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991.
The Sheffield Trophoblastic Disease Centre treats about 25 patients with persistent trophoblastic disease each year. A total of 75% of patients are classified as low risk according to the Charing Cross Hospital prognostic scoring system and receive methotrexate (MTX) 50 mg, i.m., on days 1, 3, 5, 7 with folinic acid 7.5 mg orally 24 h after each methotrexate injection. There is a 7-day rest between treatment cycles. Remission is achieved in 85% of cases. Approximately 20% of patients experienced pleuritic chest pain and dyspnoea. We have evaluated prospectively lung function in 16 low-risk patients receiving methotrexate. All patients had pulmonary function tests [spirometry-forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR), and transfer factor - TLCO, kCO] performed before and after completed treatment. A mean of 7.5 cycles of MTX were administered (range 4-11). There was a significant reduction in the mean TLCO (mean pre/post 8.15/7.38 mmol min-1 kPa-1, P = 0.01), but there were no other statistically significant changes. Three patients experienced respiratory symptoms and were found to have a 39%, 28%, and 11% reduction in TLCO from baseline, improving on follow up to pretreatment levels. Low-dose MTX is an effective therapy but may cause troublesome pulmonary toxicity.  相似文献   
992.
OBJECTIVE: To review the occurrence characteristics of and clinical repair experience with brain herniation in to the middle ear and mastoid from 1970-1995. STUDY DESIGN: Retrospective chart/case review. SETTING: Private Otology/Neurotology referral practice. PATIENTS: Thirty-five patients with temporal bone brain herniation diagnosed and treated from 1970-1995. INTERVENTION: Diagnosis confirmed by CT and/or MRI. Treatment was surgical. MAIN OUTCOME MEASURES: Success of surgical repair of the problem in a large experience with follow-up of up to 180 months (mean, 48.7 months). RESULTS: Diagnosis is most effectively made by both (computed tomography (CT) and magnetic resonance imaging (MRI). In this series diagnosis was accurate in 89% with MRI. Primary repair was successful in all but three patients, two of whom required a second repair. One was unreconstructable. CONCLUSIONS: Temporal bone encephaloceles occur after ear surgery and in chronic otitis media. Prompt and effective surgical repair is successful and integral to complication avoidance.  相似文献   
993.
OBJECTIVE: Depressive personality disorder was introduced into DSM-IV's appendix amid controversy. While that disorder appears to be a reliable and valid one, the authors offer new data about its relationship to major depression, dysthymic disorder, and other personality disorders. METHOD: The authors assessed 54 subjects with early-onset, long-standing mild depressive features for depressive personality disorder, axis I and axis II disorders, family history, and treatment history; they conducted follow-up interviews 1 year after the baseline assessment. Subjects with (N=30) and without (N=24) depressive personality disorder were characterized and compared in terms of those variables. RESULTS: Although depressive personality disorder and dysthymia co-occurred in some subjects, 63% of subjects with depressive personality disorder did not have dysthymia, and 60% did not have current major depression. Although subjects with depressive personality disorder were more likely than the mood disorder comparison group to have another personality disorder, 40% had no such disorder. Contrary to study hypotheses, mood disorder was not more common in first-degree relatives of subjects with depressive personality disorder than in relatives of the comparison group. Subjects with and without depressive personality disorder had similar rates of past treatment with medication and psychotherapy; however, the duration of psychotherapy was significantly longer for subjects with than for those without depressive personality. The depressive personality diagnosis was relatively stable over the 1-year follow-up period. CONCLUSIONS: Depressive personality disorder appears to be a relatively stable condition with incomplete overlap with axis I mood disorders and personality disorders. Further studies are needed to better characterize its treatment response and relationship to axis I mood disorders.  相似文献   
994.
BACKGROUND: A significant percentage of patients with refractory germ cell tumors will not respond to standard salvage regimens. Thus there is a need for new active agents. Paclitaxel has demonstrated activity against a variety of solid tumors in both laboratory and clinical studies. METHODS: Eighteen patients with refractory germ cell tumors who failed initial cisplatin-based chemotherapy and a maximum of 2 salvage regimens were enrolled into a Phase II trial of paclitaxel at a dose of 170 mg/m2 by intravenous infusion over 24 hours every 21 days without growth factor support. The median age of the patients was 32.5 years (range, 18-49 years). The testis was the primary site of tumor for 13 patients (72%) and the tumor was extragonadal in 5 patients (28%). Six patients (33%) were late recurrences. Twelve patients (67%) had > or = 2 metastatic sites. The median number of previous chemotherapy cycles was six (range, four to nine). Three patients (17%) previously had undergone autologous bone marrow transplantation. RESULTS: Two patients (11%) responded to paclitaxel. Major toxicities were Grade 3-4 neutropenia (55% of patients) and Grade 3-4 neurotoxicity (2 patients). Neutropenic fever occurred in 3 patients (17%). CONCLUSIONS: Paclitaxel demonstrated minimal activity in heavily pretreated patients with multiple, poor risk clinical features. These results in part may be due to the unfavorable characteristics of the patients in the current study, specifically the high percentage of patients with late recurrences and extragonadal primary tumors, both of which are known to respond poorly to salvage therapy. Other trials with different patient populations and doses of paclitaxel reported response rates ranging from 13.3%-26%. The role of paclitaxel in the treatment of patients with refractory germ cell tumors remains to be defined in future studies.  相似文献   
995.
Annexins comprise a family of proteins that exhibit a Ca2+-dependent binding to phospholipid membranes that is possibly relevant to their in vivo function. Although substantial structural information about the ternary (protein/lipid/Ca2+) interaction in bulk phases has been derived from a variety of techniques, little is known about the temporal and spatial organization of ternary monolayer films. The effect of Ca2+ on the interactions between annexin V (AxV) and anionic DMPA monolayers was therefore investigated using three complementary approaches: surface pressure measurements, infrared reflection-absorption spectroscopy (IRRAS), and Brewster angle microscopy (BAM). In the absence of Ca2+, the injection of AxV into an aqueous subphase beneath a DMPA monolayer initially in a liquid expanded phase produced BAM images revealing domains of protein presumably surrounded by liquid-expanded lipid. The protein-rich areas expanded with time, resulting in reduction of the area available to the DMPA and, eventually, in the formation of condensed lipid domains in spatial regions separate from the protein film. There was thus no evidence for a specific binary AxV/lipid interaction. In contrast, injection of AxV/Ca2+ at a total Ca2+ concentration of 10 microM beneath a DMPA monolayer revealed no pure protein domains, but rather the slow formation of pinhead structures. This was followed by slow (>2 h) rigidification of the whole film accompanied by an increase in surface pressure, and connection of solid domains to form a structure resembling strings of pearls. These changes were characteristic of this specific ternary interaction. Acyl chain conformational order of the DMPA, as measured by nu(sym)CH2 near 2850 cm(-1), was increased in both the AxV/DMPA and AxV/DMPA/Ca2+ monolayers compared to either DMPA monolayers alone or in the presence of Ca2+. The utility of the combined structural and temporal information derived from these three complementary techniques for the study of monolayers in situ at the air/water interface is evident from this work.  相似文献   
996.
Intravascular administration of iodinated contrast media to patients who are receiving metformin, an oral antidiabetic agent, can result in lactic acidosis. However, this rare complication occurs only if the contrast medium causes renal failure, and the patient continues to take metformin in the presence of renal failure. Because metformin is excreted primarily by the kidneys, continued intake of metformin after the onset of renal failure results in a toxic accumulation of this drug and subsequent lactic acidosis. To avoid this complication, metformin must be withheld after the administration of the contrast agent for 48 hours, during which the contrast-induced renal failure becomes clinically apparent. If renal function is normal at 48 hours, the metformin can be restarted. There is no scientific justification for withholding metformin for 48 hours before administration of the contrast medium, as currently recommended in the package insert. The authors review the pharmacology of metformin and present a departmental policy for managing patients with diabetes who receive metformin and who require intravascular administration of iodinated contrast media.  相似文献   
997.
To assess the tumor targeting, safety, and efficacy of monoclonal antibody 131I-labeled CC49 in patients with androgen-independent prostate cancer, 16 patients received 75 mCi/m2 of the radiolabeled antibody after 7 days of IFN-gamma pretreatment. Sequential tumor biopsies in three patients showed a median 5-fold (range, 2-6-fold) increase in the proportion of cells staining positively for the TAG-72 antigen, whereas one showed a decrease in staining. Fourteen patients received 131I-labeled CC49, whereas 2 showed a disease-related decrease in performance status, precluding antibody treatment. The antibody localized to sites of metastatic androgen-independent prostate cancer in 86% (12 of 14; 95% confidence interval, 57-95%) of cases. Both osseous and extraosseous sites were visualized, and in six (42%) patients, more areas were visible when the radioimmunoconjugate was used than were apparent when conventional scanning techniques were used. The localization of the conjugate in the marrow cavity was usually a site not visualized by the radionuclide bone scan, in which the isotope localizes primarily to the tumor-bone interface. The dose-limiting toxicity was thrombocytopenia because five (36%) patients showed grade IV and seven (50%) showed grade III effects. In addition, six (42%) patients, four of whom were hospitalized, showed a flare in baseline pain, and four showed a decrease in pain. No patient showed a >50% decline in prostate-specific antigen, although radionuclide bone scans remained stable in four cases for a median of 4 months. The results are consistent with dosimetry estimates showing that the delivered dose to tumor was subtherapeutic and suggest that approaches that exclusively target the bone tumor interface or the marrow stroma may be unable to completely eradicate disease in the marrow cavity. For CC49, improving outcomes would require repetitive dosing, which was precluded by the rapid development of a human antimouse antibody response.  相似文献   
998.
Previous studies have demonstrated that oxygen consumption and fat oxidation remain elevated in the postexercise period. The purpose of this study was to determine whether malonyl-CoA, an inhibitor of fatty acid oxidation, remains depressed in muscle after exercise. Rats were sprinted for 5 min (40 m/min, 5% grade) or run for 30 min (21 m/min, 15% grade). Red quadriceps malonyl-CoA returned to resting values by 90 min postexercise in the sprinting rats and remained significantly lower at least 90 min postexercise in the 30-min exercise group. AMP-activated protein kinase activity remained significantly elevated (P < 0.05) for 10 min after exercise in both groups. The most rapid rate of glycogen repletion was in the first 30 min postexercise. The respiratory exchange ratio decreased from a nonexercise value of 0.87 +/- 0.01 to an average 0.82 +/- 0.01 during the 90-min period after 30 min of exercise. Thus muscle malonyl-CoA remains depressed and fat oxidation is elevated for relatively prolonged periods after a single bout of exercise. This may allow fat oxidation to contribute more to muscle energy requirements, thus leaving more glucose for replenishment of muscle glycogen.  相似文献   
999.
OBJECTIVE: We retrospectively reviewed five pathologically proven cases of diffuse cavernous hemangioma of the rectosigmoid colon to define the MR imaging features of this entity. CONCLUSION: Diffuse cavernous hemangioma of the rectosigmoid colon is revealed as rectosigmoid wall thickening with high signal intensity on T2-weighted MR images. Such wall thickening is associated with abnormal perirectal fat. The extent of bowel involvement and extrarectal locations are well shown on T2-weighted MR images.  相似文献   
1000.
Approximately half the women with the polycystic ovary syndrome (PCOS) are obese or overweight. Obesity and body fat distribution have independent roles in the development of hyperandrogenism in PCOS. Most obese and normal weight PCOS are insulin resistant and hyperinsulinemic. Moreover, a significant positive correlation exists between the degree of hyperandrogenism and that of hyperinsulinism. The pathogenetic role of obesity may involve different mechanisms, the major one being the hyperinsulemic state, since insulin is capable of stimulating ovarian androgen secretion and controlling androgen metabolism and transport in peripheral tissues. Abdominal body fat distribution in obese women with PCOS amplifies the degree of hyperandrogenism and related clinical symptoms and signs. Both loss of body weight and/or the reduction of the degree of hyperinsuliemia, induced by diet or insulin-sensitizing drugs, have important effects, since they reduce blood androgen levels and can improve ovulation and clinical signs of hyperandrogenism.  相似文献   
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