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41.
Our species, Homo sapiens, is highly autapomorphic (uniquely derived) among hominids in the structure of its skull and postcranial skeleton. It is also sharply distinguished from other organisms by its unique symbolic mode of cognition. The fossil and archaeological records combine to show fairly clearly that our physical and cognitive attributes both first appeared in Africa, but at different times. Essentially modern bony conformation was established in that continent by the 200–150 Ka range (a dating in good agreement with dates for the origin of H. sapiens derived from modern molecular diversity). The event concerned was apparently short-term because it is essentially unanticipated in the fossil record. In contrast, the first convincing stirrings of symbolic behavior are not currently detectable until (possibly well) after 100 Ka. The radical reorganization of gene expression that underwrote the distinctive physical appearance of H. sapiens was probably also responsible for the neural substrate that permits symbolic cognition. This exaptively acquired potential lay unexploited until it was “discovered” via a cultural stimulus, plausibly the invention of language. Modern humans appear to have definitively exited Africa to populate the rest of the globe only after both their physical and cognitive peculiarities had been acquired within that continent.  相似文献   
42.
BACKGROUND: Adjuvant systemic therapy prolongs disease-free and overallsurvival in both pre- and postmenopausal patients. Availabledata shown benefit from multi-agent chemotherapy, prolongedtamoxifen treatment, and ovarian ablation, and that the combinationof chemo- and endocrine therapy might be advantageous. In 1978the International (Ludwig) Breast Cancer Study Group (IBCSG)initiated four complementary randomized controlled clinicaltrials to evaluate the roles of chemo-endocrine combinationsor endocrine therapy alone in specific populations defined byrisk (for pre- and perimenopausal patients) or by age (for postmenopausalpatients). The results at 10 and 13 years' median follow-upfor these trials are summarized in this report and are comparedto those of the Overview meta-anal-ysis with regard to chemo-endocrineor endocrine therapy combinations. Furthermore, types of firstrelapses by sites and second malignant diseases are reported. PATIENTS AND METHODS: 1601 evaluable patients with node positive disease were includedinto the studies I–IV. In Trial I (491 premenopausal patientswith 1–3 positive axillary nodes) we studied the additionof low-dose continuous prednisone (p) to a cyclophosphamide-methotrexate-fluorouracil(CMF) combination. In Trial n 327 premenopausal patients withfour or more positive axillary nodes were randomized to oneyear CMFp or to a surgical oophorectomy followed by CMFp. InTrial III (463 postmenopausal patients 65 years old or younger),combined chemoendocrine therapy (one year of CMFp plus tamoxifen(T)) was compared to endocrine therapy (1 year of p + T) orto surgery alone. In Trial IV 320 postmenopausal patients 66to 80 years old were treated either by surgery alone or by surgeryfollowed by 1 year prednisone and tamoxifen. RESULTS: In Trial I the addition of prednisone allowed a higher doseof cytotoxics to be administered compared with CMF alone. Despitethis increased dose intensity, 13-year disease-free survival(DFS) and overall survival (OS) were similar for the two treatmentgroups (49% vs. 52% DFS, 59% vs. 65% OS for CMFp vs. CMF). InTrial II the addition of surgical oophorectomy to CMFp yieldedan improved outcome which approached statistical significancefor the subset of 107 patients known to have estrogen receptor-positivetumors (DFS, 23% vs. 15%, p  相似文献   
43.
Forty-three patients with recurrent and metastatic squamous cell carcinoma of the cervix received a program of sequential combination chemotherapy incorporating induction with cisplatin, vinblastine, and bleomycin (PVB) and subsequent consolidation with 5-fluorouracil, doxorubicin, cyclophosphamide, and vincristine (FACV). The overall response rate was 62% and 10 patients (23%) achieved complete remission. Response status was improved in 11 patients at the completion of FACV after initial PVB therapy, including 9 complete remissions. The median survival for all patients in the study was 38 weeks and 50 weeks for the responding patients. Myelosuppression was the principal toxicity encountered and 10 episodes of neutropenic sepsis occurred, including one septic death. However, the only cumulative toxicity was peripheral neuropathy, although this was only moderate to severe in 2 patients. These results are encouraging, but will require confirmation in randomized comparison to cisplatin, presently accepted as standard single-agent therapy.  相似文献   
44.
Background: Follow-up tests for patients after diagnosis andprimary treatment of breast cancer are routinely performed.However, the usefulness of these follow-up parameters remainsunclear. We determined the yield of a variety of blood testsused to detect the presence of overt metastatic disease Methods: 4105 patients enrolled in International (Ludwig) BreastCancer Study Group (IBCSG) randomized clinical trials from 1978to 1985 were analyzed for abnormal or equivocal findings insix routine blood tests obtained every 3 months for the firsttwo years, every six months for years 3–5 and yearly thereafter.The relationship of test results to the occurrence of overtmetastatic disease was evaluated. The relapses were categorizedas follows in order to estimate the yield of the different testsfor relevant sites of metastases: any breast cancer relapse,bone ± other; liver ± other Results: Alkaline phosphatase alone was abnormal in a high proportionof patients with either bone metastases, liver metastases, orboth. SGOT and gamma-GT were also sensitive for patients withliver metastases. Bilirubin, serum calcium, and serum creatininewere relatively insensitive indicators of relapse. Abnormaltest results were reported sometime during a patient's disease-freeperiod for 3% to 6% of patients, depending on the test Conclusions: Alkaline phosphatase was the most effective bloodtest to distinguish patients with relapse from those withoutrelapse. It is inexpensive and its yield is relatively highfor predicting liver and bone metastases. The routine use ofthe other tests analyzed to detect metastases was not justified breast cancer, follow-up, evaluation, routine tests  相似文献   
45.
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There have been extensive observations that RNA containing repetitive elements accumulates in transformed cells and tumor tissues. In the present study, we first obtained result consistent with previous observations by in situ hybridization.  相似文献   
48.
OBJECT: The goals of this study were to define the incidence of seizures in children with low-grade tumors, study seizure outcome after lesionectomy in these children, and identify risk factors for poor seizure outcome, METHODS: The authors performed a retrospective chart review of children who harbored low-grade brain tumors, experienced seizures, and were treated in a single institution, Statistical analyses included step-wise as well as single-variable binary logistic regression analyses.  相似文献   
49.
PURPOSE: Informed decision making now is considered the underpinning of ethical medical practice. We aimed to determine the extent to which patients with incurable cancer are adequately informed of their prognosis and treatment options and encouraged to participate in treatment decisions. PATIENTS AND METHODS: One hundred eighteen cancer patients with incurable disease presenting for an initial consultation with one of nine oncologists at two Sydney tertiary referral hospitals participated in the study. Consultations were recorded on audiotape to permit a content analysis of doctor-patient interactions. We devised a coding system to assess disclosure of information and to evaluate doctor encouragement of patient participation in treatment decision making. Patient recall, satisfaction, anxiety, and perceptions of the decision-making process were assessed to determine the effects of informed decision making on patient outcomes. RESULTS: Most patients were informed about the aim of anticancer treatment (84.7%), that their disease was incurable (74.6%), and about life expectancy (57.6%). An alternative to anticancer treatments was presented to 44.1%, 36.4% were informed about how anticancer treatment would affect quality of life, and 29.7% were offered a management choice. Oncologists checked patient understanding in only 10.2% of consultations. Although greater information disclosure did not seem to elevate anxiety levels, greater patient participation in the decision-making process was associated with increased anxiety levels (P =.0005), which persisted over a 2-week time span. CONCLUSION: Most patients were well informed, but important gaps remain, especially concerning information about prognosis and alternatives to anticancer treatment. These gaps invite the question concerning whether patients are led toward anticancer treatment.  相似文献   
50.
BACKGROUND: To evaluate the impact of an educational booklet on women's knowledge of and willingness to participate in a randomized clinical trial of treatment for breast cancer. MATERIALS AND METHODS: Women undergoing surgery for newly diagnosed early stage breast cancer were randomized to receive, or not, an information booklet explaining the need for and manner in which randomized trials are conducted. RESULTS: Eighty-three women with newly diagnosed early stage breast cancer completed a questionnaire assessing attitudes to random clinical trials (RCTs) and were randomized to receive usual information treatment options provided from their oncologist, or the educational booklet in addition to usual information from their oncologist (42 usual information, 41 booklet). Fewer women who received the clinical trials booklet (40% versus 47%) would consider participating in the hypothetical clinical trial (P = 0.6). Mean knowledge scores increased for both groups; moreover, women who did not receive the booklet showed similar improvements to women who received the booklet [mean difference 0.09, 95% confidence interval (CI) -0.66 to 0.83]. In a multivariate analysis women who would consider participating in the clinical trial were more anxious [odds ratio (OR) 5.9, P = 0.02] had involved lymph nodes (OR 5.8, P = 0.02) and were less influenced by negative aspects of clinical trials (OR 7.7, P = 0.0001). After adjustment for these variables women who received the educational booklet were significantly less likely to consider trial participation (OR 0.22, P = 0.05). CONCLUSIONS: Educating women about clinical trials in this manner appears ineffective in improving recruitment to RCTs. Women appear to be more influenced by their perception of risk than understanding. This finding has ethical implications for communication of information about RCTs.  相似文献   
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