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81.
The involvement of testosterone in di(2-ethylhexyl)phthalate (DEHP) induced testicular injury has been examined by coadministration of testosterone (1 mg/kg) along with DEHP (2000 mg/kg) daily for 15 days. The coadministration of testosterone and DEHP appears to have prevented the testicular injury as judged by the biochemical and histopathological changes. The sperm count and the activity of the testicular enzymes, gamma-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), sorbitol dehydrogenase (SDH), beta-glucuronidase and acid phosphatase, related with the maturation of sperm, which were significantly altered by DEHP treatment were found to be within normal levels after the combination treatment of DEHP and testosterone. The histopathological studies also showed more or less normal spermatogenic events. The results of this study have suggested the involvement of testosterone in DEHP induced testicular atrophy. 相似文献
82.
Matthew D. Li Nishanth T. Arun Mehak Aggarwal Sharut Gupta Praveer Singh Brent P. Little Dexter P. Mendoza Gustavo C.A. Corradi Marcelo S. Takahashi Suely F. Ferraciolli Marc D. Succi Min Lang Bernardo C. Bizzo Ittai Dayan Felipe C. Kitamura Jayashree Kalpathy-Cramer 《Medicine》2022,101(29)
To tune and test the generalizability of a deep learning-based model for assessment of COVID-19 lung disease severity on chest radiographs (CXRs) from different patient populations.A published convolutional Siamese neural network-based model previously trained on hospitalized patients with COVID-19 was tuned using 250 outpatient CXRs. This model produces a quantitative measure of COVID-19 lung disease severity (pulmonary x-ray severity (PXS) score). The model was evaluated on CXRs from 4 test sets, including 3 from the United States (patients hospitalized at an academic medical center (N = 154), patients hospitalized at a community hospital (N = 113), and outpatients (N = 108)) and 1 from Brazil (patients at an academic medical center emergency department (N = 303)). Radiologists from both countries independently assigned reference standard CXR severity scores, which were correlated with the PXS scores as a measure of model performance (Pearson R). The Uniform Manifold Approximation and Projection (UMAP) technique was used to visualize the neural network results.Tuning the deep learning model with outpatient data showed high model performance in 2 United States hospitalized patient datasets (R = 0.88 and R = 0.90, compared to baseline R = 0.86). Model performance was similar, though slightly lower, when tested on the United States outpatient and Brazil emergency department datasets (R = 0.86 and R = 0.85, respectively). UMAP showed that the model learned disease severity information that generalized across test sets.A deep learning model that extracts a COVID-19 severity score on CXRs showed generalizable performance across multiple populations from 2 continents, including outpatients and hospitalized patients. 相似文献
83.
OBJECTIVE: To examine whether clean catch urine specimens correlate with catheterized specimens for determination of protein/creatinine ratios in pregnant women being evaluated for preeclampsia. METHODS: Sixty pregnant women who were at least at 20 weeks of gestation were enrolled. Patients with ruptured membranes, vaginal bleeding, or urinary tract infections were excluded. Midstream clean catch urine specimens were collected. Catheterized specimens were then collected and used for clinical management. The specimens were analyzed for protein, creatinine, urinalysis, and culture. Based on sample size calculations, 60 participants were needed to detect a correlation of 0.90 with 80% power and alpha=0.05. RESULTS: Mean gestational age at enrollment was 35.9 weeks (range 23.1-41.7 weeks). Median (range) clean catch and catheterized protein/creatinine ratios were 0.204 (0.089-3.465) and 0.181 (0.067-3.335), respectively, with a correlation coefficient of 0.897 (P<.001). When results were categorized by degree of proteinuria using a cutoff of 0.3, sensitivity and specificity of the clean catch protein/creatinine ratios were 95.2% and 97.4%. When using a more conservative cutoff of 0.19, sensitivity and specificity of the clean catch protein/creatinine ratios were 96.4% and 75.0%. CONCLUSION: Clean catch and catheterized urine specimens correlate well in women with suspected preeclampsia. Routine catheterization of pregnant women is not necessary in the evaluation of preeclampsia. 相似文献
84.
Srivastava G Pilkington A Nallala D Polson DW Holt E 《Archives of gynecology and obstetrics》2007,276(5):555-557
Objective Ogilvies syndrome (OS) is a rare condition in obstetrics but occurs most commonly after caesarean section. Mortality rates
from OS can be as high as 36–50% when bowel perforation or ischemia develops which highlights the early recognition of this
condition. Early diagnosis is therefore essential to prevent serious morbidity and mortality.
Conclusion We, therefore report a case of OS after caesarean section in which early detection by senior clinicians resulted in successful
management of the condition and an excellent outcome. 相似文献
85.
Graphitic carbon nitride (g-C3N4) has emerged as a new research hotspot, attracting broad interdisciplinary attention in the form of metal-free and visible-light-responsive photocatalysts in the field of solar energy conversion and environmental remediation. These photocatalysts have evolved as attractive candidates due to their non-toxicity, chemical stability, efficient light absorption capacity in the visible and near-infrared regions, and adaptability as a platform for the fabrication of hybrid materials. This review mainly describes the latest advances in g-C3N4 photocatalysts for chemical transformations. In addition, the typical applications of g-C3N4-based photocatalysts involving organic transformation reactions are discussed (synthesis of heterocycles, hydrosulfonylation, hydration, oxygenation, arylation, coupling reactions, etc.).Graphitic carbon nitride (g-C3N4) has emerged as a new research hotspot, attracting broad interdisciplinary attention in the form of metal-free and visible-light-responsive photocatalysts. 相似文献
86.
Daniela Gmez Atria Brian T. Gaudette Jennifer Londregan Samantha Kelly Eric Perkey Anneka Allman Bhaskar Srivastava Ute Koch Freddy Radtke Burkhard Ludewig Christian W. Siebel Russell J.H. Ryan Tanner F. Robertson Janis K. Burkhardt Warren S. Pear David Allman Ivan Maillard 《The Journal of clinical investigation》2022,132(13)
87.
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89.
The concept of dose-dense chemotherapy has emerged and is based on the hypothesis that maximal chemotherapy effectiveness can be achieved by scheduling the interval of chemotherapy to correspond to the period of most rapid tumor growth, as predicted by preclinical models. The granulocyte-colony stimulating factor support has permitted the safe delivery of chemotherapy at shorter ("dose-dense") inter-treatment intervals. Several randomized trials have been conducted to test the feasibility and effectiveness of anthracycline and/or taxanes-based dose-dense strategies. They have been associated with a modest impact on disease recurrence and overall survival of patients with early-stage breast cancer. Subset analyses have suggested increased benefits for specific tumor subtypes such as hormone receptor-negative, highly proliferative or HER2 overexpressing tumors. This review article aims to outline the theoretical framework for dose-dense chemotherapy and summarizes the results of several recent clinical trials addressing this concept within neoadjuvant and adjuvant breast cancer treatment and discuss their implications for clinical practice. Further studies are needed to define the optimal regimen and the patient population that will receive the greatest benefit from dose-dense strategy. 相似文献
90.
OBJECTIVE: Glutathione-S-transferases (GSTs) are active in the detoxification of wide variety of endogenous or exogenous carcinogens. We examined the association of the GST gene polymorphism with sporadic bladder cancer patients in Northern India. MATERIAL AND METHODS: The study constituted of 106 bladder cancer cases and 370 age-matched controls. The GSTT1 and GSTM1 null genotypes were identified by multiplex PCR and GSTP1313 A/G by Polymerase Chain Reaction/Restriction Fragment Length Polymorphism method (PCR/RFLP). RESULTS: We observed non-significant association in null alleles of the GSTM1 (p = 0.611, OR = 1.12, 95% CI = 0.72-1.74 and GSTT1 (p = 0.135, OR = 1.45, 95% CI = 0.89-2.37) with risk of bladder cancer. However, the G/G genotype of the GSTP1 gene polymorphism was highly significant when compared to controls (p=0.000, OR = 7.12, 95% CI = 3.14-16.16). The combined analysis of the three risk genotypes demonstrated further increase in the risk of bladder cancer (p = 0.000, OR = 7.29 95% CI = 2.81-18.93). CONCLUSION: Our study demonstrated that GSTP1313 G/G polymorphism is a strong predisposing risk factor for bladder cancer. Combination of three GST genotypes association exhibiting gene-gene interaction further substantiates the increased risk of bladder cancer. 相似文献