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21.
Two spontaneous prolactinomas, removed from 28-mo-old female Wistar/Furth rats, were grafted by serial passages under the kidney capsule and the skin in 117 females of the same consanguineous strain. The hosts, aged between 2 and 10 mo, were free of estrogen treatment. These transplantable tumors, named SMtTW1 and SMtTW2, were studied until the fifth serial passage. The percentage of success was 100% under the kidney capsule and 20% under the skin. From the radioimmunoassays of prolactin (PRL), growth hormone, and adrenocorticotropic hormone and the immunocytochemical results, the tumors secrete PRL only. The PRL tumoral secretion was detected after 3 to 5 mo of graft; at 8 mo, mean plasma PRL values reached 5150 ng/ml (normal value, 15.2 ng/ml). Plasma growth hormone and adrenocorticotropic hormone values remained normal. Like the primary tumors, the grafted tumors were benign, grew slowly, and were sparsely granulated well-differentiated prolactinomas with exocytosis. They remained identical during the first serial passages. The secretion and the growth of SMtTW2 were inhibited by bromocriptine. In the light of our knowledge of the human prolactinoma, the spontaneous transplantable prolactinoma of the rat may be considered to be an animal model closer to the human pathology than the estrogen-induced "tumors" and the induced transplantable tumors. It is easier to use than the spontaneous prolactinoma of the rat.  相似文献   
22.
Breast cancer is the most common malignancy in women, accounting for about 18% of female cancers, and over half a million new cases are diagnosed worldwide each year. Its incidence increases with age and is currently rising. Although the increased availability of screening programs has allowed earlier detection and treatment of primary breast cancers, many patients relapse with metastases after apparently successful treatment of their primary tumor and over 15,000 women in the UK and about 50,000 in the USA die from advanced disease each year. The natural course of breast cancer is very variable even after the development of metastases, and depends on a variety of tumor characteristics and prognostic factors. This is reflected in the large number of treatments currently employed. However, despite this wide choice and considerable research over the years, treatment of metastatic breast cancer (MBC) prolongs average survival times only slightly. Current therapy is aimed at achieving a balance between producing maximal tumor shrinkage to produce the most effective possible palliation of symptoms, and minimizing adverse effects. Anticancer chemotherapy is the preferred option in patients who do not respond to hormones, those with hormone-independent tumors, those with aggressive breast cancer subtypes. A variety of anticancer chemotherapy regimens, using both single and combined agents, have been shown to be effective in achieving tumor regression in MBC. Anthracyclines (doxorubicin, epirubicin) are the most active of the established monotherapies, typically producing response rates of 50-60% during initial (first-line) treatment for metastatic disease, but being effective in fewer than 25% of patients requiring second-line therapy. The drawbacks of anthracyclines include dose-limiting cumulative cardiotoxicity and the development of resistant tumor clones after the use of anthracyclines for adjuvant or first-line therapy, especially if subsequent courses are required within a year. The success of these established chemotherapeutic agents depends greatly on the number and location of metastatic sites. Lymph node and soft tissue secondaries tend to respond well, while visceral metastases (especially in the liver) carry a particularly poor prognosis despite treatment. The outlook for patients with metastases involving more than two organ systems is also bleak. Although some patients can live for years with metastatic disease, the average survival time in patients with MBC is 18-24 months, while in those with liver metastases, life expectancy averages only 6 months. High-dose anticancer chemotherapy with granulocyte-colony stimulating factor (G-CSF) or autologous bone marrow transplantation has allowed the dose intensity of anthracyclines to be increased, and has improved the response rate to about 70% in selected patients with MBC. However, this approach has not been proven to improve survival, involves the risk of greater toxicity and drug-related mortality, and patients with reduced clearance of anthracyclines due to hepatic dysfunction from liver metastases may not be suitable candidates. A number of new anticancer agents have also recently been introduced in an attempt to improve on the performance and avoid the tolerability problems associated with anthracyclines. Among these, antitubulin agents (taxoids and vinorelbine) have shown highly promising activity in MBC. This paper reviews the preclinical, phase I and phase II data for one taxoid, docetaxel. Docetaxel (Taxotere) belongs to the taxoid class of cytotoxic agents, the development of which began more than 20 years ago. In 1971, paclitaxel (Taxol) was identified as the active compound of the crude extract of the bark of the Pacific Yew tree Taxus brevifolia. However, at that time the development of paclitaxel was hampered because of the limited source of the drug and difficulties with isolation, extraction and formulation. The second active taxoid, docetaxel, was isolated by Potier et al. in 1986. Docetaxel is prepared from a non-cytotoxic precursor, extracted from the needles of the European Yew tree Taxus baccata, that is condensed with a chemically-synthesized side-chain. As the docetaxel precursor is freely available because of the regenerating capacity of the needles the development of docetaxel has thus been rapid.  相似文献   
23.
Summary We evaluated the efficacy and tolerability of lobaplatin, a new platinum compound, given at the dose of 50 mg/m2 by i.v. bolus every 4 weeks, in 49 patients with advanced and/or metastatic squamous cell carcinoma of the head and neck (SCCHN). One complete and 2 partial responses were observed in 43 eligible patients for an overall response rate of 7% (95% confidence interval: 1–19%). The duration of responses was 11, 16 and 32 weeks. Toxicities of WHO grade 3 were hematologic: thrombocytopenia in 26%, granulocytopenia in 12% and anemia in 12% of patients. There was no therapy-related death. Nausea/vomiting, diarrhoea and paresthesia were mild and rare. In conclusion, lobaplatin was well tolerated, but its efficacy in advanced SCCHN at the presented dose and schedule, was marginal.  相似文献   
24.
We report a case of staghorn nephrolithiasis that evolved into xanthogranulomatous pyelonephritis with perinephric abscess, nephrobronchial fistula, and lung abscess. The patient was an intravenous drug abuser who tested positive for human immunodeficiency virus, without evidence of acquired immunodeficiency syndrome. He presented with a 2-month history of untreated repeated episodes of left flank pain and hyperpyrexia. Treatment involved left nephrectomy, debridement of abscess, tube drainage, and intravenous antibiotics. The patient illustrates the need to consider untreated nephrolitiasis as a predisposing factor for pulmonary complications.  相似文献   
25.
26.

Purpose

Treatment of cystoceles and stress urinary incontinence continues to evolve. We evaluated the efficacy of a new vaginal wall sling procedure for cystocele repair and treatment of stress urinary incontinence.

Materials and Methods

We present our experience with the vaginal wall sling procedure in 36 patients (mean age 67.4 years) with cystocele. Of the patients 16 had undergone a prior pelvic operation. With our technique a vaginal wall tube was created with the base in the bladder neck and fixation to the periurethral tissues or suspension to the suprapubic area.

Results

Success rates were 95 and 82 percent for cystocele and stress incontinence repair, respectively. Mean followup was 17 months. Morbidity was minimal and mean hospitalization was less than 5 days.

Conclusions

This original, simple, noninvasive treatment is applicable for all cystoceles regardless of patient age or sexual activity, and has shown encouraging results. Based on our experience we recommend this procedure for repair of cystoceles and stress urinary incontinence.  相似文献   
27.
Summary To characterize the in situ cellular immune response in localized cutaneous leishmaniasis (LCL), the authors studied frozen skin biopsies from 50 patients with LCL due toLeishmania braziliensis guyanensis. A panel of 31 monoclonal antibodies was used, which defined the number and distribution of inflammatory cell subsets. Skin inflammatory infiltrates were composed of T cells (with a local CD4/CD8 ratio of 1.05±0.7 vs 1.48±0.3 in peripheral blood), macrophages and a smaller number of B cells, natural killer cells and granulocytes. Most of the T cells expressed activation markers (interleukin-2 and transferrin receptors, HLA-DR+) and an increase in T-cell-receptor expression was noted. Analysis of the CD4+ subpopulations with newly available reagents showed that helper T cells (CD4+CD45RO+) exceeded the suppressor/inducer subset (CD4+CD45RA+) by 1.41. There were no differences between local immune variables from patients with primary infection (45 patients) and those with recurrence (5). In 7 patients, biopsies were analysed before and 1 month after specific treatment, and did not show significant differences except for a small increase of dermal CD1a+ (Langerhans) cells/mm2. The observed pattern of cellular skin infiltration suggests an immune-mediated tissue injury including T-cell-mediated cytotoxicity and delayed hypersensitivity reactions in addition to direct parasitic action.  相似文献   
28.
29.
OBJECTIVES: Reduction of the weight in obese patients is a pre-condition for the aesthetic improvement of obesity or its after effects by plastic surgery. The aim of this study was to evaluate the effectiveness and advantages of gastric banding, using a ring positioned under laparoscopic guidance. PATIENTS AND METHODS: Thirty-nine patients with morbid obesity were operated on. For the first nine patients, gastric restriction was obtained by Mason's traditional technique. In the remaining thirty, a Kuzmak ring was positioned a few centimeters under the cardia, under laparoscopic guidance. The study concerned the evolution of weight, associated pathologies, and complications. RESULTS: Three months after surgery, all patients had lost weight (mean loss: 15 kg). At six months, a mean weight loss of 26 kg was observed. At one year, the mean weight loss was 35 kg. Two patients experienced postprandial vomiting that justified widening of the ring; one ring was poorly tolerated and was removed 10 days after surgery. CONCLUSION: This new surgical technique is effective for reducing the weight of obese patients. The laparoscopic approach to the stomach reduces parietal complications and enables subsequent abdominal plastic surgery to be performed.  相似文献   
30.
Schools have been a point of attention during the pandemic, and their closure one of the mitigating measures taken. A better understanding of the dynamics of the transmission of SARS-CoV-2 in elementary education is essential to advise decisionmakers. We conducted an uncontrolled non-interventional prospective study in Belgian French-speaking schools to describe the role of attending asymptomatic children and school staff in the spread of COVID-19 and to estimate the transmission to others. Each participant from selected schools was tested for SARS-CoV-2 using a polymerase chain reaction (PCR) analysis on saliva sample, on a weekly basis, during six consecutive visits. In accordance with recommendations in force at the time, symptomatic individuals were excluded from school, but per the study protocol, being that participants were blinded to PCR results, asymptomatic participants were maintained at school. Among 11 selected schools, 932 pupils and 242 school staff were included between January and May 2021. Overall, 6449 saliva samples were collected, of which 44 came back positive. Most positive samples came from isolated cases. We observed that asymptomatic positive children remaining at school did not lead to increasing numbers of cases or clusters. However, we conducted our study during a period of low prevalence in Belgium. It would be interesting to conduct the same analysis during a high prevalence period.  相似文献   
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