes whereby the family practitioner elicits, analyzes, and synthesizes or discards cues pertinent to mental illness. By combining statistical analyses with the analytic techniques developed in studies of medical decision making and general problem solving, detailed leads should emerge for the design of improved didactic and experiential training programs.

Attitude of Health Personnel↗
PubMed1986

Molecular cloning and sequence determination of the genomic regions encoding protease and genome-linked protein of three picornaviruses.

To investigate the degree of similarity between picornavirus proteases, we cloned the genomic cDNAs of an enterovirus, echovirus 9 (strain Barty), and two rhinoviruses, serotypes 1A and 14LP, and determined the nucleotide sequence of the region which, by analogy to poliovirus, encodes the protease. The nucleotide sequence of the region encoding the genome-linked protein VPg, immediately adjacent to the protease, was also determined. Comparison of nucleotide and deduced amino acid sequences with other available picornavirus sequences showed remarkable homology in proteases and among VPgs. Three highly conserved peptide regions were identified in the protease; one of these is specific for human picornaviruses and has no obvious counterpart in encephalomyocarditis virus, foot-and-mouth disease virus, or cowpea mosaic virus proteases. Within the other two peptide regions two conserved amino acids, Cys 147 and His 161, could be the reactive residues of the active site. We used a statistical method to predict certain features of the secondary structures, such as alpha helices, beta sheets, and turns, and found many of these conformations to be conserved. The hydropathy profiles of the compared proteases were also strikingly similar. Thus, the proteases of human picornaviruses very probably have a similar three-dimensional structure.

Amino Acid Sequence↗
PubMed1986

[Appendicitis in the aged].

Peculiarities relating to appendicitis in advanced age are described in this paper, with reference being made to a prospective study conducted in 1982 into acute abdominal processes. Covered by that study were 545 patients with acute abdominal symptoms. Reference was also made to an evacuation of 890 cases of appendectomy performed between 1983 and 1985. Appendicitis was found to be relatively rare in advanced age and accounted for merely seven per cent of all appendectomies. Frequent reports on increased perforation rates in advanced age were confirmed by the authors' own findings. Presurgical diagnostic accuracy was between 70 and 75 per cent, relative to the surgeon's visual intra-operative findings. The assumption has to be made that in 25 to 30 per cent of all appendectomies the vermiform appendix processus is removed without detection of any acute inflammation. In patients in advanced age, particular attention should be given to renal and urinary tract findings with complaints that might encourage falsely positive indications for laparotomy.

Aged↗
PubMed1985

[Damage caused by ionizing radiation/acute radiation sickness].

The article deals with the diagnostics, differential diagnostics and therapy of the acute radiation syndrome at a possible war. Decisive points of view are, taking into consideration the clinical course, simplified diagnostic methods and gradually coordinated therapeutic methods when there is a widespread occurrence of injured persons. The treatment in the base with appropriate medical evacuation is the basis. The synoptic paper summarizes the newest realizations.

Combined Modality Therapy↗
PubMed1985

[Responsibilities and tasks of internal military medicine].

Issuing from several historical facts, object and tasks of internal military medicine are explained in a synoptic report. As a result of the revolution in military affairs this still relatively young subject of military medicine developed. In this article the object and special problems of this interdisciplinary field, such as treatment in the base and the medical evacuation are analysed. The explanation of methods and techniques concerning the medical aid in injured persons of internal profile is the main topic of the paper.

Delivery of Health Care↗