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H Hoffman

Publications and source records attributed to H Hoffman.

At least 37 records · Page 2Linked to original sources
PubMed1997

A flexible and extensible object-oriented 3D architecture: application in the development of virtual anatomy lessons.

"Anatomic VisualizeR" represents the first application to be developed using a 3D architectural framework created at the University of California, San Diego, School of Medicine. This application combines 3D anatomic models (based on the Visible Human dataset) with supporting 2D media (e.g., diagnostic imagery, surgical videos, etc.) to establish a comprehensive learning environment for anatomy. "Guided lessons" are being created to address complex curricular and learning objectives. Faculty expertise is represented in these preconfigured lessons, in part through the specification of appropriate content and the incorporation of activities to enhance visualization. These lessons are an intellectual framework which ensures that clinically-relevant issues and ancillary learning opportunities are available. The curricular exercises are non-sequential and can be interrupted at any time; users are encouraged to freely explore the environment. At the core of Anatomic VisualizeR's object-oriented architecture is the ability to identify, access, view, and manipulate heterogeneous content. The capacity to query a database gateway to retrieve specified resources has been built into the application. Encapsulation of individual elements to form 3D display objects ("blocks") enables Anatomic VisualizeR to efficiently manage 3D models, 2D images, text, sound, and video. The "block" paradigm also allows Anatomic VisualizeR to associate contextually appropriate display characteristics and behaviors with the various content elements. For example, the anatomic model block provides the capability to "link" and "unlink" the anatomic models and to alter their transparencies. The anatomic models can be displayed concurrently with other blocks to facilitate structural comparisons. Anatomic VisualizeR marks a major milestone in our developmental efforts. While lessons and database content are still not complete, we are confident that it will become the first tangible realization of our vision.

Anatomy↗
PubMed1997

Birth weight of relatives by maternal tendency to repeat small-for-gestational-age (SGA) births in successive pregnancies.

BACKGROUND AND METHOD: Small-for-gestational-age (SGA) infants represent a heterogeneous group of normal and growth-retarded children. To assess the familial aggregation of reduced fetal growth, birth weights in both maternal and paternal relatives of 1246 index children in the Scandinavian SGA Study were compared across groups defined by the SGA outcome of the index child as well as that of earlier siblings. RESULTS: Mean maternal birth weight +/- SEM was 3127 +/- 54 g for mothers who had experienced two SGA births as opposed to 3424 +/- 22 for mothers with no SGA births. Mean paternal birth weight was 3497 +/- 88 g and 3665 +/- 24 in the same two groups. The odds ratio (with 95% confidence interval) for having a mother with birth weight below the 10th percentile was 1.74 (0.85-3.58) for the group where two SGA births had occurred compared to no SGA births and it was 2.49 (1.22-5.07) for having a father with birth weight below the 10th percentile. There was no correlation between maternal and paternal birth weights. CONCLUSIONS: The association also to paternal birth weight suggests the presence of genetic or common environmental factors in explaining the tendency to have SGA children. Although taking parental birth weights into consideration will aid in diagnosing growth-retardation in a SGA child, SGA remains a heterogeneous group where familial and non-familial cases will be difficult to separate.

Birth Weight↗
PubMed1997

[Microinvasive cervical cancer].

While the rate of invasive carcinoma of the cervix is relatively constant among women under 40 years of age, the rate of microinvasive carcinoma (MIC) appears to increase steadily in this young age group. The definition of MIC is not universally established and if the probability of dissemination of the disease is low, it is not unconceivable and calls for an adequate surgical treatment that should respect the anatomic and functional integrity of these young women. The diagnosis of MIC relies primarily on conisation that is indicated in severe dysplasia and cervical neoplasia with no evidence of invasion on colposcopic directed biopsies. Conisation is the standard approach that requires a rigorous surgical technique and a thorough histological evaluation of the surgical sample by a skilled pathologist. This pathologic examination should be particularly attentive to the depth of stromal invasion, the width and volume of the lesion and the magnitude of LVI. While the dissemination within the parametrium cannot be well assessed, it appears that the likelihood of pelvic lymph node involvement approximates the depth of stromal invasion of the MIC with a threshold limit of 3 mm. LVI also carries the risk of poor prognosis, particularly in the early stages of the disease, and has been taken into consideration by the Society of Gynecologic Oncologists (SGO). The standard treatment of MIC is also conisation under the condition that the surgical limits are not diseased. If the depth of stromal invasion exceeds 3 mm or if LVI is reported by the pathologist, the lesion should then be treated like an invasive carcinoma of the cervix (i.e.: colpohysterectomy and pelvic lymphadenectomy). In some instances however (e.g.: early invasion with LVI), a laparoscopy directed pelvic lymphadenectomy could be suggested as a first line investigation associated with conisation. Since early invasive carcinoma of the cervix can now be defined and carries a reduced spreading potential we can propose an adequate treatment allowing functional integrity in these patients in a particularly young age group.

Biopsy↗
PubMed1995

Brain tumors in children: long-term survival after radiation treatment.

PURPOSE: To determine the cause of death in children who survive more than 5 years after radiation treatment of a brain tumor. METHODS AND MATERIAL: Nine hundred and twelve consecutive children with a primary brain tumor irradiated at the Princess Margaret Hospital or Toronto-Bayview Regional Cancer Center from 1958 to 1991, were evaluated for long-term outcome. RESULTS: Overall 10- and 20-year survival rates were 44% and 37%. Subsequent survival of 377 5-year survivors was, at an additional 10 and 20 years, 78% and 67%. Most (83%) deaths that occurred more than 5 years from diagnosis were a result of relapse of the original tumor. The 10-year survival rate subsequent to relapse was 9% when the first relapse occurred less than one year from diagnosis, 17% for 1-2 years, and 31% when the time to relapse was 3 years or greater. The cumulative actuarial incidence of, and death from, second malignant tumors at 30 years from diagnosis was 18% and 13%, respectively. CONCLUSIONS: Death later than 5 years from diagnosis of a brain tumor in children is common and is usually due to progressive disease in slowly evolving low grade tumors. Death from a second malignant tumor becomes more frequent than death from the original tumor after 15 years from diagnosis.

Adolescent↗
PubMed1995

The role of magnetic resonance angiography in head and neck surgery.

Magnetic resonance angiography (MRA) is a recently developed, noninvasive vascular imaging technique. The authors of this investigation assessed the diagnostic value of MRA, along with its influence on therapeutic decisions, in 11 patients with a variety of head and neck disorders. In 5 patients, MRA diagnosed or ruled out an intrinsic vascular lesion. MRA was used to evaluate 5 of 8 patients with cancer for evidence of direct tumor involvement of vascular structures. Other uses of MRA included preoperative determination of tumor vascularity and delineation of anatomic relationships between normal vessels and head and neck pathology. Overall, MRA results guided management in 10 patients, and in some cases it determined the extent of surgical intervention. Because MRA is safer and more practical than traditional angiography, the authors recommend more frequent use of this imaging technique in the practice of head and neck surgery.

Adult↗
PubMed1995

Virtual reality-multimedia synthesis: next-generation learning environments for medical education.

The Learning Resources Center of the University of California, San Diego School of Medicine has begun to investigate the potential of virtual reality (VR) as a tool for medical education. We are currently integrating VR with communications, animation, and visualization technologies to form a hybrid learning and training environment. Our program development reflects a curriculum-based strategy with emphasis on instructional objectives and educational outcomes. Demonstrated need, feasibility of a technology-based solution, and appropriateness of resource allocation are primary considerations. As the VR world is built, comparative analyses are being made of control strategies, display options, and interface design.

Computer Simulation↗
PubMed1994

Amnesia and vegetative abnormalities after irradiation treatment: a case study.

This paper describes a case of a patient (GX) with a brain tumour in the third ventricle who developed a syndrome of amnestic disorder and vegetative abnormalities (hyperphagia, oligodipsia) after irradiation treatment that followed brain surgery. The patient shows an extremely poor long-term memory on both visually and verbally presented material, and of autobiographical events occurring after the onset of the illness, but some preserved memory functions on short-term memory tasks, semantic memory tasks, and implicit memory tasks. Given the onset of symptoms only after irradiation (a memory deficit in particular), and the non-invasive nature of the surgery, the probable etiology is post-irradiation syndrome.

Adult↗
PubMed1994

Oral antibiotic usage in hospitalized patients.

With the introduction of the fluoroquinolones, oral antibiotic usage is becoming an increasingly important issue. The medical record of 119 patients receiving oral antibiotics at a university hospital were reviewed to examine demographics and patterns of usage. The population was predominantly female and below 50 years of age. Urinary tract infections were most common followed by infections of the respiratory tract and skin and skin structure. The majority of usage was empiric in nature. The most commonly prescribed antibiotics were trimethoprim/sulfamethoxazole, cephalexin, and ampicillin/amoxicillin. Monotherapy with an oral agent was observed in 82% of the cases. Intravenous antibiotics were administered prior to oral therapy in 61% of the patients studied. The authors observed a trend from combination intravenous therapy to single-agent oral therapy. Of the patients discharged on an oral antibiotic, 84% received a prescription for the agent originally prescribed for them in the hospital. Tracking of oral antibiotic inpatient use is effective at assessing major trends in usage.

Administration, Oral↗
PubMed1994

[Why compare hepatosplenic bilharziasis in six African countries with the help of ultrasonography? Presentation of a WHO project including Madagascar].

During a morbidity survey in two endemic foci of hepatosplenic schistosomiasis in the malagasy Hauts Plateaux (Tetikanana, 80 km East of Ambositra and Lohanosy, in the vicinity of Antananarivo), the objectives of a comparative pathology WHO project are presented. The survey in Madagascar was concurrently organized by the Ministry of Health (Bilharziasis central laboratory, DLMT), the Parasitology Unit of the local Pasteur Institute and the Medical Parasitology Institute of Bonn University, in Germany. This was the fourth part of this investigation of the morbidity variation due to Schistosoma mansoni infection in six african countries, a project sponsored by the WHO within its TDR programme. This comparison was based on the standardized description of morbidity as visualized by echography, following the "Cairo-1990" and the "Hannover-Managil-1989" classifications, and on coprology. One of the main objectives of this study was to demonstrate a morbidity variation at the scale of the African region (due to different S. mansoni strains or to a variable genetic background within the studied human populations), while participating to an international standardization effort for field echography. The project was conducted since July 1991 by a constant medical staff from Bonn and Hannover german universities. Eight foci in four african countries (Senegal, Mali, Uganda and Madagascar) are still analyzed and we are presenting here the first results. The data of an independent ultrasonographic investigation, organized by the Blair Institute and the Danish Bilharziasis Laboratory in Zimbabwe, was kindly proposed for this comparison. This project will end with the study of two supplementary foci in Tanzania and Burundi.

Africa↗
PubMed1994

Prenatal care access and pregnancy outcomes in Missouri.

Women's access to prenatal care and perception of barriers to obtaining care were acquired from data derived from the 1990 NICHD/Missouri Maternal and Infant Health Survey. Maternal surveys were available for 479 fetal deaths, 902 VLBW, 802 MLBW, and 919 normal birth weight infants. Very low birth weight mothers were less likely to receive prenatal care, perceived more barriers to obtaining prenatal care, and were more unhappy about their pregnancy than were the mothers of normal weight infants.

Female↗
PubMed1994

Basic clinical skills in occupational medicine.

By incorporating the principles of occupational medicine into their practices, physicians can better help those patients with job-related disorders and can improve the management of patients whose non-work-related conditions have implications for their employment. This article focuses on occupational history, physical examination skills, investigation of work sites, risk assessment, screening and surveillance, fitness-to-work evaluations and disability assessment, administration, prevention, health education and general communication, and ethical issues.

Health Education↗
PubMed1991

Drug response of head and neck tumors in native-state histoculture.

We describe a chemosensitivity testing of head and neck tumors, in which a native-state histoculture, ie, a three-dimensional culture system that maintains important in vivo properties, including tissue architecture, was used. Fifteen specimens of head and neck tumors were evaluated for sensitivity to the following drugs: cisplatin (DDP) at concentrations of 1.5, 15, and 37.5 micrograms/mL; fluorouracil at concentrations of 4.0, 40, and 100 micrograms/mL; and combinations of cisplatin and fluorouracil in corresponding doses. Growth and measurement of drug responses were successfully completed in 10 specimens (five others were contaminated, four of them prior to instituting rigorous antibiotic washes). The results indicated cisplatin sensitivity in five of 10 patients; fluorouracil sensitivity in four of 10 patients; and fluorouracil-cisplatin sensitivity in seven of eight patients. Our preliminary results indicate that the native-state histoculture technique is feasible to test chemosensitivity of head and neck tumors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Automatic processes in word perception: an analysis from illusory conjunctions.

When asked to report the color of a target letter in a briefly presented word or pseudoword, Ss were more likely to report the color of letters from the same syllablelike unit than the color of other letters. Because Ss were not required to make a lexical decision or naming response, the multiletter units that are revealed by this task arise automatically. It was found that the syllablelike units are not phonological but correspond to orthographic patterns and morphemes. These units affect performance regardless of changes in letter-case, suggesting that the units are based on abstract letter identities. Unit formation was also not affected by visual field of presentation. Several experiments demonstrated that the morphological and orthographic units arise from different processes: The morphological units depend on lexical access, and the orthographic units do not. Finally, the effects of orthography are stronger for good readers than for poor readers.

Adolescent↗
PubMed1991

Eye fixations and memory for emotional events.

Subjects watched either an emotional, neutral, or unusual sequence of slides containing 1 critical slide in the middle. Experiments 1 and 2 allowed only a single eye fixation on the critical slide by presenting it for 180 ms (Experiment 1) or 150 ms (Experiment 2). Despite this constraint, memory for a central detail was better for the emotional condition. In Experiment 3, subjects were allowed 2.70 s to view the critical slide while their eye movements were monitored. When subjects who had devoted the same number of fixations were compared, memory for the central detail of the emotional slide was again better. The results suggest that enhanced memory for detail information of an emotional event does not occur solely because more attention is devoted to the emotional information.

Adult↗
PubMed1990

Risk of neural tube defects in relation to maternal fertility and fertility drug use.

In a case-control study to investigate whether women who use drugs to induce ovulation are at increased risk of conception of a child with a neural tube defect, 571 women who had a fetus or child with a neural tube defect, 546 women who had a fetus or child with other abnormalities, and 573 women who had an apparently normal fetus or child were questioned about infertility, fertility drug use, and related obstetric problems. The rate of maternal fertility drug use around the time of conception was not significantly higher for neural tube defects than for other abnormalities (odds ratio 1.28; 95% confidence interval 0.39, 4.51) or no abnormalities (odds ratio 0.80; 95% Cl 0.27, 2.27). Fertility drug use at any time was not significantly more frequent for neural tube defects than for other abnormalities (odds ratio 1.37; 95% Cl 0.70, 2.74) or no abnormalities (odds ratio 1.05; 95% Cl 0.56, 1.98).

Abnormalities, Drug-Induced↗