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41.
An in vitro assay, which evaluates drug effect on 3H-thymidine incorporation, was used to investigate the absolute and relative activities of cisplatin (DDP), carboplatin (CBDCA) and iproplatin (CHIP) on 317 specimens from untreated tumors, including breast and ovarian cancers and malignant melanomas. Similar activities were generally observed for DDP and CHIP, whereas CBDCA exhibited a lower, although not significantly different cytotoxicity on breast and ovarian cancers. The relative activities of Platinum analogues were analyzed on 239 two-way drug sensitivity comparisons. The overall agreement rates ranged from 80.2 to 83.9% for the different comparisons. High coresistance, from 61.1 to 93.8%, was observed for all the comparisons, regardless of the tumor type. Cosensitivity rates were poor for breast and ovarian cancers, from 0 to 37.5%, whereas for melanomas an association in sensitivity was observed in 80% of the cases.  相似文献   
42.
A longitudinal study was performed on Jewish children with moderately-severe to profound hearing impairment born in Jerusalem during a period of 15 years (1967-1982), and the data on consanguineous matings among their parents were analyzed. These data were estimated in relation to the records obtained in an earlier survey performed on Jewish deaf children during the years 1955-1964. The rate of consanguinity among the parents of hearing-impaired children was much lower in the present survey than in the earlier one in both the Ashkenazi (Central and Eastern European origin) and the non-Ashkenazi (Asian-African origin) group. It is assumed that there is a better understanding of the genetic risk in consanguineous unions, especially when a disability such as hereditary deafness is involved.  相似文献   
43.
In the present study 57 consecutive patients with a first episode of venographically proven deep vein thrombosis were investigated to evaluate the release of tissue-type plasminogen activator (t-PA) and of urokinase-type plasminogen activator (u-PA) in response to DDAVP stimulation as well as the resting plasminogen activator inhibitor (PAI) concentration, comparing this to the results obtained in 66 similar patients with a clinical suspicion of thrombosis but with a normal venogram. All assays were performed without knowledge of the patient's status. Four patients in the deep vein thrombosis-group (7%) had an absent u-PA antigen response upon DDAVP infusion, while a normal response was observed in all control subjects. Patients and controls showed similar increases in t-PA antigen level upon DDAVP. High resting PAI antigen levels were encountered in 5 patients in the deep vein thrombosis-group (9%) and in 6 subjects in the control group (9%). The results from this controlled study indicate that a defective release of u-PA may occur in patients with deep vein thrombosis and may have pathogenetic significance. Furthermore it is concluded that elevation of PAI levels cannot be considered as a specific risk factor for venous thrombosis.  相似文献   
44.
Forty-four patients with documented meningeal carcinomatosis (small-cell lung carcinoma [SCLC], 29%; breast carcinoma, 25%) were treated in a prospective randomized trial with intrathecal methotrexate (MTX) 15 mg or MTX plus cytosine arabinoside (Ara-C) 50 mg/m2. Most patients received intrathecal hydrocortisone (HC) each treatment to minimize arachnoiditis. Overall response was 55%. Seven patients achieved complete response. Response to MTX was superior to combined MTX/Ara-C, but not significantly so (61% v 45%; P greater than .10). Response was more frequent if drugs were administered via Ommaya reservoir than by lumbar puncture (65% v 48%; P greater than .10). Concurrent radiotherapy to the CNS was associated with significantly better response (73% v 35%; P less than .05). Small-cell lung carcinoma patients showed the best response (69%). Overall median survival for the whole group was 8 weeks, but responders fared better than nonresponders (median survival, 18 v 7 weeks; P less than .05). Nausea and vomiting were the most common toxicities encountered (45%), but rarely proved limiting. An unusual, previously undocumented reaction to intrathecal HC was noted. MTX is moderately effective in nonleukemic meningeal carcinomatosis, but the addition of Ara-C does not appear to improve results. Pretreatment factors did not predict outcome in this trial.  相似文献   
45.
Clival chordoma presenting with acute brain stem hemorrhage.   总被引:1,自引:0,他引:1  
The authors present a case of a 29-year-old man who developed rapidly progressive cranial nerve palsies and a right hemiparesis secondary to a pontine hemorrhage. The rare but correct diagnosis of a clival chordoma which had invaded the brain stem and subsequently hemorrhaged was based on computed tomography and magnetic resonance imaging. The diagnosis was confirmed at surgery when the patient underwent a successful operative decompression of tumor and clot from the pons via a sub-occipital craniotomy. This represents the first case of a clival chordoma to hemorrhage into the brain stem, which was diagnosed preoperatively and the patient survived.  相似文献   
46.
Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin.  相似文献   
47.
The aim of this work is to correlate the net kidney uptake of99mTc-aprotinin (TcA) in 103 subjects with separate effective renal plasma flow (ERPF) and some blood chemistry parameters at 90, 180, and 360 min postinjection both in the normal and diseased kidney. Correlations found with separate ERPFs are highly significant at any time (P < 0.001). However, although the slope of the regression line is steeper at 180 min,r tends to deteriorate slightly with time postinjection and a higher intercept on they axis: this pattern is more pronounced if diseased kidneys are considered separately. The following are probably related to the renal handling of TcA: (1) Early scans better reflect blood flow to the kidney, while later scans are more related to the metabolism/excretion tubular mechanisms; (2) correlations found with urea, creatinine, urea clearance, and creatinine clearance are highly significant at any time; (3) in 20 additional patients with diseased kidneys, renal uptake measurements done 360 min postinjection first with TcA and then with DMSA showed better correlations with ERPF employing TcA. Our results indicate that TcA is a feasible indicator of split renal function even at 90 min postinjection when a scan is easily carried out on an outpatient basis.This paper was in part presented at the European Nuclear Medicine Congress, August 14–17, 1984, Helsinki, Finland  相似文献   
48.
A study was carried out to analyse trends in cancer mortality sex differentials. This study compared age-standardized sex ratio values for mortality from 18 cancers (or groups of cancers), and total cancer mortality over the period 1950-1989 in 24 European countries, for 4 age groups (all ages, 20-44 years, 45-64 years, and 65 years and over). For lung cancer and other tobacco-related neoplasms, appreciable rises in sex ratio values were observed until the late 1970s, particularly in Southern and Eastern Europe, before levelling off in recent years, particularly among the younger age groups. In the late 1980s, the range of variation in overall age-standardized sex ratios for lung cancer was between 2 and 3 in the United Kingdom and in Nordic countries, and around or over 10 in Southern Europe. In young adults, the decline in sex ratio values observed in Denmark and Sweden (unity), and in other Nordic countries and in the United Kingdom (around or below 2) reflects a levelling of lung cancer in young males and an increase in young females. This clearly indicates that young women are a priority target group for smoking control interventions in Europe. Appreciable cohort effects were also observed for stomach cancer: rises in sex ratio values were greater in, or restricted to, middle- and older age groups, whereas in the young there was some tendency towards a levelling in sex differentials. The overall sex ratio values for stomach cancer were around 2 in most areas of Europe in the late 1980s. For intestinal cancer, sex ratio values showed some tendency to rise, reaching a level of 1.3-1.7 in the late 1980s; steady rises were also registered in sex ratio values for melanoma (skin cancer), reaching 1.5-1.8 in the late 1980s in most countries. These upward trends which were minor or inconsistent at younger ages in several countries became progressively stronger with advancing age. Sex ratio values were below unity for cancers of the gallbladder and the thyroid. Sex ratio values tended to rise also for leukaemia (from 1.2-1.5 to 1.5-1.7), but showed no noticeable trend for lymphomas or myeloma. The overall sex ratio values for total cancer mortality in the 1950s were between 1.2 and 1.4 in most European countries. Thereafter, they rose appreciably in several countries, reaching 1.9 in Czechoslovakia, Italy and Poland, and 2.3 in France.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
49.
Total extrusion of the talus without recovery of the bone is a very unusual injury. The authors present a case of a 25-year-old man who sustained an open total enucleation of the talus in a motorcycle accident. The talus was not recovered at the scene of the accident. An immediate tibiocalcaneal stabilization was performed by using an external fixator. In the postoperative period, a polymicrobic infection was observed and treated with parenteral antibiotics. Nine months after injury, the patient developed an infection of both the empty space and the distal third of the tibia. A wound debridement with tibial sequestrectomy and insertion of gentamicin-impregnated polymethylmethacrylate beads was performed. Three months later, after multiple negative bacteriologic examinations, a tibiocalcaneal arthrodesis with staples and autogenous bone graft was performed. Because of a pseudoarthrosis, the patient underwent a revision of the arthrodesis by retrograde tibiocalcaneal nailing, achieving clinical and radiographic success. The definitive treatment of total enucleation of the talus is still controversial because of its rarity and the high rate of complications, such as avascular necrosis, osteomyelitis, and ankle stiffness. In this case, without recovery of the talus, retrograde nailing afforded good stability by bypassing the bone defects.  相似文献   
50.
Summary:  Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits.  相似文献   
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