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In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need.  相似文献   
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Nine wrists in eight patients were treated surgically between 1988 and 2003 for symptomatic Madelung's deformity. The pain of involved wrist followed by forearm deformation fulfilled criteria for surgery. Closing wedge osteotomy of the distal radius were carried out eight times accompanied by shortening of the ulna (four patients), excision of the distal ulna (one patient), and no ulnar surgery (three patients). Pain relieved after surgery. The follow up period ranged from 1 to 9.5 years. No pour results were stated in subjective patient's estimation during final check up. Wrist appearance were stated to be satisfactory. Limitation of the range of motion concerning supination and pronation of the forearm were stated invariably. X-ray retrospective assessment of the inclination angle, lunate coverage and presence of arthritic changes were conducted. Time and method of surgical treatment for Madelung's deformity should be considered individually.  相似文献   
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PURPOSE: A 10-year retrospective study was undertaken of all patients treated for facial gunshot and shrapnel wounds at our medical center to evaluate the outcomes and assess the results of simultaneous management to treat the hard and soft tissue injuries primarily. PATIENTS AND METHODS: A total of 44 patients were treated. Medical documentation of the patients was compiled. All maxillofacial gunshot, shrapnel, and warfare injuries were treated by the oral and maxillofacial surgeon. Other concomitant bodily injuries were treated by pertinent consultant specialists. Patients ranged in age from 8 to 53 years, with a mean age of 24.7 years. Maxillofacial hard and soft tissue injuries were treated definitively in the first operation except when gross contamination, infection, extensive comminution, or general condition precluded this. RESULTS: There were 2 shotgun, 28 bullet, 10 shrapnel, 3 land mine, and 1 breech block injuries. Overall postadmission mortality in this series was 2.2%. Of the 97.7% of the patients who had an injury to the underlying craniofacial skeleton, all required surgical intervention. The soft tissue and underlying bony injuries were addressed concomitantly (in a single stage at the time of primary surgical debridement) in 86.3% of the patients. Nine percent of the patients had a tracheostomy emergently for management of the airway, 6.8% had an intracranial injury, and 2.2% of them required neurosurgery. In the series, 4.5% of the patients had neck wounds that required exploration. Comprehensive treatment was rendered in 1 to 3 major operations (average, 1.5). CONCLUSION: All patients in this series required surgical intervention for treatment of their facial gunshot wounds. Primary treatment of hard and soft tissue injuries of the face at the time of surgical debridement was possible in the majority of our patients. This minimized the number of admissions and did not bear a higher complication rate than other reported series that advocate multiple staged operations to treat such injuries despite the fact that, in our series, flaps were also mobilized for wound closure in the primary phase.  相似文献   
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We report a case of a prenatally diagnosed infratentorial subdural hemorrhage. The hematoma located in the posterior cerebral fossa was detected by conventional ultrasound at 24 weeks of gestation. Intrauterine magnetic resonance imaging confirmed the diagnosis. Autopsy of the fetus revealed a well-circumscribed subdural hematoma. The prenatal findings of intracranial bleeding located in the posterior fossa and the prognosis of such cases are discussed.  相似文献   
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Summary The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF) technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences, the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First, the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution, measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials of CE-MRA procedures.   相似文献   
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This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells.  相似文献   
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