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41.
42.
The laryngeal mask airway (LMA) was introduced for clinical use in 1988. It represents a new concept in airway management. Its role has been described as filling the gap between tracheal intubation and the anesthesia face mask. It is inserted without direct visualization into the hypopharynx and when properly positioned forms a low pressure seal around the laryngeal inlet, allowing spontaneous as well as gentle positive pressure ventilation. Since its introduction, its indications and applications in anesthesia practice have increased. Although initially used as a means of delivering anesthesia and obviating the need for holding a mask on the patient, its position directly over the laryngeal inlet makes it a useful guide during flexible bronchoscopy. We report our experience in six pediatric patients and describe an anesthetic technique for bronchoscopy using the LMA for general anesthesia with spontaneous ventilation. Pediatr Pulmonol. 1996; 21:57–61. © 1996 Wiley-Liss, Inc.  相似文献   
43.
We are interested in studying the possibility of modulating prostatic cell growth by manipulating apoptosis. Here we show that 1 μM staurosporine (STS) induces a human androgen-independent prostatic tumor cell line, DU145, to undergo dramatic changes in morphology and results in programmed cell death. Several genes involved in apoptosis were analyzed for expression in STS-treated and untreated DU145 cells. It was observed that these genes were differentially regulated. The expression level of bcl-2, bcl-xL, Ich-1L remains unchanged in treated and untreated cells. On the other hand, DAD1 and interleukin-1β-converting enzyme (ICE) were downregulated while bcl-xs and Ich-1s were upregulated. By blocking bcl-2 gene expression using antisense oligonucleotides, it was determined that the anti-bcl-2 oligonucleotides have no effect on the proliferation of DU145 or STS-treated DU145 cells. These results demonstrate that programmed cell death can be induced in an androgen-independent prostatic cancer cell line and BCL-2 was found not to play an important role in preventing STS-induced apoptosis in the DU145 cell line. © 1996 Wiley-Liss, Inc.  相似文献   
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45.
Estrogens exert pleiotropic effects on multiple physiological and behavioral responses. Male and female sexual behavior in rodents constitutes some of the best‐characterized responses activated by estrogens in adulthood and largely depend on ERα. Evidence exists that nucleus‐ and membrane‐initiated estrogen signaling cooperate to orchestrate the activation of these behaviors both in short‐ and long‐term. However, questions remain regarding the mechanism(s) and receptor(s) involved in the early brain programming during development to organize the circuits underlying sexually differentiated responses. Taking advantage of a mouse model harboring a mutation of the ERα palmitoylation site, which prevents membrane ERα signaling (mERα; ERα‐C451A), this study investigated the role of mERα on the expression of male and female sexual behavior and neuronal populations that differ between sexes. The results revealed no genotype effect on the expression of female sexual behavior, while male sexual behavior was significantly reduced, but not abolished, in males homozygous for the mutation. Similarly, the number of kisspeptin‐ (Kp‐ir) and calbindin‐immunoreactive (Cb‐ir) neurons in the anteroventral periventricular nucleus (AVPv) and the sexually dimorphic nucleus of the preoptic area (SDN‐POA), respectively, were not different between genotypes in females. In contrast, homozygous males showed increased numbers of Kp‐ir and decreased numbers of Cb‐ir neurons compared to wild‐types, thus leading to an intermediate phenotype between females and wild‐type males. Importantly, females neonatally treated with estrogens exhibited the same neurochemical phenotype as their corresponding genotype among males. Together, these data provide evidence that mERα is involved in the perinatal programming of the male brain.  相似文献   
46.
To identify new candidate anticancer compounds, we here report the synthesis of benzimidazole derivatives: diethyl 2,2′-(2-oxo-1H-benzo[d]imidazole-1,3(2H)-diyl) diacetate and its arylideneacetohydrazide derivatives, using ultrasonic irradiation and conventional heating. The compounds were confirmed by Nuclear magnetic resonance (NMR) (JEOL, Tokyo, Japan) and Fourier transform infrared spectroscopy (FTIR) spectroscopy (Thermoscientific, Waltham, MA, USA). The molecular structure and electronic properties of the studied compounds were predicted for the acetohydrazide hydrazones. These compounds exist as a mixture of configurational and conformational isomerism as well as amido-amidic acid tautomerism. The NMR spectral data proved the predominance of syn-E amido isomers. In addition, density functional theory (DFT) predicted stability in the gas phase and showed that syn-E amido isomers are the most stable in the presence of an electron donating group, while the anti-isomer is the most stable in the presence of electron-attracting substituents. The anticancer activity of these synthetic compounds 6a, 6b and 6c towards both colon cancer (HCT-116) and cervical cancer (HeLa) cells was examined by MTT assay and DAPI staining. The MTT assay revealed a strong antiproliferative effect against the cancer cells at low concentrations, and interestingly, no significant inhibitory action against the non-cancerous cell line, HEK-293. The IC50 values for HCT-116 were 29.5 + 4.53 µM, 57.9 + 7.01 µM and 40.6 + 5.42 µM for 6a, 6b, and 6c, respectively. The IC50 values for HeLa cells were 57.1 + 6.7 µM, 65.6 + 6.63 µM and 33.8 + 3.54 µM for 6a, 6b, and 6c, respectively. DAPI staining revealed that these synthesized benzimidazole derivatives caused apoptotic cell death in both the colon and cervical cancer cells. Thus, these synthetic compounds demonstrate encouraging anticancer activity as well as being safe for normal human cells, making them attractive candidates as anticancer agents.  相似文献   
47.
Kienböck''s disease is a condition characterized by avascular necrosis of the lunate. It is also known as lunatomalacia and aseptic or ischemic necrosis of the lunate.The aim of this work is to summarize and illustrate, through a case diagnosed in our institution, the radiological aspects of this rare entity, which occupy a prominent place in the diagnosis.A better understanding of this recently described nosological entity and a wide dissemination of its diagnostic criteria, especially by radiologists, should facilitate the diagnosis and treatment of patients.  相似文献   
48.
In earlier studies, we have reported the presence of luteinizing hormone-releasing hormone (LH-RH) binding sites in different rat brain areas including the hippocampus, lateral septum, amygdaloid nucleus and subiculum. We have also demonstrated that sex steroids can modulate the concentrations of brain LH-RH receptors. The role of hormonal status during different stages of development in regulating hippocampal LH-RH receptor concentration was assessed using in vitro autoradiography performed on slide-mounted frozen sections. Labeling was measured quantitatively by optical densitometry. Female and male rats of different ages (from birth to 21 months of age) were used in these experiments. The results obtained were similar in both sexes. As early as 6 days of age, LH-RH binding sites could be detected. The concentration of receptors increased with time and reached a maximum at 35 and 45 days of age for male and female, respectively. Thereafter, the receptor concentrations decreased and were at their minimum in middle-age animals. In older rats (17 and 21 months of age), LH-RH binding sites increased in concentration. These results suggest that, at the time of puberty, hormonal status induces an increase in the density of brain LH-RH receptors whilst in older rats, as previously demonstrated in castrated animals, the decreased production of gonadal hormones results in an increase in receptor concentration.  相似文献   
49.
Objective: The purpose of the study was to correlate between effect of pre-neoadjuvant chemotherapy (NACT) and post-NACT clinical, sonographic and pathologic features of the tumor and axillary lymph nodes (ALNs) and to raise the possibility of applying the concept of sentinel lymph node biopsy (SLNB) in patients with initially positive ALNs before NACT. Methods: A prospective study of 50 female patients with locally advanced breast cancer (LABC) with clinically palpable.and cytologically (under ultrasonographic guidance) positive ALNs. All patients received NACT and then referred for ultrasono- graphic assessment of the axilla regarding any detectable sonographic criteria of metastatic deposits in ALNs as well as the tumor size in relation to its prechemotherapy size, All patients were then subjected either to modified radical mastectomy or breast conserving surgery. The clinical, sonographic and pathological response of the tumor and the ALNs were documented, classified and correlated with each other. Results: Patients' mean age was 47.7±9.1 years. The mean clinical tumor size was 6.7 ± 1.4 cm; stage IliA that was presented in 32 patients (64%) and IIIB was presented in 18 patients (36%). Chemotherapy was given for a median of 4 cycles, there was reduction of the mean clinical tumor size from 6.7 ± 1.4 cm to 4.3 ± 2.7 cm (P 〈 0.001). Clinical response was complete in 5 (10%) tumors, complete pathological tumor response (post-neoadjuvant) was detected in 6 (16%) of patients. Complete clinical nodal response (post-neoadjuvant) in 23 (46%) axillae, on sonographic assessment of the axilla, response was complete in 17 (34%) axillae. Complete pathological nodal response occurred in 16 (32%) axillae. Out of 17 axillae that showed complete sonographic response 11 axillae showed complete pathological nodal response (P 〈 0.001). Conclusion: Formal axillary lymph node dissection can be avoided and replaced by SLNB post NACT in patients with L  相似文献   
50.
Aim: The aim of the present study was to compare the direct and indirect cytotoxicity of a porcine dried acellular dermal matrix (PDADM) versus a porcine hydrated acellular dermal matrix (PHADM) in vitro. Both are used for periodontal and peri-implant soft tissue regeneration. Materials and methods: Two standard direct cytotoxicity tests—namely, the Trypan exclusion method (TEM) and the reagent WST-1 test (4-3-[4-iodophenyl]-2-[4-nitrophenyl]-2H-[5-tetrazolio]-1,3-benzol-desulphonated)—were performed using human primary mesenchymal stem cells (HPMSCs) seeded directly onto a PDADM and PHADM after seven days. Two standard indirect cytotoxicity tests—namely, lactate dehydrogenase (LTT) and MTT (3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazoliumbromide)—were performed using HPMSCs cultivated in eluates from the matrices incubated for 0.16 h (10 min), 1 h, and 24 h in a serum-free cell culture medium. Results: The WST and the TEM tests revealed significantly lower direct cytotoxicity values of HPMSCs on the PHADM compared with the PDADM. The indirect cytotoxicity levels were low for both the PHADM and PDADM, peaking in short-term eluates and decreasing with longer incubation times. However, they were lower for the PHADM with a statistically significant difference (p < 0.005). Conclusions: The results of the current study demonstrated a different biologic behavior between the PHADM and the PDADM, with the hydrated form showing a lower direct and indirect cytotoxicity.  相似文献   
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