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991.
The clinical course of 40 patients with histologically documented extracutaneous mycosis fungoides (ECMF) was reviewed. Thirty one patients had documentation of nodal disease only (Stage IVA). Nine patients had histologic evidence of visceral involvement (Stage IVB). A wide variety of topical, regional and/or systemic therapies were used in the management of these patients. The median survival for the entire group was 14.5 months. Eleven patients (28%) obtained a complete response (CR) and had a median survival of 21 months as compared with 8 months among 29 patients not obtaining a CR. One patient is without evidence of disease (NED) at 10 years. Multiple prognostic factors were examined with respect to survival. Prognostic factors found to be significant at the P = 0.05 level included ECMF at presentation of skin disease (versus at the time of relapse), the ability to achieve a CR, and management incorporating the use of topical therapy, especially electron beam treatment. Tabulation of all trials of chemotherapy either at diagnosis of ECMF or subsequently revealed that cyclophosphamide, vincristine and prednisone (CVP) and cyclophosphamide, vincristine, prednisone, and bleomycin (COP-Bleo) were the most effective chemotherapeutic combinations. In a multivariate analysis with survival as the endpoint, the best model consisted of only two covariates: ECMF at presentation of skin disease, and the use of topical therapy. Other covariates found not to be significant at the P = 0.05 level included age, gender, clinical extent of cutaneous and extracutaneous disease, Stage IVA versus Stage IVB disease, the presence of Sezary cells in the peripheral blood smear, and management incorporating the use of systemic therapy. 相似文献
992.
Ethnicity, bioethics, and prenatal diagnosis: the amniocentesis decisions of Mexican-origin women and their partners.
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Bioethical standards and counseling techniques that regulate prenatal diagnosis in the United States were developed at a time when the principal constituency for fetal testing was a self-selected group of White, well-informed, middle-class women. The routine use of alpha-fetoprotein (AFP) testing, which has become widespread since the mid-1980s, introduced new constituencies to prenatal diagnosis. These new constituencies include ethnic minority women, who, with the exception of women from certain Asian groups, refuse amniocentesis at significantly higher rates than others. This study examines the considerations taken into account by a group of Mexican-origin women who had screened positive for AFP and were deciding whether to undergo amniocentesis. We reviewed 379 charts and interviewed 147 women and 120 partners to test a number of factors that might explain why some women accept amniocentesis and some refuse. A woman's attitudes toward doctors, medicine, and prenatal care and her assessment of the risk and uncertainty associated with the procedure were found to be most significant. Case summaries demonstrate the indeterminacy of the decision-making process. We concluded that established bioethical principles and counseling techniques need to be more sensitive to the way ethnic minority clients make their amniocentesis choices. 相似文献
993.
Summary The subcutaneous implantation of devitalized, mineral-containing bone particles in rats elicits the recruitment and differentiation
of multinucleated cells and the rapid resorption of the bone. Cytochemical and ultrastructural characteristics were studied
12 days after implantation of bone. Tartrate-resistant acid phosphatase activity was demonstrated in these cells, especially
at the cell/bone interface. Mast cells were seen vicinal to, but not in contact with the osteoclasts and the bone particles.
Electron microscopic evaluation revealed that many multinucleated cells in lacunae on the surfaces of the bone particles displayed
features characteristic ofin osso osteoclasts, including clear zones of attachment to the bone substrate, and ruffled borders overlying bone with frayed collagen
fibers. Many cells contained multiple giant centrospheres; this finding suggests that fusion can occur between multinucleated
cells. This model may be useful to characterize the differentiation and regulation of bone-resorbing cells. 相似文献
994.
995.
A simple optical device (spectacles plus contact lens) enabling viewing of the real world with either partial or almost-complete retinal image stabilisation has been tested in patients with oscillopsia caused by nystagmus. The device gave a useful improvement in vision in two of 14 patients. Reasons for success and failure were clear and are discussed. Obvious contraindications include severe optic atrophy, titubation and dementia. Net benefit is also unlikely if there is a good null point or area to the nystagmus, or if acuity (corrected but unstabilized) is 6/9 or better. It is not suitable for the treatment of oscillopsia caused by failure of the vestibulo-ocular reflex. 相似文献
996.
It is thought that inhibition of dopamine reuptake into neurons may play a major role in the mechanisms by which cocaine produces its reinforcing effects. The striatum, while rich in dopamine terminals, is not implicated in drug reinforcement, whereas the mesolimbic dopamine pathway appears to play a primary role. It is therefore possible that the properties and drug sensitivities of the dopamine uptake systems in the nigrostriatal, mesolimbic, and mesocortical tracts differ. The effects of cocaine, GBR 12909, amfonelic acid, and methylphenidate on dopamine uptake in the striatum, nucleus accumbens, olfactory tubercle, and medial prefrontal cortex were examined. Over 80% of the dopamine uptake in each of the 4 regions was sodium-dependent and exhibited Km values of approximately 100 nM. Cocaine, GBR 12909, amfonelic acid, and methylphenidate each biphasically inhibited uptake in the striatum, nucleus accumbens and olfactory tubercle with GBR 12909 and amfonelic acid being approximately 50-fold more potent than cocaine or methylphenidate. In the medial prefrontal cortex, cocaine and GBR 12909 could inhibit only about 40% of the [3H]dopamine uptake. There are similarities in the properties and drug sensitivities of the dopamine uptake systems in brain areas which are implicated in drug reinforcement and those which are not. 相似文献
997.
Delayed visual loss due to trauma of the internal carotid artery 总被引:1,自引:0,他引:1
J M Weinstein D A Rufenacht C R Partington V B Graves C M Strother R E Appen D M Jacobson T A Cox M L Moster 《Archives of neurology》1991,48(5):490-497
The group of six patients in this study experienced delayed visual loss following head trauma. Visual loss occurred from 1 day to 13 years after the initial injury. All patients suffered indirect trauma to the internal carotid artery resulting in formation of either an aneurysm or pseudoaneurysm or a carotid-cavernous fistula. Review of the radiologic and clinical findings was performed in six patients. The diagnosis was established by computed tomography, magnetic resonance imaging, and angiography. All patients had follow-up clinical evaluation and imaging studies. Treatment by neurosurgical or interventional neuroradiologic procedures resulted in significant visual improvement in five patients. Different pathophysiologic mechanisms could be correlated with the delayed visual loss produced by the two types of lesions. The pathologic changes associated with the aneurysms/pseudoaneurysms included direct compression of optic nerves and/or chiasm and intracranial hematoma. A carotid-cavernous fistula caused delayed visual loss by either hematoma at the orbital apex or compression of the chiasm and/or optic nerves by saccular dilatation of the cavernous sinus. The delayed onset of decreased vision following head trauma should alert the physician to the possibility of a traumatic aneurysm/pseudoaneurysm or a carotid-cavernous fistula. Different neuro-ophthalmologic symptoms can usually be correlated with the pathologic changes demonstrated by neuroimaging procedures. 相似文献
998.
Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs. 相似文献
999.
The relationship of family income to the incidence, external causes, and outcomes of serious brain injury, San Diego County, California. 总被引:3,自引:1,他引:2
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Among residents of San Diego County, California the incidence and external causes of serious brain injury were related to the median family income of the census tract of residency. Low income tracts had high incidence rates--a finding not changed by adjustment for age and race/ethnicity. For those injured, the type of emergency transport, time from injury to treatment, and outcome of treatment were not related to the median income of the census tract of residency. 相似文献
1000.
Role of herniography in the diagnosis of occult hernias. 总被引:7,自引:0,他引:7
Twenty-two patients with groin or incisional pain and normal physical examinations underwent herniography. Eight patients were found to have 11 unsuspected hernias. Seven were direct, two indirect, and two incisional. Six of nine groin hernias were recurrent. Exploration confirmed the herniographic findings in all patients. Follow-up evaluation of patients undergoing herniorrhaphy revealed resolution of symptoms. Ten of the 14 patients with normal herniograms were asymptomatic 3 months after herniography. In these 22 patients, herniography resulted in a savings of $31,000. We conclude that herniography is cost-effective and useful in patients with abdominal wall pain of obscure etiology. 相似文献