diff --git a/pubmed_parser/pubmed_oa_parser.py b/pubmed_parser/pubmed_oa_parser.py
index 06b4d25..d05dda9 100644
--- a/pubmed_parser/pubmed_oa_parser.py
+++ b/pubmed_parser/pubmed_oa_parser.py
@@ -145,7 +145,7 @@ def parse_pubmed_xml(path, include_path=False, nxml=False):
     pub_day_node = tree.find(".//pub-date/day")
     pub_day = pub_day_node.text if pub_day_node is not None else "01"
 
-    subjects_node = tree.findall(".//article-categories.//subj-group/subject")
+    subjects_node = tree.findall(".//article-categories//subj-group/subject")
     subjects = list()
     if subjects_node is not None:
         for s in subjects_node:

parse_pubmed_xml does not return "subjects"
**Describe the bug**
Parse PubMed OA XML information appears to have a bug with the "subjects" attribute. 

**To Reproduce**
```
dict_out = pp.parse_pubmed_xml(path)
dict_out["subjects"]
```
Will always be empty. 
https://github.com/titipata/pubmed_parser/blob/1376aa651f05662742e7e225c831c6ffda0dc91b/pubmed_parser/pubmed_oa_parser.py#L148
I believe the following change will fix the issue. 
```
subjects_node = tree.findall(".//article-categories//subj-group/subject")
```

**Expected behavior**
Should return subjects.
diff --git a/tests/test_pubmed_oa_parser.py b/tests/test_pubmed_oa_parser.py
index 768c45c..4d44d3f 100644
--- a/tests/test_pubmed_oa_parser.py
+++ b/tests/test_pubmed_oa_parser.py
@@ -14,6 +14,7 @@ def test_parse_pubmed_xml():
     assert len(parsed_xml.get("full_title")) > 0
     assert parsed_xml.get("pmc") == "3460867"
     assert parsed_xml.get("doi") == "10.1371/journal.pone.0046493"
+    assert parsed_xml.get("subjects") == "Research Article; Biology; Biochemistry; Enzymes; Enzyme Metabolism; Lipids; Fatty Acids; Glycerides; Lipid Metabolism; Neutral Lipids; Metabolism; Lipid Metabolism; Proteins; Globular Proteins; Protein Classes; Recombinant Proteins; Biotechnology; Microbiology; Bacterial Pathogens; Bacteriology; Emerging Infectious Diseases; Host-Pathogen Interaction; Microbial Growth and Development; Microbial Metabolism; Microbial Pathogens; Microbial Physiology; Proteomics; Sequence Analysis; Spectrometric Identification of Proteins"
 
 
 def test_parse_pubmed_paragraph():

pip install -e .
parse_log_pytest
requirements.txt
pytest
apt-get update apt-get install -y gcc
3.7
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
certifi @ file:///croot/certifi_1671487769961/work/certifi
charset-normalizer==3.4.1
coverage==7.2.7
exceptiongroup==1.2.2
idna==3.10
importlib-metadata==6.7.0
iniconfig==2.0.0
lxml==5.3.1
numpy==1.21.6
packaging==24.0
pluggy==1.2.0
-e git+https://github.com/titipata/pubmed_parser.git@1376aa651f05662742e7e225c831c6ffda0dc91b#egg=pubmed_parser
pytest==7.4.4
pytest-cov==4.1.0
requests==2.31.0
six==1.17.0
tomli==2.0.1
typing_extensions==4.7.1
Unidecode==1.3.8
urllib3==2.0.7
zipp==3.15.0

name: pubmed_parser
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2022.12.7=py37h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.4.4=h6a678d5_1
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=22.3.1=py37h06a4308_0
  - python=3.7.16=h7a1cb2a_0
  - readline=8.2=h5eee18b_0
  - setuptools=65.6.3=py37h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.38.4=py37h06a4308_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - charset-normalizer==3.4.1
      - coverage==7.2.7
      - exceptiongroup==1.2.2
      - idna==3.10
      - importlib-metadata==6.7.0
      - iniconfig==2.0.0
      - lxml==5.3.1
      - numpy==1.21.6
      - packaging==24.0
      - pluggy==1.2.0
      - pytest==7.4.4
      - pytest-cov==4.1.0
      - requests==2.31.0
      - six==1.17.0
      - tomli==2.0.1
      - typing-extensions==4.7.1
      - unidecode==1.3.8
      - urllib3==2.0.7
      - zipp==3.15.0
prefix: /opt/conda/envs/pubmed_parser

tests/test_pubmed_oa_parser.py::test_parse_pubmed_xml
tests/test_pubmed_oa_parser.py::test_parse_pubmed_paragraph tests/test_pubmed_oa_parser.py::test_parse_pubmed_references tests/test_pubmed_oa_parser.py::test_parse_pubmed_caption
pubmed_parser/pubmed_oa_parser.py
pubmed_parser/pubmed_oa_parser.py