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1.
The influence of co-solvents on the in-vitro percutaneous penetration of indomethacin from gel systems was studied using a simplex lattice experimental design. Gel formulations were prepared by gelling the vehicle mixture of water, either alcohol or isopropanol and either propylene glycol or PEG 400 with 1% w/w Carbomer 940. Hairless mouse skin was employed as the barrier in a Franz-type diffusion cell. The penetration rates at steady state for seven formulations were fitted to a polynomial equation based on this simple lattice method and a three-dimensional plot was constructed. The formulation having the maximal penetration rate was determined to be the vehicle with a solvent ratio of water: alcohol: propylene glycol equal to 15:33:52, and which possessed a solubility parameter of 15 and a drug solubility of around 10 mg mL?1. When the solubility parameter of the vehicle was > 15, the drug solubility increased. However, the penetration rate decreased with an increasing solubility parameter. For those vehicles with a solubility parameter < 15, both the drug solubility and the penetration rate decreased with a decrease in the solubility parameter. There was shown to be an approximately 20-fold increase in the relative enhancement factor when using both alcohol and isopropanol, but only a threefold increase for both propylene glycol and PEG 400, when compared with water.  相似文献   
2.
Ten stations alongside major thoroughfares were selected as exposure sites, while a small village located about 3 kilometers away from a main traffic route was selected as the control site. The concentrations of particulate matters with aerodynamic less than 2.5 μm (PM2.5) and elemental carbon (EC) at exposure sites were both higher than those at the control site. Daytime mean concentrations of total polycyclic aromatic hydrocarbons (t-PAHs), carcinogenic PAHs (car-PAHs), and Benzo(a)pyrene-equivalent dose (BaPeq) at exposure sites were all about twice as high as those at the control site. A significant relationship between t-PAHs and EC was found, suggesting that most of the t-PAHs at exposure sites were contributed by diesel exhaust. Furthermore, the diagnostic ratios also show that diesel emissions were the dominant sources of PAHs at exposure sites. A multiple linear regression was applied to urinary 1-hydroxyprene (1-OHP) using four variables (exposure status, sex, smoker status, and incense burning) as independent variables. The results showed that the concentrations of 1-OHP in exposure groups were significantly (p < 0.001) higher than those in the control group. The explainable percentage for exposure status was 91.1%, indicating that the exposure factor, in comparison with other factors, has a dominant contribution to the concentration of 1-OHP. After subtracting the background levels of 1-OHP, the levels of urinary 1-OHP for residents exposed to the exhaust of 100 vehicles were about 0.062 μg/g creatinine.  相似文献   
3.
Routine Blastocyst Culture and Transfer: 201 Patients' Experience   总被引:4,自引:0,他引:4  
Purpose: The purpose was to compare the outcomes betweenday-5 blastocyst and day-2 embryo transfers. Methods: Infertile women who accepted the ovarian hyperstimulationand oocyte retrieval were divided: Group 1, day2 embryo transfer, group 2, cultured to day 5 in serum-freesequential culture medium and transfer. Early embryoquality and growth, blastocyst formation and quality,implantation rate (IR) and pregnancy rates (PR) weredetected. Results: Total blastocyst formation rate was 49.4%. Betterearly embryo quality (days 2, 3) and higher day 3 blastomerenumber possess higher blastocyst formation rate. The IR forday 2 and day 5 embryos were 10.8% and 22.2%, respectively.The PR in both groups were comparable (37.3% vs. 41.8%). Conclusions: Blastocyst transfer has higher IR and comparablePR as those of day 2 embryo transfer. Early embryoqualities and day 3 blastomere number are useful in predictingthe final blastocyst formation. Blastocyst formationrate is not related to maternal age, infertile causes, inseminationmethods, and early embryo number.  相似文献   
4.
BACKGROUND: We examined the external genitalia of 2149 elementary schoolboys in the suburban area of Taichung in Taiwan for an understanding of foreskin development before adolescence. METHODS: The study's subjects comprised 692 first-grade boys, 725 fourth-grade boys, and 732 seventh-grade boys. The foreskin's condition was classified as: type I (normal prepuce), type II (adhesion of prepuce), type III (partial phimosis), type IV (phimosis) and type V (circumcised foreskin). Other abnormalities of the genitalia also were recorded. All of the examinations were performed by the same urologist. RESULTS: The incidence of type I foreskin was 8.2% in first-grade boys, 21.0% in fourth-grade boys, and 58.1% in seventh-grade boys. The incidence of type IV foreskin was 17.1% in first-grade boys, 9.7% in fourth-grade boys, and 1.2% in seventh-grade boys. Only one boy had balanoposthitis. Other abnormalities included inguinal hernia (n = 2), hydrocele (n = 12), cryptorchitism (n = 8), varicocele (n = 22), and subcoronal-type hypospadia (n = 1). CONCLUSIONS: Physiological phimosis declines with age. Most boys with phimosis in this study did not require treatment.  相似文献   
5.
The relationship between the prognosis and age of patients with gastric cancer is controversial. To evaluate whether there is a biological characteristic specific to the age of patients, we examined the clinical characteristics of patients with gastric cancer with special reference to their age. Based on a prospective database, a retrospective study of 419 patients who underwent radical gastrectomy for cure in the past 6 years was conducted. Clinical characteristics including gender, gross appearance of the tumour (Borrmann's classification, tumour location), histopathology (depth of tumour invasion, lymph node status, Lauren's classification and degree of tumour cell differentiation) and TNM tumour stage were analysed in six different age groups (< 39, 40–49, 50–59, 60–69, 70–79, > 80 years). The mean age of the 419 patients was 64.6 years (range from 26–91) and the peak age incidence of gastric cancer (46.3%) was in the 60–69 year old age group. The male: female ratio was 4.6: 1 on the whole and male gender predominated at ages > 60. The proportion of diffuse type tumours (68.4%) by Lauren's criteria in the young age group (< 39 yrs) decreased with age (25% in the > 80 years group; P<0.001). Similarly, the proportion of poorly-differentiated tumours (89.5%) in the young age group (< 39 yrs) decreased with advancing age (P<0.001). These findings suggest that both diffuse type and poorly-differentiated tumours predominate in younger patients and, without considering the factor of delay in diagnosis, may explain the poorer prognosis demonstrated in younger patients.  相似文献   
6.
7.
Background: It has been proposed that the volatile anesthetic isoflurane induces neuroprotection and that the endogenous opioid peptide dynorphin induces neurocytotoxicity in cells. The levels of dynorphin are often significantly elevated in neuropathophysiological conditions, and dynorphin can directly induce toxicity. However, the neuroprotective effects of isoflurane on dynorphin-induced cytotoxicity are still unclear.
Methods: In order to determine the effect of isoflurane on dynorphin-induced cytotoxicity in neuronal cells, we have designed a device wherein cultured human neuroblastoma SH-SY5Y cells can be exposed to isoflurane. Fully differentiated SH-SY5Y cells were obtained by treating the cells with retinoic acid for 6 days. We examined SH-SY5Y cell survival, apoptosis, and antiapoptotic protein expression by cell viability, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling stain, and Western blot analysis, respectively.
Results: After 16 h of dynorphin (10 μM) treatment, the SH-SY5Y cells showed significant cytotoxicity, apoptosis, and downregulation of the antiapoptotic Bcl-2 protein expression. These effects of dynorphin were significantly inhibited by isoflurane exposure for 32 h [pretreatment for 16 h and posttreatment (after dynorphin treatment) for 16 h].
Conclusion: Thus, our results suggest that isoflurane exerts neuroprotective effects in the case of dynorphin-induced pathophysiological disruption.  相似文献   
8.
Bladder tamponade is an uncommon clinical symptom among men who experience suffering related to sexual intercourse. The authors report on a 46-year-old man with this symptom 4-5 years before hospitalization. Angiography confirmed the presence of left pudendal and obturator arterial bleeding, and embolotherapy of the internal pudendal and obturator arteries was performed. There was no mortality, or limb loss or loss of sexual potency at follow-up.  相似文献   
9.
Abstract Pre-operative serum tissue polypeptide antigen (TPA) levels were measured in cases of gastric cancer from December 1987 to December 1992. All 351 cases received gastrectomies. The clinicopathological factors were analysed. The significant factors that correlated with the elevation of pre-operative serum TPA levels included tumour size (> 7 cm), Borrmann-type cancers, late stages (III and IV), lymph node metastasis, hepatic metastasis and Ming's expanding type cancers. Multivariate analysis showed that the tumour size (> 7 cm) and the presence of hepatic metastasis are significant factors. To clarify the relationships between gastric cancer per se and the pre-operative serum TPA levels, we selected cases without evidence of metastasis (n = 139). The tumour size was the only significant factor when multivariate analysis was applied. Possibilities of hepatic recurrence were found in cases with high pre-operative serum TPA levels (> 220 U/L), even radical gastrectomies were performed. A high pre-operative serum TPA level did not display a poor survival prognosis, if the radical gastrectomy was possible. We thus concluded that: (i) elevated pre-operative serum levels of TPA are associated with either a large size tumour (> 7 cm) or the presence of hepatic metastasis and the tumour size is the most important factor relating to the serum TPA levels; (ii) high pre-operative serum TPA levels (> 220 U/L) may serve as indicators of later hepatic recurrence; and (iii) elevated serum TPA levels were not indicators of survival prognosis.  相似文献   
10.
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