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PubMed1975

Health manpower: numbers, distribution, quality.

Although the "health care crisis" was thought solvable by simply increasing the number of physicians, this has turned out not to be the case. The major problems in physician manpower are geographic maldistribution with a sparsity of physicians in the rural areas and the inner city and an overproduction of specialists. Certain changes in undergraduate and postgraduate medical education have contributed to this maldistribution. There is good evidence that there is an overproduction of surgeons and of medical subspecialists such as cardiologists. Much of the excess subspecialization can be laid at the foot of graduate training programs. The role of the specialty boards in affecting career choices and with them health manpower is analyzed. Some solutions to solve the geographic and specialty maldistribution problems are suggested. It is clear that more primary care physicians including general internists, family physicians, and pediatricians are needed.

Career Choice↗
PubMed1999

Effects of local density on pollination and reproduction in Delphinium nuttallianum and Aconitum columbianum (Ranunculaceae).

Plant populations vary in density both naturally and as a consequence of anthropogenic impacts. Density in turn can influence pollination by animals. For example, plants in dense populations might enjoy more frequent visitation if pollinators forage most efficiently in such populations. We explored effects of plant density on pollination and seed set in the larkspur Delphinium nuttallianum and monkshood Aconitum columbianum. At our site in the Colorado Rocky Mountains, flowers of D. nuttallianum are pollinated primarily by queen bumble bees, solitary bees, and hummingbirds, whereas those of A. columbianum are pollinated primarily by queen and worker bumble bees. We found that the quantity of pollination service to both species (pollinator visitation rate and pollen deposition) was at best weakly related to density. In contrast, seed set declined by approximately one-third in sparse populations relative to nearby dense populations. This decline may stem from the receipt of low-quality pollen, for example, inbred pollen. Alternatively, sparsity may indicate poor environmental conditions that lower seed set for reasons unrelated to pollination. Our results demonstrate the value of simultaneously exploring pollinator behavior, pollen receipt, and seed set in attempting to understand how the population context influences plant reproductive success.

Journal Article↗
PubMed2000

Divergent differentiation in neuroendocrine tumors of the adrenal gland.

Composite tumors of the adrenal medulla usually consist of pheochromocytoma admixed with ganglioneuroma or ganglioneuroblastoma. These neoplasms reflect phenotypic plasticity shown by primitive sympathetic cells and mature chromaffin cells in vitro. They may give rise to metastatic neuroblastoma in adults and may cause signs and symptoms attributable to both catecholamine and neuropeptide production. Schwann cells and sustentacular cells are typically numerous in these tumors but it is not known whether they are neoplastic. Immunohistochemical staining for catecholamine biosynthetic enzymes, secretory vesicle proteins and S-100 protein tends to recapitulate staining of the normal adrenal medulla or sympathetic ganglia. Sparsity of chromogranin A in the cell bodies of immature and mature neurons is a diagnostically useful characteristic.

Adrenal Gland Neoplasms↗
PubMed2000

Bisphosphonates in the prevention and treatment of glucocorticoid-induced osteoporosis.

OBJECTIVE: To summarize the literature concerning the use of bisphosphonates in the prevention and treatment of corticosteroid-induced osteoporosis and make recommendations concerning the proper use of these agents. SEARCH STRATEGIES: We conducted a literature search to identify studies in the English language concerning the use of bisphosphonates in the prevention or treatment of corticosteroid-induced osteoporosis using the MEDLINE, CURRENT CONTENTS, and HEALTHSTAR electronic databases, bibliographies of selected citations, and recent meeting abstracts. SELECTION CRITERIA: We included randomized controlled trials evaluating the use of oral bisphosphonates in adults by central dual X-ray absorptiometry. DATA COLLECTION AND ANALYSIS: We assessed the methodologic quality of the trials using the Jadad criteria. Data were collected concerning bone mineral density (BMD) changes in multiple areas, fracture rates, safety, and tolerability. MAIN RESULTS: Bisphosphonates generally increased BMD at the lumbar spine. Data were less clear concerning changes in the femoral area. Little information exists about the ability of bisphosphonates to reduce fracture risk in patients with corticosteroid-induced osteoporosis. Postmenopausal women seemed to receive the most benefit. CONCLUSIONS: Bisphosphonates significantly increased BMD in patients at risk for corticosteroid-induced bone loss. However, there is a sparsity of data concerning the ability of these agents to affect the clinically important outcome of fracture rate reduction, especially among premenopausal women in whom fractures are rare within the first year or 2 of exposure to corticosteroids. Long-term studies powered to detect fracture risk reduction are needed as well as comparative trials with bisphosphonates and other agents.

Adult↗
PubMed1983

[The population and character of traditional communities in insular Southeast Asia].

"This article discusses the character of population distribution and its relation to the structure of societies and states in Insular Southeast Asia in the early and mid nineteenth century. Except in Java and Bali, populations were characterized by sparsity, diversity, smallness, and mutual independence. Despite the effects of crisis mortality, the long-term population growth in the traditional period seems not to have been much different from [that] in India and China, which suggests the smallness of the original or early populations." The author notes that new communities were formed by the separation of settlements in frontier regions and that these patterns continued into the middle of the nineteenth century. The traditional order seems to have broken down in the late nineteenth century as a result of the combined pressures of colonialism and population increase. (summary in ENG)

Asia↗
PubMed1992

Evaluating drug prescribing in a large, ambulatory population: application of an embedded expert system.

DUR is a process of problem detection and intervention designed to improve the quality and economy of drug prescribing. Retrospective DUR attempts to detect and address patterns of prescribing that might be indicative of inappropriate therapy. When the process is extended to a largely ambulatory population such as Medicaid beneficiaries, a number of complications are introduced due to the large numbers of patients and sparsity of data. In order to examine the impact of implementing a Medicaid DUR program, we developed a system that would apply screening criteria to prescription claims. It has been used to screen prescribing of groups of two antihypertensive drugs in the 1990 Maryland Medicaid population for 177,409 Medicaid eligible individuals. Potentially significant problems were detected with respect to dosing, duplication of therapeutic agents and drug interactions. The system represents, we believe, a significant improvement in the ability to detect and report prescribing decisions by increasing the specificity of the detection system. By the application of this system to a set of real-world data, we have demonstrated that it is feasible to implement such a system and derive results that are potentially useful in reducing the incidence of inappropriate physician decision-making.

Ambulatory Care Information Systems↗
PubMed1992

[Coronary artery bypass grafting for a patient with hypothyroidism--a case report].

A 59-year-old female who had been treated for hypothyroidism was admitted with angina pectoris and underwent aorto-coronary bypass grafting. On closing of the sternum, there was unexpected bleeding from the suture line between the vein graft and the ascending aorta. Histological examination of the aortic wall revealed sparsity and disruption of elastic fibers and deposition of mucopolysaccharide without any findings of atheromatous change. It is concluded that hypothyroidism can cause histological change of the aortic wall and that surgical procedures involving the aortic wall in patient with hypothyroidism should be avoided if possible.

Aorta↗
PubMed1992

Psychological state and running economy.

The primary purpose of the present review was to critique studies that examined the influence of psychological state (i.e., affect, perception, and cognition) on running economy (RE). However, only six studies included measures of oxygen consumption at a given workload (i.e., economy) and used running as the mode of exercise. Two of the six studies indicated that increased tension was highly correlated (r = 0.81) with increased oxygen cost and that reductions in tension, using stress management techniques, improved RE. Because of the sparsity of studies in this area, a secondary purpose of this review was to examine the influence of psychological state on the physiological and behavioral response to varying modes of exercise. Affect, induced through hypnosis and imagery, was effective in changing the response to exercise (i.e., heart rate, performance). Altered perception through the use of hypnosis or through personality characteristics did not alter the physiological response to exercise, perhaps because of the passive role of the exerciser in these situations. Lastly, cognition (i.e., mental strategy, coping, and biofeedback) elicited changes in the physiological and behavioral responses to exercise. Despite these physiological alterations, there were not changes in oxygen consumption in the majority of the studies. It is possible that changes in selected physiological responses (i.e., respiratory frequency) may be altered (e.g., biofeedback) without changes in oxygen consumption because of accommodation in other areas of the body (i.e., a-VO2 difference). Changes in economy possibly occur when these accommodation effects are overridden by the physiological adaptations resulting from longer training periods. In conclusion, psychological state can influence the physiological and behavioral response to exercise. Furthermore, this review supports the use of a multidisciplinary approach to examine the interactional effects of physiology, biomechanics, psychology, and neurophysiology to adequately determine mechanisms underlying changes in RE.

Affect↗
PubMed2005

Sustaining the rural primary healthcare workforce: survey of healthcare professionals in the Scottish Highlands.

INTRODUCTION: Many westernised countries face ongoing difficulties in the recruitment and retention of health professionals in remote and rural communities. Predictors of rural working have been identified by the international literature, and include: the individual having been born or educated in a rural location; exposure to rural healthcare during training; access to continuing professional education; good relationships with peers; spousal contentedness; adoption of a rural 'lifestyle'; successful integration into local communities; and educational opportunities for children. However, those themes remain unverified in the UK. The present study aimed to ascertain whether the internationally identified determinants of recruitment and retention of the rural health workforce apply in the Highlands of Scotland, which includes the most sparsely populated area of the UK mainland, as well as an urban area. METHODS: In 2003, a questionnaire was sent to all 2070 primary healthcare professionals working in the Highlands (which makes up one-third of Scotland's land area (9800 square miles) and has just 4% of the country's population (209,000)). Approximately one-quarter of the Highland's population live in Inverness. The area is ideal for investigating the rural workforce due to its population sparsity and the inclusion of small towns and Inverness, allowing urban/rural comparisons. The questionnaire asked about places of birth and education; intentions to stay/leave current location; professional isolation; access to amenities; and perceptions of belonging to the local community. RESULTS: The response rate was 53%. Compared with respondents working in urban areas, those working in rural areas were more likely to have been born in rural areas. Professionals living in rural areas were more likely to have been born outside Scotland and to have completed their secondary education and professional training outside Scotland, compared with those living in urban areas. Approximately one-third (34%) had lived in their current location for more than 10 years, and that proportion was higher for the urban group compared with rural dwellers. Similarly, the urban dwellers were more likely to have been in their current job for more than 10 years. Respondents' perceptions of being isolated, of their caring roles extending beyond their work; and of an inability to get away from work for holidays and study leave, were more common among rural dwellers. Eighty-one percent of respondents said that they felt part of their community and that proportion was higher for those working in rural areas, than for urban residents. Respondents indicated their perceived ease of access to five amenities and services: children's education (preschool, primary and secondary); access to a job for spouse; and health care. With the one exception of access to primary education, access was perceived to be most difficult by the professionals working in rural areas. CONCLUSIONS: Our survey confirms, in the UK, the association between rural background and rural working, and highlights the contribution of healthcare professionals from other parts of the UK to the Scottish rural workforce. It also suggests that professional isolation and perceived lack of access to amenities are important issues for those working in rural areas.

Adult↗
PubMed1992

Primary mesenchymal chondrosarcoma of the lung. A case report with immunohistochemical and ultrastructural studies.

A case of primary pulmonary mesenchymal chondrosarcoma is reported. The tumor occurred first in the lower lobe of the right lung of a Japanese female aged 45. Three years after the first operation it metastasized to the upper lobe of the left lung. The tumors were highly cellular and composed of undifferentiated mesenchymal cells and interspersed islands of well-differentiated cartilaginous tissue. Immunohistochemistry failed to detect S-100 and vimentin in the undifferentiated cells. In contrast, Leu-7 and blood coagulation factor XIIIa were positive in these cells. Electron microscopically, undifferentiated mesenchymal cells had narrow cytoplasm with sparsity of organelles, but no intermediate-sized filaments were detected. In the transitional areas between undifferentiated cells and cartilaginous components, thin intracytoplasmic filaments were sometimes observed in the tumor cells. The differentiation toward cartilaginous cells of undifferentiated mesenchymal cells was suggested by immunohistochemistry and electron microscopy. This is the first case of mesenchymal chondrosarcoma occurring in the lung with long-term follow-up.

Chondrosarcoma↗
PubMed1991

Overcoming methodological barriers to HIV/AIDS nursing research.

While more than 1,600 articles have been published in the nursing literature about HIV infection, only 54 (3%) have been research articles. The sparsity of nursing research related to HIV has partially resulted from methodological problems inherent in the implementation of research protocols with persons infected with HIV. The authors' focus is on methodological and ethical problems related to sampling patterns, informed consent, and protection of human subjects that have hindered the study of HIV infection. The underlying reasons for these problems as well as solutions and approaches to minimize or prevent the problems are presented.

Clinical Protocols↗
PubMed1976

Multilaminar endoplasmic reticulum and abnormal mitosis in Hodgkin tumor cells.

A multilaminar alteration of endoplasmic reticulum (ER) has been observed in tumor cells of eight patients with Hodgkin's disease and a patient with histiocytic lymphoma. These multilaminar structures are more numerous in dividing cells and thus appear to arise primarily during mitosis. The stacked membranes in the multilaminar structures possibly result from abnormal sticking of organelle membranes, as evidenced in this study of adherence of ER to other elements of ER, nuclear envelope, mitochondria, or lipid droplets. Multilaminar ER was identified in all mitotic tumor cells, a rare mitotic plasma cell, and numerous interphase Hodgkin cells. The paucity of multilaminar ER in normal mitotic cells and its virtual absence for normal interphase cells suggest that this structure represents a pathological alteration in tumor cells from patients with Hodgkin's disease and histiocytic lymphoma. The multilaminar defect of ER is associated with other atypical features of ER in Hodgkin tumor cells, including the excessive length and curving of ER profiles, the collapse of the ER cisternae, and the overall sparsity of this organelle. Other abnormalities observed in mitotic Hodgkin tumor cells include the presence of disorganized microtubules, large cytoplasmic vacuoles, and abnormally clumped chromosomal material and the persistence throughout mitosis of bodies suggestive of nucleoli and of the nuclear bodies of interphase cells.

Cell Nucleus↗
PubMed1991

Hereditary hair changes revealed by analysis of single hair fibres by scanning electron microscopy.

In many disorders with a genetic background the sparsity of scalp hairs may deter the clinician from trying to extract information from single hair fibres. Presenting a number of diverse conditions, we propose to show that simple measures can be taken in the doctor's office which makes single fibre analysis a useful tool for assessment of factors involved in genetic disorders including the integument and its appendages. The paper is focussed on the utilization of the scanning electron microscope with the goal of demonstrating that pertinent information can be gained where information from transmission electron microscopy and other techniques are not immediately available.

Adolescent↗
PubMed1991

Assessment of regionalized perinatal programs.

This paper addresses issues encountered in studies of the effectiveness of regionalized perinatal care. Regionalization of perinatal care has been actively promoted based upon the intuition that regionalization should reduce perinatal mortality and morbidity. When assessing the effectiveness of a perinatal service, one is interested in whether the service is being utilized appropriately and, if utilized appropriately, whether it is impacting upon outcome. Studies of utilization of regionalized perinatal care include studies of: utilization of the tertiary centre, non-utilization of the tertiary centre and antenatal transfer patterns. Studies of program impact are few. There is one quasi-experimental study which examines mortality and morbidity impact of a program and a few studies examining indirect hypotheses of the impact of regionalization on mortality. Despite the sparsity of the literature, there is evidence in the papers reviewed that regionalization of care may have impact on both mortality and morbidity. Further studies of the latter are needed. Further studies might also include measures of satisfaction of care providers, satisfaction of patients and maternal attachment, among others. In addition, since preliminary evidence implies that regionalized perinatal care is effective, future studies might include considerations of cost-effectiveness.

Female↗
PubMed1989

Scleroderma.

This article reviews the literature on scleroderma and pregnancy, highlighting its sparsity, confused state, and retrospective nature. It emphasizes the need for more informed prospective work. This is required for clinical management and to help understand the complex interaction between scleroderma and pregnancy. This relationship is poorly defined and research is needed to investigate hormonal status, femaleness, and the disease.

Counseling↗
PubMedDate not supplied

"Repair cells" in equine uterine cytologic and histologic specimens.

Cells resembling those known as "repair cells" in gynecologic cytology specimens from women were identified in uterine cytology specimens from infertile mares treated with antibiotics using indwelling uterine catheters. This prompted a study of the effect on the equine uterus of indwelling catheterization without antibiotic infusion, using light microscopic examination of cytologic and biopsy specimens and electron microscopic examination of biopsy specimens. Cytologic and biopsy specimens had features within normal limits at the start of the study. Following five days of indwelling catheterization, neutrophils were present in both cytologic and biopsy specimens. In cytologic specimens, numerous groups of "repair cells" were present; similar cells in biopsy specimens indicated this was a focal reaction. The large nuclei and prominent nucleoli of the "repair cells" suggested cellular proliferation or regeneration. However, this was contradicted by the ultrastructural sparsity of ribosomes, endoplasmic reticulum, Golgi apparatus and mitochondria. Inflammation and "repair cells" were not present in cytologic or biopsy specimens collected 40 days after the start of the study. Although these cells may be a component of a repair process, our results support the hypothesis that "repair cells" in human and equine gynecologic cytology specimens are injured, rather than regenerating, cells. The term dysphaneroplastic (Greek: "abnormal cytosol development") is proposed to describe these cells since the cytoplasm does not reflect the features of cellular activity suggested by the nuclear appearance.

Animals↗
PubMed1988

[Effect of cholecystokinin-octapeptide on the motor function of the digestive tract of the plaice].

The influence of cholecystokinin-octapeptide on the bioelectrical features of gastro-intestinal motility in sea-water fish (plaice) was investigated in chronic experiments. I. v. or intracerebral application of the peptide led to inhibition of the stomach cardia motor activity, to intensification and sparsity of the tonic and peristaltic contractions of the stomach pyloric part, and to an increase in the intestine fore-part activity. Vagotomy prevented the effect of intracerebral application of cholecystokinin. Atropine prevented this effect of cholecystokinin irrespective of the mode of its application. Phentolamine or propranolol did not alter the effect.

Animals↗
PubMedDate not supplied

Megakaryocytes and ganglion cells mimicking cancer in fine needle aspiration of the prostate.

In six cases, fine needle aspiration (FNA) directed at prostatic lesions produced specimens containing megakaryocytes or ganglion cells, which are sources of potential diagnostic error in the interpretation of aspirates of the prostate gland. In three cases, apparent accidental penetration of the tip of the transrectal FNA biopsy needle into the ischium instead of the prostate resulted in the aspiration of megakaryocytes and other bone marrow elements; the megakaryocytes mimicked anaplastic cancer. Three additional FNAs of the prostate produced specimens containing a small number of ganglion cells mimicking well-differentiated adenocarcinoma; the accompanying strands of wavy neural tissue served as a clue to the ganglionic origin of these potentially misleading cells. The paucity of "atypical" cells and the sparsity or absence of prostatic epithelium in the aspirates were additional clues to the cytologist that the findings represented an anatomic misplacement of the FNA biopsy needle tip, rather than a prostatic cancer.

Adenocarcinoma↗