Objective To explore the etiology and pathogenesis of Hirschsprung disease(HD) and the role of nitric oxide in pathophysiology of HD. Methods The whole amount preparations of dilative and transitional segments were stained by NADPH\|diaphorase histochemistry mothod,and colonic walls were digested by dispase. Then the NOS positive nervous structure were observed by light and scanning electron microscope. Results In dilative segment, under light microscope, ganglion and neuron were bigger and more darkly stained. Intraganglionic neurons distributed mostly in peripheral area of ganglion and basal part of ganglionic fiber bundles. Under scanning electron microscope, the neurons were denser, more nerve fibers from them and connected with each other in all dimensions. And more transverse connected fibers between neurons which were arranged along muscle fibers. Myenteric plexus even connected with the submucosal plexus by nerve fibers which passed through circular muscle layer. In transitional segment, under light microscope, intraganglionic neurons cytoplasm were lightly stained and also variedly. The ganglion and neurons of the segment were smaller, and the fibers from them were thinner and paler than those of the dilative segment. Under scanning electron microscope, neurons' density was lower, the fiber connection between neurons and muscle fibers/neurons was lesser. In the transitional segment, neurons and nerve fibers were distributed linearly along the longitudinal muscle fibers. Conclusion Our results indicated that an intimate relationship existed between the development of Hirschsprung disease and abnormal distribution and metabolism of NOS positive neuron in colonic wall. [

Objective:To know the critical care resources of the different class-hospitals in Guizhou Province, China, and to provide the direction and evidence for quality improvement and discipline construction of critical care medicine in Guizhou Province.Methods:The resource status of the departments of intensive care unit (ICU) in Guizhou Province was obtained through form filling and/or field investigation. The forms were filled and submitted from May 2017 to February 2018, and the field investigation (some of the hospitals) was carried out in March 2018. The data of hospitals in Guizhou Province in 2018, was obtained from the official website of Health Committee of Guizhou Province, which was released online on November 28th, 2019. The obtained data were summarized and analyzed according to different aspects such asthe status of ICU construction, main equipment configuration and technology implementation.Results:There were 39 third-class hospitals and 77 second-class hospitals included in this study, which accounted for 76.5% (39/51) of third-class public hospitals and 50.0% (77/154) of second-class public hospitals respectively. Among them, there were 86.8% (33/38) of third-class general hospitals and 50.4% (69/137) of second-class general hospitals respectively. In terms of ICU construction, compared with the ICUs of second-class hospitals, the ICUs of third-class hospitals were established earlier [years: 2011 (2008, 2012) vs. 2013 (2011, 2015), P < 0.01], had more ICU beds, doctors and nurses [15 (11, 20) vs. 8 (6, 10), 9 (8, 11) vs. 6 (5, 7), 25 (20, 41) vs. 15 (12, 19), respectively, all P < 0.01]. However, there were no significant differences regarding the doctor-bed ratio and the nurse-bed ratio in ICUs between second-class hospitals and third-class hospitals. In terms of main equipment configuration, compared with the ICUs of second-class hospitals, the ICUs of third-class hospitals had more ventilators, higher ratio of ventilators to beds, more infusion pumps, higher ratio of infusion pumps to beds, more monitor, gastrointestinal nutrition pumps and single rooms, and higher proportion of ICUs equipped with negative pressure rooms [ventilators: 14 (10, 18) vs. 6 (4, 8), ratio of ventilators to beds: 1.0 (0.7, 1.1) vs. 0.8 (0.6, 1.0), infusion pumps: 10 (6, 20) vs. 5 (3, 8), ratio of infusion pumps to beds: 0.8 (0.0, 1.0) vs. 0.0 (0.0, 0.4), monitor: 18 (13, 24) vs. 9 (6, 12), gastrointestinal nutrition pumps: 2 (1, 5) vs. 1 (0, 3), single rooms: 2 (1, 3) vs. 1 (0, 3), proportion of ICUs equipped with negative pressure rooms: 53.8% (21/39) vs. 31.5% (23/73), respectively, all P < 0.05]. Furthermore, there were higher proportions of ICUs equipped with portable ventilator, pulse indicator continuous cardiac output monitoring (PiCCO), intra-aortic balloon pump (IABP), extra-corporeal membrane oxygenation (ECMO), B ultrasound machine, bronchoscope, pressure of end-tidal carbondioxide (P ETCO 2) monitoring, bispectral index (BIS) monitoring, bedside gastroscopy, the apparatus used for the prevention of deep vein thrombosis of lower extremity in third-class hospitals than in second-class hospitals [portable ventilator: 86.7% (26/30) vs. 59.6% (28/47), 43.3% (13/30) vs. 1.5% (1/66), 14.3% (4/28) vs. 0% (0/65), 10.7% (3/28) vs. 0% (0/65), 62.5% (20/32) vs. 37.3% (25/67), 97.1% (33/34) vs. 63.6% (42/66), 60.6% (20/33) vs. 28.4% (19/67), 17.2% (5/29) vs. 0% (0/65), 27.6% (8/29) vs. 1.5% (1/65), 77.4% (24/31) vs. 52.3% (34/65), respectively, all P < 0.05]. In terms of skills development, there were more ICUs carried out intracranial pressure monitoring, abdominal pressure monitoring, ultrasound diagnosis, bronchoscope examination and treatment and blood purification in third-class hospitals than in second-class hospitals [31.6% (12/38) vs. 14.7% (11/75), 75.7% (28/37) vs. 38.6% (27/70), 61.5% (24/39) vs. 24.3% (18/74), 89.7% (35/39) vs. 45.9% (34/74), 92.3% (36/39) vs. 48.6% (36/74), respectively, all P < 0.05]. Conclusions:The data were mainly derived from public general hospitals in Guizhou Province. Compared with the ICUs of second-class hospitals, the ICUs of third-class hospitals were founded earlier and larger, had better hardware configuration and could carry out more skills. However, the human resource situations were similar between second-class hospitals and third-class hospitals. Both second-class hospitals and third-class hospitals have a need to improve the allocation of manpower and equipment and expand various skills in ICUs, while it is more urgent for second-class hospitals.