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101.
Normal spermatogenesis results from a balance between process of cell proliferation, cell differentiation and apoptosis that concern somatic cells and germ cells. Dysfunction of spermatogenesis may be the result of constitutional or acquired abnormalities of spermatogonia stem cells or somatic cells. To overcome these problems, it seems necessary to implement preventive measures for germ stem cell preservation or substitute measures to replace them, the objective being to replicate in vivo or in vitro the process of spermatozoa production. This article will discuss the different experimental strategies for considering the in vivo or in vitro production of spermatozoa, outside the physiological process.  相似文献   
102.
The three broodCeriodaphnia dubia test was carried out on fifteen formulations and pure compounds presently in general use in a variety of treatment processes or as reference toxicants. The most toxic substances (LC50 (based on survival/EC50 (based on total progeny) <10 mg/L) were metallic Cu, tertiary dodecyl mercaptan, an antioxidant TIA-RCO T-424, Cu(NO3)2 · 3H2O, K2Cr2O7, NALCO 7139-a flocculent, DOWFAX 2EP-a surfactant, TB-66-an algicide and ammonia. Exposure to these compounds elicited the same response fromC. dubia for the two endpoints examined-survival and reproductive success. Two antimicrobials, PROXEL GXL and DOWICIL 75, and the surfactant sodium lauryl sulfate, were slightly toxic (LC50/EC50<100 mg/L) for both endpoints studied. Two coagulants, NALCO 7109 and NALCO 8120 and a flocculent PERCOL 757 were practically nontoxic (LC50>100 mg/L) to slightly toxic (LC50<100 mg/L) when the survival endpoint was examined, but were moderately toxic (EC50<10 mg/L) to slightly toxic (EC50<100 mg/L) when the endpoint of reproductive success was examined. These formulations and pure compounds had generally a declining effect on mean brood size, though there were exceptions to this observation as the broods progressed in number.  相似文献   
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In a pilot double-blind, randomized, prospective controlled study the effectiveness and safety of 0.3% netilmicin ophthalmic solution were compared with those of 0.3% tobramycin in treating external bacterial ocular infections in 45 eligible patients. The treatment with both study medications resulted in a significant (p < 0.001, Wilcoxon test) reduction in the mean cumulative score of the signs and symptoms. However, no statistically significant differences were observed between the two groups. The clinical improvement rate was almost complete with either antibiotics. There was a statistically positive trend in the netilmicin group with regard to the microbiological improvement that was achieved in (87% of the netilmicin patients) compared with 77% of the tobramycin patients (77%). Antibiotic sensitivity revealed that 84% of the organisms isolated were sensitive to netilmicin whereas only 64% of them were sensitive to tobramycin. Only minor adverse events occurred in patients treated with either netilmicin or tobramycin. In conclusion, this study demonstrates that netilmicin is a promising new antibiotic for treating external ocular infections.  相似文献   
106.
The effect of spironolactone on the urinary excretion of prostaglandins was studied in patients with liver cirrhosis and ascites. Patients were kept in bed and given a sodium-restricted diet for at least 4 days before spironolactone treatment was considered. Starting from the 5th day of protocol, patients were treated with this diuretic if their spontaneous weight loss had been less than 600 g during the 2 previous days. Patients were distributed in groups according to weight loss during the first 4 days on diuretic therapy: Group I (high responders), II (medium responders) and III (low responders). Group I patients showed higher basal values (4th day of protocol) of urinary sodium (P less than 0.02) and urinary 6-keto-PGF1 alpha (P less than 0.02) than the other patients, but there were no significant differences in the basal excretion rates of PGE2 nor TXB2 among the groups. The therapeutic requirement for spironolactone treatment in patients from Group I was delayed as compared with the other two groups (P less than 0.001) due to the fact that their spontaneous weight loss took place over a long period. For all patients, spironolactone administration produced a significant increase in 6-keto-PGF1 alpha excretion (P less than 0.01) without affecting significantly urinary elimination of PGE2 nor TXB2. A close relationship was found between the spironolactone-induced increments in urinary sodium and urinary 6-keto-PGF1 alpha excretion (r = 0.74, P less than 0.001). It is suggested that the ability of the kidney to synthetize prostacyclin can influence the natriuretic response to spironolactone therapy in patients with liver cirrhosis.  相似文献   
107.

Purpose of Review

The aim of this review is to find out the benefits of retroperitoneoscopy for the most common urological diseases in children.

Recent Findings

The emergence of minimally invasive surgery about 20 years ago revolutionized pediatric urology. In this context, laparoscopy and later retroperitoneoscopy were developed and applied to a wide spectrum of urological diseases. Both approaches have since presented benefits and disadvantages that have been documented in various series. The main indications of retroperitoneoscopy are presented, from the classical ablative surgery, like total or partial nephrectomy, to more advanced reconstructive surgery. The success rate is similar to open surgery. However, few comparative studies have been conducted.

Summary

According to the most recent findings, retroperitoneoscopic surgery in children is feasible and safe if performed by well-trained surgeons. A pediatric urologist would favor the retroperitoneoscopic access to reach the upper urinary tract and the kidney because this is the “natural” way to treat the most common urological pediatric diseases.
  相似文献   
108.
BACKGROUND: The model for end-stage liver disease (MELD) score is a useful tool to assess prognosis in critically ill cirrhotic patients. However, its short-term prognostic superiority over the traditional Child-Turcotte-Pugh (CTP) score has not been definitely confirmed. The creatinine serum level is an important predictor of survival in patients with liver cirrhosis. AIMS: To evaluate and compare the short-term prognostic accuracy of the CTP, the creatinine-modified CTP, and the MELD scores in patients with liver cirrhosis. METHODS: CTP, creatinine-modified CTP, and MELD scores were calculated in a cohort of 145 cirrhotic patients. The creatinine-modified CTP was calculated as follows: we assessed the mean creatinine serum level and standard deviation (SD) of the 145 study patients, then assigned a score of 1 to patients with creatinine serum levels < or = to the mean, a score of 2 to patients with creatinine levels between the mean and the mean+1 SD, and a score of 3 to patients with creatinine levels above the mean+1 SD. The creatinine-modified CTP was then calculated by simply adding each patients' creatinine score to their traditional CTP scores. We calculated and compared the accuracy (c-index) of the three parameters in predicting 3-month survival. RESULTS: The creatinine-modified CTP score showed better prognostic accuracy as compared with the traditional CTP (P=0.049). However, the MELD score proved to be better at defining patients' prognosis in the short-term as compared with both the traditional CTP score (P=0.012) and the creatinine-modified CTP (P=0.047). The excellent short-term prognostic accuracy of the MELD score was confirmed even when patients with abnormal creatinine serum levels were excluded from the analysis (c-index=0.935). CONCLUSIONS: Adding creatinine values to the CTP slightly improves the prognostic usefulness of the traditional CTP score alone. The MELD score has a short-term prognostic yield that is better than what is provided by both the CTP and CTP creatinine-modified scores, even in cirrhotic patients who are not critically ill. The positive results obtained by using the MELD score were confirmed even after excluding patients with impaired renal function.  相似文献   
109.
In B-cell chronic lymphocytic leukemia (CLL), accumulation of neoplastic B cells may be the result of dysregulated apoptosis. One of the major molecules triggering apoptosis, CD95 (FAS), is not expressed on CLL B cells at resting conditions. However, CD40 triggering of CLL B cells upregulates receptors belonging to the tumor necrosis factor (TNF) superfamily, like CD95. In the present study, we analyzed in B cells from 20 CLL patients the effect of CD40/CD40L interaction on: (i) CD95 modulation; (ii) CD95-mediated apoptosis and (iii) mRNA and protein expression of the death-inducing signaling complex (DISC) molecules.CD40 activation of CLL B cells was carried out by coculture with CD40L-transfected cells and cytofluorimetric analyses were performed to study CD95 modulation and apoptosis induction by an anti-CD95 moAb. Despite strong CD95 upregulation on the membrane of all the cases studied, only a minority of cases analyzed (3/20) proved weakly responsive to CD95-mediated apoptosis. Multiplex RT-PCR was used to analyze FLICE, FAS, FADD and TRADD mRNAs before and after CD40 triggering. In agreement with the cytofluorimetric data, FAS mRNA appeared significantly increased after CD40 triggering; the other molecules involved in DISC formation and in CD95-mediated apoptosis were also expressed without relevant differences between resting and activated conditions. Western blot analyses further confirmed FLICE and FADD protein expression by resting and activated CLL cells. Our findings demonstrate that, following CD40 triggering, CLL B cells are resistant to CD95-mediated apoptosis despite a strong CD95 upregulation on the membrane and a normal mRNA or protein expression of the DISC components.  相似文献   
110.
To examine the effects of dobutamine on pulsed-Doppler left ventricular filling indices and its utility for evaluation of CAD we studied 14 patients with normal coronary arteries (Group 1) and 39 patients with significant CAD (>70% diameter stenosis). Patients with coronary artery disease (CAD) were divided into two groups: patients with one-vessel coronary disease (Group 2); and those with multivessel CAD (Group 3). After stopping cardioactive treatment, patients underwent incremental dobutamine stress (5, 10, 20, 30 and 40 microg/kg/min) during pulsed-Doppler interrogation of diastolic filling with simultaneous heart rate and blood pressure measurements. The following transmitral Doppler variables were measured at baseline and at peak-dose of dobutamine: peak early (E) and peak atrial (A) velocity; E/A ratio; acceleration time (AT) and deceleration time (DT) of E wave; isovolumic relaxation time (IVRT); and time-velocity integral (TVI). Two-dimensional echocardiography was performed to detect regional asinergy and analyzed using a 16 segment model. RESULTS: Normals and CAD patients showed comparable changes in heart rate and blood pressure (P=NS between groups). Intergroup analysis of the changes of transmitral flow showed the significant changes for these indices (P<0.001): E velocity (-2.78+/-10.04, 12.4+/-9.4 and 16.47+/-10.65 cm/s); AT of E wave (1.66+/-2.47, -5.2+/-1.38 and -4.66+/-2.39 m/s(2)); DT of E wave (-0.23+/-0.18, 0.2+/-0.2 and 0.2+/-0.28 m/s(2)); and TVI of transmitral flow (-1.26+/-0.7, 3.5+/-1.75 and 4.1+/-1.66 cm), respectively for Groups 1, 2 and 3. All other transmitral Doppler variables showed insignificant changes (P=NS) to dobutamine between groups. It is important that the significance of these changes were the same for patients with one-vessel and those with multivessel coronary disease. In conclusion, during dobutamine stress testing, patients with CAD, had an abnormal response of these transmitral Doppler indices: E wave; AT of E wave; DT of E wave; and the TVI of transmitral flow. The abnormal responses of these Doppler indices of left ventricular filling are more accurate markers of significant single vessel CAD than new wall motion abnormalities during conventional DSE.  相似文献   
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