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1.
Dermonecrosis was induced in ICR mice by subcutaneous implantation of Staphylococcus aureus absorbed onto sterile cotton pellets. This model was used to assess the effects of marijuana smoke, marijuana placebo smoke and $DL9-tetrahydrocan-nabinol ($DL9-THC) on the local immune response to bacterial infection. Mice were exposed to 40 or 80 “puffs” of marijuana smoke, marijuana placebo smoke or air daily for 4 consecutive days. The estimated dose of $DL9THC per day generated from 40 or 80 puffs of marijuana smoke was 3.2 and 6.4 mg/kg, respectively. A group of sentinel (Shelf) control mice were included in each experiment. The necrotic index (NI) of mice exposed to 40 or 80 puffs of marijuana smoke were 67% and 44% of control, respectively. Air exposed mice showed a necrotic index comparable to the shelf control group. In chronically (60 days) exposed mice (80 puffs per day) the necrotic index was about 12% of control, while air-exposed mice were about 40% of control.

Placebo marijuana smoke exposed mice had a NI comparable to that of marijuana smoke exposed mice which suggested that the reduction in NI was unrelated to the pychomimetic component $DL9THC. To further explore which of the constituents of marijuana were responsible for the decreased NI, the ethanol extract from marijuana leaves was partioned between water (cannabinoid free) and chloroform (cannabinoid rich). Injection of the cannabinoid free fraction produced comparable decrease in the NI as observed with whole marijuana smoke, while the cannabinoid rich fraction produced no effect. $DL9THC at a dose of 10 mg/kg per day did not alter the NI.  相似文献   
2.
Background: Vitamin B12 deficiency after gastric surgery for obesity is due to a failure of separation of vitamin B12 from protein foodstuffs and to a failure of absorption of crystalline vitamin B12 in the presence of intrinsic factor. The purpose of this study was to determine which of four oral doses of crystalline vitamin B12 was most effective in treating vitamin B12 deficiency in 102 patients. Methods and Results: At time of entry into the study, the patients had a serum vitamin B12 < 100 pmol L −1, were 29.9 ± 21.7 months post-op, were 37 ± 8 years old and had a body mass index of 30 ± 6 kg m−2. Eight (8%) had had a vertical banded gastroplasty and 94 (92%) a gastric bypass. For the first 3 months all patients received 350 μg per day of crystalline vitamin B12 and all increased their serum vitamin B12 levels to over 100 pmol L−1. The patients were then assigned to receive for a further 3 month period one of four oral doses of crystalline vitamin B12-100 μg, 250 μg, 350 μg and 600 μg. Serum vitamin B12 levels were greater than 150 pmol L−1 after 6 months in 83.3% of patients who received 100 μg; 92.3% of patients who received 250 μg; 94.7% after 350 μg and 95.2% after 600 μg (p%0.525). Conclusion: At least 350 μg per day is the appropriate oral dose of crystalline vitamin B12 after gastric surgery for obesity to correct low serum vitamin B12 levels in 95% of patients.  相似文献   
3.
ETHNOPHARMACOLOGICAL RELEVANCE: Ginger rhizomes are used traditionally for management of different gastrointestinal disturbances. Several studies proved that the rhizome possesses diverse biological activities such as cytotoxic, antioxidant, and anti-inflammatory effects. Recently, interest in ginger for treatment of chronic inflammatory conditions has been renewed. AIM OF THE STUDY: The purpose of the present study is to evaluate the potential role of ginger extract [GE] in modulating the extent and severity of ulcerative colitis (UC), a chronically recurrent inflammatory bowel disease of unknown origin. MATERIALS AND METHODS: Male Wistar rats received 3 different doses of GE, sulfasalazine, or vehicle for 3 consecutive days before induction of UC by intra-rectal acetic acid administration, and continued further for 7 days after the induction. The colonic mucosal injury was assessed by macroscopic scoring, and histological examination. Furthermore, the mucosal content of malondialdehyde (MDA), protein carbonyl (PCO), and reduced glutathione (GSH) with the catalase (CAT) and superoxide dismutase (SOD) activity, were appraised as parameters of the redox state. Acute inflammatory response was determined by measuring myeloperoxidase (MPO), tumor necrosis factor (TNF-alpha), and prostaglandin E2 (PGE2). RESULTS: All parameters were altered in ulcerated rats, and improved in animals receiving GE, an effect that was comparable to that of the standard sulfasalazine, especially at the highest dose level. Colonic mucosal injury parallels with the histological and biochemical evaluations. CONCLUSIONS: Results showed a valuable effect of ginger extract against acetic acid-induced ulcerative colitis possibly by its antioxidant and anti-inflammatory properties.  相似文献   
4.

Objective

To assess trends in twinning over four decades using a population-based registry.

Design

Ecological study to conduct trend analysis of twin pregnancies in a geographically defined area over 40 years.

Setting

All pregnancies in the Cardiff and Vale of Glamorgan area of South Wales from 1965 to 2004, as recorded in the Cardiff Birth Survey (CBS) database.

Methods

Trends of the incidence of all twin pregnancies (≥18 weeks of gestation) were calculated in 5-year increments, beginning with 1965–1969 and ending in 2000–2004. Natural twinning rates could only be calculated for the terminal five time periods (i.e., 1980–1984, 1985–1989, 1990–1994, 1995–1999, and 2000–2004), when information regarding non-spontaneous (iatrogenic) twinning was first collected in the database. All results were adjusted for maternal age.

Results

The total twinning rate was 13.1 per 1000 pregnancies in the 1st time period (1965–1969). Subsequently, there was a gradual reduction in twinning, reaching a nadir of 10.3 per 1000 for the time period 1980–1985 (Z = 3.15, P value < 0.001). This was followed by a gradual increase in twinning, reaching a maximum of 15.7 per 1000 for both 1995–1999 and 2000–2004 (Z = −5.18, P value < 0.0001). After exclusion of the cases of iatrogenic pregnancies, the natural twinning rate showed a continuous and gradual increase from 10 per 1000 spontaneous pregnancies in 1980–1984 to 13.3 per 1000 in 2000–2004 (Z = −5.08, P value < 0.0001).

Conclusion

The data showed a gradual, continuous increase in natural twinning rates over the last two decades. Such an increase cannot be attributed to the rise in maternal age alone.  相似文献   
5.
Bio-based silica, lignocellulose, and activated carbon were simply produced via the recycling of Hassawi rice biomass waste of Al-Ahsa governorate in the eastern Saudi Arabia region using a fast chemical treatment procedure. Rice husk and rice straw wastes were collected, ground, and chemically treated with sodium hydroxide to extract silica/silicate from the dried plant tissues. The liquid extract is then treated with acid solutions in order to precipitate silica/silicate at neutral medium. Lowering the pH of the supernatant to 2 resulted in the precipitation of lignocellulose. Thermal treatment of the biomass residue under N2 gas stream resulted in activated carbon production. Separated products were dried/treated and characterized using several physical examination techniques, such as FT-IR, SEM/EDX, XRD, and Raman spectroscopy in order to study their structure and morphology. Silica and lignocelluloses products were then preliminarily used in the treatment of wastewaters and water-desalination processes.  相似文献   
6.
BackgroundAcne scars are a source of cosmetic concern for most of the patients.ObjectiveWe sought to compare the clinical efficacy and safety of topical botulinum toxin A (BTX-A) application immediately after microneedling (Mn) versus Mn with saline in the treatment of atrophic acne scars.MethodsForty patients with atrophic acne scars (rolling, boxcar, and mixed types) were enrolled in a split-face study; microneedling was performed on both sides of the face followed by an application of topically diluted botulinum toxin on one side (Side A) and saline on the other (Side B) for two sessions both two weeks apart. Evaluation was done at baseline, two and four weeks after the session. Follow-up was performed after six months. The assessments included blinded clinical assessment and patient’s satisfaction.ResultsAfter the treatment, acne scars in (Side A) showed 70 percent overall improvement versus zero percent in Side B (P<0.0001). A statistically highly significant reduction of acne scars severity occurred in (Side A) (P=0.0008). Patient’s satisfaction was higher in (Side A) (P<0.0001). No serious side effects were reported.ConclusionMicroneedling delivery of BTX-A could be simple, safe, and innovative modality improving the appearance and decrease the depth of atrophic acne scars.  相似文献   
7.
BACKGROUND: Obese patients may be sensitive to the respiratory depressant effect of opioid analgesics. Alternative methods for analgesia may be beneficial for management of bariatric surgery. We evaluated the effect of dexmedetomidine on anesthetic requirements during surgery, hemodynamic, recovery profile and morphine use in the postoperative period. METHODS: Eighty adult patients scheduled for elective laparoscopic Roux-en-Y gastric bypass surgery were randomly assigned to one of two study groups; Group D (40 patients) received dexmedetomidine (0.8-microg/kg bolus, 0,4 microg kg(-1) h) and Group P (40 patients) received normal saline (placebo) in the same volume and rate. Intraoperative and postoperative mean blood pressure and heart rate were recorded. The total amount of intraoperative fentanyl and propofol required to maintain anesthesia were measured. Recovery profile, pain score and total amount of morphine used via patient controlled analgesia (PCA) were assessed. RESULTS: During surgery, dexmedetomidine decreased the total amount of intraoperative fentanyl and propofol required for maintenance of anesthesia compared to placebo. Patients who received dexmedetomidine showed significant decrease of intraoperative and postoperative mean blood pressure, heart rate. In the postoperative period, dexmedetomidine decreased pain scores and PCA morphine use significantly and showed better recovery profile as compared to the placebo Group. There was no difference in the incidence of postoperative nausea and vomiting (PONV) between both groups. CONCLUSION: The intraoperative infusion of dexmedetomidine decreased the total amount of propofol and fentanyl required to maintain anesthesia, offered better control of intraoperative and postoperative hemodynamics, decreased postoperative pain level, decreased the total amount of morphine used and showed better recovery profile compared with placebo.  相似文献   
8.
INTRODUCTIONThis study aimed to investigate the therapeutic response to injected human umbilical cord blood mesenchymal stem cells (UCBMSCs) among albino rats with streptozotocin (STZ)-induced diabetes mellitus.METHODSControl group (GI; n = 25) rats were fed with standard rat diet. Rats with STZ-induced diabetes mellitus without (GII; n = 25) and with (GIII; n = 25) differentiated human UCBMSCs implantation were the test groups. Rats were sacrificed in Week 11 following implantation. Liver biopsies were sectioned and stained in order to highlight both the presence and function of impregnated cells in the liver tissue.RESULTSHaematoxylin and eosin-stained sections in GI and GII rats showed normal liver architecture while GIII rats showed presence of cell clusters inside the liver tissue and around the central veins. Cell clusters with blue cytoplasm were present in sections in GIII rats but absent in GI and GII rats, indicating the presence of injected differentiated human UCBMSCs. The anti-human insulin immunostaining of GIII rats showed clusters of cells within the liver parenchyma and around central veins, indicating that these cells were active and secreting insulin.CONCLUSIONUCBMSCs are proficient in differentiating into insulin-producing cells in vivo under specific conditions and, when transplanted into the liver of albino rats with STZ-induced diabetes mellitus, were able to secrete insulin and partially control the status of diabetes mellitus in rats.  相似文献   
9.
Cyclosporine A is one of the most widely used drugs in organ transplant and oncology patients. But its use is accompanied by many toxicities. This study aimed to investigate the possible protective effect of Costus afer (C. afer) leaf extract on cyclosporine A-induced testicular toxicity. This study was carried out on 40 adult male Wistar rats were divided into four groups: control, C. afer, cyclosporine A and cyclosporine A+ C. afer groups. The investigations include genital weight, sperm count and characters, serum luteinising hormone (LH) and testosterone, testicular tissue contents of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) and lipid peroxidation (MDA). Besides, a histopathological examination of testicular tissue stained with haematoxylin and eosin (H & E) was performed. Cyclosporine A+ C. afer group showed a significant increase in the genital weight, serum testosterone, sperm count, motility and viability. Besides, the extract significantly decreased testicular content of MDA and increased SOD, CAT and GSHPx. C. afer coadministration significantly decreased serum LH and sperm abnormalities and protected against testicular histopathological alterations. The extract showed a protective effect against testicular toxicity associated with cyclosporine A and that was through an antioxidant mechanism.  相似文献   
10.
OBJECTIVE: To compare the effects of epidural and intravenous fentanyl on breast feeding behaviors and fentanyl concentration in the colostrum after an analgesic dose. METHODS: This study was conducted at the Obstetrics Department of Kasr El-Aini Hospital-Cairo University, Cairo, Egypt. The studied mothers were 100 multipara, who have been subjected to cesarean section, and have a previous history of successful breast feeding. The study was conducted from May 2005 to May 2007. They were divided into 2 groups: group I included 50 patients who received epidural anesthesia with fentanyl, and group II included 50 patients who received spinal anesthesia with intravenous fentanyl, and both groups were observed for initial breast feeding behaviors of newborns, and fentanyl concentration in the colostrum at 45 minutes, and 24 hours after birth. RESULTS: The study included 100 multipara, 2 samples of colostrum were taken from each patients at 45 minutes, and at 24 hours. The levels of fentanyl concentration were greatest at 45 minutes of the initial sampling time, reaching 0.40+/-0.059 ng/ml in the epidural group, and 0.19+/-0.019 ng/ml in intravenous fentanyl group. There was no statistical difference in breast feeding behaviors at birth, or at 24 hours of age in both groups. CONCLUSION: Although the levels of fentanyl concentration were greatest at 45 minutes of the initial sampling time, it can be used safely as intravenous or epidural without affecting the initial breast feeding behaviors of the newborn.  相似文献   
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