Objective To investigate the prevalence of Paragonimus infection in freshwater crabs from selected areas of Yunnan Province, and to perform molecular characterization and phylogenetic analysis of the isolated parasites based on the internal transcribed spacer 2 (ITS2) and cytochrome c oxidase subunit I (COI) gene sequences. Methods Freshwater crabs were collected from both local markets and natural streams in Zhaotong City, Pu’er City, Dehong Dai and Jingpo Autonomous Prefecture, Baoshan City, Honghe Hani and Yi Autonomous Prefecture and Lincang City of Yunnan Province from May to August 2025. Paragonimus metacercariae were isolated using a sieve and sedimentation method. After morphological identification of the metacercariae, the infection rate and infection intensity of Paragonimus in freshwater crabs were calculated. Then genomic DNA was extracted from an individual metacercaria, and ITS2 and COI gene fragments were amplified using a PCR assay and sequenced. The obtained sequences were aligned with those available in the GenBank database. Genetic distances were calculated with the software MEGA 11.0 based on the Kimura 2-parameter model, and phylogenetic trees were built using the neighbour-joining method. Results A total of 600 freshwater crabs were collected, with 18 positive for Paragonimus metacercariae. The prevalence of Paragonimus infection was 12.00% (18/150) in freshwater crabs from Zhaotong City, while no Paragonimus infection was detected in crabs from other five prefectures (cities). Twenty metacercariae were recovered, with an overall infection intensity of 1.11 metacercariae per crab. Morphological observation revealed two types of Paragonimus metacercariae, including 19 resembling P. skrjabini, and 1 resembling P. paishuihoensis. Ten metacercariae of distinct morphotypes were randomly selected for molecular identification, and sequence alignment and phylogenetic analysis of ITS2 and COI genes identified 9 as P. skrjabini and 1 as P. paishuihoensis. The nine ITS2 gene sequences shared 98.34% to 100.00% homology with the reference sequence of P. skrjabini (GenBank accession number: KX129924.1), and the single ITS2 gene sequence showed 100.00% homology with the reference sequence of P. paishuihoensis (GenBank accession number: OM401939.1), while its COI sequence showed 98.80% homology with the reference sequence of P. paishuihoensis (GenBank accession number: AB679288.1). Phylogenetic analysis further confirmed that the 10 sequences were clustered separately into the clades of P. skrjabini and P. paishuihoensis. Conclusions This study reports the first detection of P. paishuihoensis in freshwater crabs from Zhaotong City, Yunnan Province, and confirms P. skrjabini as the dominant Paragonimus species in this region. Molecular identification and phylogenetic analysis based on ITS2 and COI genes are effective to distinguish Paragonimus species, which provides the scientific evidence for precise control of paragonimiasis in Yunan Province.

Laughing gas (Nitrogen monoxide) is currently abused due to its low price and easy availability. This article discussed the clinical manifestations of a patient with subacute combined degeneration of the spinal cord caused by inhalation of laughing gas. The patient developed numbness of extremities, unstable walking, and decreased serum vitamin B 12 level. MRI of the cervical spine showed abnormal signals in the lateral and posterior cords of the cervical spinal cord (C2-6) , neuroelectrophysiological examination showed peripheral nerve damage in the extremities. After treatment with vitamin B 12 supplementation, the patient's condition gradually improved. Clinicians diagnose subacute combined degeneration of the spinal cord, especially when the patient has no gastrointestinal disease, diet, malnutrition, etc., they need to carefully inquire about the history of nitrous oxide inhalation to avoid missed diagnosis.

Laughing gas (Nitrogen monoxide) is currently abused due to its low price and easy availability. This article discussed the clinical manifestations of a patient with subacute combined degeneration of the spinal cord caused by inhalation of laughing gas. The patient developed numbness of extremities, unstable walking, and decreased serum vitamin B 12 level. MRI of the cervical spine showed abnormal signals in the lateral and posterior cords of the cervical spinal cord (C2-6) , neuroelectrophysiological examination showed peripheral nerve damage in the extremities. After treatment with vitamin B 12 supplementation, the patient's condition gradually improved. Clinicians diagnose subacute combined degeneration of the spinal cord, especially when the patient has no gastrointestinal disease, diet, malnutrition, etc., they need to carefully inquire about the history of nitrous oxide inhalation to avoid missed diagnosis.

Objective To investigate the factors affecting insufficient blood collection from volunteer donors. Methods Volunteer blood donors in our hospital were divided into two groups: group A (volunteer donors from January 2001 to December 2003) and group B (volunteer donors from January to June in 2004) after improving the environment of blood collection and service quality. The cases and main affecting factors of insufficient blood collection were analysed. Results The percentage of cases with insufficient blood collection in group A and group B was 0.95% and 0.53%, respectively, which had a significant difference between the two groups (P

Objective To analyze the incidence of invasive fungal infection and the risk factor in primary acute leukemia patients.Methods Retrospectively analysis of clinical data from Jan 2007 to Jun 2008 about 80 newly diagnosed patients with acute leukemia primary treated in Peking University People's hospital.Results The incidence of invasive fungal infection is 13.8%,elderly patients、higer WBC counts and longer antibiotics treatment are the risk factor for the fungal infection.Conclusion There are high incidence of invasive fungal infection in induction therapy for primary acute leukemia,the prophylaxis therapy should be consider in high risk patients.