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1.
We used the species specificity and repetitious nature of subtelomeric kinetoplastida sequences to generate a duplex PCR assay for the simultaneous detection of Trypanosoma cruzi and Trypanosoma rangeli in experimentally and naturally infected triatomine (Reduviid) bugs and in infected human subjects. The assay was species specific and was capable of detecting 1/20th of T. cruzi and 1/4th of T. rangeli cell equivalents without complementary hybridization. In addition, the PCR-based assay was robust enough for direct application to difficult biological samples such as Reduviid feces or guts and was capable of recognizing all T. cruzi and T. rangeli strains and lineages. Because the assay primers amplify entirely different target sequences, no reaction interference was observed, facilitating future adaptation of this assay to an automated format.  相似文献   
2.
We have followed the appearance of two microtubule proteins, tubulin and microtubule-associated protein 2, in rat hippocampal neurons differentiating in cell culture. Double-label immunofluorescence staining showed that from day 1 in vitro onward tubulin appeared as filaments but that microtubule-associated protein 2 remained distributed throughout the cytoplasm. This difference persisted throughout development and was also detectable in cells that had reached morphological maturity. When cells were treated with the microtubule-depolymerizing agent nocodazole, the depolymerized tubulin became spread throughout the cytoplasm so that its distribution was then identical to microtubule associated protein 2. At the same time, multiple side branches began to emerge along the dendrites. When cells which had been exposed to nocodazole were allowed to recover before staining, the tubulin was again present as filaments but the microtubule-associated protein 2 remained distributed throughout the dendritic cytoplasm. Under these conditions the previously extended proximal side branches were resorbed into the main process. These results suggest that cellular microtubule-associated protein 2 is not necessarily exclusively associated with microtubules. Neuronal dendrites in particular appear to contain this protein at levels in excess of the capacity of microtubular microtubule-associated protein 2 binding sites. In view of the known effectiveness of microtubule-associated protein 2 as a promoter of tubulin polymerization, its abundance in dendrites suggests that it acts to ensure total polymerization of dendritic microtubules. In this way it would contribute both to the support of the growing process and the suppression of adventitious sidebranching.  相似文献   
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The growth properties of single-tumor-cell suspensions prepared by enzymatic digestion of solid tumors from Morris hepatomas 7777, 5123tc, and 3924a and the presence of tumor-specific transplantation antigen for tumor lines 7777 and 3924a were described. Two of the tumor cell lines (7777 and 3924a) showed consistent i.m. tumor growth following the inoculation of 1 x 10(5) tumor cells, and a similar dose of 5123tc tumor cells resulted in inconsistent tumor growth. Two of the tumor lines (5123tc and 7777) were associated with rapid appearance of lung metastases, whereas with line 3924a metastatic lung lesions rarely developed despite its rapid i.m. tumor growth rate. Tumor resistance to rechallenge with a threshold inoculum of tumor cells was present in approximately 15 to 50% of the animals following amputation of an existing tumor mass. Resistance to a challenge tumor cell inoculum could also be accomplished by immunization with irradiated tumor cells. Tumor-specific resistance was demonstrated to tumor line 3924a in that "immune" animals were able to resist a challenge with 3924a tumor cells but did not resist a challenge with tumor line 9098.  相似文献   
5.
Background: The presence in bone marrow of cells which react with monoclonal antibodies against tumor-associated antigens has been proposed over the last few years as a new prognostic factor in breast cancer patients. Patients and methods: Bone marrow aspirates were obtained from 109 stage I and II breast cancer patients during or 2–4 weeks after primary surgery. The samples were processed for leukocyte separation on a Ficoll-Hypaque gradient and then used to prepare cytospin slides for immunocytochemical analysis. The slides were stained with a pool of monoclonal antibodies (MoAbs) which recognize tumor associated antigens, using the alkaline phosphatase anti-alkaline phosphatase method. The median follow-up was 36 months (range 15–62); 22 patients relapsed and 7 died. Results: Thirty-four of the 109 patients (31.1%) had MoAb positive bone marrow cells. The bone marrow was positive in 28/74 (37.9%) patients who had the aspirate taken during surgery and in 6/35 (17.1%) who had it taken after surgery (p = 0.055). No association was found between bone marrow positivity and tumour size, nodal status, menopausal status, estrogen receptor positivity or the proliferative index. No association was found between bone marrow and prognosis: the log-rank test was 0.291 (p > 0.5) for OS and 0.023 for DFS; the hazard ratio (positive vs negative) was 1.51 for OS (95% CI: 0.33–6.86) and 0.93 for DFS (95% CI: 0.35–2.45). Conclusions: In our series, bone marrow positivity did not correlate with prognostic parameters or prognosis. Of interest is the relative excess of positivity when the bone marrow was obtained during surgery.  相似文献   
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Lateral left ventricular wall rupture (LVWR) is a rare complication following acute myocardial infarction (AMI) less than 1%. After cardiogenic shock, LVWR constitutes the most common cause of in‐hospital death in AMI patients. Around 40% of all LVWR occurred during the first 24 hours and 85% within the first week. In the present case, 76 hours following the intervention, LVWR was observed likely due to a small infarction at the lateral left ventricular wall possibly due to the marginal lesion. Our patient refused surgery and was followed clinically. Eighteen months later, real time three‐dimensional echocardiography showed a pseudoaneurysm.  相似文献   
9.

Context

There is limited literature regarding outpatient palliative care and factors associated with unscheduled clinic visits.

Objectives

To compare characteristics of patients with unscheduled vs. scheduled outpatient palliative care clinic visits.

Methods

Medical records of 183 unscheduled cancer new outpatients and 104 unscheduled follow-up (FU) patients were compared with random samples of 361 and 314 scheduled new patients and FU patients, respectively. We gathered data on demographics, symptoms, daily opioid usage, and performance status.

Results

Compared with scheduled new patients, unscheduled new patients had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P = 0.002), nausea (P = 0.016), depression (P = 0.003), anxiety (P = 0.038), drowsiness (P = 0.002), sleep (P < 0.001), and overall feeling of well-being (P = 0.001); had a higher morphine equivalent daily dose of opioids (median of 45 mg for unscheduled vs. 30 mg for scheduled; P < 0.001); and were more likely to be from outside the greater Houston area (P < 0.001). Most unscheduled and scheduled new and FU visits were for uncontrolled physical symptoms. Unscheduled FU patients, compared with scheduled FU patients, had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P < 0.001), depression (P = 0.002), anxiety (P = 0.004), drowsiness (P = 0.010), appetite (P = 0.023), sleep (P = 0.022), overall feeling of well-being (P < 0.001), and higher morphine equivalent daily dose of opioid (median of 58 mg for unscheduled FU visits vs. 40 mg for scheduled FU visits; P = 0.054).

Conclusion

Unscheduled new FU patients have higher levels of physical and psychosocial distress and higher opioid intake. Outpatient palliative care centers should consider providing opportunities for walk-in visits for timely management and close monitoring of such patients.  相似文献   
10.
Gastrointestinal carcinoid tumors arise from cells of the diffuse neuroendocrine system localized in the digestive trace and represent more than 70% of all carcinoid tumors in humans. The present article reviews the following topics: 1) The biological profile of these tumors (histopathology, cytokine markers, metabolic alterations, storage of neuroamines and hormonal proteins, cytodynamic behavior, and biological behavior according to embryological origin). 2) The etiological circumstances (exceptional hereditary factors, association of gastric carcinoid tumors with autoimmune gastritis, little-known exogenous factors). 3) Pathogenic aspects (persistent mitogenesis of endocrine cells associated with hypergastrinemia, inactivation of some putative tumor suppressor genes, the doubtful participation of oncogenes, autocrine action of some cellular growth-stimulating proteins). 4) The repercussions of certain physiopathological events (peritumoral desmoplastic reaction causing the "mass effect" on the digestive tube, the "kidnapping" of dietary tryptophan by tumoral cells toward an abnormal metabolic pathway; the easy metastatic dissemination coexisting with low tumoral aggressivity, and the release into the bloodstream of stored secretory products leading to "carcinoid syndrome" and some endocrine hyperfunction syndromes. Finally, it should be remembered that gastrointestinal carcinoid tumors represent only a proportion of the neoplasms classified as neuroendocrine tumors.  相似文献   
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