Objective To enhance recognition of the clinical and radiological features of nonaneurysmal subarachnoid hemorrhage (SAH) and its prognosis, and to provide guidance for the diagnosis and treatment in clinical practice. Methods Patients with spontaneous SAH, whose initial 3-dimensional digital subtraction angiography (DSA) were negative, received a second DSA after 2 to 3 weeks.Nonaneurysmal was diagnosed as SAH when both DSA were negative. All subjects were divided into 2 subgroups, perimesencephalic nonaneurysmal subarachnoid hemorrhage ( PNSAH ) group and nonperimesencephalic nonaneurysmal subarachnoid hemorrhage ( n-PNSAH ) group. Results Among 49 patients with nonaneurysmal SAH, 24 patients were PNSAH and 25 patients were n-PNSAH. Two patients died and 47 patients recovered and discharged with an average follow-up of 26 months. Conclusion The clinical course and prognosis of patients with PNSAH were good, better than that of patients with n-PNSAH.

Objective To investigate the Suidasia nesbitti breeding status in the ground dust flour collected in Qiqihaer City. Methods Totally,16 aliquots of ground dust flour were respectively collected from a college canteen and 15 households in Qiq-ihaer City. Then 10 g dust flour was taken from individual sample for isolation of the mites that were made of slide specimen,and the mites were identified and classified under a microscope. Results Acaroid mites were found in 15 of the 16 aliquots of sam-ples(detection rate being 93.8%),and 7 species,belonging to 6 genera under 3 families,were identified. A total of 561 heads of mites were isolated from 160 g samples,with an average breeding density of 3.51 heads/g. The most breeding mite was associ-ated with S. nesbitti. Conclusions Various species of mites are breeding in the ground dust flour in Qiqihaer City,and S. nesbit-ti occurs the most. These findings indicate that effective measures should be taken to prevent and control the harm associated with acaroid mite contamination.