Search PubMed⌕ Search

Biomedical subjects

M Swanson

Publications and source records attributed to M Swanson.

87 records · Page 5Linked to original sources
PubMedDate not supplied

Medical implications of ultrasonically detected polycystic ovaries.

Polycystic ovaries are usually manifest on an ultrasound study as symmetrically enlarged ovaries containing numerous tiny cysts. The cysts are difficult to detect with conventional contact B-scanners but are readily detected with high-resolution, real-time sector scanners. The cysts range in diameter form 2 to 6 mm and may be arranged in the periphery of an ovary or throughout the parenchyma. In patients with ultrasonically demonstrated polycystic ovaries (aged 15 to 35 years), there is a spectrum of clinical findings. Half the patients have most of the classic signs and symptoms (hirsutism, menstrual irregularity, and obesity) associated with Stein-Leventhal syndrome. Twenty-five percent have variants of the syndrome. In another 25%, no clinical abnormality is evident at the time of an ultrasound examination.

Adolescent↗
PubMedDate not supplied

Filtered versus unfiltered technetium sulfur colloid in lymphatic mapping: a significant variable in a pig model.

BACKGROUND: Lymphatic mapping with sentinel node biopsy is becoming a standard diagnostic test for melanoma and is being extensively investigated for use with other soft tissue tumors. Both filtered and unfiltered technetium sulfur colloid (Tc 99) have been used for preoperative lymphoscintigraphy, as well as intraoperative lymphatic mapping, and it is not clear if one is preferable over the other. The purpose of this study was to compare these two preparations to determine whether the form of Tc 99 used affects the results of lymphatic mapping. METHODS: Mock skin sites were placed on each extremity of 12 domestic pigs totaling 48 skin sites. Twenty-four of the lesions were injected with unfiltered Tc 99; the remaining 24 were injected with Tc 99 passed over a 0.2-microm filter. Both preparations of Tc 99 were mixed with 1 mL of isosulfan blue before injection. Sentinel node dissection was performed using a gamma probe, with counts recorded over a 10-second period and timed to begin 5 minutes after injection. RESULTS: Sentinel nodes were identified in all 48 lymph node basins draining the mock sites and characterized as hot (10x background), blue, or both. Significantly more sentinel nodes were found in the filtered (105 total, X = 4.4/basin), than in the unfiltered group (total 53, X = 2.2/basin, P <.0001). The filtered group had both a higher number of nodes that were hot (35 vs. 6) and more nodes that were hot and blue (69 vs. 43). In addition, hot secondary level lymph nodes (iliac and deep cervical) were found in 11 of 24 of the basins (46%) in the filtered group compared to 1 of 24 (4%) in the unfiltered group (P <.003). There was no significant difference in injection site or residual basin counts between the two groups, but in vivo counts over the sentinel node sites were significantly lower in the unfiltered group (X = 2670+/-1829 vs. X = 6027+/-4333; P = .003). CONCLUSION: Use of filtered Tc 99 results in more sentinel nodes (both hot/blue and hot non-blue) and a higher proportion of secondary lymph nodes. These findings indicate that the Tc 99 preparation used is a significant variable in the results of lymphatic mapping. It is critical that future clinical studies document which preparation of Tc 99 was used. Only large clinical trials will be able to determine whether the additional nodes found with filtered Tc 99 increase the sensitivity of the technique or merely increase the number of nodes that must be removed unnecessarily.

Animals↗
PubMedDate not supplied

Drinking water, fluid intake, and bladder cancer in western New York.

Fluid intake and consumption of specific beverages were investigated in a study of 351 white male cases for whom transitional cell carcinoma of the bladder had been confirmed histologically during the time period from 1979 to 1985. A total of 855 white male controls was selected from Erie, Niagara, and Monroe counties of western New York state. Total fluid consumption was composed of alcoholic beverages, bottled beverages, soda, milk, coffee, tea, all juices, and glasses of tap water. Tap water included coffee, tea, juices, and glasses of water taken directly from the tap. Total fluid consumption was found to be a strong risk factor for bladder cancer when a number of potential confounding risk factors were controlled for. Risks were higher among those who were less than 65 y of age (odds ratio [OR] = 6.3, 95% C.I. = 2.8-14.0). The OR was 3.4 (95% C.I. = 1.8-6.2) for the highest quartile of fluid consumption among those 65 y of age and older. The tap water component was associated with increased risk in both age categories, and there was a clear dose-response relationship. Risks associated with tap water consumption were higher among those who never smoked cigarettes. Both biological and nonbiological explanations for these results are evaluated. The findings suggest implications for public health, but the limitations of the present investigation preclude definitive conclusions and stress the urgency for replication.

Adult↗
PubMedDate not supplied

The reproductive and developmental toxicity of High Flash Aromatic Naphtha.

Catalytic reforming is a refining process that converts naphthenes to aromatics by dehydrogenation to make higher octane gasoline blending components. A portion of this wide boiling range hydrocarbon stream can be separated by distillation and used for other purposes. One such application is a mixture of predominantly 9-carbon aromatic molecules (C9 aromatics, primarily isomers of ethyltoluene and trimethylbenzene), which is removed and used as a solvent--High Flash Aromatic Naphtha. A program was initiated to assess the toxicological properties of High Flash Aromatic Naphtha since there may be human exposure through inhalation or external body contact. The current study was conducted to assess the potential for developmental toxicity in the mouse and for reproductive toxicity in the rat. In the developmental toxicity study in CD-1 mice, exposure of dams by inhalation to near lethal levels (1500 ppm) resulted in fetal mortality, reduced weight, delayed ossification, and an increased incidence of cleft palate. At 500 ppm, a level at which maternal weight gain was slightly reduced, fetal weight gain was also reduced, but there was no other evidence of developmental effects. The lowest exposure level (100 ppm) did not cause any maternal or developmental toxicity. There was no consistent evidence of reproductive toxicity in rats, even at exposure levels which resulted in significantly reduced parental weight gain. In addition, when parental exposure was stopped on GD (gestation day) 20, birth weights as well as postnatal survival were generally similar to control values, even in the 1500 ppm exposure group. Postnatal weight gain was also similar to controls early in weaning, but, if maternal exposure was reinitiated, weight gain was reduced in the high exposure group. However, when exposure was continued until delivery, pups in the high exposure group exhibited reduced litter size, birth weight and poor survival. Thus it was likely that the reduction in fetal weight, seen in the developmental toxicity study in mice, was transient and had no postnatal consequences if maternal exposure was terminated at any time prior to delivery.

Administration, Inhalation↗
PubMedDate not supplied

Alteration of renal blood flow during sequential embolization of the canine kidney.

Experimental embolization of the renal artery with cross-linked dextran (CLD) microspheres was performed in 6 dogs. The blood flow was monitored by electromagnetic flow meter (EM) in 3 dogs and by video dilution technique (VDT), adapted to an angiographic digital subtraction system, in a second group of 3 dogs. Retrograde flow in the embolized renal artery was detected by 99Tcm microspheres. Sequential emboli produce a predictable and equal flow response with both measuring techniques. Thus, the less invasive VDT can be used in the clinical setting to optimize and control embolization procedures. This type of flow monitoring has great potential in alerting the angiographer when approaching the risk level for retrograde flow.

Animals↗
PubMedDate not supplied

The use of patient complaints to improve service delivery.

In this paper changes to the procedures involved in making complaints are outlined. The alterations in the process follow on from the Department of Health's response to the Wilson report. The new guidelines for dealing with complaints are designed to be simpler and more explicit in order to encourage members of the public to make their concerns known. The ways in which complaints can be used positively to improve on services are outlined.

Guidelines as Topic↗
PubMedDate not supplied

Special solutions.

Explore the source record for details and available documents.

Hospitals, Psychiatric↗