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11.
Hogge  DE; Humphries  RK 《Blood》1987,69(2):611-617
To study the feasibility of using retroviruses for gene transfer into human hemopoietic cells, various cell types were exposed to virus carrying the gene for neomycin resistance (neor). In preliminary studies using K562 cells as targets, we found that high viral titer and co-cultivation with viral producer cells rather than incubation in medium exposed to viral producer cells were important variables for achieving high frequencies of G418 resistant (G418r) colonies. The maximum frequency of G418r K562 colonies after co-cultivation with cells producing a neor virus titer of 4 X 10(6) cfu/mL was 60%. When primary human progenitors from normal marrow, fetal liver, or chronic myelogenous leukemia blood were exposed to high titer viral stocks, both with and without helper virus, under conditions optimized for K562 cells, maximum frequencies of G418r colonies were 3% to 16% for granulocyte macrophage progenitors and 2% to 6% for primitive erythroid progenitors. The presence of the neor gene in both G418r K562 and primary hemopoietic colonies was verified by Southern blot. Expression of the neor gene was shown by RNA spot blot. These data demonstrate efficient transfer and expression of the neor gene in both K562 cells and primary human hemopoietic cells from normal and leukemic individuals.  相似文献   
12.
Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
13.
The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.  相似文献   
14.
15.
Background/aimDuring laparoscopic cholecystectomy operations, increases in intraabdominal, intrathoracic, and intracranial pressures (ICP) can be seen after pneumoperitoneum created for surgical imaging. Orbital ultrasonography (USG), which has been developed in recent years, is a method that can evaluate the ICP by measuring the optic nerve sheath diameter (ONSD) from the eyeball.In our study, we aimed to evaluate whether different intraabdominal pressure values created during laparoscopic cholecystectomy operations correlate with ICP by measuring ONSD.Materials and methodsThe study included a total of 90 patients with American Society of Anesthesiologists (ASA) physical status classification I (ASA I) and II (ASA II) and ages from 18 to 65 years with laparoscopic cholecystectomy planned.After the patients were intubated, at the 5th min, bilateral ONSD measurements were performed. The same measurements were performed at the 15th and 30th min after CO2 insufflation and additionally 10 min after CO2 was released at the end of the operation. During intrabdominal CO2 insufflation, patients with 10 mmHg pressure applied comprised Group 1, patients with 12 mmHg pressure applied comprised Group 2, and patients with 14 mmHg pressure applied comprised Group 3.Results The study was completed with 89 patients, 51 female and 38 males. One patient was excluded from the study due to erroneous values. The variations in ONSD measured in the right-left eye before pneumoperitoneum and at the 15th and 30th min after abdominal CO2 insufflation were observed to be statistically significant (p < 0.01). In all three groups, the right and left eye ONSD values were not identified to be statistically significantly different (p > 0.01).A significant increase was observed in ONSD values in direct proportion to the increase in intraabdominal pressure in patients undergoing laparoscopic cholecystectomy surgery.Conclusion USG-guided ONSD measurements appear be a guide to ensure optimization of intraabdominal pressures and safe anesthesia administration for patients, especially those at risk of ICP increase, during laparoscopic surgery.  相似文献   
16.
Background/aim The aim of the study was to carry out the cultural adaptation and translation of the ICU mobility scale (IMS) into Turkish and research the psychometric properties.Materials and methods This study was based on methodological design. The IMS was translated from English to the Turkish through a regularised translation process. Two physiotherapists assessed patients independently in the coronary intensive care unit. The measures such as construct validity, intra and interrater reliability, and internal consistency of the IMS Turkish version were assessed. Results A total of 70 intensive care patients were included in the study. The intrarater and interrater reliability of the IMS was excellent. The weighted Kappa value was 0.92 (0.87–0.96) for the intrarater reliability, and 0.87 (0.80–0.93) for the interrater reliability. There were significant correlations between the IMS and functional status score for the intensive care unit (r = 0.83), Perme intensive care unit mobility score (r = 0.84), Katz activities of daily living (r = 0.73), handgrip strength (r = 0.62), knee extension strength (r = 0.46), and age (r = –0.44).Conclusion This study suggests that the IMS Turkish version is a reliable and valid scale for assessing functional status and mobility level in ICU patients.  相似文献   
17.
Background/aimmiRNAs control various biological functions, such as cell proliferation, differentiation, signaling pathways, apoptosis and metabolism. Recently, it has been shown that there is a relationship between changes in miRNA expression and the development of acromegaly. Studies are needed to identify new disease-specific miRNAs. The aim of the current study is to evaluate plasma miR-29c-3p, miR-31-5p and miR-18a-5p steady-state levels in acromegaly. Another aim is to investigate whether there is a difference in the levels of these miRNAs in patients with inadequate control and controlled acromegaly with somatostatin analog (SSA) therapy. These miRNAs targeting the IGF-1 gene were determined by in silico estimation.Materials and methodsThe study included 30 healthy controls (HC) and 20 patients with acromegaly. Anterior pituitary functions and disease activities of patients with acromegaly were evaluated at the time of study. The miR-29c-3p, miR-31-5p and miR-18a-5p levels were measured using quantitative real-time PCR (RT-qPCR).ResultsThe expression level of miR-29c-3p was significantly lower in patients with acromegaly compared to the HC group (p < 0.001). This downregulation was more pronounced in patients with inadequately controlled acromegaly than in patients with acromegaly controlled with somatostatin analogues (SSA) therapy (p = 0.016). Univariate logistic regression analysis results showed that down regulation of miR-29c-3p expression increases the risk of developing acromegaly [OR (95% Cl) = 1.605 (1.142-2.257), p = 0.006]. There was no significant difference between the groups in terms of miR-31-5p and miR-18a-5p expression levels (p = 0.375 and p = 0.649, respectively). ConclusionPlasma miR-29c-3p expression level is downregulated in patients with acromegaly, and this is more pronounced in patients with inadequate control.  相似文献   
18.
Fraser  CC; Eaves  CJ; Szilvassy  SJ; Humphries  RK 《Blood》1990,76(6):1071-1076
A large number of biologic, technological, and clinical studies await the development of procedures that will allow totipotent hematopoietic stem cells to be expanded in vitro. Previous work has suggested that hematopoiesis can be reconstituted using transplants of cells from long- term marrow cultures. We have used retrovirus mediated gene transfer to demonstrate that marked totipotent hematopoietic stem cells are both maintained and can be amplified in such cultures, and then subsequently regenerate and sustain lympho-myeloid hematopoiesis in irradiated recipients. Marrow cells from 5-fluorouracil-treated male mice were infected with a recombinant virus carrying the neomycin resistence gene and seeded onto irradiated adherent layers of pre-established, long- term marrow cultures of female origin. At 4 weeks, cells from individual cultures were transplanted into single or multiple female recipients. Southern blot analysis of hematopoietic tissue 45 days posttransplantation showed retrovirally marked clones common to lymphoid and myeloid tissues in 14 of 23 mice examined. Strikingly, for 3 of 4 long-term cultures, multiple recipients of cells from a single flask showed marrow and thymus repopulation with the same unique retrovirally marked clone. These results establish the feasibility of retroviral-marking techniques to demonstrate the maintenance of totipotent lympho-myeloid stem cells for at least 4 weeks in the long- term marrow culture system and provide the first evidence of their proliferation in vitro. Therefore, such cultures may serve as a starting point for identifying factors that stimulate totipotent hematopoietic stem cell expansion.  相似文献   
19.
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary.  相似文献   
20.
Pancreas divisum: thin-section CT   总被引:1,自引:0,他引:1  
Twelve patients with known pancreas divisum underwent thin-section computed tomography (CT) to determine the capability of CT to depict this pancreatic anomaly. Focal pancreatic enlargement was present in five patients. Two distinct pancreatic moieties separated by a fat cleft were noted in three patients; a fourth patient had focal atrophy in the distribution of the dorsal pancreas. The two pancreatic moieties were identified at the same craniocaudal level in all four of these patients. The dorsal duct was depicted in all 12 patients, while the short ventral duct was seen in only five of the 12 patients. Failure of the ventral and dorsal pancreatic ducts to fuse was identified in all five patients in whom both ducts were seen. CT may not enable specific diagnosis of pancreas divisum in the majority of patients. If, however, distinct pancreatic moieties or unfused ductal systems are evident, the diagnosis may be confidently suggested.  相似文献   
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