PubMed Health⌕ Search

Biomedical subjects

J K Davidson

Publications and source records attributed to J K Davidson.

At least 19 recordsLinked to original sources
PubMed2000

Porous polyethylene implant fibrovascularization rate is affected by tissue wrapping, agarose coating, and insertion site.

PURPOSE: Often used in facial and ocular reconstruction, biointegratable materials, such as hydroxyapatite and high density porous polyethylene, can be associated with migration, exposure, and infection. Complications are less likely after implants become fibrovascularly integrated. A model was sought to study the influence of multiple factors on the rate of fibrovascular ingrowth into porous implants. METHODS: High density porous polyethylene cubes were implanted into paraspinous skeletal muscles in rabbits. The cubes were explanted at weekly intervals using survival surgery. The number of fibroblasts at the center of each cube was counted, generating a time-dependent standard curve of cell accumulation. Porous polyethylene cubes uncoated, coated with agarose (a plant-derived carbohydrate), or coated with nonperforated sclera (human or rabbit) were implanted into suprascapular adipose and paraspinous skeletal muscle in other rabbits. RESULTS: Fibrovascular ingrowth occurred more rapidly with cube implantation into skeletal muscle versus adipose, with increased surface area contact between implants and muscle, and with removal of muscle capsules. While the rate of fibroblast accumulation decreased in cubes coated with sclera, coating the cubes with agarose increased the fibrous capsule formation without altering the rate of biointegration. CONCLUSIONS: This study provides a novel approach for the study of fibrovascular ingrowth into implants treated under a variety of conditions. Modification of current surgical techniques may increase the rate of porous polyethylene implant biointegration.

Adipose Tissue↗
PubMed1997

Guilt about first intercourse: an antecedent of sexual dissatisfaction among college women.

First sexual intercourse is often viewed as a rite of passage to adulthood. While one's initial coital experience may lead to affirmation of self-identity, it is disappointing for many, resulting in feelings of guilt and shame. If guilt feelings do emerge, the likelihood of future sexual dissatisfaction is greatly increased. In particular, women with high levels of sexual guilt tend to perceive less sexual arousal, resulting in less enjoyment from their sexual encounters. The purposes of this investigation were to identify those factors correlated with feeling guilty about first sexual intercourse and to examine the influence of guilt about first intercourse on current sexual satisfaction. An anonymous questionnaire was administered to never-married college women, with the subsample for this investigation consisting of 570 women. Significant variables correlated with guilt at first sexual intercourse include uncommunicative mother and father figures, overstrict father figure, uncomfortableness with sexuality, physiological and psychological sexual dissatisfaction with first intercourse, guilt feelings about current intercourse, and psychological sexual dissatisfaction. These findings have substantial implications for sex researchers, sex therapists, family therapists, and sexuality educators who wish to promote healthy sexuality, through both attitudes and behavior.

Adolescent↗
PubMed1994

Masturbation and premarital sexual intercourse among college women: making choices for sexual fulfillment.

Given the potential value of masturbation as an alternative to high-risk sexual practices, there is a need to investigate factors surrounding this method of physiological sexual fulfillment. Therefore, this study examined the differences, if any, between women who have engaged in masturbation only (MO), both masturbation and sexual intercourse (MSI), and sexual intercourse only (SIO). An anonymous questionnaire was administered to volunteer respondents enrolled at a Midwestern university, yielding a subsample of 777 never-married, heterosexual women. Group comparisons indicated that MO Group women were most likely to feel guilty about engaging in masturbation and petting, but least likely to report either comfort with their sexuality or sexual satisfaction. MSI Group women indicated that, while growing up, they were less attached to their mother and father figures, whom they rated as uncommunicative. They also were more likely to have engaged in risk-related sexual behaviors. SIO Group women were more likely to have used contraceptives at first sexual intercourse and to report fewer lifetime sex partners than MSI Group women. Since a substantial number of college women refrain from engaging in masturbation, yet choose to have unprotected sexual intercourse and multiple sex partners, and others engage in masturbation but report experiencing guilt feelings regarding self-stimulation, it is of crucial importance that the negative connotations of masturbation and its attendant impact on sexual satisfaction be addressed by sexuality educators, clinicians, and researchers.

Adolescent↗
PubMed1994

The role of computerized tomography in shoulder arthrography.

Double contrast computerized tomographic (CT) shoulder arthrograms of 55 shoulders were reviewed. This investigation was compared with conventional arthrograms and the findings were correlated with subsequent clinical and surgical follow-up. CT arthrograms were found to be useful in demonstrating bony, ligamentous and cartilaginous structures and have helped the surgeon in deciding the approach and type of surgical procedure. Indications for CT arthrography are recurrent dislocation, multidirectional instability, severe rheumatoid arthritis and other arthritides, complex shoulder deformities and suspected loose bodies. We found that this examination was not as helpful for rotator cuff injuries, impingement syndrome, adhesive capsulitis and in cases of vague or mild shoulder pain.

Adolescent↗
PubMed1993

Masturbatory guilt and sexual responsiveness among post-college-age women: sexual satisfaction revisited.

Although masturbation has come to be viewed as an appropriate sexual outlet for women, it is the one form of sexual behavior that has been most harshly treated throughout the centuries by society, religion, and the field of medicine. Thus, despite the increased incidence of masturbation among adult women during the 1970s and 1980s, substantial evidence suggests that guilt feelings associated with the practice may interfere with physiological and psychological sexual satisfaction in general. The purposes of this study were to determine the degree of masturbatory guilt, if any, and its effects on the sexual responsiveness and sexual satisfaction of adult women. An anonymous questionnaire concerning self-perception of the female sexual response was administered to female, registered nurses in 15 states, yielding a sample of 868 respondents. The 671 respondents who were the focus of this investigation had engaged in masturbation and revealed their guilt status regarding the practice. Those women who reported guilt feelings associated with masturbation were more likely to have negative feelings toward the practice and less likely to indicate positive physiological and psychological reactions after engaging in self-stimulation. Further, they were less likely to report sexual adjustment, physiological sexual satisfaction, and psychological sexual satisfaction. Since masturbation has emerged as a potential sexual outlet and as a means to engage in personal body exploration for women, these findings have substantial implications for therapists, physicians, sexuality professionals, and researchers.

Adult↗
PubMed1992

Immunological and metabolic responses of patients with history of antibody-induced beef insulin resistance to treatment with beef, pork, human, and sulfated beef insulin.

OBJECTIVE: We evaluated immunological and metabolic responses during therapy with beef (B), pork (P), human (H, rDNA), and sulfated beef (SB) insulins in patients with insulin-antibody-mediated insulin resistance. RESEARCH DESIGN AND METHODS: A randomized double-blind sequential crossover study was performed with each insulin administered for 56 days unless dose reached 200 U/day or allergy developed. Participants were 26 individuals with history of B-P insulin dosage greater than or equal to 200 U/day and insulin binding capacities greater than 0.216 nM (30 mU/ml serum). Twenty-one participants completed the study. Insulin dosage/day, fasting plasma glucose, percentage HbA1, insulin antibody binding capacity (IABC), bound insulin (BI), percentage binding of 125I-labeled B, P, and H insulins, and receptor inhibition factor (RIF) were assessed. RESULTS: Mean insulin dosage (U/day) was significantly greater on B (88.9) than on P (29.2), H (29.4), or SB (29.6). On B, dosage increased in 12 individuals and reached 200 U/day in 6 individuals. Mean fasting plasma glucose (12.1 mM) and HbA1 (11%) were significantly higher on B than on P, H, and SB. Mean IABC, bound insulin, RIF, and percentage of B, P, and H bound were significantly higher on B than on P, H, and SB. Prolonged treatment with SB before entry into the study (greater than 5 wk) resulted in a blunted anamnestic response to B insulin. CONCLUSIONS: Rechallenge with B results in anamnestic immunological response and deterioration of metabolic control. SB, H, and P insulins have equivalent effects in patients with insulin antibody-mediated immunologic resistance.

Animals↗
PubMed1991

The female sexual response revisited: understanding the multiorgasmic experience in women.

Although it has been almost 20 years since recorded evidence of multiple orgasms among women emerged, there have been few recent investigations of this phenomenon. The purpose of this study was to understand further the female multiorgasmic experience in relationship to the method of stimulatory activity, namely, masturbation, petting, and sexual intercourse. In addition, single-orgasmic and multiorgasmic women were compared by examination of various sexual and orgasmic behaviors, the role of sex partners, and perceptions of physiological and psychological sexual satisfaction. An anonymous 122-item questionnaire was utilized to obtain the responses of 805 college-educated female nurses, chosen for their perceived ability to verbalize data regarding the anatomical structures and physiological processes associated with sexual responsiveness. The findings indicated that 42.7% of the respondents had experienced multiple orgasms and that several significant differences existed between single-orgasmic and multiorgasmic women.

Adult↗
PubMed1991

Female sexual response and the timing of partner orgasm.

Although orgasm can be experienced in many ways with or without a partner, partner involvement continues to be a noted preference for many women. In order to examine the timing of partner orgasm in relationship to female sexual response, women who usually experience orgasm before, simultaneously, or after their male partner's first orgasm were examined in the context of their orgasmic behaviors, role of their partners in sexual interaction, and their level of sexual satisfaction. A survey research design, which utilized the responses of 709 adult women, indicated that those women who usually experienced orgasm after their male partners perceived less physiological and psychological sexual satisfaction. Furthermore, several other significant results were found regarding timing of partner orgasm. With the failure to reach orgasm through sexual intercourse being reported by women as a common sexual complaint, sex educators and therapists can use these findings to facilitate an increased awareness of timing factors influencing satisfying sexual relationships.

Adult↗
PubMed1990

Female ejaculation: perceived origins, the Grafenberg spot/area, and sexual responsiveness.

Despite earlier contrary claims, some researchers have recently reported a possible homologous female prostate gland that is potentially involved in a sudden spurt of fluid being released at the moment of orgasm. A number of medical authorities have speculated that this fluid is urine. To alleviate concerns about the possible release of urine during orgasmic response as well as to contribute to a further understanding of physiological and psychological sexual satisfaction, we examined a series of variables thought to be associated with female ejaculation [(expulsion of fluid during orgasm and its relationship, if any, to a sensitive anatomic area (Grafenberg spot)]. An anonymous questionnaire was distributed to 2350 professional women in the United States and Canada with a subsequent 55% return rate. Of these respondents, 40% reported having a fluid release (ejaculation) at the moment of orgasm. Further, 82% of the women who reported the sensitive area (Grafenberg spot) also reported ejaculation with their orgasms. A number of variables were associated with this perceived existence of female ejaculation.

Arousal↗
PubMed1990

Accident and emergency reporting in UK teaching departments.

A survey of 44 UK training departments shows that trainee radiologists commence accident and emergency (A & E) reporting after an average of 10.2 months in radiology and perform a considerable proportion of the A & E reporting workload. Most respondents consider that they supervise junior staff but only 11 departments directly check their work and only two departments offer supervision to staff with more than 2 years' experience. All A & E radiographs are reported in 79.9% of hospitals and the other hospitals operate selective reporting policies. The delay between the radiographic examination and the radiology report reaching the A & E department is less than 48 hours in about two-thirds of departments when the examination is performed Monday to Friday, but exceeds 48 hours in two-thirds of departments when it is performed at weekends. Misinterpretation of radiographs is one of the commonest errors in A & E. Improved supervision of less experienced trainees is required. Consultants should contribute and one should be responsible for this area. Radiological conferences are important and the secretarial services require major improvement.

Accidents↗
PubMed1989

Dysbaric disorders: aseptic bone necrosis in tunnel workers and divers.

Dysbaric osteonecrosis is a serious complication for those exposed to a hyperbaric environment, with prevalence of 17% amongst compressed air workers and 4.2% amongst divers. Bone lesions are characteristically multiple and bilateral, occurring frequently in the shafts of the femora or tibiae and the heads of the humeri or femora. A proportion of the lesions will lie next to the joint surface, the so called juxta-articular lesion, and these may progress to a structural failure and secondary osteoarthritis. These lesions can be severely disabling, especially in a young adult male. When related to the occupational history the prevalence of bone lesions, both in compressed air workers and divers, increases with age, experience and with greater pressures of air or at greater depths. Moreover, acute attacks of decompression sickness, the bends, are more liable to be associated with subsequent bone lesions. Current decompression schedules certainly reduce the bends rate but, no matter how strictly adhered to, will not prevent the development of dysbaric osteonecrosis. It is possible that bone necrosis could result solely from exposure to a high pressure of air, either from work in compressed air or diving. Those men with positive bone lesions should be advised to seek expert medical opinion and probably advised to discontinue work in compressed air or diving if a juxta-articular lesion is present. Detection of bone necrosis depends on good quality radiographs with reliable interpretation, preferably by double observation, especially in the early stages. Lesions, especially when early or doubtful, can be confirmed by CT or bone scintigraphy. MRI promises to detect osteonecrosis in the very early stages but is not yet readily available. To detect dysbaric osteonecrosis at an early stage it is important to monitor both compressed air workers and divers with regular radiological skeletal surveys or bone scintigraphy. In 1987, the Bone Necrosis Working Group of the Decompression Sickness Panel recommended that all divers should have a radiological survey on completion of their initial diving training and that bone scintigraphy should be used for subsequent surveillance for certain groups, including those diving deeper than 30 metres, where the time at depth exceeds 4 hours, when experimental decompression is used and in other situations.

Atmospheric Pressure↗
PubMed1989

The role of the Grafenberg Spot and female ejaculation in the female orgasmic response: an empirical analysis.

Despite earlier contrary claims, researchers have found evidence that a sensitive area (Grafenberg Spot) exists in the vaginal barrel. This area is a potential source of orgasm independent of clitoral stimulation. Other researchers have reported that some women experience a sudden spurt of fluid at the moment of orgasm. In the interest of contributing to further understanding of physiological and psychological sexual satisfaction, and alleviation of concerns about perceived urination during orgasm, the investigators explored a series of variables thought to be associated with perceptions of the Grafenberg Spot and its relationship, if any, to the female orgasmic response and female ejaculation. An anonymous questionnaire was distributed to 2,350 women in the United States and Canada, with a subsequent 55% return rate. A number of factors were found to be associated with perceived existence of a sensitive area in the vaginal barrel which, when properly stimulated, activates orgasm. Women who reported sensitive area orgasms were also more likely to report a spurt of fluid at moment of orgasm.

Body Fluids↗
PubMed1989

Single parents: interaction of parenting and sexual issues.

This study was designed to investigate how children affect the sexual lives of their single parents. More specifically, this study investigated how being a single mother or father affects parenting roles, partner relationships, sexual guilt, and sexual satisfaction. Data were collected from a sample of 155 parents who were members of a single-parenting organization. The findings revealed a significant difference between single mothers and single fathers regarding attitudes toward their relationship with their children. Although fathers more often reported being content in their parent-child relationships, they also were less frequently involved in the custodial care of the children. One of the major problems reported by single parents, especially mothers, was the relationship interference they perceived emanating from former spouses, children, and children of current partners. In addition, single parents also experienced guilt over their involvement with a relationship partner when it took time away from their children. Although the majority of single parents were satisfied with their sexual lives, there was a significant association between parent-child relationship and perceived sexual satisfaction for women. An increased awareness of the parenting roles and sexual lives of single parents can better enable family professionals to meet the needs of single parents as they act and react to changes in families and society.

Adult↗
PubMed1988

Radiographs in shoulder trauma.

It is difficult to establish the diagnosis of an injured shoulder if only one radiographic projection is used. We have compared two lateral projections, the Neer trans-scapular and the apical oblique in 80 patients; the radiographs were presented randomly to 10 casualty officers and nine radiologists. The apical oblique view was found to permit more accurate diagnosis of fractures and of dislocation by both groups.

Diagnostic Errors↗