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The development of surgery is indebted to scientists and surgeons from various civilizations throughout history. The present study considers surgery in the ancient Persian civilization. It highlights aspects of the subject, such as findings of the first trephinated skulls in Iran; surgeons’ social class (kareto baē?aza in the Avestan language—dating back 3,000 years); surgical operations such as cesarean section and procedures to treat breast cancer; and the use of anesthetic compounds and surgical practice in the military. It is hoped that this catalogue of historical evidence of surgical practice in ancient Persian civilization will contribute to the history of surgery, as an important field in medical science.  相似文献   
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Natural products have served as inspirational scaffolds for the design and synthesis of novel antineoplastic agents. Here we present our preliminary efforts on the synthesis and biological evaluation of a new class of electrophilic steroids inspired by the naturally occurring taccalonolides. We demonstrate that these simplified analogs exhibit highly persistent antiproliferative properties similar to the taccalonolides and retain activity against resistant cancer cell lines that warrants further preclinical development.  相似文献   
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Applications in imaging and spectroscopy rely on pulse processing methods for appropriate data generation. Often, the particular method utilized does not highly impact data quality, whereas in some scenarios, such as in the presence of high count rates or high frequency pulses, this issue merits extra consideration. In the present study, a new approach for pulse processing in nuclear medicine imaging and spectroscopy is introduced and evaluated. The new non-linear recursive filter (NLRF) performs nonlinear processing of the input signal and extracts the main pulse characteristics, having the powerful ability to recover pulses that would ordinarily result in pulse pile-up. The filter design defines sampling frequencies lower than the Nyquist frequency.In the literature, for systems involving NaI(Tl) detectors and photomultiplier tubes (PMTs), with a signal bandwidth considered as 15 MHz, the sampling frequency should be at least 30 MHz (the Nyquist rate), whereas in the present work, a sampling rate of 3.3 MHz was shown to yield very promising results. This was obtained by exploiting the known shape feature instead of utilizing a general sampling algorithm. The simulation and experimental results show that the proposed filter enhances count rates in spectroscopy. With this filter, the system behaves almost identically as a general pulse detection system with a dead time considerably reduced to the new sampling time (300 ns). Furthermore, because of its unique feature for determining exact event times, the method could prove very useful in time-of-flight PET imaging.  相似文献   
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Here, we describe the isolation and characterization of the rhesus macaque homolog for human DC-SIGN, a dendritic cell-specific C-type lectin. mac-DC-SIGN is 92% identical to hu-DC-SIGN. mac-DC-SIGN preserves the virus transmission function of hu-DC-SIGN, capturing and efficiently transducing simian and human immunodeficiency virus to target CD4(+) T cells. Surprisingly, however, mac-DC-SIGN plays no discernable role in the ability of rhesus macaque dendritic cells to capture and transmit primate lentiviruses. Expression and neutralization analyses suggest that this process is DC-SIGN independent in macaque, although the participation of other lectin molecules cannot be ruled out. The ability of primate lentiviruses to effectively use human and rhesus dendritic cells in virus transmission without the cells becoming directly infected suggests that these viruses have taken advantage of a conserved dendritic cell mechanism in which DC-SIGN family molecules are significant contributors but not the only participants.  相似文献   
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Methods:We performed a matched-cohort study comparing 16 single-port robotic-assisted adrenalectomies with 16 patients from a pool of 148 laparoscopic adrenalectomies, matched for age, gender, operative side, pathology, and body mass index. All were operated on by 1 surgeon.Results:The pathology included aldosteronoma in 44% of patients, adrenocorticotropic hormone–dependent Cushing syndrome (bilateral adrenalectomy) in 19%, pheochromocytoma in 13%, and other pathology in 24%. The operative time was 183 ± 33 minutes for single-port robotic-assisted adrenalectomy and 173 ± 40 minutes for laparoscopic adrenalectomy (P = .58). The total time in the operating room was 246 ± 33 minutes for single-port robotic-assisted adrenalectomy and 240 ± 39 minutes for laparoscopic adrenalectomy (P = .57). There was 1 conversion to open adrenalectomy (6%) in each group, both because of bleeding on the right side during bilateral adrenalectomy. Two right-sided single-port robotic-assisted adrenalectomy patients required conversion to laparoscopic adrenalectomy, one because of poor visualization. There were no deaths. Complications occurred in 2 patients in each group (intensive care unit admission, prolonged ileus). Both groups had similar pain scores (mean of 3.7 on a scale from 1 to 10) on postoperative day 1, and patients in the single-port robotic-assisted adrenalectomy group used less narcotic pain medication in the first 24 hours after surgery (43 mg vs 84 mg in laparoscopic adrenalectomy group, P < .001). The differences between the single-port robotic-assisted adrenalectomy group and laparoscopic adrenalectomy group in length of stay (2.3 ± 0.5 days vs 3.1 ± 0.9 days, P = .23), percentage of patients discharged on postoperative day 1 (56% vs 31%, P = .10), and hospital cost (16% lower in single-port robotic-assisted adrenalectomy group, P = .17) did not reach statistical significance.Conclusion:Single-port robotic adrenalectomy is feasible; patients require less narcotic pain medication whereas costs appear equivalent compared with laparoscopic adrenalectomy.  相似文献   
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Objective: Isolated growth hormone deficiency (IGHD) is defined as a medical condition associated with growth failure due to insufficient production of GH or lack of GH action. Mutations in the gene encoding for GH-releasing hormone receptor (GHRHR) have been detected in patients with IGHD type IB. However, genetic defects on GHRHR causing IGHD in the Turkish population have not yet been reported. To identify mutations on GHRHR gene in a population of Turkish children with IGHD.Methods: Ninety-six Turkish children with IGHD were included in this study. Exon1-13 and exon/intron boundaries of GHRHR were amplified by suitable primers. The polymerase chain reaction products for GHRHR gene were sequenced with primers.Results: We analyzed the GHRHR gene for mutations in ninety-six patients with IGHD based on sequence results. We identified novel p.K264E, p.S317T, p.S330L, p.G369V, p.T257A and C base insertion on position 380 (c.380inserC) mutations. In 5 of the patients, the mutation was homozygote and in 1-heterozygote (p.S317T).Conclusion: Six new missense mutations and one first case of insertion mutations for the GHRHR gene are reported.  相似文献   
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