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61.
We have adapted the simple and sensitive McAb-antigen spot test (AST) for evaluating the efficacy of anti-Leishmania chemotherapy. Serum samples from 37 kala-azar patients were tested by McAb-AST, and all showed definite positive reactions before treatment. After a course of antimony treatment, 20 turned negative, coupled with the disappearance of clinical symptoms; another 12 cases responded with weak positivity accompanied by an improvement of clinical manifestations; and the remaining 5 antimony-resistant patients showed strong positive reactions, with their conditions gradually worsening. Furthermore, all 6 cases in which the diagnosis was missed by the bone marrow smear method turned McAb-AST negative after chemotherapy. These results suggest that McAb-AST can be used to evaluate the efficacy of chemotherapy as well as to avoid missed diagnosis by the bone marrow smear method.  相似文献   
62.
The mitogenic, chemotactic, and synthetic responses of rat periodontal ligament (PDL) fibroblastic cells to epidermal growth factor (EGF), transforming growth factor-beta (TGF-beta), recombinant human platelet-derived growth factor (rhPDGF)-AB, rhPDGF-BB, natural (n) PDGF-AB, and insulin-like growth factor-I (IGF-I) were examined in vitro using PDL cells obtained from the coagulum of healing tooth sockets. PDGFs and IGF-I have potent and comparable mitogenic effects on PDL fibroblastic cells. The maximum mitogenic effect of PDGFs was observed at the concentration of 10 ng/ml, whereas that of IGF-I was seen at concentrations higher than 100 ng/ml. In contrast, EGF induced moderate, and TGF-beta inhibitory mitogenic responses. The combination of rhPDGF-AB with either EGF or TGF-beta demonstrated comparable mitogenic potency, equivalent to the level of PDGF alone regardless of the mitogenic effect of other growth factors. The combination of rhPDGF-AB and IGF-I, however, showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combinations of the growth factors tested. Similarly, PDL fibroblastic cells demonstrated strong chemotactic responses to both IGF-I and PDGFs. The maximum effect was observed by IGF-I at concentrations higher than 10 ng/ml, followed by rhPDGF-BB at 0.1 ng/ml, rhPDGF-AB and nPDGF at concentrations ranging from 0.1 to 1 ng/ml. TGF-beta revealed no, and EGF slightly increased, chemotactic effects. IGF-I slightly enhanced the synthesis of total protein, whereas other factors had no significant effect. However, both rhPDGF-AB and TGF-beta stimulated collagen synthesis. On the other hand, IGF-I showed no effect on collagen synthesis, while EGF suppressed collagen synthesis. These findings suggest that rhPDGF-BB and IGF-I stimulate proliferation and chemotaxis of PDL fibroblastic cells. In addition, the combination of these growth factors further increases the mitogenic effect. rhPDGF-AB also stimulates collagen synthesis by PDL fibroblastic cells. Thus, rhPDGF-BB and IGF-I may have important roles in promotion of PDL healing, and consequently, may be useful for clinical application in periodontal regenerative procedures.  相似文献   
63.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a patient's vascular access would permit routine monitoring during haemodialysis, and hence provide information of access graft deterioration sufficiently early to increase the success of minimally invasive remedial procedures. This paper reports the validation of such a method in animals. METHODS: A PTFE graft was implanted in sheep between the carotid artery and the jugular vein. While the sheep was under general anaesthesia and on an haemodialysis circuit, ultrasound velocity in its blood was perturbed by the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was measured by a transit-time blood flow meter. This flow was combined with the areas of perturbation generated by the injection before and after mixing in the access flow to estimate graft flow. The calculated graft flow was compared to flow measured directly by a transit-time probe on the same carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow measured by ultrasound velocity dilution agreed well with graft flow measured directly with a scatter of 76 ml/min about the regression line. CONCLUSION: Ultrasound velocity dilution provides a method for measuring flow in the graft accurate enough for clinical evaluation of patients on dialysis.   相似文献   
64.
OBJECTIVE: To describe the rationale, methodology, and general sample characteristics of the Canadian Psychiatric Association (CPA) practice profile survey, a national survey of psychiatrists and psychiatric practice. METHOD: Mail-in interviews were sent to all Canadian psychiatrists listed in their provincial registers and to all active CPA members (total = 3628). Respondents provided general information about their professional activities for one 24-hour day and detailed information for 1 randomly selected hour. Patient information--including sociodemographics, diagnostic profiles, functioning levels, risk of harm to self or others, and disposition--was elicited for 1 patient seen during the random hour as well as for the most seriously ill patient receiving clinical services that day. RESULTS: There was a 45.5% response rate. Questionnaires completed by nonpsychiatrists or with a large percentage of missing or incorrect data were eliminated (107 surveys), resulting in a final sample size of 1570. CPA members and those from Western Canada responded at a higher rate to the survey. The results suggest some cause for concern about future manpower shortages. Most psychiatrists practise eclectically, seeing patients across the life-span, and working in both community and institutional settings. The old and the young appear to be underserviced, compared with adults. CONCLUSIONS: This study represents an important step forward in evaluating the profile and activities of the profession.  相似文献   
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From May 1, 1985 to December 31, 1991, a total of 4,962,707 serum samples from 8 population groups in Taiwan were tested for anti-human immunodeficiency virus type 1 (anti-HIV-1). In total, 256 samples were seropositive; of these individuals, 43 developed acquired immunodeficiency syndrome (AIDS): 29 were homosexuals; 5 were hemophiliacs; 8 were heterosexuals and 1 was of unknown risk. Although the prevalence of HIV-1 infection and AIDS remains low compared with other countries, since 1988 the increase has been rapid. Before 1977 the majority were homosexuals and hemophiliacs; thereafter the risk groups diversified, with a trend away from homosexuals and hemophiliacs towards heterosexuals and intravenous drug abusers (IVDAs). A few patients have caused serious social problems for the public, health care workers and families. Active community efforts are needed to achieve future success in the control of HIV-1 infection and AIDS in Taiwan.  相似文献   
68.
The in vitro DNA amplification technique of polymerase chain reaction was used to evaluate the possible presence of human papillomavirus (HPV) in small cell carcinoma of the uterine cervix. None of the 12 cases examined contain detectable amounts of either HPV type 16, 18, 31, or 33 DNA. On the other hand, HPV types 16 and 18 DNA were found in 14 (93.3%) and 9 (60.0%) of 25 invasive cervical squamous carcinoma tissues. The results seem to suggest that these types of HPV are not present or are present in extremely small quantities in cervical small cell carcinoma. Such an absence of HPV DNA makes it unlikely that these types of HPV play any etiological role in the pathogenesis of cervical small cell carcinoma.  相似文献   
69.
The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with 14C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack CIS cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE2 was predominant among the PGs detected. Two radioactive bands corresponding to PGF and three unseparated standards of PGA2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2were detected in lesser amounts. Very small amounts of the lipoxygenase products 12-and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE2 synthesis (IC50) by SCC lines were .008- .080, .080–6.4 and 32–88 μM, respectively.  相似文献   
70.
本调查是对××冶炼厂227名接铅工人作了尿铅、尿中δ-ALA、尿粪卟啉及末梢血中碱粒红细胞的测定,同时与对照组进行了比较。结果表明:(1)接铅工人尿中δ-ALA检出均高出非接铅健康工人,且差别非常显著。(2)随着接铅工龄的增加,工人尿中δ-ALA的超标率也相应的增多。(3)接铅工人尿中δ-ALA的变化比CP要早,对铅的接触更敏感。(4)尿中δ-ALA与尿铅呈明显相关,而与碱粒红细胞相关不明显。  相似文献   
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