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1.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
2.
Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献3.
Endometrial receptivity and implantation are important topics in reproductive sciences. No evidence was found to support sperm involvement in endometrial receptivity and its associated factors. This study aimed to explore the effect of the normal human spermatozoa–endometrium cell interaction in regulating genes in the endometrial receptivity pathway. Semen samples were collected from a healthy and fertile man; then, they were incubated with endometrial cells for 24 hr and considered as the sperm group. A group was cultured without spermatozoa and considered as a control group. About 24 hr later, cells were collected from the bottom of the culture dish. The expressions of the VEGF, FGF2, HBEGF, LIFR, EGF, LIF, MUC1, HOXA10, CSF and PGR genes were evaluated in the two groups. Statistical analysis was performed using an independent sample test. Compared with the control group, in the sperm group, the mRNA levels of PGR (p = .0451), VEGF (p = .0101), HBEGF (p = .0163), EFG (p = .0339), FGF2 (p = .012), LIF (p = .0324), LIFR (p = .0321) and HOXA10 (p = .0098) were significantly upregulated. The results showed that there is a need for the interaction between spermatozoa and endometrium for implantation and can be used for preparing uterine in in vitro fertilisation cycles. 相似文献
4.
Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer. 相似文献
5.
Maryam Noroozian Sina Ghasemi Seyed-Mohammad-Reza Hosseini Amirhossein Modabbernia Mohammad-Reza Khodaie-Ardakani Omid Mirshafiee Mehdi Farokhnia Masih Tajdini Farzin Rezaei Bahman Salehi Mandana Ashrafi Habibeh Yekehtaz Mina Tabrizi Shahin Akhondzadeh 《Psychopharmacology》2013,228(4):595-602
Rational
A growing body of evidence illustrates that 5-HT3 receptor antagonist drugs may be of benefit in the treatment of negative symptoms in schizophrenia.Objective
The objective of this study was to assess the efficacy and tolerability of tropisetron add-on to risperidone on negative symptoms in patients with chronic stable schizophrenia.Methods
In a double-blind, placebo-controlled 8-week trial, 40 patients with chronic schizophrenia who were stabilized on risperidone were randomized into tropisetron or placebo add-on groups. Psychotic symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) every 2 weeks. Furthermore, extrapyramidal and depressive symptoms as well as side effects were assessed. The primary outcome measure was the difference in change from baseline of negative subscale scores between the two groups at week 8.Results
Tropisetron resulted in greater improvement of the total PANSS scores [F(1.860,70.699)?=?37.366, p?<?0.001] as well as negative scores [F(2.439,92.675)?=?16.623, p?<?0.001] and general psychopathology [F(1.767,67.158)?=?4.602, p?=?0.017], but not positive subscale scores [F(1.348, 51.218)?=?0.048, p?=?0.893] compared to placebo. In a multiple regression analysis controlling for positive, extrapyramidal, and depressive symptoms, treatment group (standardized β?=??0.640) significantly predicted changes in primary negative symptoms. The side effect profile did not differ significantly between the two groups.Conclusion
Tropisetron add-on to risperidone improves the primary negative symptoms of patients with chronic stable schizophrenia. 相似文献6.
7.
Adamantinoma is a primary low grade malignant bone tumor that is predominantly located in the mid-portion of the tibia. The tumor is of interest for two reasons: first, there still exists considerable dispute as to the origin of the lesion and recent reports reveal that the condition is more malignant than had previously been supposed. Although cases of adamantinoma located to the axial skeleton have been reported, this is the first case of adamantinoma located to pelvic bone in Iran. Here we present the clinical, radiological & histopathological features of a 19 year-old male with painful lesion located to the right pelvic bone which was morphologically and immunohistochemically diagnosed as adamantinoma. In general, metastasis is seen in 15%–20% of patients. The spread can occur to regional nodes, lung and infrequently to skeleton, liver and brain. Several weeks after surgery, our patient’s condition gradually worsened. A CT-scan of abdomen revealed widespread liver metastasis and the patient died due to acute liver failure. This case demonstrates that the mortality rate from adamantinoma is not always low. 相似文献
8.
Masoud Mohammad Andalib Masoud Mohammad Malekzadeh Zahra Agharahimi Maede Daryabeigi Bahareh Yaghmaei Mahmoud-Reza Ashrafi Ali Rabbani Nima Rezaei 《Iranian journal of pediatrics.》2015,25(5)
Background:
Tertiary pediatric hospitals usually provide excellent clinical services, but such centers have a lot to do for educational perfection.Objectives:
This study was performed to address under-graduate educational deficits and find feasible solutions.Patients and Methods:
This cross-sectional study was done in a target population of 77 sixth year undergraduate medical students (response rate = 78%) who spent their 3-month pediatric rotation in the Children’s Medical Center, the Pediatrics Center of Excellence in Tehran, Iran. The Dundee ready educational environment measure (DREEM) instrument was used for assessing educational environment of this subspecialized pediatric hospital.Results:
Among 60 students who answered the questionnaires, 24 were male (40%). Participants’ age ranged from 23 to 24 years. The mean total score was 95.8 (48%). Comparison of scores based on students’ knowledge showed no significant difference. Problematic areas were learning, academic self-perception, and social self-perception.Conclusions:
Having an accurate schedule to train general practitioner, using new teaching methods, and providing a non-stressful atmosphere were suggested solutions. 相似文献9.
10.