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21.
OBJECTIVE: To determine whether transdermal progesterone cream has any effect on vasomotor symptoms, mood, sexual response, cardiovascular lipid levels, or bone mineral metabolic markers. DESIGN: A parallel, double-blind, randomized, placebo-controlled trial comparing the effect of a transdermal cream containing a progesterone (32 mg daily) with a placebo cream. Eighty postmenopausal women in the Menopause Centre at the Royal Hospital for Women, Sydney, were randomly allocated to receive either the progesterone cream or the placebo. They were evaluated using the Greene Climacteric Scale and the Menopause Quality of Life Questionnaire, as well as blood analysis for lipids and bone markers over a period of 12 weeks. Women were prescribed a cream containing either progesterone at 32 mg daily or a placebo cream for a period of 12 weeks. RESULTS: There was no detectable change in vasomotor symptoms, mood characteristics, or sexual feelings, nor was there any change in blood lipid levels or in bone metabolic markers, despite a slight elevation of blood progesterone levels. CONCLUSION: The use of the transdermal route to administer progesterone at 32 mg daily does not seem to allow sufficient hormone to enter the body to achieve a biological effect on lipid levels, bone mineral metabolic markers, vasomotor symptoms, or moods.  相似文献   
22.
This report describes an adult male with a partial trisomy 6p(p211-pter) and a partial monosomy 9p(9p24-pter) resulting from a de novo unbalanced translocation. This patient does not show the classical featured of the 9p partial monosomy syndrome, thus disputing the claim of Hoo et al. (1982) that 9p24 is the critical segment for the monosomy syndrome. Partial trisomy for 6p has only been previously reported in children. In addition to the chromosomal anomalies, the patient has autosomal recessive spinal muscular atrophy with a different age of onset than two affected sibs. Finally, he shows unusual audiologic and ophthalmologic signs nor previously reported as part of the 9p monosomy or 6p trisomy syndromes.  相似文献   
23.
Adjuvant Arthritis (AA) can be induced by passive transfer of a T cell clone (A2b) derived from arthritic rats, specific for Heat Shock Protein 60, HSP60 176-190. Furthermore, a crucial role for T cells with HSP60 176-190 specificity in AA was shown by induction of tolerance using HSP60 176-190 or by immunization with an altered peptide ligand based on the same sequence. To study clonal expansion of A2b-like T cells during AA and to determine their role in AA induction, we generated a clonotypic antibody, 16C4, specific for the TCR of the A2b T cell clone (TCR AV11S1/BV18). This antibody stained A2b T cells in flow cytometry experiments, induced proliferation of A2b cells when fixed on a solid support, and inhibited antigen-induced A2b proliferation when added in solution. A2b-like T cells were detected in a low frequency in lymphoid organs of arthritic rats. Thus, as in vivo administration of 16C4 did not inhibit AA, cells containing the determinant recognized by 16C4 are possibly not the sole contributors to AA development. Furthermore, epitope specific interventions by antigen administration may be possible even in cases where the epitope specific T cell clonotype is of low frequency.  相似文献   
24.
A number of noninvasive fiber optic optical technologies are under development for real-time diagnosis of neoplasia. We investigate how the light scattering properties of cervical cells are affected by changes in nuclear morphology, DNA content, and chromatin texture, which occur during neoplastic progression. We used a Cyto-Savant computer-assisted image analysis system to acquire quantitative nuclear features measurements from 122 Feulgen-thionin-stained histopathologic sections of cervical tissue. A subset of the measured nuclear features was incorporated into a finite-difference time-domain (FDTD) model of cellular light scattering. The magnitude and angular distribution of scattered light was calculated for cervical cells as a function of pathologic grade. The nuclear atypia strongly affected light scattering properties. The increased size and elevated DNA content of nuclei in high-grade lesions caused the most significant changes in scattering intensity. The spatial dimensions of chromatin texture features and the amplitude of refractive index fluctuations within the nucleus impacted both the angular distribution of scattering angles and the total amount of scattered light. Cellular scattering is sensitive to changes in nuclear morphology that accompany neoplastic progression. Understanding the quantitative relationships between nuclear features and scattering properties will aid in the development of noninvasive optical technologies for detection of precancerous conditions.  相似文献   
25.
Separation anxiety: the etiology of nondisjunction in flies and people   总被引:8,自引:0,他引:8  
Two new studies examine the recombinational history of humanchromosomes that nondisjoin at the first meiotic division infemales. Our analysis of these studies suggests two possibleetiologies of nondisjunction in terms of well-understood propertiesof chromosome mechanics. For both the X chromosome and for chromosome21, 60–70% of nondisjoined chromosomes are derived fromchlasmate bivalents, many of which display unusual patternsof exchange. The patterns of exchange and nondisjunction observedfor human chromosome 21 parallel those exhibited by a mutationin Drosophila that impairs spindle assembly and function. Basedon these similarities, we propose that nondisjunction of chromosome21 in human females results from an age-dependent loss of spindle-formingability. The recombinational histories of nondisjoining humanX chromosomes are quite different from those of chromosome 21,but rather parallel those obtained for spontaneous nondisjunctionin Drosophila females. The data for X chromosome disjunctionin both species can be explained by a model in which nondisjunctionis the consequence of the age-dependent movement of transposableelements. According to this model, nondisjunction is explainedas the consequence of the repair of transposon-induced breaksin the DNA. Both models provide reasonable alternatives to biologicallyimplausible explanations such as the ‘production linehypothesis’.  相似文献   
26.
27.
Recognition of self protein epitopes, apart from those engaged in idiotypic network interactions and MHC restriction, is probably a physiological event in the normal functioning immune system. Furthermore T and B cells recognizing self antigens can be easily cloned from healthy individuals and sometimes be shown to confer autoimmune disease by passive transfer in the experimental situation. The issue is how potentially autoaggressive cells can become activated and how such activity can be contained safely. Experimentally, autoimmune disease can be evoked by immunization with autoantigens (encephalomyelitis, thyroiditis etc.) or with foreign antigens that feature antigenic relationships with self antigens (adjuvant arthritis). In both situations transfer of disease has been shown with cloned T cells of a single specificity. In addition, specific control of disease using the same cloned T cells has been achieved. Adjuvant arthritis has been illustrative in these respects. By means of specificity analysis of cloned T cells, a 65 kD heat shock protein of mycobacteria was identified as crucial in the disease. Immunization with this antigen has been found to prevent the development of disease, including forms elicited without mycobacterial involvement. Furthermore, vigorous immunological responses to HSP65 were found both in experimental animals and also in humans as a consequence of exposition to various infectious organisms. By their conserved nature HSPs have ample potential for dangerous mimicry. Recent evidence accumulated suggesting that the same HPS65 may be crucial in human chronic arthritis as well. Therefore it is hoped that extrapolation of the experimental findings to the human situation will help the development of specific means, either T cells or antigens, to control spontaneous autoimmune arthritis in man.  相似文献   
28.
A phase II study of ifosfamide in children with recurrent solid tumours   总被引:3,自引:0,他引:3  
Summary Twenty children with recurrent or unresponsive tumours (10 Wilms', 3 rhabdomyosarcoma, 4 Ewings's, 1 osteosarcoma, 1 hepatoblastoma, 1 hepatoma) and one untreated patient with renal carcinoma were given ifosfamide as a 24-h infusion (5 mg/m2), with mesna as uroprotective. The number of courses ranged from 1 to 13 (median 3), and the interval between them was 2–3 weeks. Sixteen of these patients had previously received cyclophosphamide. Complete clinical responses were seen in 3 cases (2 Wilms' and 1 Ewing's) and lasted 5, 7, and 9 months. Partial responses were seen in 3 instances, mixed response or stable disease in 4, and progressive disease in 11. Treatment was well tolerated in most patients, with no cystitis or severe myelosuppression, but 2 children developed transient neurological symptoms and 1 became hypertensive. Nausea and vomiting were controlled by high-dose dexamethasone in most children.Plasma ifosfamide levels were estimated by means of gas-liquid chromatography in 10 patients. Peak concentrations ranged from 38 to 125 g/ml (median 80). The elimination half-life, at 2.5–5.2 h (median 3.2) was shorter than previously reported in adults.Future studies should test the possibility that ifosfamide-containing combination chemotherapy may be more effective than the regimens, usually including cyclophosphamide, that are currently used as front-line treatment of embryonal and Ewing's sarcoma.  相似文献   
29.
Quality of Life Research - This study aimed to investigate changes over time in quality of life, perceived stress, and serious psychological distress for individuals diagnosed with COVID-19 in an...  相似文献   
30.
Annals of Surgical Oncology - Locally advanced pancreatic cancer (LAPC) is a challenging disease to treat. There is consensus that systemic chemotherapy should be the first line of therapy for most...  相似文献   
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