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51.
The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure–EEM relationships and kinetics revealed that the components extracted from EEM–PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM–PARAFAC methodology.

Drug quality and assurance changes with time under the influence of a variety of environmental factors, such as light, temperature, and moisture.  相似文献   
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Cardiac catheterization of childhood pulmonary arterial hypertension (PAH) is used to assess the severity of the disease as well as prognosis, selection of the most adequate pulmonary vasodilators, and evaluation of effectiveness. Sudden deterioration of cardiovascular hemodynamics, however, can be easily induced by pain, patient agitation, catheter manipulation, and by vasodilator provocation tests; these could trigger a pulmonary hypertension crisis, vagotony, respiratory distress, and hemoptysis resulting in critical complications, including death. Those patients with New York Heart Association functional class IV are at an especially high risk. It is noteworthy that pulmonary arteriography is a contraindication in patients with PAH. In a review of 7218 adult patients, 76 (1.1%) serious complications, including four deaths, were reported; with regard to the pediatric patients, 29 (10.7%) out of 270 patients with complications, including one with cardiogenic shock requiring cardiopulmonary resuscitation in addition to minor complications, were reported. To prevent serious complications, basic and routine precautions, such as oxygen and concomitant transcutaneous oxygen saturation and electrocardiogram monitoring during transportation to and from the catheter laboratory, are mandatory. Furthermore, the cooperation of experienced physicians and well informed medical staff in addition to meticulous preparation, for example, calculation of prior doses of catecholamine and confirmation of the presence of emergency equipment, is required.  相似文献   
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Purpose Although many reports support stimulated in vitro fertilization, several patients do not respond to it well. Furthermore, stimulated treatment could be associated with reduced ovarian response. We describe three successful cases involving patients of advanced age from whom dominant follicles were retrieved during the natural cycle. Materials and methods All patients had failed to bear children through stimulated in vitro fertilization. In case 1, a follicle was retrieved after a gonadotropin-releasing hormone agonist was used to induce luteinizing hormone surge. In cases 2 and 3, pregnancy was achieved via completely natural cycles. Results One embryo was transferred every 16 cycles. Ongoing pregnancy—defined as pregnancy progressing beyond gestation week 9—was established in three cycles. The patients successfully delivered and had uneventful neonatal courses. Conclusion Mature oocyte retrieval followed by natural rather than stimulated in vitro fertilization might be a potential treatment for patients of advanced age when stimulated in vitro fertilization has been repeatedly unsuccessful. Capsule We describe three successful pregnancies and deliveries achieved via natural IVF cycles: the patients were older than 37 years with repeated failures by stimulated IVF.  相似文献   
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Scrub typhus has struck back, albeit with renewed vigour, impacting areas with previously known endemicity as also impressing newer expanses. It is not surprising, therefore, that Scrub typhus has emerged as a leading cause of public health concern globally as well as in India, but are we ready to take on the challenge?Over the last decade, there has been a global increase in the number of outbreaks of Scrub typhus, be it the military occupied areas or the civil population at large. The innumerable outbreaks of Scrub typhus, although disconcerting, have nonetheless contributed phenomenally towards better understanding of the dynamics of scrub typhus. There have been significant contributions to awareness of the disease amongst medical professionals, scrub typhus as a cause of Acute Undifferentiated Febrile Illness (AUFI) and newer clinical manifestation – Acute Encephalitis Syndrome (AES), availability and advances in diagnostics and management, man-vector-pathogen interactions, new records of Leptotrombidium species, newer vectors and Orientia species.Antigenic diversity and the varied clinical presentation of scrub typhus, absence of scrub typhus surveillance system and a lack of political will to recognize the disease as one of the important reemerging public health problem are areas seeking concerted deliberations and actions so that the challenges posed by scrub typhus can be addressed.  相似文献   
56.
Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.  相似文献   
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The fear of serious complications, such as a necrotic conduit caused by an impaired blood circulation can arise when replacing the esophagus with an intestinal conduit. The aim of this paper is to present effective superdrainage of an intestinal conduit using an inferior mesenteric vein (IMV) interposition graft. In 2008, we performed superdrainage of the ileocolic vein to the internal jugular vein interposed by an IMV graft in replacing the esophagus with the right hemicolon for advanced thoracic esophageal cancer in three patients with a synchronous gastric cancer or a previous gastrectomy. No leakage at the enteric anastomoses occurred. Neither ischemic lesions in these intestinal conduits nor complications caused by harvesting an IMV graft were observed. Superdrainage of the ileocolic vein to the internal jugular vein interposed by an IMV graft effectively improves the blood circulation in intestinal conduits brought up to the neck as an esophageal replacement.  相似文献   
60.
Appropriate semen processing and assessment are critical for successful infertility treatment. We investigated whether laboratory procedures including semen preparation and incubation affect sperm DNA integrity. A total of 153 infertile men were involved. Conventional semen parameters and sperm chromatin structure assay (SCSA) parameters, that is, DNA fragmentation index (%DFI) and high DNA stainability (%HDS), were assessed on the flesh ejaculated semen samples, which were treated and incubated under different conditions. Negative correlations were identified between the %DFI and sperm concentration, motility, progressive motility and morphology. A lower percentage of DFI was detected in spermatozoa when density gradient centrifugation (DGC) was followed by swimup treatment in comparison with DGC alone (P 〈 0.01). Although the %DFI increased in a time-dependent manner with incubation both at room temperature (RT) and at 37℃ in air, the %DFI after 24 h at RT was significantly lower than that at 37℃ (P 〈 0.05). Incubation with 5% CO2 was effective in maintaining sperm motility (P 〈 0.01); however, it induced further elevation of %DFI (P 〈 0.001). Thus, sperm DNA damage was associated with longer incubation periods. Interestingly, common culture conditions, such as maintaining pH and temperature, compromised the sperm DNA integrity.  相似文献   
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