Search PubMed⌕ Search

Biomedical subjects

H Martin

Publications and source records attributed to H Martin.

At least 271 records · Page 15Linked to original sources
PubMed1985

The attitudes of nurse tutor students to behavioural objectives: results and discussion.

This small-scale empirical study provides evidence of the attitudes of a group of nurse tutor students to behavioural objectives. The questionnaire items used ranged from questions about behaviourism and the use of behavioural objectives in teaching, to a question on whether the participants would use behavioural objectives in their teaching once they had finished their course. It emerged that while there was not an uncritical acceptance of behavioural objectives, they were seen as having a place in the process of teaching and learning nursing.

Adult↗
PubMed1985

Gradient separation of granulocytic progenitor cells (CFUc) from human blood mononuclear leukocytes.

Two different density-gradient techniques were compared for separation of human blood-derived granulocyte-macrophage progenitor cells (CFUc) from immunocompetent cells using albumin or Percoll as gradient media. Mean CFUc enrichment by means of discontinuous albumin gradient was twofold, whereas Percoll gradients yielded about 20- to 40-fold enrichment of CFUc in relation to lymphocytes. The pH of gradient media proved to have a major influence on separation quality. Based on these results and the development of a new density-separation technique in a 600-ml plastic bag, replacing customary Ficoll-Hypaque gradients, a method for large-scale purification of CFUc from leukapheresis-derived leukocytes has been constructed, working in a closed, sterile system. About 11 X 10(9) mononuclear cells containing 6 X 10(5) CFUc could be processed within 10 h. Lymphocytes were reduced to less than 1% of their initial number, and an average of about 50% of the original CFUc could be recovered.

Cell Separation↗
PubMed1985

[Malignancy grading of glial tumors. I. Astrocytomas].

A total of 91 fibrillar, protoplasmic and gemistocytic astrocytomas, 56 pilocytic astrocytomas and 70 glioblastomas, surgically obtained from 1973 to 1979, were evaluated. A four-grade malignancy system was applied to the astrocytomas. The grading criteria for the astrocytomas included quantitative cell density, cellular and nuclear polymorphism, mitotic activity, proliferative changes in the vascular elements and degree of necrosis. Using these criteria it was possible to distinguish four grades. Astrocytoma grades 1 and 2 correspond to the rubric "low-grade astrocytoma" in the English nomenclature, grades 3 and 4 to "high-grade astrocytoma". From the 91 fibrillar, protoplasmic and gemistocytic astrocytomas there were 12, 29, 31 and 19 tumors in grades 1 to 4 respectively. The corresponding distribution for the 56 pilocytic astrocytomas was 20, 29, 6, 1. Median survival for the fibrillar, protoplasmic and gemistocytic group for malignancy grades 1-4 were 43.8, 33.5, 8.4 and 5.6 months respectively. The corresponding figures for the pilocytic astrocytomas grades 1-3 were greater than 66, greater than 69, and 20.0 months.

Adult↗
PubMed1985

[Significance of immunohistochemistry in neuro-oncology. I. Demonstration of glial fibrillary acid protein (GFAP) in extracranial metastases from primary brain tumors].

8 cases were studied to determine whether immunohistochemical investigation with anti-GFAP could contribute to confirming a primary brain tumor origin for an extracranial metastasis. The materials studied consisted of 3 glioblastomas, 3 anaplastic astrocytomas, and 2 medulloblastomas, along with their extracranial metastases. GFAP could be immunohistochemically demonstrated in all 6 primary glial tumors as well as in the metastases of the 3 astrocytomas and of 2 glioblastomas. The medulloblastomas and their metastases were immunohistochemically GFAP-negative. GFAP is thus a marker for extracranial metastases of astrocytomas and glioblastomas. A negative result however does not exclude the possibility that a metastasis is of glial origin as shown by the GFAP-negative metastasis of the one glioblastoma.

Adult↗
PubMed1985

[Diencephalic pilocytic astrocytoma with clinical onset in infancy. Biological behavior and pathomorphological findings in 11 children].

Pilocytic astrocytomas of the diencephalon with onset of signs and symptoms during the first year of life are reported in 7 boys and 5 girls. Failure to thrive was the initial manifestation in 5 infants. In 2 of them a Russel syndrome emerged. The growth rate of the tumors was slow. One child survived without treatment for 2.5 years. The survival time of the treated children ranged from 7 months to 6 years and 4 months. All children died. No obvious indications of neurofibromatosis were found. All tumors infiltrated and destroyed the hypothalamus. In addition, the tumor infiltrated the optic chiasm in 3 cases and extended into the optic nerves in 2 of them. Most of the astrocytomas were large. Their maximal diameter exceeded 10 cm in 2 children. All were pilocytic astrocytomas grade 1. The grade of malignancy was the same in recurrences as in the initial operative material. Rosenthal fibres were uncommon. It is concluded that diencephalic pilocytic astrocytomas biologically and morphologically resemble most of the pilocytic astrocytomas occurring in early life in other parts of the brain. There is, therefore, no justification for regarding them as a separate tumor entity.

Astrocytoma↗
PubMed1985

[Peculiarly slow development of several acoustic neuromas. Management].

Thirteen patients presented with neurinomas of particularly slow evolution, including 5 cases with a history of over 20 years chronicity. These cases appear to be more common after 60 years of age and correspond often to stage I and II tumors. The decision to operate to resect the tumors is a difficult one to make, particularly in the bilateral forms.

Adult↗
PubMed1984

Automated image analysis of gliomas an objective and reproducible method for tumor grading.

A system of automated microscopic picture analysis was used in an examination of 272 gliomas (70 glioblastomas, 91 astrocytomas, 56 pilocytic astrocytomas or spongioblastomas , and 55 oligodendrogliomas). The specimens were prepared as Feulgen sections, 4 microns in thickness. Thirteen morphometric-densitometric parameters of tumor cell nuclei were tested together with two mitotic parameters. Objective and reproducible data on numerical nuclear density ( KRNZ , AREA), nuclear size ( KOFL , KFRL , P250 ), nuclear shape ( FOFK , FOFR , P150), optical density ( EXTU , EXTS , EXSR , EXTM , EXMR ), and mitotic activity ( MITZ , VHMK ) of the gliomas were obtained from the morphometric-densitometric parameters. All gliomas but glioblastomas were subdivided by four tumor grades. The morphometric-densitometric and mitotic data recorded were statistically checked, depending on tumor grade (Student's t-test, Wilcoxon's test, alpha = 0.05). Numerical nuclear density, deformation of nuclei, and mitotic activity were found to grow with significance along with increasing tumor grade up to glioblastoma. The relative standard deviation (SD) of nuclear size ( KFRL ), relative SD of shape factors ( FOFR ), and relative SD of extinction sums ( EXSR ) are high-accuracy parameters for the pathologist to describe variability of sizes, polymorphism, and polychromasia of nuclei. These parameters show a significant increase of values in parallel with rising tumor grade, with maximum values being recordable from cases of glioblastomas. In cases of astrocytomas, optical values of nuclei decrease along with rising tumor grade. The data thus obtained were used as reference values for objective, reproducible automatic glioma grading. The classifier method, described in an earlier publication, proved to be more effective than the regression method.

Astrocytoma↗
PubMed1984

Chronic lumbar intrathecal catheterization in the rat with reduced-length spinal compression.

The present paper describes an original technique, chronic lumbar catheterization of the subarachnoidal space in the rat. Introducing the catheter into the rachis directly at lumbar level reduces the length of the intrathecal catheter and, consequently, the extent of spinal cord compression. The validity of the technique is proved by the dose related effect obtained after morphine injections and the staining of the only spinal part of the central nervous system after blue-dye injections.

Animals↗
PubMed1984

The in vitro and in vivo effect of estradiol upon the 17 alpha-hydroxylase and C17,20-lyase activity in the ovaries of immature hypophysectomized rats.

The effect of a single injection of estradiol benzoate upon the activity of 17 alpha-hydroxylase and C17,20-lyase in the ovaries of hypophysectomized immature rats was investigated. Tritiated H2O from 17 alpha-[3H]progesterone and 14CH3COOH from 21-[14C]progesterone were the products measured to evaluate the hydroxylase and lyase activities respectively. Estradiol (E2) had no direct effect upon the activity of the enzymes in vitro even when present at twice the concentration of the substrate. However, when given in vivo, E2 reduced the activity of both enzymes. The ratio of the activities remained constant supporting the contention that both enzyme activities reside in one cytochrome P-450. Cycloheximide attenuated, but did not prevent, the reduction obtained with estrogen. Enzyme activities were reduced by E2 to a slightly lesser degree when the ovaries had been exposed in vivo to exogenous gonadotropin for 72 h. The results indicate that 17 alpha-hydroxylase and C17,20-lyase activities decrease when large doses of E2 are administered in vivo, that this effect is not directly on the enzymes, and that at least a part of this effect involves macromolecular synthesis.

Aldehyde-Lyases↗
PubMed1984

[Primary intracranial tumors as cause of death in the fetus and infant].

Clinical and pathomorphological findings in 2 stillborn and 15 lifeborn children with primary intracranial tumors are reported. All infants died within the first year of life and the tumors were confirmed histologically. In 6 children the tumors (3 intracranial teratomas, 1 glioblastoma, 1 hemangioblastoma, 1 choroid plexus papilloma) were present at birth. All 6 were born with pathologically enlarged heads. Another child exhibited symptoms of brain tumor at the age of three weeks. The tumor was probably present at birth as well. In the remaining infants the signs and symptoms of tumor development became evident some months after birth. These tumors might have occurred postnatally. In a girl aged 9 months, a nephroblastoma of the right kidney and a malignant cerebral tumor, probably a glioma, were present. An incidental coexistence of both tumors is considered, however, a common etiology cannot be excluded. 8 of the 17 intracranial tumors were supratentorially situated. This supports the view that the proportion of supratentorial tumors is higher in early life than in older children.

Adolescent↗
PubMed1984

[Injections of fibrin glue in severe epistaxis and Rendu-Osler disease].

Our experience of the control of epistaxis by "in situ" injections of tissucol is essentially based on the use of this procedure for the treatment of epistaxis associated with Rendu-Osler's disease. We reported our first trials of this technique at the meeting organised by Immuno France Laboratories in Bordeaux in November 1983. Since this time, our initial experience has been greatly enriched, with very good results. We have treated two unusual cases of very severe epistaxis which did not respond to any of the treatments administered. We feel that these special cases warrant being reported in order to demonstrate the value of this technique.

Adult↗
PubMed1984

[Importance of meningioma. Clinico-epidemiologic and histologic studies].

The clinical data and histological findings of 195 patients operated on because of meningiomas have been evaluated for the comparative epidemiological-morphological study of the biological validity of meningiomas under special consideration of the incidence of recidivation and malignant transformation. These were 127 women (65%) and 68 men (35%). The incidence peak of the tumour diseases for both sexes was found to lie between the 40th and the 59th year of age showing a frequency of 61 per cent. The assessment of the biological validity of meningiomas was based on the localisation, growth rate and recidivity of the tumours including histological criteria in the sense of the grading system after Zülch. The incidence of malignant meningiomas may amount to up to 10 per cent of the meningioma cases; the share in our own patients was 5.1 per cent. The incidence of recidivation of meningiomas was found to be 11.5 per cent after total tumour removal and 32 per cent after subtotal operation. The rate of the recurrence of meningiomas of the base was 52 per cent, thus being considerably higher than that of meningiomas of other localisations (3-28%). Malignant meningiomas show a particularly high recidivity. Among our own patients, there were ten cases of malignant meningiomas with 15 relapses (150%) while 185 benign meningiomas only showed a total of 30 relapses (16%). Invasive growth was found in the meningioma form classified histologically as malignant with 2.5 higher frequency than that of the benign forms of meningiomas. In recurrent tumours a malignant transformation of primary benign meningiomas was found. Malignant meningiomas with a formation of extraneural metastases are rare. Until now, only 72 cases have been reported in the literature.

Adolescent↗
PubMed1984

[Karyometric studies of meningiomas].

Of a total of 195 bioptically diagnosed meningiomas of the Pathological Institute of the Humboldt University Berlin of the period of 1963 to 1976, 21 meningiomas (5 endotheliomatous, fibromatous and angiomatous meningiomas, 6 malignant meningiomas) were selected and 10 parameters evaluated for a comparative morphometric analysis. The evaluated parameters describe quantitatively the numerical density of the nucleus, the size of the nucleus, the size of the nucleoli and the nucleus/plasma relation. Malignant meningiomas are distinguished from benign meningiomas by a significant enlargement of their nuclei, of the nucleoli and the nucleus/plasma relation. On the other hand, the numerical density of the nuclei can only be used conditionally for the discrimination of malignant and benign meningiomas; the numerical density of the nuclei of the malignant meningiomas is lower than that of the endotheliomatous meningiomas and larger than that of the fibromatous and angiomatous meningiomas. The article demonstrates the possibility to obtain a differentiation of groups of typical cases of malignant and benign meningiomas on the basis of morphometrical data. Conventional morphometry is a time consuming process and thus not suitable for routine work. In connection with automatic image evaluation procedures (automated microscopic image analysis, cytophotometry) ways are opened up for a wider application of morphometry and densitometry and a classification of individual tumour preparations.

Brain↗
PubMed1984

Endosonic endodontics: the ultrasonic synergistic system.

A biotechnological approach using ultrasound has led to the development of a method of root canal therapy in which effective debridement, shaping, irrigation and disinfection of the root canal are easily and quickly completed. This is achieved by a handpiece and a file both energized by ultrasound. A flow-through component enables an irrigation solution to pass along the file into the canal system. The ultrasonically energized file activates the irrigant facilitating solvent, cleansing and disinfecting actions within the root canal system. The energized file is able to debride the canal wall with great facility in an extremely rapid and simple fashion. Progress in metallurgical bonding has enabled a diamond coated file to be developed which gives efficient and rapid preparation of the root canal. Use of this combination of ultrasound, flow-through irrigation and diamond-coated files enables the dentist to perform endodontic treatment expeditiously while adhering to biologic principles.

Anti-Infective Agents↗
PubMed1984

[Primary neuroblastoma of the mandible. Apropos of a case].

Concerning an observation of mandibular neuroblastoma, the problem of a probable primary localization of this neurocristopathy is raised on the face level. Actually, classically speaking, it can only be a question of metastasis revealing a tumor initially located in the abdomen, the thorax, or more rarely in the pelvis or the neck. However, the evolution of the lesion under treatment leading to complete cure within three years denies the secondary nature of the process. Related to the three other cases in the world that have so far been published, our observation enables to assert the reality of the primary development of a neuroblastoma on the mandibular level. The coherent reasoning is founded on the role of neural crests in facial embryogenesis whose vitiation offers a logical explanation to this exceptional phenomenon.

Child↗