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61.
A 57-year-old woman with cutaneous mastocytosis of 23 years duration developed a hyperpigmented abdominal plaque composed of confluent indurated papules that enlarged for a period of 1 year to 12 x 8 cm. Biopsy showed dermal infiltration by closely packed spindle-shaped mast cells, fibroblasts, collagen, and scattered lymphocytes, predominantly T-suppressor cells. Electron microscopy showed close contact between mast cells, fibroblasts, and lymphocytes. Piecemeal mast cell degranulation and extrusion of mast cell granules was seen, with rare mast cell granules in fibroblasts, and collagen fibers in peripheral and perinuclear endoplasmic reticulum of mast cells. the term Fibrous mastocytoma is suggested for this tumor-like dermal fibrosis, possibly induced by lymphokines.  相似文献   
62.
Gastric acidity, atrophic gastritis, and calcium absorption.   总被引:2,自引:0,他引:2  
The deleterious effects of increased gastric pH on calcium absorption from calcium carbonate supplements were observed about 25 years ago. Increasing use of calcium supplements, especially by the elderly, has raised questions about bioavailability from various calcium sources. Decreased gastric acidity is common in the elderly and in patients taking antiulcer medications. A critical review of the available human studies that have investigated the role of gastric acidity in calcium bioavailability suggests that the effects of increased gastric pH are only apparent when poorly soluble calcium salts are taken after an overnight fast. Soluble calcium sources, such as calcium citrate and calcium from milk, are absorbed normally in elderly subjects with atrophic gastritis. Moreover, calcium carbonate, a relatively insoluble calcium salt, is well absorbed in atrophic gastritis patients if administered with a meal. In order to maximize calcium bioavailability, elderly subjects should increase their calcium intakes to at least recommended levels, preferably by increasing milk consumption. When calcium supplements are used to augment dietary calcium sources, a highly soluble source should be of benefit or calcium carbonate may be taken with a meal.  相似文献   
63.
To elucidate the role of catecholamines in attention deficit disorder, the authors conducted an open 8-week trial of L-tyrosine in 12 adults with attention deficit disorder, residual type. Eight showed marked to moderate clinical response in 2 weeks; at 6 weeks these eight developed tolerance, suggesting that L-tyrosine is not useful in attention deficit disorder, residual type.  相似文献   
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In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
67.
R M Syme  C J Wood  H Wong    C H Mody 《Immunology》1997,92(2):194-200
The current studies were performed to determine the contribution of T-cell subsets to lymphocyte proliferation in response to Cryptococcus neoformans, the most common invasive mycosis in acquired immune deficiency syndrome. We demonstrate for the first time that both human CD4 and CD8 cells are activated in response to C. neoformans. Both CD4 and CD8 cells express interleukin-2 receptor alpha (IL-2R alpha) and transferrin receptor and proliferate in response to C, neoformans, however proliferation of CD8 cells was dependent upon CD4 cells. The requirement for CD4 cells was complex, since CD8 enriched cells failed to express mRNA for IL-2, suggesting that CD4-dependent IL-2 production was required for CD8-cell proliferation. However, IL-2 was not sufficient to restore CD8-cell proliferation. These studies provide experimental evidence in humans to support the clinical impression that CD4 cells are important in cryptococcosis, and suggest that the appropriate CD4-derived signals could allow CD8 cells to assist in host defence.  相似文献   
68.
Safety of outpatient tonsillectomy and adenoidectomy   总被引:6,自引:0,他引:6  
Recent changes in reimbursement for tonsillectomy and adenoidectomy have resulted in a large number of these procedures being done on an outpatient basis. There is still considerable controversy, however, as to the safety of this concept. We reviewed the charts of 1000 consecutive patients who underwent these procedures. Three hundred ninety-six procedures were performed as inpatient surgery and 604 were performed as outpatient surgery. Patients were considered as candidates for outpatient surgery if they met specific criteria, such as good overall medical health, no central apnea, normal bleeding history and profile, and had adequate social considerations. The inpatient group included those patients who did not meet the criteria to be outpatients. We compared the complication rates of these two groups with regard to age, type of procedure performed (tonsillectomy, adenoidectomy, adenotonsillectomy), and indication for surgery in order to determine if there was any increased risk of outpatient surgery, despite strict selection criteria. The two groups were similar in their distribution with regards to age, sex, type of procedure, and indication for surgery. The overall complication rate for the entire group was 7.9%, with an 11.8% complication rate for inpatients and 4.1% complications for outpatients. The higher complication rate among the inpatient group is probably a direct result of the selection process because this group included the higher-risk patients. On the basis of these findings, we believe that surgery of the tonsils and adenoids can be performed safely as an outpatient procedure, regardless of age, indication, or procedure, if the candidates for ambulatory surgery are carefully selected by the surgeon.  相似文献   
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