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121.
Primary renal lymphoma and xanthogranulomatous pyelonephritis in childhood   总被引:3,自引:0,他引:3  
Primary renal non-Hodgkin's lymphoma is very rare in childhood. A six-year-old boy presented with bilateral non-obstructive multinodular nephromegaly and renal failure. Percutaneous needle biopsy showed large-cell lymphoma. The patient was started on chemotherapy. A right nephrectomy was done when systemic hypertension developed in the presence of a non-functional right kidney. Histopathologic examination revealed focal lymphomatous infiltration and xanthogranulomatous pyelonephritis which is an atypical form of chronic renal infection. The case is discussed in relation to previons reports.  相似文献   
122.
The present study was undertaken to determine the precise location of the mental and mandibular foramina and the surrounding anatomic landmarks. Measurements were made on both right and left sides of each of 34 dried young Turkish adult (30-40 years old) human male mandibles. The mandibles were moderately robust and were from dentulous subjects. The results obtained in the study showed that the distance of the mandibular foramen to the angle of the anterior ramus were 16.9 mm on the right and 16.78 mm on the left. The distance to the posterior side of the ramus was 14.09 mm on the right, and 14.37 mm on the left. The narrowest anteroposterior diameters were 32.8 mm on the right and 32.05 mm on the left. The mandibular foramen is 0.5 mm posterior to the centre of the ramus on the right and 0.75 mm on the left. The distance of the lowest point of mandibular notch to the foramen was 22.37 mm on the right and 22.17 mm on the left. The distance from the mandibular foramen to the inferior border of the ramus in the mid position of the ramus was 30.97 mm on the right and 29.75 mm on the left. The average angle of the mandible (gonial angle) was 120.17 degrees on both sides. The distance of the mental foramen to the inferior border of the mandible was 14.61 mm and 14.29 mm on the right and left, respectively. Its distance to the superior border was 13.62 mm on the right and 14.62 mm on the left. The horizontal dimensions of the mental foramen was 2.93 mm on the right, 3.14 mm on the left and its vertical dimension was 2.38 mm on the right and 2.64 mm on the left. The mental foramen was located below the root of the second premolar in 21 bones (61.76%) on the right and 17 bones (50%) on the left while in the remaining mandibles, the foramen was present between the roots of the first and second premolars in 13 bones (38.2%) on the right and in 17 (50%) on the left. The average angle of the mental foramen was 96.82 degrees.  相似文献   
123.
The acute effects of 50 mg of sildenafil on tear functions were evaluated in 12 impotent patients. Mean tear breakup time, cotton thread, and Schirmer I tests were 19.42±6.45 s, 13.92±6.63 mm, and 16.58±12.19 mm, respectively before sildenafil and 20.33±10.40 s, 10.92±6.14 mm, and 18.08±12.36 mm, respectively, 1 hour after sildenafil. The results suggest that sildenafil does not adversely affect tear functions. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
124.
Left Ventricular Diastolic Functions in Juvenile Rheumatoid Arthritis   总被引:1,自引:0,他引:1  
Cardiac involvement as pericarditis, myocarditis, and endocarditis is common in juvenile rheumatoid arthritis (JRA). Though there are many reports concerning systolic and diastolic functions of adults with rheumatoid arthritis, there are no studies on children with JRA. Thirty patients with JRA without any cardiac symptoms and 30 sex- and age-matched controls were included in the study. M-mode and pulsed-wave Doppler echocardiography were performed on each participant to assess the systolic and diastolic functions of the left ventricle. Left ventricular end-systolic diameter and volume were larger and ejection fraction and fractional shortening were decreased in the JRA group. Among the diastolic parameters, increased late flow velocity, decreased early flow velocity, and prolonged isovolumic relaxation time reflected an abnormal relaxation form of diastolic dysfunction. Mortality rate is increased in adults with rheumatoid arthritis, and ischemic heart disease is the leading cause of cardiovascular mortality. The abnormal relaxation form of diastolic dysfunction found in children with JRA is seen in ischemic heart disease. These children can therefore be candidates for ischemic heart disease in the future even though they are fully asymptomatic at present. In conclusion, children with JRA should be assessed for systolic and diastolic functions with serial echocardiography. In this way it may be possible to reduce the mortality and morbidity of the disease from cardiac causes.  相似文献   
125.
Carcinogenic tobacco-specific nitrosamines are present in tobacco products and are believed to play a significant role in human cancers associated with tobacco use. Additional amounts of tobacco-specific nitrosamines could be formed endogenously. We tested this hypothesis by treating rats with nicotine and sodium nitrite and analyzing their urine. Initially, we treated groups of rats with (S)-nicotine (60 micromol/kg) and NaNO2 (180 micromol/kg), (S)-nicotine alone, NaNO2 alone or 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 12 nmol/kg) by gavage twice daily for 4 days. We collected urine and analyzed for two metabolites of NNK; 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanol and its glucuronide. We did not detect these metabolites in the urine of rats treated with nicotine alone or nicotine plus NaNO2, indicating that endogenous conversion of nicotine to NNK did not occur. However, the urine did contain N'- nitrosonornicotine (NNN), N'-nitrosoanabasine (NAB) and N'- nitrosoanatabine (NAT). Analysis of the (S)-nicotine used in this experiment demonstrated that it contained trace amounts of nornicotine, anabasine and anatabine. In a second experiment, we used an identical protocol to compare the endogenous nitrosation of this (S)-nicotine with that of synthetic (R,S)-nicotine, which did not contain detectable amounts of nornicotine, anabasine or anatabine. NNN (0.53 x 10(-3)% of nicotine dose), NAB (0.68%) and NAT (2.1%) were detected in the urine of the rats treated with the (S)-nicotine and NaNO2. NNN (0.47 x 10(- 3)% of dose), but not NAB or NAT, was present in the urine of the rats treated with synthetic (R,S)-nicotine and NaNO2. NNN probably formed via nitrosation of metabolically formed nornicotine. These results demonstrate for the first time that endogenous formation of tobacco- specific nitrosamines occurs in rats treated with tobacco alkaloids and NaNO2. The potential significance of the results with respect to nitrosamine formation in people who use tobacco products or nicotine replacement therapy is discussed.   相似文献   
126.
The present study investigated the expression and distribution of three isoforms of nitric oxide synthase (NOS) in different anatomical regions of the human stomach and in gastric neoplastic tissues by immunohistochemistry using specific antibodies. Intracellular localization of individual isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer tissues had a marked reduction of all three NOS isoforms expression. The expression of the endothelial NOS, neuronal NOS and inducible NOS in the tumor tissue was significantly lower than in normal gastric mucosa (P = 0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the expression of inducible NOS was significantly lower than the expression of both constitutive forms of NOS (P < 0.01). There was a tendency to higher expression of both constitutive forms of NOS in earlier stages T2 of the tumor compared to advanced T4 tumor. In contrast, the expression of inducible NOS was higher than in the advanced T4 tumor than in the earlier stages T2 of the tumor. The mapping of the expression of endothelial NOS, neuronal NOS and inducible NOS in human stomach showed higher expression of NOS isoforms in the distal third than in the proximal third of the stomach (P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is greater expression of NOS in the stomach corpus and in antrum than in the proximal third of the normal human stomach mirroring the anatomical predilection of common pathological changes in this part of the human stomach. Furthermore, there was loss of the expression of individual isoenzymes in gastric neoplasms.   相似文献   
127.
Hecht  SS; Spratt  TE; Trushin  N 《Carcinogenesis》1997,18(9):1851-1854
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)- (+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown that the enantiomeric ratio of metabolically formed NNAL and its glucuronide derivative may be species dependent. However, the absolute configuration of such NNAL has not been previously reported. Synthetically prepared racemic NNAL was converted to diastereomeric esters by reaction with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha- (trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and the products were characterized by 1H-NMR. Based on chemical shift data, the absolute configuration of NNAL in each diastereomeric ester was assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the absolute configurations of the diastereomeric carbamates formed by reaction of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of metabolically produced NNAL to the same carbamates allowed us to assign the NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and minor NNAL-glucuronide diastereomers found in the urine of patas monkeys and humans exposed to NNK were similarly assigned; they were formed from (R)-NNAL and (S)- NNAL, respectively.   相似文献   
128.
129.
130.

Research question

Are high-responder IVF patients protected from the deleterious effect of prematurely elevated serum progesterone level on the probability of pregnancy?

Design

In this retrospective cohort study, 2971 autologous fresh embryo transfer IVF cycles with gonadotrophin-releasing hormone agonist long protocol were analysed to investigate whether the detrimental effect of prematurely rising progesterone levels on clinical pregnancy rate (CPR) varies depending on the magnitude of ovarian response. Nine different evenly spaced intervals were constructed for serum progesterone level on the human chorionic gonadotrophin day (<0.5/0.5–0.9/1–1.4/1.5–1.9/2–2.4/2.5–2.9/3–3.4/3.5–3.9/>4 ng/ml). Then, IVF cycles in each of these intervals were further divided into low (≤3 oocytes), normal (4–15 oocytes) and high responders (≥16 oocytes).

Results

The progressive rise of serum progesterone from the <0.5 to the >4 ng/ml interval caused a gradual and continuous decline in the CPR of all three types of ovarian response. The absolute difference in the CPR between the lowest and the highest progesterone groups was not related to the magnitude of ovarian response (–26.6%, –37.7% and –40.7% for the low, normal and high responders, respectively). On multivariate logistic regression analysis, the detrimental effect of progesterone started at 1.5–1.9 ng/ml, 3.0–3.4 ng/ml and 4.0–4.4 ng/ml intervals for the low, normal and high responders, respectively.

Conclusion

High responders are not exempt from the detrimental effects of prematurely rising serum progesterone levels but the threshold interval where the detrimental effect begins is higher in the high responders compared with the low and normal responders.  相似文献   
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