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31.
In this experimental study, the usefulness of a new radiotracer, Tc-99m pyridoxal-phenylalanine ("Tc-PPh"), is evaluated as a hepatobiliary imaging agent, and results are compared with those of conventional cholangiography. In the presence of a normal biliary tree or in cholelithiasis, information derived from conventional cholangiography is of better quality. The radiotracer technique, however, is very useful for the demonstration of cholopeptic bypass procedures, even in the presence of jaundice, and also in cases of intraperitoneal bile leakage.  相似文献   
32.
BACKGROUND: Small series and retrospective studies have suggested that treatment with gemcitabine may be associated with pulmonary toxicity. However, a prospective evaluation of cancer patients treated with gemcitabine-based chemotherapy without neoplastic involvement of the thorax and without administration of radiotherapy has not been performed. PATIENTS AND METHODS: To investigate this issue, 41 consecutive patients receiving gemcitabine and carboplatin underwent prospective evaluation of lung function, which included pulmonary symptoms, pulmonary function tests, arterial blood gases and radiographic studies. Assessment was performed before and after completion of chemotherapy in all patients. Patients with a substantial decline in diffusion capacity for carbon monoxide (DLCO), defined as a drop of > or = 20%, were reassessed 2 months later. RESULTS: After chemotherapy, there were no significant changes in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, alveolar volume or total lung capacity. In contrast, there was a significant decline in DLCO (73 +/- 22 versus 67 +/- 24% predicted; P = 0.017) and in carbon monoxide transfer coefficient (KCO) (89 +/- 24 versus 80 +/- 24% predicted; P = 0.004). Arterial blood gases did not change following treatment. Ten of the 41 patients (24%) exhibited a substantial decline in DLCO, which, however, recovered within 2 months (DLCO at baseline, immediately after therapy and at 2 months after completion of treatment, 84 +/- 14, 58 +/- 16 and 77 +/- 17% predicted, respectively; P < 0.001; baseline DLCO versus DLCO at 2 months, P > 0.05). Four of the 41 patients (10%) experienced dyspnea, which was self-limiting, with the exception of one patient who developed interstitial lung fibrosis. Among the various risk factors examined, older age, female gender and lower baseline DLCO were associated with more profound changes in DLCO post-treatment. CONCLUSIONS: This prospective analysis showed that the combination of gemcitabine and carboplatin induces a significant, but reversible, decrease in diffusion capacity, which is mostly asymptomatic. Thus, this regimen is safe as regards clinically significant lung toxicity.  相似文献   
33.
Tumors of the spermatic cord are very rare, and approximately one half of all primary spermatic cord tumors are malignant. We report the presentation and treatment of an adult (36-year-old) patient with a mixed germ cell tumor that originated in the spermatic cord. No similar cases of mixed tumors of the spermatic cord in adults have been reported.  相似文献   
34.
An indirect fluorescent antibody test for Bartonella henselae, B quintana, and B elizabethae was performed in all 18 children who presented to our paediatric outpatient clinic with cat scratch disease over a six year period. Serum samples were taken on admission, after 15 days, and after six months. Diagnosis was confirmed in 15 patients (83%) and was based on seroconversion or a fourfold change of the antibody titre to B henselae in 12 patients and on a single high titre (>128) in three patients. Lymphadenopathy was present in all patients, erythema nodosum in one, osteomyelitis in one, hepatitis in one, transverse myelitis in one, and liver or spleen granulomata, or both, in three patients. Cat scratch disease developed in autumn or winter in 12 patients. All had a history of physical contact with a cat. Our study shows that our clinical suspicion was accurate in the diagnosis of cat scratch disease in a high percentage of patients presenting to a hospital and that indirect fluorescent antibody testing for B henselae is a useful diagnostic tool.

  相似文献   
35.
Case-control methodology was used to evaluate the significance of vascularity in small breast carcinomas with regard to the presence or absence of axillary lymph node metastases. Vascularity was assessed in 32 axillary node positive primary breast tumours (LN+ve) less than 2 cm in size and compared with 56 control axillary node negative primary tumours (LN–ve), which were matched for histological type and grade and tumour size. This study design employed computer-assisted video analysis (CAVA) to assess the total blood vessel perimeter (BVP), total blood vessel area (BVA), and total blood vessel density (BVD) throughout a tissue section that encompassed an entire cross section of the tumour and its immediate periphery. The BVA and BVD in these tumours were not significantly different between LN+ve and LN–ve groups. The LN–ve carcinomas had, on average, a significantly (P < 0.05) higher total BVP (3355 µm/mm2) than LN+ve tumours (2771 µm/mm2). 'Hot spot' areas were also independently assessed by two pathologists and the same areas measured by CAVA. A strong correlation (P < 0.001) between the two methods of assessment of BVD of the neovascular 'hot spots' was found; however, no association with axillary lymph node metastasis was found using either method of assessment. In conclusion, vascularity assessed by either blood vessel density or blood vessel size in primary invasive breast cancers less than 2 cm in diameter showed no association with axillary lymph node metastasis; in fact a negative association was found with total BVP of whole tumour sections and BVD in 'hot spots' using CAVA. Further, this study has established a computer-assisted method of quantifying vascularity in solid neoplasms and is a positive step towards a standardised approach to this diverse and methodologically variable area.  相似文献   
36.
Purpose: To evaluate the efficacy and safety of the docetaxel-cisplatin combination in patients with advanced non-small-cell lung cancer (NSCLC).Patients and methods: Chemotherapy-naïve patients with histologically confirmed, measurable stage IIIB or IV NSCLC, a World Health Organization (WHO) performance status of 0–2 and adequate bone marrow, renal, hepatic and cardiac function were eligible for the study. Patients received docetaxel (100 mg/m2) as an one-hour infusion on day 1 and cisplatin (80 mg/m2) as a 30-min infusion with appropriate hydration on day 2. Granulocyte colony-stimulating factor (G-CSF; 150 µg/m2 , SC) was given on days 3 to 13. Treatment was repeated every three weeks.Results: Fifty-three patients were enrolled (28 with stage IIIB and 25 with stage IV). One complete and 23 partial responses were observed (overall response rate (OR): 45%; 95% CI: 34.1%–61.8%). The response rate was 57% and 32% in patients with stages IIIB and IV disease (P = NS). The median time to progression was 36 weeks and the median survival 48 weeks; the one-year survival was 48%. Grade 3–4 neutropenia occurred in 23 patients, 15 of whom were hospitalized for neutropenic fever; two patients died of sepsis. Grade 2 neurotoxicity was observed in six patients and grade 3 in five patients; grade 3 fatigue occurred in seven patients, grade 3–4 mucositis in four patients and grade 3–4 diarrhea in six patients. Mild allergic reactions and oedema were observed in five and four patients, respectively. The median dose intensity was 30 mg/m2 /week for docetaxel and 24 mg/m2 /week for cisplatin, corresponding to 91% and 89% of the specified protocol doses, respectively.Conclusions: The docetaxel–cisplatin combination is an active regimen in advanced NSCLC, but hematologic toxicity remains high despite the prophylactic use of G-CSF.  相似文献   
37.
OBJECTIVE: Valve related factors and patient related factors are responsible for calcification of valvular bioprostheses. Recent studies showed different donor and recipient species have different influences on the total calcification rate of bioprostheses. This study was performed to evaluate and compare Kangaroo aortic valve leaflets with porcine aortic valve leaflets. Experimental design. Prospective study. Setting. Cardio-thoracic experimental research of a university department. MATERIALS AND METHODS: Glutaraldehyde-fixed Kangaroo and porcine valve leaflets were evaluated in vitro according to valve geometry (internal diameter and leaflet thickness), morphology (light and electron microscopy) and tensile strength. In vivo evaluation consisted of implantation in a rat model for 8 weeks, Von Kossa stain for calcium and atomic absorption spectrophotometry for total extractable calcium content. RESULTS: Kangaroo valves indicated a smaller internal valve diameter as well as a thinner valve leaflet (p<0.01, ANOVA) at corresponding body weight, less proteoglycan spicules in the fibrosa, increased elasticity (p<0.05) and low calcification potential (p<0.01, confidence interval 95%). CONCLUSIONS: Kangaroo aortic valve leaflets have different valvular qualities compared to porcine valve tissue. Kangaroo valve leaflets are significantly superior to porcine valve leaflets as far as calcification is concerned. These results are encouraging and suggest further in vivo evaluation in a larger animal model before clinical application can be considered.  相似文献   
38.
PURPOSE: To quantitate the individual levels of melphalan-induced DNA damage formation and repair in vivo and to search for possible correlations with clinical outcome in patients with multiple myeloma (MM). PATIENTS AND METHODS: The formation and subsequent repair of DNA damage (monoadducts and interstrand cross-links) in the p53 tumor-suppressor gene, the proto-oncogene N-ras, and the housekeeping gene beta-actin during the first 24 hours after treatment with high-dose melphalan (HDM; 200 mg/m2) supported by autologous blood stem-cell transplantation (ABSCT) was measured in blood leukocytes of 26 patients with MM. The peak DNA adduct levels, the total amount of adducts over time, and the rate of adducts repair in each gene were correlated with response and time to progression after HDM. RESULTS: The levels of gene-specific DNA damage formation and the individual repairing capacity varied up to 16-fold among patients, indicating that the melphalan-induced biologic effect in vivo is highly individualized. A significantly greater DNA damage and a slower rate of repair in p53 for all end points under study were found in patients who achieved tumor reduction compared with nonresponding patients. Furthermore, longer progression-free survival correlated with increased peak monoadduct levels in the p53 gene (P = .032). CONCLUSION: Increased DNA damage and slower repairing capacity in the p53 gene from blood leukocytes after HDM correlate with improved outcome of patients with MM who undergo ABSCT. These results suggest that quantitation of such biologic end points may identify patients who are more likely to benefit from this procedure.  相似文献   
39.
PURPOSE: Osteonecrosis of the jaw (ONJ) has been associated recently with the use of pamidronate and zoledronic acid. We studied the incidence, characteristics, and risk factors for the development of ONJ among patients treated with bisphosphonates for bone metastases. PATIENTS AND METHODS: ONJ was assessed prospectively since July 2003. The first bisphosphonate treatment among patients with ONJ was administered in 1997. Two hundred fifty-two patients who received bisphosphonates since January 1997 were included in this analysis. RESULTS: Seventeen patients (6.7%) developed ONJ: 11 of 111 (9.9%) with multiple myeloma, two of 70 (2.9%) with breast cancer, three of 46 (6.5%) with prostate cancer, and one of 25 (4%) with other neoplasms (P = .289). The median number of treatment cycles and time of exposure to bisphosphonates were 35 infusions and 39.3 months for patients with ONJ compared with 15 infusions (P < .001) and 19 months (P = .001), respectively, for patients with no ONJ. The incidence of ONJ increased with time to exposure from 1.5% among patients treated for 4 to 12 months to 7.7% for treatment of 37 to 48 months. The cumulative hazard was significantly higher with zoledronic acid compared with pamidronate alone or pamidronate and zoledronic acid sequentially (P < .001). All but two patients with ONJ had a history of dental procedures within the last year or use of dentures. CONCLUSION: The use of bisphosphonates seems to be associated with the development of ONJ. Length of exposure seems to be the most important risk factor for this complication. The type of bisphosphonate may play a role and previous dental procedures may be a precipitating factor.  相似文献   
40.
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