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排序方式: 共有190条查询结果,搜索用时 15 毫秒
181.
Medical impact of unedited preliminary radiology reports   总被引:3,自引:0,他引:3  
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182.
Bilateral breast carcinoma: mammographic and histologic correlation   总被引:2,自引:0,他引:2  
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183.
甲基黄酮醇胺对豚鼠气管平滑肌收缩及cAMP水平的影响   总被引:4,自引:0,他引:4  
观察了MFA对离体豚鼠气管张力,cAMP的影响及二者的关系。发现:MPA(0.03~0.6mmol·L-1)剂量依赖性抑制KCI,ACh及Hist所致的气管条收缩,同时伴有cAMP升高,两者间有良好的相关性(r值分别为0.753,0.9112和0.9567,P<0.001);MFA(0.03mmol·L-1)能够增强Ami和Iso的气管平滑肌舒张作用,后者同时伴有cAMP升高。提示:MFA对支气管平滑肌张力的抑制作用确与cAMP升高有关,MFA升高cAMP作用可能与其钙拮抗作用有关。  相似文献   
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186.
Bookchin  RM; Roth  EF Jr; Lew  VL 《Blood》1985,66(1):220-223
The belief is widely held, on the basis of indirect evidence, that a substantial, even brief elevation of red cell Ca content must result in a marked shortening of circulatory survival. To test this notion directly, we exposed rabbit red cells in vitro to the ionophore A23187 and Ca so as to produce sustained uniform cell Ca levels of 40 to 360 mumol/L cells for one to 60 minutes, and compared the survival of the Ca-loaded cells in vivo with that of ionophore-treated controls, simultaneously, in the same rabbits. Despite marked reductions in cell adenosine triphosphate and dehydration of the Ca-exposed cells prior to reinfusion, the majority of cells, all of which had experienced these high cytoplasmic Ca levels, showed normal or near-normal survival in the circulation.  相似文献   
187.
The recent focus on medical risk and financial cost has prompted a need for better guidelines for prescribing the transfusion of blood components. In 1987, to respond to the issues of quality transfusion practice and accurate evaluation, LDS Hospital (Salt Lake City, UT) began using a computerized, knowledge-based blood-ordering system. Each transfusion request was reviewed and flagged by the computer when it did not meet the criteria established by the medical staff. The study reviewed the use of red cells, platelets, and fresh-frozen plasma in 13,082 transfusion orders for 5847 consecutive patients from July 1, 1988, through June 30, 1989. The evaluation assessed, first, the adherence of physicians to computerized criteria and, second, their adherence to the quality of transfusion practice. A high percentage of the blood units ordered met the established criteria: 91.2 percent for the red cell transfusions, 72.9 percent for platelets, and 81.7 percent for fresh-frozen plasma. From the July 1, 1987, implementation date through June 1989, the mean hematocrit of persons being transfused dropped from 28.6 to 27.7 percent (0.29 = 0.28) (p less than 0.005) and the number of orders requiring review by the quality assurance department dropped from 100 to 14 percent; moreover, there was a true-exception rate of only 0.37 percent. The use of the computer system effected the implementation of the following measures: 1) identification of the indications and establishment of clear clinical and biologic parameters for every transfusion, and 2) measurement and improvement of institutional transfusion practice. These results demonstrated the efficacy of a computerized hospital information system in implementing continuous quality improvement for transfusion practice.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
188.
Velardi  A; Prchal  JT; Prasthofer  EF; Grossi  CE 《Blood》1985,65(1):149-155
Heterogeneity within lymphocyte subsets expressing T-helper (T4+/Leu3+) or T-suppressor (T8+/Leu2+) markers was analyzed in 38 patients with B cell chronic lymphocytic leukemia (B-CLL) and in 11 age-matched controls. Co-expression of NK-lineage markers (M1, Leu7) on Leu2+ or Leu3+ cells was investigated by two-color immunofluorescence, and the proportion of granular lymphocytes within each subset was determined by cytochemical staining for acid phosphatase. B-CLL patients and normal controls had similar absolute numbers of cells per microL with T- suppressor phenotype. However, the proportion of Leu2+ cells co- expressing the Leu7 antigen was higher in the B-CLL patients than in the control subjects (54 +/- 3% v 27 +/- 4%, P less than .0001). The absolute number per microL of cells with T-helper phenotype was somewhat decreased in B-CLL patients compared with normal subjects (649 +/- 104 v 799 +/- 33, P less than .02), with a consequent decrease of the helper/suppressor ratio. Furthermore, co-expression of the Leu7 and, more strikingly, of the M1 markers was increased significantly on Leu3+ cells from B-CLL patients compared with normal controls (11 +/- 2% v 2 +/- 0.7%, P less than .002 for Leu7 and 40 +/- 5% v 4 +/- 1%, P less than .00001 for M1). Cytochemical studies showed that a large proportion of Leu3+ cells from B-CLL patients were granular lymphocytes, as suggested by the co-expression of natural killer (NK) cell markers. The emergence of a population of Leu3+ granular lymphocytes with NK markers, which is barely detectable in normal subjects, may provide an explanation for the impairment of T cell functions repeatedly described in B-CLL.  相似文献   
189.

Background

Approximately 5-10% of breast cancers are hereditary. Among hereditary syndromes, Hereditary Breast and Ovarian Cancer Syndrome (HBOC) and Li-Fraumeni Syndrome (LFS) have received the most attention. HBOC is due to mutations in the BRCA1 and BRCA2 genes and is characterized by breast adenocarcinoma and/or epithelial ovarian carcinoma. LFS is associated with germline mutations in TP53; the most frequent cancer types associated with this syndrome are sarcoma, breast cancer, leukemia, brain tumors and adrenocortical carcinomas. Other cancers related to LFS are found at lower frequencies. In Brazil, especially in the southern part of the country, a specific mutation in the TP53 gene, TP53 p.R337H, occurs at a high frequency in childhood adrenocortical tumors. It has been proposed that this mutation increases breast cancer risk in southern Brazilian women.

Methods

We carried out a case-control study to determine the prevalence of the TP53 p.R337H mutation in 28 female cancer patients attended at the Cancer Genetic Counseling Service of the General Hospital of the University of São Paulo Medical School of Ribeirão Preto who fulfilled Hereditary Breast and Ovary Cancer Syndrome genetic test criteria compared to healthy woman (controls). TP53 p.R337H mutation status was determined using the High Resolution Melting (HRM) method, followed by DNA sequencing. Fisher’s test was used to compare the prevalence of TP53 p.R337H in the patient and control groups.

Results

Two of the breast cancer cases (7.1%) and none of the controls carried the TP53 p.R337H mutation. At the time of the investigation, both cases fulfilled testing criteria for Hereditary Breast and Ovary Cancer Syndrome but not Li-Fraumeni or Li-Fraumeni-like Syndrome, based on genetic testing criteria of NCCN Clinical Practice Guidelines in Oncology (v.1.2010).

Conclusions

We suggest that genetic screening of Brazilian breast cancer patients who fulfill Hereditary Breast and Ovary Cancer Syndrome criteria and have a family history that includes other tumors of the LFS/LFL spectrum be tested for the TP53 p.R337H mutation.
  相似文献   
190.
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