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81.
Physiological and morphological changes produced by corticotropin-releasing factor (CRF) stimulation in vivo were studied in pituitaries immunocytochemically stained for ACTH. After 48-h ip minipump infusions of 10 or 50 ng/min CRF, serum ACTH levels were increased significantly over values in control groups that included both intact rats and rats exposed to sham abdominal surgery. Correlative morphological changes included a striking increase in corticotrope cell area. This was coupled with an apparent decrease in the percentage of stained cells, probably due to degranulation. The cellular responses were similar to those after adrenalectomy described previously by us and others. Therefore, in a parallel study, additional groups of rats were adrenalectomized and studied 24 and 48 h after the surgery. Even greater changes in serum ACTH, corticotrope cell area, and percentages were observed in the adrenalectomized rats. The difference between the CRF-infused and adrenalectomized groups was probably due to the lack of corticosterone feedback in the latter group. Among the control groups, there were no differences between intact rats and rats exposed to sham abdominal surgery. Rats subjected to sham adrenalectomy, however, showed corticotrope responses similar to those of CRF-infused rats, except that the cells were more densely stained. The present studies thus show dramatic changes in ACTH cell area, extent of staining, and percentages after in vivo CRF stimulation. In all of the experimental groups, an excellent correlation existed between serum ACTH levels and the degree of the morphological changes in the corticotropes.  相似文献   
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Molecular heterogeneity in acute leukemia lineage switch   总被引:1,自引:0,他引:1  
Six cases of acute leukemia that underwent lineage switch from acute lymphocytic leukemia to acute myelogenous leukemia are reported. The mean age of the patients was 24 years, time to conversion was 36 months, and survival after conversion was only 3 months. Of the three cases which showed abnormal metaphases at both diagnosis and conversion, two (cases 2, 5) showed related cytogenetic abnormalities, and the third showed (case 3) independent chromosomal changes. Molecular analysis for immunoglobulin heavy chain and T-cell receptor beta chain genes showed that five of the six cases had rearrangement of at least one of these lymphoid associated genes at conversion to acute myelogenous leukemia. The single case (case 3) in which there were no lymphoid gene rearrangements at conversion was also the only case in which independent karyotypic abnormalities at diagnosis and conversion were demonstrated. Our findings suggest that lineage switch can represent either relapse of the original clone with heterogeneity at the molecular level or the emergence of a second new leukemic clone without molecular heterogeneity.  相似文献   
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Although airbags are designed to save lives and protect victims from serious injuries, airbag deployment can cause unwanted lesions. In this case report, two cases are presented of young women who sustained an important fracture dislocation of the first carpometacarpal joint (CMC I joint) caused by airbag deployment during a car collision.  相似文献   
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We compared the prevalence of hypertension in patients with non–insulin-dependent diabetes mellitus (NIDDM) in referral and primary care practices using definitions of The Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC-V), while controlling for other risk factors such as hypertension, obesity, smoking, and age. Patients (n = 1443) were enrolled consecutively from a large referral practice at the Jackson Diabetes Center and four primary care clinics in the vicinity. Blood pressures were measured at three clinic visits after a 5-min rest in a sitting position using a standard clinical sphygmomanometer. Charts were reviewed to determine diabetes duration, insulin usage, height, weight, smoking history, use of antihypertensive and oral hypoglycemic medications, socioeconomic status, and race. Patients were classified as hypertensive based on JNC-V definitions or if they were on antihypertensive medication. Hypertension was termed uncontrolled if blood pressure was JNC-V Stage 2 or higher while on antihypertensive medication.

Seventy-eight percent of referral clinic and 55% of primary care clinic patients had either JNC-V State 1 or higher hypertension or were on antihypertensive medication. Actual blood pressures indicated that more patients had JNC-V Stage 1 (mild) or higher hypertension in referral compared to primary care clinics (62% versus 48% p = 0.01) but fewer had JNC-V Stage 2 or higher (moderate-severe) hypertension (12% versus 19% p = 0.002). Patients seen in the referral clinic were significantly more likely to have greater age, greater duration of diabetes, higher insulin dosage, longer smoking history, antihypertensive medication, and live outside the metropolitan area. By logistic regression, the odds of hypertension were significantly increased with age (OR 1.51/decade), BMI greater than 27 (OR 2.17), diabetes duration (OR 1.04/year), and insulin dosage (OR 1.74/U/kg). Current smoking and attending a referral clinic were not significantly related. The odds of moderate-severe hypertension were significantly increased with age (OR 1.23/decade), decreased by attending a referral clinic (OR 0.45), and not significantly related to other confounders in the model.

The prevalence of hypertension among patients with NIDDM was higher in referral than primary care clinics. The higher prevalence in the referral practice can be accounted for by the greater severity of associated risk factors in the referral practice patients; however, most patients will be diagnosed and treated for hypertension prior to referral. More patients in the referral practice were on hypertensive medication, which lowered the stage or severity of hypertension but still not to the normal range. The results suggest that the primary detection of hypertension in patients with type II diabetes resides with the primary care physician. Management of hypertension will require both a delineation and acceptance of responsibilities between the primary care physician and diabetes specialists.  相似文献   

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OBJECTIVE: To assess the outcome of children with systemic sclerosis (SSc) and features of polymyositis. METHODS: The charts of 4 children who met the American College of Rheumatology criteria for SSc and had features of polymyositis, as defined by the presence of proximal muscle weakness and elevated serum creatine phosphokinase or aldolase level, were retrospectively reviewed. RESULTS: All children had multivisceral involvement including (1) myocardial perfusion defects in all cases, with mild to severe dilated cardiomyopathy in 3; (2) lung restrictive syndrome in 3; (3) mild to severe esophageal involvement in all cases; and (4) severe intestinal dysfunction in one child. Combination therapy of corticosteroids, methotrexate (MTX), and cyclosporine resulted in improved skin thickness and muscle strength scores in all cases, as well as in lung restrictive syndrome in 2, but was not effective regarding the progression of intestinal malabsorption in one patient, esophageal dysmotility in 3 patients, and dilated cardiomyopathy in 3. Endstage cardiac failure caused 2 deaths. In one child, heart transplantation was performed for the first time in this indication. CONCLUSION: Children with diffuse cutaneous SSc and features of polymyositis are prone to develop severe cardiomyopathy. Combination therapy of corticosteroids, MTX, and cyclosporine seems to be active on muscle, skin, and lung involvement but does not impair progression of esophageal or myocardial dysfunction. Heart transplantation might be considered, as an experimental treatment, in young patients with severe cardiomyopathy and no other irreversible organ damage.  相似文献   
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