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At least 19 recordsLinked to original sources
PubMed1991

Medical student interest in internal medicine. Initial report of the Society of General Internal Medicine Interest Group Survey on Factors Influencing Career Choice in Internal Medicine.

OBJECTIVE: To determine the factors that attract students toward and push students away from a career in internal medicine. DESIGN: National survey of senior U.S. medical students using a stratified random cluster sampling of medical schools. PARTICIPANTS: The survey included 1650 U.S. senior students from 16 medical schools, of whom 1244 (76%) responded. MEASUREMENTS AND MAIN RESULTS: A survey instrument was developed and pilot tested at 17 medical schools. Twenty-four percent of the respondents to the final survey chose a career in general internal medicine (9%) or subspecialty internal medicine (15%). A career in internal medicine had been "seriously considered" by 608 respondents (50%) who finally chose a career other than internal medicine (the "switchers"). Compared with other specialties, internal medicine was perceived as being more stressful to residents, more demanding of time and workload as a career and a residency, and as an easier residency to enter. Internal medicine was also seen as providing less satisfaction for residents, having lower income potential, and allowing less leisure time. For the 608 switchers, the most important influences leading to their decision to switch were the type of patient seen in internal medicine (for example, chronically ill, alcohol and drug abusing patients) as well as dissatisfaction and stress among internal medicine residents. Factor analysis showed that three factors, "intellectual challenge of internal medicine," "primary care interests," and "the medicine clerkship" attracted students toward internal medicine, whereas three others, "taking care of chronically ill patients," "level of satisfaction among internists and medical residents," and "workload and stress" pushed students away from internal medicine. Factors pushing students away from internal medicine were significantly more negative with regard to a career in general as opposed to subspecialty internal medicine (P less than 0.001). CONCLUSION: Medical students have serious reservations about internal medicine as a career choice. Perceptions about the medical residency, the patients they expect to see, and the dissatisfaction among residents and internists are foremost in their thinking. Changes to improve the attractiveness of internal medicine should address these adverse perceptions while building on the positive influences identified by the respondents.

Career Choice↗
PubMed1989

The future of general internal medicine. Council on Long Range Planning and Development in Cooperation with the American College of Physicians, the American Society of Internal Medicine, and the Society of General Internal Medicine.

The American Medical Association Council on Long Range Planning and Development has been publishing a series of reports that assess trends in the environment of medicine and their impact on physicians and health care provision. The Council believes that each specialty in medicine has unique characteristics and will respond differently to changes in the health care arena. This report, developed in cooperation with the American College of Physicians, the American Society of Internal Medicine, and the Society of General Internal Medicine, provides an overview and environmental analysis of the specialty of general internal medicine. The Council first reviews socioeconomic data pertinent to general internal medicine. This is followed by a review of key issues pertinent to internists that relate to such topics as graduate medical education, reimbursement, scope of practice, manpower, and competition. In the conclusions, the Council suggests activities for the medical profession to pursue in response to the identified environmental trends.

Adult↗
PubMed1991

Mutagenesis of the human transferrin receptor: two cytoplasmic phenylalanines are required for efficient internalization and a second-site mutation is capable of reverting an internalization-defective phenotype.

Site-specific mutagenesis has been used to define the sequences required for efficient internalization of the human transferrin receptor. It has previously been shown that the sole cytoplasmic tyrosine, at position 20, is required for efficient internalization. When two other cytoplasmic aromatic residues, the phenylalanines at positions 13 and 23, are substituted with alanines internalization is also reduced. The phenylalanine 23 mutation decreases the internalization rate constant approximately threefold, and mutation of phenylalanine 13 decreases it by approximately twofold. The mutation at position 23 has as serious an effect on internalization as substitution with a nonaromatic amino acid for the single tyrosine. These results demonstrate the importance of several aromatic amino acids in maintaining efficient internalization of the transferrin receptor. Substitution of a tyrosine at a second site, for a serine at position 34, within the cytoplasmic domain of a transferrin receptor with a nonaromatic amino acid at position 20, results in a complete reversion of the internalization-defective phenotype. This reversion is completely dependent upon a tyrosine, as phenylalanine substituted at position 34 does not revert the internalization-defective phenotype. This result demonstrates that a tyrosine placed outside of its native context can still function in the internalization of the transferrin receptor, suggesting a flexibility in surrounding sequences required for efficient internalization.

Amino Acid Sequence↗
PubMed1978

Effects of internal free calcium upon the sodium and calcium channels in the tunicate egg analysed by the internal perfusion technique.

1. The unfertilized egg of the tunicate, Halocynthia roretzi, was intracellularly perfused with various solutions. 2. The perfusion apparatus consisted of lower and upper compartments which were connected by a small glass funnel. A denuded egg cell without chorion was dropped into the funnel and brought into close contact with the glass wall of the funnel. The membrane of the egg faced to the lower compartment was ruptured by a slight difference of hydrostatic pressure and the inside of the egg was perfused with the internal solution flowing through the lower compartment. The current across the upper membrane was analysed by voltage-clamp technique. 3. The egg cell in contact with 400 mM-Na external solution and perfused intracellularly with 400 mM-Na for 30 min showed a relatively low Na reversal potential, +6 mV, in comparison with +60 mV in the intact egg in standard artificial sea water. The exchange efficiency was monitored by observing the shift of Na reversal potential during perfusion with high Na internal perfusate. 4. The internal perfusate containing F- ions stabilized the egg membrane and kept the excitability for 1--2 hr during the intracellular perfusion. With the internal F- perfusate the intracellular cationic content was changed to 400 mM-Na, K, Rb or Cs (external solution of 400 mM-Na) and permeability ratios of the egg Na channel were estimated as PNa:PK:PRb:PCs=1.0:0.14:0.05:0.04. The internal F- perfusate abolished Ca current which was consistently observed in the intact egg, while the internal Cl- perfusate kept both Na and Ca current as in the intact egg. However with the internal Cl- perfusate the egg cell could not be kept in good condition more than 20-30 min. 6. The effects of intracellular free Ca ions upon the egg Na and Ca channels were analysed by using Ca ion-buffered internal Cl- and high Na perfusate. The results showed that internal Ca ions above 10(-6) reduced the Ca current and enhanced the Na current at the same time. In the range between 10(-5) and 10(-4) M the Ca current became half of the control obtained with zero free Ca perfusate while the Na conductance at the zero current level doubled. The internal Ca ions above one mM seemed to abolish the Ca current and to reduce the Na current as well. The reciprocal effect of intracellular Ca ions upon the egg Na and Ca channels was demonstrated in the concentration range from 10(-6) to 10(-3) M.

Animals↗
PubMed1990

National Study of Internal Medicine Manpower: XVII. Changes in the characteristics of internal medicine residents and their training programs, 1988-1989.

The National Study of Internal Medicine Manpower (NaSimm) has been surveying program directors of internal medicine about their programs and residents for 13 years. The 1988-1989 survey results, when compared with the results for 1987-1988, show an increase in both the number of residency positions offered in internal medicine and the number of residents in internal medicine programs. Although the proportion of graduates from U.S. medical schools who choose internal medicine is not changing (34%), the proportion of U.S. medical school graduates who continue training in internal medicine after their first year is decreasing. The composition of the residents in internal medicine by medical school graduated is also changing. Almost 25% of the first-year residents (R1s) in internal medicine are now graduates of foreign medical schools (FMGs) compared with 14% in 1976. The proportion of first-year female residents in internal medicine has increased to 30%, whereas the proportion of both first-year blacks and Hispanics has remained constant at 5% each. In nearly 25% (109 of 440) of the residency programs, more than 50% of the R1s are FMGs. Hispanics, Asians, and blacks were found to be over-represented in the programs training larger proportions of FMGs. This over-representation is attributable, in part, to the fact that Hispanics and Asians may be FMGs. Training issues of concern to program directors continue to be the provision of ambulatory and primary care experiences and the scheduling of nights on call. The survey results show that many residency program directors have reported a reduction in the number of nights on call and an increase in the amount of time residents spend in ambulatory training.

Ethnicity↗
PubMed1992

General internal medicine in internal medicine: at the core or on the periphery?

In the past decade, faculty in sections of general internal medicine have assumed responsibility for training residents, for staffing clinical practices, and for developing new domains of health services and effectiveness research. These activities form the core of internal medicine: They are integral to the role of internal medicine as an academic and patient care discipline, and they complement the activities of the internal medicine subspecialties. The effect of general internal medicine on internal medicine, therefore, has been to shift the focus away from the subspecialty services--which compartmentalize a patient's medical problems--and back to the concept of the patient as a "whole" person. The role and territory of the general internist are changing as a result of this shift in focus, and general internal medicine is emerging as the new core discipline in internal medicine. These changes have allowed for an expanded capacity of internal medicine to provide new services, modified curricula, and innovative research.

Holistic Health↗
PubMed1987

Meridian-like networks of internal organs, corresponding to traditional Chinese 12 main meridians and their acupuncture points as detected by the "Bi-Digital O-Ring Test imaging method": search for the corresponding internal organ of Western medicine for each meridian--Part I.

The "Bi-Digital O-Ring Test" imaging method has been successfully used not only to outline the internal organs but also malignant tumors as long as identical reference control tissue is available, regardless of whether it comes from the same individual or others, without exposing the patient to undesirable radiation from X-Rays, strong magnetic field or ultra-sound. While imaging the outline of the internal organs the author found that, from the surface of each organ, lines or networks of lines extend to other parts of the body. Such a line closely resembles well-known lines of meridians of major internal organs in Oriental medicine. This meridian-like network of each internal organ can be imaged using a microscopic slide, dessicated tissue or raw tissue of the same internal organ as reference control substance in "Bi-Digital O-Ring Test" imaging method. In previous papers, among meridians of 12 main internal organs in Traditional Chinese Medicine, the author was able to find which meridian corresponds to which internal organ of Western Medicine as in 10 meridians by "Bi-Digital O-Ring Test" imaging with corresponding internal organs as reference control substances, with the exception of "Pericardium Meridian", and "Triple Burner Meridian". In this study we were able to confirm that the "Pericardium Meridian" can be imaged mainly using adrenal gland as a reference control substance and "Triple Burner Meridian" can be imaged by the ovary or adrenal gland in the female and also can be imaged by the testes or adrenal gland in the male. Thus, the author was able to confirm, for the first time, the corresponding internal organ of Western Medicine for each one of the 12 main meridians. During this study, when actively imaging the meridian-like network, the author found bulging areas of the meridian-like network at specific locations, and found that these bulging areas correspond to specific acupuncture points. The area or average diameter of these acupuncture points often increased in the abnormal area and returned relatively small normal diameter by acupuncture given on certain acupuncture points of the same meridian. Thus, one can find the exact location of the meridian-like network and specific acupuncture points along the network. Therefore, it is now possible to re-evaluate true effects of giving acupuncture on these specific points as well as some of the other classical concepts of acupuncture.

Acupuncture Therapy↗
PubMed1992

General internal medicine and general internists: recognizing a national need. Federated Council for Internal Medicine.

The Federated Council for Internal Medicine (FCIM) comprises the American Board of Internal Medicine, American College of Physicians, American Society of Internal Medicine, Association of Professors of Medicine, Association of Program Directors in Internal Medicine, and the Society of General Internal Medicine. The Council was established in 1975 to speak with a collective voice for the specialty of internal medicine. In 1992, the Council developed the following statement in conjunction with its endorsement of a target of 50% of internal medicine residency graduates entering the practice of general internal medicine.

Career Choice↗
PubMed1989

[A case report of hypoplasia of the root portion and the intermediate portion of the left internal carotid artery associated with an unusual primitive collateral circulation between the left internal carotid artery and the left external carotid artery].

The internal carotid artery is one of the most stable arteries and its absence is very rare. We reported a case of hypoplasia of the root portion and the intermediate portion of the left internal carotid artery associated with an usual primitive collateral circulation between the left internal carotid artery and the left external carotid artery. A 57-year-old male developed right hemiparesis of sudden onset 3 days prior to admission. On admission, right hemiparesis and right minimal facial palsy was observed. The left direct carotid angiogram revealed that the root portion and the intermediate portion of the left internal carotid artery were hypoplastic. There was an unusual primitive collateral circulation between the left internal carotid artery and the left external carotid artery. From an embryological point of view, normally, the internal carotid artery is derived from the third aortic arch and the dorsal aorta when the embryo is attained the 3-mm stage. The root portion of the internal carotid artery is formed from the third aortic arch. The dorsal aorta between the third and the first aortic arch form the intermediate portion. The distal part of the internal carotid artery originates from the dorsal end of the first aortic arch. The common carotid artery begins to form in the 12-mm to 14-mm embryo, following involution of portion of the ventral aortic root between the third and the fourth aortic arch. The external carotid artery arises from the aortic sac and migrate up to the third aortic arch.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta, Thoracic↗
PubMed1992

Receptor-mediated internalization of bradykinin. DDT1 MF-2 smooth muscle cells process internalized bradykinin via multiple degradative pathways.

This study was undertaken to evaluate the role of internalization in the action of the peptide autacoid bradykinin (BK). At 4 degrees C [3H]BK binds to an apparently single class of B2 kinin receptors on DDT1 MF-2 smooth muscle cells (C. M. Munoz, S. Cotecchia, and L. M. F. Leeb-Lundberg, manuscript submitted). At this temperature the [3H]BK binding was confined exclusively to the cell surface. On the other hand, at 37 degrees C the B2 receptor-specific cell surface [3H]BK binding was rapidly followed by a receptor-specific internalization of [3H]BK (t1/2 approximately 9 min). The internalization reached a steady-state level after 30-40 min that was 80-100% of the level of specifically bound [3H]BK on the cell surface at 4 degrees C, and this level was maintained for greater than or equal to 2 h. Internalized [3H]BK was routed via at least two intracellular degradative pathways which were distinguished primarily based on subcellular localization but also on a small but significant difference in the rate of [3H]BK degradation. One pathway was localized in a plasma membrane-enriched fraction and had a relatively high degradative capacity. Another pathway was localized in a microsomal fraction and had a relatively low degradative capacity. The internalized [3H]BK activity was rapidly released into the media (t1/2 approximately 24 min). Following a single round of internalization, the released activity consisted almost exclusively of small [3H]BK fragments (less than [3H]BK(1-5)). In contrast, at steady-state [3H]BK represented 30-40% of the released activity. While chloroquine (100 microM) did not alter the rate of [3H]BK internalization or release or the intracellular distribution of [3H]BK, this agent significantly decreased the rate of [3H]BK degradation in both pathways. In all, these results show that B2 kinin receptor-mediated internalization of BK is a process integral to the interaction of BK with DDT1 MF-2 smooth muscle cells and may be a mechanism for terminating BK actions by rapidly removing extracellular free and receptor-bound BK and accessing various intracellular BK degradative pathways.

Amino Acid Sequence↗