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191.
The most outstanding pathological changes of perinatal babies and children, based on the review of the autopsy files in the 1st Affiliated Hospital of West China University of Medical Sciences, are lymphocytic depletion, and reticuloepithelial cell swelling and/or fusiform malformation in the cortex, while in the medulla apoptosis is more prominent. We suppose that these alterations are due to immaturity of cortical thymocytes, and in the diseased condition, they are easily affected by extraordinary factors, especially the influence of corticosterone inducing acute severe necrosis, so the number of lymphocytes are obviously diminished. But, in the medulla, as intact mature lymphocytes exist, physiological phenomenon such as apoptosis is rather prominent in it. While in the medulla, Hassall's corpuscles have various characteristic changes, such as cornification, calcification, fusion, cystic change and disintegration. Besides, we observed a new alteration in the thymus defined as vacuolization. All the above pathological changes reached the peak in the 28- day group; there after, they might become either worse or better according to the condition of the disease and growth of the body. However, these are still problems to be further studied separately.  相似文献   
192.
The definition, classification, proposed etiologies, diagnosis, and treatment of the premenstrual syndrome (PMS) are discussed, and guidelines for the clinical management of PMS are presented. PMS encompasses a cluster of physical and psychosocial symptoms that recur during each menstrual cycle. Proposed etiologies for the syndrome include a hormonal imbalance between estrogen and progesterone, pyridoxine hydrochloride deficiency, hypoglycemia, excess prostaglandin production, and increased aldosterone concentrations in the luteal phase of the menstrual cycle. Diagnosis of PMS is usually based on a patient's history of recurrent symptoms accompanied by a seven-day, symptom-free period in the first half of the menstrual cycle. Management of PMS is complicated by the difficulty in diagnosing the syndrome and its unclear etiology. If possible, conservative nonpharmacologic treatment should be tried initially; suggested measures include modifications in diet, exercise, substance use, stress factors, rest patterns, and social support. Pharmacologic treatment should be considered when conservative therapies are ineffective or when PMS symptoms are more severe. Although most therapies are empirical, treatment with progesterone, pyridoxine, bromocriptine, or diuretics might prove beneficial. Once the decision is made to initiate drug therapy, the treatment regimen should be individualized and based on the patient's PMS symptom complex. The clinical management of PMS is complicated by the lack of well-designed clinical investigations of proposed treatments. Future research should be directed toward evaluating the efficacy of proposed therapeutic regimens.  相似文献   
193.
High-dose methotrexate (MTX) toxicity is reduced by a non-toxic dose of 5-fluorouracil (FU) when these agents are used in combination. Changes in the hematopoietic system (platelets, erythrocytes, leukocytes, hemoglobin, and hematocrit), ileal tissue, body weight, and mean survival were used as parameters to assess toxicity. For all parameters studied, there were no significant differences between the scheduling of MTX (245 mg/kg) after a priming dose of FU (25 mg/kg), simultaneous MTX and FU, FU alone, and control. However, sequential treatment with MTX followed by FU, and MTX alone resulted in: a marked decrease in the hematopoietic parameters; significant morphological changes in ileal tissue; a reduction of body weight; and increased mortality of animals. Hence, this study suggests that FU, a cytotoxic agent, may protect against MTX toxicity and improve its therapeutic index when FU administration precedes MTX or when these agents are given simultaneously.  相似文献   
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目的 探讨气温对细菌性痢疾发病的影响。方法 应用相关回归统计法和圆形分布法对资料进行研究。结果 菌痢的月平均发病百分构成比与相应年份月平均气温呈正相关(r=0.5099,P<0.01);辖区近10年的平均气温较前10年有所上升,尤其秋冬季与初春月平均气温升高了1℃左右,而菌痢发病高峰时点明显后移(F=11.49,P<0.01),流行高峰期也有后移倾向。结论 气温对菌痢的发病有直接影响,气温升高,菌痢的发病增加,年平均气温升高可导致菌痢的发病高峰时间后移。  相似文献   
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