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51.
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
52.
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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In an attempt to construct bispecific monoclonal antibodies (bimAbs) able to target cytotoxic T lymphocytes against human hepatoma cells, an HGPRT-deficient mutant of the Hepama-6 hybridoma, which produces an antihuman-hepatoma mAb, was directly fused with splenocytes from Balb/C mice immunized by a polyclonal cytotoxic T-cell line. Hybrid hybridomas were selected in HAT medium, and their supernatants were directly screened for the ability to induce IL-2-cultured cytotoxic T lymphocytes to kill hepatoma cells in a 51Cr-release assay. The selected hybrid hybridoma, termed DQ-33, secretes a bimAb, which reacts with a CD3-associated determinant. When resting peripheral-blood lymphocytes were used as effector cells, virtually no cytolytic activity could be induced by DQ-33, whereas phytohemagglutinin-activated lymphocytes that had been expanded in vitro in IL-2-containing medium could be efficiently targeted against hepatoma cells. Targeting by DQ-33 bimAb was analyzed on different subsets of IL-2-cultured lymphocytes. It was evident that CD+4-8+ TCR alpha/beta+ and CD3+4-8-TCR gamma/delta+ lymphocytes were efficiently induced by bimAb to lyse human hepatoma cells, whereas no induction of cytolysis could be observed when CD3 + 4 + 8-TCR alpha/beta+ cells were used as effectors. DQ-33 bimAb was also able to induce lymphokine secretion (IL-2, GM-CSF and TNF-alpha) by all the different subsets of lymphocytes analyzed in the presence of target cells expressing the relevant antigen, independent of the expression of cytolytic activity. 相似文献
60.
61 patients with cerebellar hemorrhage were studied. The age at onset ranged from 15 to 84 years with a mean of 57.4 years. 49 cases were treated conservatively and 12 surgically and the mortality rates of the two groups were 32.5% and 25% respectively. Based on this study, it is suggested that the clinical and CT indications of surgical treatment of hematoma are as follows; Severe disturbance of consciousness; Bilateral eyeball fixation; Volume of hematoma over 10 ml; Size of hematoma over 4 cm in diameter; Marked acute obstructive hydrocephalus; Compression of cisterna ambieus and quadrigeminus. 相似文献