OBJECTIVE To construct a predictive model for evaluating the efficacy of a triple antiemetic regimen （neurokinin- 1 receptor antagonist+5-hydroxytryptamine 3 receptor antagonist+dexamethasone） for preventing nausea and vomiting induced by highly emetogenic chemotherapy （HEC） based on interpretable deep learning algorithms. METHODS Clinical data of cancer patients who received HEC and were treated with the standard triple antiemetic regimen in the oncology department of Tianjin Medical University General Hospital from January 2018 to December 2022 were collected retrospectively. Demographic， clinical and metabolism-related variables were integrated. After data pre-processing， two deep learning algorithms （deep random forest and dense neural network） and four machine learning algorithms （support vector machine， categorical boosting， random forest and decision tree） were used to build predictive models. Subsequently， model performance evaluation and model interpretability analysis were conducted. RESULTS Among the six candidate models， the deep random forest model demonstrated the best predictive performance on the test set， with an area under the receiver operating characteristic curve of 0.850， an accuracy of 0.911， a precision of 0.805， a recall of 0.783， an F1 score of 0.793， and a Brier score of 0.075. Interpretability analysis revealed that creatinine clearance rate （Ccr） was the key predictive factor， and low Ccr levels， female gender， younger age， highly emetogenic drugs （particularly cisplatin-containing chemotherapy regimens）， and anticipatory nausea and vomiting were positively correlated with the risk of HEC-related nausea and vomiting. CONCLUSIONS The deep random forest model exhibits the best performance in predicting the efficacy of triple antiemetic regimen for preventing HEC-related nausea and vomiting. The key predictors in this model primarily include Ccr，anticipatory nausea and vomiting， gender， age， and highly emetogenic drugs.

ObjectiveTo study the mechanism of Yinchenhao Tang on the improvement of cholestatic liver injury （CLI） by inhibiting toll-like receptor 4 （TLR4）/myeloid differentiation factor 88 （MyD88）/nuclear transcription factor-κB （NF-κB） pathway via regulating farnesol X receptor （FXR）. MethodsA total of 40 Wistar male rats were randomly selected， with 10 as a blank group，and the remaining rats were subjected to the CLI model induced by alpha-naphthalene isothiocyanate （ANIT）. After modeling，they were randomly divided into the model group， the ursodeoxycholic acid （0.1 g·kg^-1） group and the Yinchenhao Tang （9.23 g·kg^-1） group，with 10 animals in each group. Each administration group was given the corresponding drug by intragastric administration for three consecutive days. Alanine aminotransferase （ALT），aspartate aminotransferase （AST），alkaline phosphatase （ALP），γ-glutamyl transpeptidase （γ-GT），total bile acid （TBA），total bilirubin （TBil） and direct bilirubin （DBil） levels in serum were detected. Tumor necrosis factor-α （TNF-α），interleukin-1β （IL-1β），and interleukin-6 （IL-6） levels in liver tissue were detected. Real-time PCR was used to detect the mRNA expression of FXR，TLR4，MyD88，NF-κB，F4/80，TNF-α，IL-1β and IL-6 in liver tissue. Western blot was used to detect protein expression of FXR，TLR4，MyD88 and NF-κB in liver tissue. The histopathological changes of the liver were observed by hematoxylin-eosin （HE） staining. ResultsCompared with those in the blank group，ALT，AST，ALP，γ-GT，TBA，TBil and DBil levels in serum of rats in the model group were significantly increased （P<0.01）. The levels and mRNA expression of TNF-α，IL-1β and IL-6 in liver tissue were significantly increased （P<0.01），and the mRNA and protein expressions of FXR in liver tissue were decreased （P<0.01）. The mRNA and protein expressions of TLR4，MyD88 and NF-κB and the mRNA expression of F4/80 were obviously increased （P<0.05，P<0.01）. Hepatic histopathology showed inflammatory cell infiltration and proliferative changes of bile duct epithelial cells. Compared with those in the model group，ALT，ALP，γ-GT，TBA，TBil and DBil levels in serum of rats in the ursodeoxycholic acid group were obviously decreased （P<0.05，P<0.01），and the levels and mRNA expression of TNF-α，IL-1β and IL-6 in liver tissue were obviously decreased （P<0.05，P<0.01）. The mRNA and protein expressions of TLR4，MyD88 and NF-κB and the mRNA expression of F4/80 in liver tissue were obviously decreased （P<0.05，P<0.01）. ALT，AST，ALP，γ-GT，TBA，TBil and DBil levels in the serum of rats in the Yinchenhao Tang group were obviously decreased （P<0.05，P<0.01），and the levels and mRNA expression of TNF-α，IL-1β and IL-6 in liver tissue were obviously decreased （P<0.01）. The mRNA and protein expressions of FXR in liver tissue were significantly increased，and the mRNA expressions of TLR4，MyD88，NF-κB，and F4/80， as well as the protein expressions of TLR4 and NF-κB were obviously decreased （P<0.05，P<0.01）. The inflammatory cell infiltration of liver tissue and the proliferation of bile duct epithelial cells decreased. ConclusionYinchenhao Tang has an obvious protective effect on CLI，and its mechanism may be related to regulating FXR to inhibit TLR4/MyD88/NF-κB pathway-mediated inflammatory response.

OBJECTIVE To preliminarily investigate the antiasthmatic effect and mechanism of Ephedrae Herba-Armeniacae Semen Amarum herb pair on the respiratory center. METHODS Male SD rats were randomly divided into blank group， model group， dexamethasone group （positive control）， and Ephedrae Herba-Armeniacae Semen Amarum 2∶1， 1∶1 and 1∶2 groups. Rats in each group were administered different ratios of the herb pair decoction [all at 18 g （crude drug）/kg]， dexamethasone suspension （0.5 mg/kg）， or normal saline intragastrically twice daily for seven consecutive days. Forty minutes after the last administration， medicated cerebrospinal fluid was collected to determine the content of effective components entering the brain. One and a half hours after the last administration， the nucleus tractus solitarius （NTS） was located using a stereotaxic apparatus. Histamine phosphate （1 μL） was injected into the NTS region at a constant rate of 1 μL/min using a 10 μL microsyringe to induce excitation of the respiratory center in rats； the blank group was injected with normal saline. The contents of neurotransmitters [nerve growth factor （NGF）， substance P （SP）， norepinephrine （NA）， 5-hydroxytryptamine （5-HT） and acetylcholine （Ach）] in the medulla oblongata brain tissue were detected. The mRNA expressions of neurokinin-1 receptor （NK-1R）， p38 mitogen-activated protein kinase （MAPK）， and c-fos in the medulla oblongata， as well as the protein expressions of NK-1R， p38 MAPK， and c-fos in the NTS region， were determined. RESULTS The main active components of Ephedrae Herba-Armeniacae Semen Amarum herb pair entering the brain were ephedrine， pseudoephedrine， and methylephedrine. Compared with blank group， the contents of NGF， SP， NA， 5-HT and Ach， and the relative expression levels of NK-1R， p38 MAPK， and c-fos mRNA and protein were significantly increased in the model group （ P ＜0.01）. Compared with model group， Ephedrae Herba-Armeniacae Semen Amarum herb pair groups with different ratios significantly reduced the neurotransmitter contents and the relative expression levels of NK-1R， p38 MAPK， and c-fos mRNA and protein （ P ＜0.01）， with the 2∶1 Ephedrae Herba-Armeniacae Semen Amarum herb pair and 1∶1 mass ratios showing relatively better effects. CONCLUSIONS Ephedrae Herba alkaloids are the main active components in affecting the function of the respiratory center. The herb pair groups with a larger proportion of Ephedrae Herba exhibit stronger effects. Ephedrae Herba-Armeniacae Semen Amarum herb pair can reduce the excitability of the respiratory center by down-regulating the expression of the NK-1R/MAPK/c-fos pathway in the NTS and decreasing the abnormal release of neurotransmitters such as NGF and SP.

Background Meteorological factors are among the key extrinsic triggers for the onset and exacerbation of cardiovascular and cerebrovascular diseases (CVD). Against the backdrop of sustained global warming, elucidating the impact of ambient temperature and atmospheric pressure on CVD, especially on pre-hospital CVD emergent events, has become imperative for evidence-based prevention and emergency preparedness. Objective To quantify the temporal trends of daily mean temperature and atmospheric pressure and their associations with pre-hospital CVD emergent events in Yantai, and to explore effect modification by demographic subgroups and geographic areas, thereby providing an empirical basis for the rational allocation of emergency medical resources. Methods Pre-hospital CVD emergency data from January 1, 2016 to December 31, 2022 were selected from the Yantai 120 Emergency Medical Command System. Synchronous meteorological factors and environmental pollutant data were obtained from the websites of the National Oceanic and Atmospheric Administration and the National Centers for Environmental Information of the United States. Time-series analysis combined with distributed lag non-linear model was used to analyze the association between daily temperature, atmospheric pressure, and pre-hospital CVD emergencies. Average annual percentage changes (AAPC) were calculated using Joinpoint (version 5.2.0.0) to reflect temporal trends. Spearman correlation analysis was employed to screen variables with low collinearity for inclusion in the multi-pollutant adjusted models. Results From 2016 to 2022, a total of 268275 pre-hospital CVD emergency cases were recorded in Yantai City, showing an increasing annual trend (AAPC=7.16%, P=0.002). Emergency volume, daily temperature, atmospheric pressure, and PM₁₀ displayed marked seasonal patterns, with summer bottoms and winter peaks for emergencies, daily temperature higher in summer and lower in winter, and the inverse for atmospheric pressure. Correlation analysis showed that both daily temperature and atmospheric pressure were positively correlated with O₃, with correlation coefficients of 0.745 and 0.723, respectively; negatively correlated with PM_2.5, with correlation coefficients of −0.246 and −0.235, respectively; and negatively correlated with PM₁₀, with correlation coefficients of −0.241 and −0.229, respectively (P < 0.05). A U-shaped correlation was revealed between daily temperature and pre-hospital CVD emergency risk. Using 24 °C as the reference, risk was elevated at both low and high daily temperatures, with the strongest cold effect at –11 ℃ (RR=1.53, 95%CI: 1.35, 1.73) and strongest heat effect at 30 ℃ (RR=1.06, 95%CI: 1.01, 1.11); cold effects were prolonged (lag0–14d) compared to heat effects. Atmospheric pressure exhibited a positive association with emergencies; using a median of 1012.2 hPa as the reference, the maximum risk occurred at 1037 hPa (RR=1.25, 95%CI: 1.03, 1.52), with a 0–5 d lag. In the subgroup analysis, the impact of low temperature was more pronounced among females (RR_{−9 ℃}=1.66), people over 60 years (RR_{−9 ℃}=1.91), and rural residents (RR_{−9 ℃}=1.76). High atmospheric pressure significantly increased the risk of pre-hospital CVD emergency among females (RR_{1035 hPa}=1.54), people under 18 years (RR_{1035 hPa}=3.62), and rural residents (RR_{1035 hPa}=1.46). The sensitivity analysis results indicated that, after excluding the impact of pandemic and the degrees of freedom for time variations, the effects of daily average temperature and atmospheric pressure on pre-hospital CVD emergency volume were consistent with the primary analysis findings. Conclusion Both non-optimal temperature and atmospheric pressure significantly increase the pre-hospital CVD emergency volume; therefore, emergency medical services should develop targeted response protocols, optimize resource allocation, and intensify public health education to mitigate the pre-hospital burden attributable to temperature and pressure fluctuations.

ObjectiveMicrotube associated protein-2 （MAP-2）， alpha-tubulin （α-tubulin）， and synaptophysin （SYP） are important proteins in neuronal signal communication. This paper observed the effects of modified Zhigancao Tang on the expression of serum α-Synuclein （α-Syn） and its oligomers， MAP-2， α-tubulin， and SYP of patients with liver and kidney deficiency of Parkinson's disease （PD）， analyzed their correlation， and evaluated the therapeutic effect of modified Zhigancao Tang in patients with liver and kidney deficiency of PD based on α-Syn transmission pathway mediated by neuronal communication in vivo. MethodsA total of 60 patients with PD who met the inclusion criteria were randomly divided into a treatment group （30 cases） and a control group （30 cases）. Both groups were treated on the basis of PD medicine， and the treatment group was treated with modified Zhigancao Tang. Both groups were treated for 12 weeks. The changes in UPDRS score， TCM syndrome score， and expression of serum α-Syn and its oligomers， MAP-2， α-tubulin， and SYP were observed before and after 12 weeks of treatment in each group. The correlation between the above-mentioned serum biological indexes and the levels of serum α-Syn and its oligomers was analyzed. ResultsAfter treatment， the TCM syndrome score， UPDRS score， UPDRS-Ⅱ score， and UPDRS-Ⅲ score of the treatment group were significantly decreased （P<0.05， P<0.01）. The UPDRS score， UPDRS-Ⅱ score， and UPDRS-Ⅲ scores in the treatment group were significantly decreased compared with those in the control group after treatment （P<0.05）. After treatment， the total effective rate of the control group was 63.3% （19/30）， and that of the treatment group was 86.7% （26/30）. The clinical effect of the observation group was better than the control group （Z=-2.03， P<0.05）. The total effective rate of the observation group was better than that of the control group， and the difference was statistically significant （χ²=5.136， P<0.05）. After treatment， the oligomer level of serum α-Syn and MAP-2 level in the treatment group were significantly decreased （P<0.05， P<0.01）. The levels of serum α-Syn and its oligomers， as well as α-tubulin in the treatment group， were significantly decreased compared with those in the control group after treatment （P<0.05， P<0.01）. Serum α-Syn was correlated with serum MAP-2 and α-Syn oligomer in patients with PD （P<0.05， P<0.01） but not correlated with serum SYP . Serum α-Syn oligomers of patients with PD were correlated with serum MAP-2 and α-tubulin （P<0.05， P<0.01） but not correlated with serum SYP level. Serum SYP of patients with PD was correlated with serum MAP-2 （P<0.05）. ConclusionModified Zhigancao Tang has a therapeutic effect on patients with liver and kidney deficiency of PD by inhibiting the production of α-Syn oligomers and intervening α-Syn microtubule transport pathway in vivo.

OBJECTIVE: To investigate the frequency and related factors of ineffective triggering (IT) and double triggering (DT) in patients with acute brain injury undergoing invasive mechanical ventilation. METHODS: A retrospective cohort study was conducted using data from a single-center observational trial. Patients with acute brain injury [traumatic brain injury, stroke, and post-craniotomy for brain tumors] undergoing mechanical ventilation in the intensive care unit (ICU) of Beijing Tiantan Hospital, Capital Medical University between June 2017 and July 2019 were retrospectively analyzed. Demographic and clinical data were collected. Respiratory parameters and waveforms during the first 3 days of mechanical ventilation were recorded, with 15-minute waveform segments collected 4 times daily. Airway occlusion pressure (P_0.1) was measured via end-expiratory hold at the end of each recording. IT and DT were identified based on airway pressure, flow, and esophageal pressure waveforms, and the ineffective triggering index (ITI) and DT incidence were calculated. Multivariate Logistic regression was used to identify factors associated with IT and DT. RESULTS: A total of 94 patients with acute brain injury were ultimately enrolled, including 19 cases of traumatic brain injury (20.2%), 39 cases of stroke (41.5%), and 36 cases of post-craniotomy for brain tumor (38.3%). Supratentorial injury was observed in 49 patients (52.1%), while infratentorial injury was identified in 45 patients (47.9%). A total of 94 patients with 1 018 datasets were analyzed; 684 (67.2%) datasets were on pressure support ventilation (PSV), and 334 (32.8%) were on mandatory ventilation. IT was detected in 810 (79.6%) datasets, with a median incidence of 2.1% (0.3%, 12.0%). Datasets demonstrating IT were characterized by lower P_0.1, higher tidal volume (VT), reduced respiratory rate (RR), and decreased minute ventilation (MV) compared to those without IT. The proportion of datasets exhibiting IT was higher during PSV than in mandatory ventilation [83.8% (573/684) vs. 71.0% (237/334), P < 0.05], while, the prevalence of ITI ≥ 10% was lower [23.8% (163/684) vs. 33.5% (112/334), P < 0.05]. DT was detected in 305 datasets (30%), with a median incidence of 0.6% (0.4%, 1.3%). Datasets exhibiting DT were characterized by higher VT, reduced RR, and lower pressure support levels. The incidence of DT was lower in PSV compared to mandatory ventilation modes [0% (0%, 0.3%) vs. 0% (0%, 0.5%), P < 0.05]. The post-craniotomy for brain tumors group exhibited higher ITI, lower RR, reduced MV, and a greater proportion of infratentorial lesions, compared to the TBI group. The infratentorial lesion group demonstrated higher ITI and incidence of DT compared to the supratentorial lesion group [ITI: 3.1% (0.7%, 17.8%) vs. 1.5% (0%, 8.3%), incidence of DT: 0% (0%, 0.5%) vs. 0% (0%, 0%), both P < 0.05]. After adjusting for confounding factors through multivariate logistic regression analysis, infratentorial lesion [odds ratio (OR) = 2.029, 95% confidence interval (95%CI) was 1.465-2.811, P < 0.001], lower P_0.1 (OR = 0.714, 95%CI was 0.616-0.827, P < 0.001), and mandatory ventilation (OR = 1.613, 95%CI was 1.164-2.236, P = 0.004) were independently associated with IT. Additionally, infratentorial lesion (OR = 1.618, 95%CI was 1.213-2.157, P = 0.001), large tidal volume (OR = 1.222, 95%CI was 1.137-1.314, P < 0.001), lower pressure support levels (OR = 0.876, 95%CI was 0.829-0.925, P < 0.001), and mandatory ventilation (OR = 2.750, 95%CI was 1.983-3.814, P < 0.001) were independently associated with DT. CONCLUSION IT and DT were common in patients with acute brain injury. Infratentorial lesions and mandatory ventilation were independently associated with both IT and DT.
Humans ; Respiration, Artificial/methods* ; Retrospective Studies ; Brain Injuries/therapy* ; Intensive Care Units ; Male ; Female ; Middle Aged ; Brain Injuries, Traumatic/therapy* ; Logistic Models ; Aged ; Adult

Bone grafting is a primary method for treating bone defects. Among various graft materials, xenogeneic bone substitutes are widely used in clinical practice due to their abundant sources, convenient processing and storage, and avoidance of secondary surgeries. With the advancement of domestic production and the limitations of imported products, an increasing number of bone filling or grafting substitute materials isentering clinical trials. Relevant experts have drafted this consensus to enhance the management of medical device clinical trials, protect the rights of participants, and ensure the scientific and effective execution of trials. It summarizes clinical experience in aspects, such as design principles, participant inclusion/exclusion criteria, observation periods, efficacy evaluation metrics, safety assessment indicators, and quality control, to provide guidance for professionals in the field.
Humans ; Bone Substitutes/therapeutic use* ; Randomized Controlled Trials as Topic/methods* ; Consensus ; Bone Transplantation ; Research Design

Objective To introduce the application scene,operating steps and preliminary clinical effect of tibial bone mass preservation technique in medial unicompartmental knee arthroplasty(MUKA).Methods A total of 15 patients with antero-medial knee osteoarthritis(AMOA)treated in this hospital from May 2022 to May 2023 were selected as the study subjects.The tibial bone mass preservation technique was a-dopted to complete MUKA(fixed platform prosthesis).The operating time,intraoperative bleeding volume,hospitalization duration and operation complications were recorded.The VAS score before operation and in last follow up,range of motion(ROM)of knee joint,Knee Society Score(KSS),hip and knee stomping angle(HKA)of lower extremity in the operation side and image results were recorded to evaluate the clinical effect.Results The operations in 15 cases were successfully completed.The average operation time was(82.73±9.97)min,mean intraoperative bleeding volume was(21.00±9.49)mL and average hospital stay was(4.9±1.4)d.There was no intraoperative nerve,vascular and medial collateral ligament injury,no iatro-genic fracture,and no postoperative surgical site infection.All patients were followed up for average(5.87±2.77)months.The VAS score of knee joint,ROM,KSS and HKA angle of lower limb in the operated side were significantly improved compared with before operation(P<0.05).There was no prosthesis loosening,displacement or fragmentation,and no obvious degeneration aggravation of the lateral compartment of the knee joint.Conclusion The tibial bone mass preservation technique is a simple,effective and reliable method to deal with the slightly tight flexion space after tibial osteotomy during MUKA,and the postoperative clinical efficacy and imaging results are excellent.

Objective:To investigate the potential utility of the lymphocyte to monocyte ratio (LMR) and its modified index, albumin-LMR product, as predictive biomarkers for disease activity and presence of lupus nephritis in systemic lupus erythematosus (SLE).Methods:A total of 264 patients with newly diagnosed SLE who were treated at Henan Provincial People′s Hospital between December 2016 and September 2022 were included in this study. Their clinical data were subsequently collected for analysis. Patients were classified into non-active disease group (SLEDAI<5, n=55) and active disease group(SLEDAI≥5, n=209) based on the SLE SLEDAI. The Mann-Whitney U test was employed to compare the differences in clinical parameter levels, LMR and albumin-LMR product between the two groups. Additionally, the active disease group was further stratified into mild(SLEDAI 5~9, n=86), moderate(SLEDAI 10~14, n=96) and severe (SLEDAI≥15, n=27) subgroups to assess differences in LMR and albumin-LMR product. Further more patients were stratified into two groups based on renal involvement: those without lupus nephritis(non-LN) and those with lupus nephritis (LN). For non-parametric comparisons, the Mann-Whitney U test was used for intergroup comparisons between two groups, while the Kruskal-Wallis H test was applied for comparisons among three groups. If the Kruskal-Wallis H test revealed statistically significant differences ( P<0.05), pairwise comparisons were performed using the Mann-Whitney U test, and the significance level was adjusted using the Bonferroni method to account for multiple testing.Correlations between LMR, albumin-LMR product, and disease activity indicators were analyzed using Spearman′s correlation. The diagnostic value of LMR and albumin-LMR product for SLE activity was evaluated using the receiver operating characteristic (ROC) curves. Results:Both LMR and albumin-LMR product were significantly lower in active disease group compared to the non-active group {LMR:3.56 (2.15, 5.00) vs. 5.68 (3.89, 7.00); albumin-LMR product [93.21 (59.50, 143.98)g/L] vs. [187.89 (137.67, 260.90)]g/L, Z=-5.68, -7.05, P<0.001 for all}. Further subgroup analysis revealed that LMR and albumin-LMR product levels in severe, moderate, and mild active disease were also significantly decreased compared to the non-active disease group {LMR:3.83(1.78, 5.09)、3.09(2.06, 4.90)、3.65(2.45, 5.03) vs. 5.68(3.89, 7.00); albumin-LMR product: [95.69(66.57, 121.61)]g/L、[79.82(49.02, 126.91)]g/L、[104.73(69.21, 169.01)]g/L vs. [187.89(137.67, 260.90)]g/L, H=34.27, 58.29, P<0.001 for all}. A significant disparity in the levels of LMR and albumin-LMR product was detected between the non-LN and LN, with statistical significance ( Z=-3.44, P=0.001 and Z=-7.06, P<0.001). Correlation analysis indicated that LMR negatively correlated with SLEDAI( r=-0.31), urea( r=-0.29), creatinine ( r=-0.28) and 24-hour urinary protein level ( r=-0.27), all P<0.001, with no significant correlation to complement C3 or C4. Albumin-LMR product showed stronger negative correlations with SLEDAI ( r=-0.44), urea ( r=-0.40), creatinine ( r=-0.37), and 24-hour urinary protein ( r=-0.55), all P<0.001, and a positive correlation with complement C3 ( r=0.18, P=0.004). The areas under the ROC curves for LMR and LMR combined with complement C3 were 0.749 and 0.795, respectively, while for albumin-LMR product and its combination with complement C3, they were 0.809 and 0.833, indicating superior diagnostic efficacy for the modified albumin-LMR product. Conclusion:LMR and albumin-LMR product levels are significantly associated with SLE disease activity and may serve as potential biomarkers for assessing SLE activity and the degree of lupus nephritis.

The paper presents a case of 69-year-old male with marginal zone lymphoma (MZL) manifesting as acute kidney injury (AKI) requiring emergency hemodialysis. The patient presented with fever, fatigue and rapidly progressive renal dysfunction, and serum creatinine was 1 105 μmol/L. Emergency central venous catheterization and hemodialysis were performed. Serum immunofixation electrophoresis revealed monoclonal IgM and λ light chain positivity. Autoantibody testing showed positivity for both anti-SSA and anti-SSB antibodies. Renal biopsy demonstrated interstitial infiltration by atypical B lymphocytes with λ light chain restriction. The diagnosis of MZL was confirmed by bone marrow biopsy. Following hemodialysis and chemotherapy with bendamustine plus rituximab, renal function significantly improved and remained stable during follow-up. This case highlights that AKI may serve as the initial manifestation of lymphoma, underscoring the importance of considering hematologic malignancies in the differential diagnosis of unexplained renal failure.