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Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin. Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were treated with doxorubicin 60 mg/m2, three patients were treated at 90 mg/m2, and five patients received 120 mg/m2. A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters before return of the blood to the systemic circulation. Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was 120 mg/m2. Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will allow use of higher doses of chemotherapeutic agents to treat HCC. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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The frequency properties of arterial beds in organs were studied by temporarily ligating the renal, the gastric, the splenic or the superior mesenteric arteries of rats. Blood-pressure waves of the tail arteries were recorded before and during the ligations, and were analysed by Fourier's transformation. Their frequency spectra have been found to change profiles following specific patterns with the ligations of different arteries. The results were significant with regard to the frequency selectivities of the organic arterial beds. Such frequency properties can be clearly explained when the circulation system is viewed as an electrical circuit network in which the organic arterial beds work as filters.  相似文献   
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The current concept of breast cancer treatment arises from Fisher's theory that operable breast cancer has distant micrometastasis at its very early stages. Since it is the presence of systemic diseases or micrometastasis that determines the final outcome, variation in local treatment would not affect survival. Fisher's theory led to a change in local treatment, from Halsted's radical mastectomy to breast-conserving therapy (BCT), and the introduction of adjuvant systemic treatment. As part of the job of surgery is replaced by radiation therapy in local control, the efficacy and side effects of radiation should be carefully monitored. The recently published results of 20-year follow-up in 2 important studies confirm that BCT achieves equal survival compared to mastectomy in women with early breast cancers, even after all causes of mortality have been considered. The introduction of sentinel lymph node biopsy has further decreased the adverse impact of breast cancer treatment on women. As variation in local control does not affect survival, more efforts are being put into developing adjuvant systemic treatment with curative intent. Adjuvant chemotherapy has been demonstrated to substantially affect the survival of women with early breast cancers. It is now apparent from numerous studies that adjuvant therapy improves survival in all subgroups of women with early breast cancer, although the absolute benefit varies depending on axillary lymph node status, tumor size, and other prognostic factors. This article reviews recent advances in the management of primary breast cancer, including: long-term follow-up after BCT; side effects of radiation therapy in BCT; post-mastectomy radiotherapy; sentinel node biopsy; adjuvant hormone therapy; and chemotherapy, including new strategies such as the incorporation of taxanes, dose-dense chemotherapy schedules, and the use of aromatase inhibitors in place of, or in addition to, tamoxifen.  相似文献   
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OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
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We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1, 2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs. Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg, i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye, was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays little or no role in early airway responses following antigen challenge. Received: 29 April 1996 / Accepted: 10 October 1996  相似文献   
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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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The antigen-coding region of a 4.2-kb PstI fragment of Chlamydia pneumoniae (pLC3), which encodes a 75-kDa immunoreactive protein recognized during human C. pneumoniae infection, was localized to a 2.0-kb EcoRI fragment. This subclone expressed an immunoreactive fusion protein of ca. 82 kDa. Nucleotide sequence analysis of the C. pneumoniae gene revealed that it consisted of a 1,980-base open reading frame with an inferred 71,550-Da protein of 660 amino acids. Putative Escherichia coli-like promoters and a ribosomal binding site were located in the 5' upstream region, and an 11-base dyad forming a stable stem-loop structure following two in-frame stop codons was identified. The C. pneumoniae 75-kDa protein is a member of the hsp70 family of heat shock proteins and has 87% amino acid similarity with the Chlamydia trachomatis protein.  相似文献   
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