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S A Mitchell

Publications and source records attributed to S A Mitchell.

At least 55 records · Page 3Linked to original sources
PubMed1993

Aggression and the endangered self.

Discussions of aggression in the psychoanalytic literature are dominated, both explicitly and implicitly, by loyalty to, or rejection of, Freud's theory of the aggressive drive, which has caused an unfortunate polarization. An approach to aggression is presented that preserves essential features of both drive theory and nondrive theory traditions. It is suggested that this way of thinking about aggression is actually prevalent in both contemporary Freudian and non-Freudian thought without being recognized as such.

Aggression↗
PubMed1992

Antibacterial peptides designed as analogs or hybrids of cecropins and melittin.

Eight new analogs of cecropin A, two new analogs of melittin and 30 hybrid peptides containing sequences from cecropins and melittin have been synthesized. The lengths of the peptides have varied from 37 residues (the length of cecropin A) to 18 residues. The peptides have been assayed for lysis of sheep red blood cells and for antibacterial activity against two Gram negative and three Gram positive bacteria. The best analogs of cecropin A maintained the anti-Escherichia coli activity of the parental peptide, and were not lytic for red blood cells. Melittin and its replacement analogs were all lytic for red blood cells, but an analog with transposed segments was not. Several of the hybrid peptides were found to be both non-hemolytic and highly active against all test bacteria. The data were used to define the structural requirements for antibacterial activity.

Amino Acid Sequence↗
PubMed1990

Acoustic measurements of objective tinnitus.

Ear canal sound pressure levels were measured from a 38-year-old woman who had experienced objective tinnitus in her right ear for approximately 2 years. The tinnitus sounded like a series of "sighs" that were synchronous with her pulse rate. Because the level of the tinnitus fluctuated in a pulsing manner, it appeared to be of vascular origin. Psychoacoustically, the tinnitus behaved like a low-pass masker (cutoff frequency = 1.5 kHz) of about 40 dB SPL. This masking effect was manifested as a low-frequency hearing loss in the subject's right ear. A miniature microphone system was used to monitor the tinnitus before, during, and after a jugular-vein ligation. Because the cause of the tinnitus was only generally known, acoustically monitoring the sound as the jugular vein and/or its tributaries were systematically clamped and then released enabled the site of generation to be known exactly. By monitoring the tinnitus during surgery, the effectiveness of the corrective procedure could be immediately evaluated. Hearing sensitivity in the affected ear returned to normal limits following the elimination of the tinnitus. One year after the surgery, the tinnitus was barely audible to the woman, but only when she positioned her head a specific way. The level of the tinnitus measured in this head-turned condition was markedly lower than the level obtained preoperatively.

Adult↗
PubMed1990

Parvovirus infection and anaemia in a patient with AIDS: case report.

Opportunistic infections such as Pneumocystis carinii pneumonia are well-recognised in patients with the acquired immune deficiency syndrome (AIDS). Anaemia due to a variety of causes also occurs in AIDS. Persistent infection with parvovirus (B19) causing severe anaemia has been reported in patients with leukaemia and congenital immunodeficiency. A case is now reported of parvovirus infection and anaemia, in an adult with AIDS, which responded dramatically to immunoglobulin therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Aetiology of non-gonococcal urethritis: a possible relation to other infections.

Chlamydia trachomatis can be identified in up to 60% of cases of nongonococcal urethritis (NGU) and the aetiology of most of the remainder is obscure. This paper reports a role for other genitourinary (GU) infections such as candidiasis, warts and herpes simplex, in the causation of NGU. One hundred and ten men fulfilled the entry criteria which included the probability that their contacts would attend the department. Fifty-four of the 110 men had GU infections other than NGU; 56 had no other infections. NGU was detected in 31 (57%) of cases with other GU infections and 8 (26%) were chlamydiae-positive: in contrast NGU was found in only 10 (18%) of those with none of the other infections and 3 (30%) were chlamydiae-positive. Chlamydiae-negative NGU was, therefore, more common in those with other GU infections. Forty-five (86%) of 52 contacts of 41 patients with NGU had various GU infections such as candidosis and anaerobic vaginosis, in contrast with other GU infections in only 7 (23%) of 30 contacts of men with no other GU infections. Other GU infections in patients and their contacts appeared significantly related to the presence of chlamydiae-negative NGU.

Adult↗
PubMed1989

A survey to identify deficiencies in transfusion medicine education.

Medical faculty, blood center directors, and technologists were surveyed to assess current opinions of knowledge deficiencies in transfusion medicine among medical school graduates, housestaff, and practicing physicians. Over 90% of those responding believed additional training in transfusion medicine was needed. Nine categories of deficiencies were identified, with more than 40% of respondents' comments reflecting concern about the lack of knowledge of the use of blood and blood components. Clinical faculty and blood bankers differed in their assessments of the knowledge deficiencies in two of the nine categories. Information obtained in this survey is relevant to educational development in transfusion medicine.

Blood Banks↗
PubMed1984

Timing and antecedents of intracranial hemorrhage in the newborn.

Fifty newborn infants of less than 33 weeks' gestation were followed prospectively from birth to evaluate the temporal relationships of various clinical factors to the onset and progression of intracranial hemorrhage (ICH) in an inborn population given maximal support. ICH was diagnosed and followed with bedside ultrasound every eight hours. The incidence of intraventricular hemorrhage was 30% and of any ICH was 40% with onset from less than 2 hours to 8 days of age. Grades 2, 3, and 4 ICH correlated with Apgar scores of less than 5 at five minutes, vaginal delivery, longer labors, and intrapartum hemorrhage. There was a significant correlation between ICH and both blood pressure fluctuations of greater than 100% and rapid colloid infusions. Slow transfusions of packed red cells did not appear to precipitate episodes of ICH. In a setting of optimal care, ICH appears to be more related to prenatal stresses than to specific postnatal complications.

Apgar Score↗
PubMed1978

Psychodynamics, homosexuality, and the question of pathology.

A persistent polarity has existed among theories concerning the origins and the nature of preferred homosexuality. One major group of theories, including most psychoanalytic approaches, stresses early developmental contributions and tends to view homosexuality as psychopathological--a deviation from healthy and fully mature living. The other major group of theories assumes homosexuality not to be psychopathological and views homosexuality as either a spontaneous expression of a natural, polymorphous sexuality, or as one possible outcome, among many equally healthy and rewarding outcomes, of social conditioning. Common to both groups of theories is the shared assumption that psychodynamic contributions and etiology imply pathology--a psychodynamic dimension is either accepted and pathology is assumed, or pathology is denied and any possible psychodynamic contribution is debunked. The notion that psychodynamic causes and contributions imply pathology is, as I will show, a historical artifiact deriving from Freud's original libidinal fixation theory of neurosis. Such an assumption is not only no longer necessary, but also is inconsistent with a more contemporary psychondynamic understanding of human experience and several important psychoanalytic principles. I will explore the manner in which this assumption has been responsible for polarization and miscommunication among various contributions in psychoanalytic, sociological and political literature on the nature of homosexuality--including the presumption of pathology that is built into the very language and choice of metaphors employed in psychoanalytic discussions of homosexuality. I will also suggest an alternative conceptual approach.

Adaptation, Psychological↗