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1.
Allergic airway diseases induced by low molecular weight (LMW) chemicals, including trimellitic anhydride (TMA), are characterized by airway mucus hypersecretion and an infiltration of eosinophils and lymphocytes. Many experimental models have linked LMW chemical-induced allergic airway disease to Th2 cytokines. Most murine models, however, use dermal exposure to sensitize mice. The present study was designed to test the hypothesis that intranasal sensitization and challenge with the known chemical respiratory allergen TMA, but not the nonrespiratory sensitizers dinitrochlorobenzene (DNCB) and oxazolone (OXA), will induce characteristic features of LMW chemical-induced allergic airway disease in the nasal and pulmonary airways. A/J mice were intranasally sensitized and challenged with TMA, DNCB, or OXA. Only mice that were intranasally sensitized and challenged with TMA had a marked allergic rhinitis with an influx of eosinophils, lymphocytes, and plasma cells, increased intraepithelial mucusubstances, and a regenerative hyperplasia. Cytokine mRNA levels in the nasal airway of TMA treated mice also revealed an increase in the mRNA levels of the Th2 cytokines IL-4, IL-5, and IL-13, but no change in the level of the Th1 cytokine IFN-gamma. No lesions were found in the nasal airways of mice exposed to DNCB or OXA. TMA increased lung-derived IL-5 mRNA while DNCB and OXA caused no change in lung-derived cytokine mRNA levels. Both TMA and DNCB caused increases in total serum IgE, unlike OXA-exposed mice. However, no adverse alterations were found microscopically in the lungs of mice treated with TMA, DNCB, or OXA. This study is the first to demonstrate that intranasal administration of a known chemical respiratory allergen is an effective method of sensitization resulting in the hallmark features of allergic rhinitis after challenge with a concomitant increase in nasal airway-derived Th2 cytokine mRNA, lung-derived IL-5 mRNA, and total serum IgE. In contrast, DNCB and OXA failed to elicit the pathologic changes in the nasal airways and cytokine changes in the lung. This model may be useful for identifying other chemical respiratory allergens.  相似文献   
2.
Deep brain stimulation (DBS) has emerged as a viable therapy for Parkinson’s disease (PD). The impact of subthalamic nucleus (STN) lead placement (lateral versus medial) on motor outcome, however, has not been systematically evaluated. Forty-eight patients with PD underwent STN-DBS surgery and were evaluated postoperatively for 48 weeks for motor improvement as measured by the Unified Parkinson’s Disease Rating Scale (UPDRS) part III (standardized motor examination) and levodopa equivalent daily dose (LEDD). Postoperative MRI was used to identify the location of the active stimulating contact and motor outcome was analyzed. STN-DBS was associated with significant improvement in motor outcome as determined by a reduction in the UPDRS part III subscore from 34.44 ± 1.29 at baseline to 18.76 ± 1.06 at end visit (p < 0.0001) and a reduction in LEDD from 1721 ± 152 mg/day at baseline to 1134 ± 119 mg/day at end visit (p = 0.0024). Patients with stimulating contacts in the medial STN compared to the lateral STN did not demonstrate any significant differences in motor outcome (UPDRS, p = 0.5811; LEDD, p = 0.7341). No significant differences were found in motor outcome between patients with STN stimulation compared to stimulation of surrounding fiber tracts (p = 0.80). No significant difference in stimulation voltage was noted with respect to lead location. Our study did not find a significant effect for the location of active contact and motor outcome neither within the subregions of the STN nor between the STN and surrounding fibers. Further research is needed to better understand the neurophysiological basis for these results.  相似文献   
3.
Alcohol withdrawal syndrome (AWS) is a potentially fatal outcome of severe alcohol dependence that presents a significant challenge to treatment. Although AWS is thought to be driven by a hyperglutamatergic brain state, benzodiazepines, which target the GABAergic system, comprise the first line of treatment for AWS. Using a rat model of ethanol withdrawal, we tested whether ceftriaxone, a β-lactam antibiotic known to increase the expression and activity of glutamate uptake transporter EAAT2, reduces the occurrence or severity of ethanol withdrawal manifestations. After a 2-week period of habituation to ethanol in two-bottle choice, alcohol-preferring (P) and Wistar rats received ethanol (4.0 g/kg) every 6 h for 3–5 consecutive days via gavage. Rats were then deprived of ethanol for 48 h during which time they received ceftriaxone (50 or 100 mg/kg, IP) or saline twice a day starting 12 h after the last ethanol administration. Withdrawal manifestations were captured by continuous video recording and coded. The evolution of ethanol withdrawal was markedly different for P rats vs Wistar rats, with withdrawal manifestations occurring >12 h later in P rats than in Wistar rats. Ceftriaxone 100 mg/kg per injection twice per day (200 mg/kg/day) reduced or abolished all manifestations of ethanol withdrawal in both rat variants and prevented withdrawal-induced escalation of alcohol intake. Finally, ceftriaxone treatment was associated with lasting upregulation of ethanol withdrawal-induced downregulation of EAAT2 in the striatum. Our data support the role of ceftriaxone in alleviating alcohol withdrawal and open a novel pharmacologic avenue that requires clinical evaluation in patients with AWS.  相似文献   
4.

Purpose

The purpose of this study was to characterize the growth rate of sacrococcygeal teratomas (SCTs) and determine its relationship to adverse outcomes.

Methods

A retrospective review of all pathology-confirmed isolated SCT patients evaluated with at least two documented ultrasounds and followed through hospital discharge between 2005 and 2012 was conducted. SCT growth rate was calculated as the difference between tumor volumes on a late- and early-gestation ultrasound divided by the difference in time. Outcomes were death, high-output cardiac failure (HOCF), hydrops, and preterm delivery. Student's t-test, receiver operator characteristics, Fisher's Exact test, and Pearson's correlation were performed.

Results

Of the 28 study subjects, there were 3 in utero demises and 2 neonatal deaths. Significantly faster SCT growth rates were seen in all adverse outcomes, including death (p < 0.0001), HOCF (p = 0.005), and preterm delivery (p = 0.009). There was a significant association with adverse outcomes at > 61 cm3/week (AUC = 0.87, p = 0.001, LR = 4.52). Furthermore, there was an even greater association with death at > 165 cm3/week (AUC = 0.93, p = 0.003, LR = 18.42). Growth rate was directly correlated with the percent of solid tumor (r = 0.60, p = 0.0008).

Conclusion

Faster SCT growth is associated with adverse outcomes. SCT growth rate determined by ultrasound is an effective prognostic indicator for adverse outcomes and easily applied to patient management.  相似文献   
5.
Marine natural products have as of now been acknowledged as the most important source of bioactive substances and drug leads. Marine flora and fauna, such as algae, bacteria, sponges, fungi, seaweeds, corals, diatoms, ascidian etc. are important resources from oceans, accounting for more than 90% of the total oceanic biomass. They are taxonomically different with huge productive and are pharmacologically active novel chemical signatures and bid a tremendous opportunity for discovery of new anti-cancer molecules. The water bodies a rich source of potent molecules which improve existence suitability and serve as chemical shield against microbes and little or huge creatures. These molecules have exhibited a range of biological properties antioxidant, antibacterial, antitumour etc. In spite of huge resources enriched with exciting chemicals, the marine floras and faunas are largely unexplored for their anticancer properties. In recent past, numerous marine anticancer compounds have been isolated, characterized, identified and are under trials for human use. In this write up we have tried to compile about marine-derived compounds anticancer biological activities of diverse flora and fauna and their underlying mechanisms and the generous raise in these compounds examined for malignant growth treatment in the course of the most recent quite a long while.  相似文献   
6.
This study ascertains the effects of zinc, a major component of particulate matter, on pulmonary and systemic endpoints using hyperlipidemic rabbits to model diet-induced human atherosclerosis. New Zealand White rabbits were fed a normal or cholesterol-enriched diet and then were intratracheally instilled 1×/week for 4 weeks with saline or 16 μg/kg of zinc, equal parts sulfate and oxide. Physiologic responses, blood after each exposure, and terminal bronchoalveolar lavage (BAL) were assessed. Rabbits fed a cholesterol-rich diet developed hyperlipidemia and had consistently higher circulating leukocyte counts than rabbits fed normal chow. Within minutes after zinc instillation, saturation of peripheral oxygen was decreased in hyperlipidemic rabbits and heart rate was increased in hyperlipidemic rabbits with total serum cholesterol levels greater than 200 mg/dl. Total circulating leukocytes levels were increased 24 h after the first zinc instillation, but upon repeated exposures this effect was attenuated. After repeated zinc exposures, BAL fluid (BALF) N-acetylglucosaminidase activity was increased regardless of hyperlipidemic state. Hyperlipidemic rabbits had an increase in BALF-oxidized glutathione and a decrease in serum nitrite. The study elucidates mechanisms by which the zinc metal component of PM drives cardiovascular health effects, as well as the possible susceptibility induced by hyperlipidemia. Furthermore, the study exemplifies the benefits of monitoring circulatory physiology during exposure as well as after exposure. This article was reviewed by the National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. A. P. Carll and N. D. Manzo supported by EPA-CT82947101 and EPA-CT826512010, respectively.  相似文献   
7.
8.
Background/Purpose: In utero hematopoietic stem cell transplantation (IUHSCTx) has been experimentally or clinically effective only in circumstances in which there is a survival advantage for donor cells. A survival advantage exists for normal muscle cells in muscular dystrophy. Because hematopoietic and mesenchymal stem cells may have the capacity to differentiate into muscle cells, the authors hypothesized that in utero bone marrow (BM) or fetal liver (FL) stem cell transplantation may be used to treat muscular dystrophy. Methods: Time-dated 14-day-gestation fetal muscular dystrophy mice (mdx) were injected intraperitoneally with 1 to 5 [times ] 106 BM or FL cells per fetus from Rosa26 donor mice (transgenic for lacZ). Four weeks after birth, peripheral blood from the pups was analyzed for hematopoietic chimerism by using fluorescence-activated cell sorting (FACS) for the Ly-9.1 marker. Chimeric mice (6 BM and 2 FL recipients) were sacrificed at 12 to 14 months of age, muscles were stained with X-gal, and analyzed by 1- to 2-[mu ]m plastic sections. Polymerase chain reaction (PCR) for lacZ was performed in other organs to determine systemic engraftment. Results: At the time of death, all animals that were chimeric at 4 weeks continued to show hematopoietic chimerism of 0.2% to 9% by FACS. Engrafted donor cells were found in multiple sections from hindlimb skeletal muscles, diaphragms, and hearts from both BM and FL recipients. These cells had incorporated into the host muscles, and their morphology was consistent with myogenic differentiation. PCR of BM, liver, spleen, thymus, kidney, and lung for lacZ was positive in multiple animals. Conclusions: IUHSCTx leads to widespread engraftment of donor cells in multiple muscle compartments of hematopoietic chimeras. The advantage for normal myocytes offered in the mdx model allows engraftment and myogenic differentiation of transplanted BM or FL cells by morphology at a relatively higher frequency in muscle relative to other tissues, without the need for host conditioning. Because muscular dystrophy now can be detected early in gestation, such a strategy may offer a future alternative in the clinical treatment of this disease. J Pediatr Surg 37:1058-1064.  相似文献   
9.
A 12-year-old boy was operated upon for torsion of a hernia sac invaginating into the tunica vaginalis. His clinical presentation resembled that of testicular torsion. Correspondence to: K. Kimura  相似文献   
10.
Bone marrow tissue engineering   总被引:1,自引:0,他引:1  
The creation of mixed hematopoietic chimerism has become an important clinical strategy for tolerance induction for cellular and organ transplantation, and for the treatment of numerous hematopoietic diseases. Clinical success has been limited however, by host immune response and by competition from host hematopoiesis. Recent data suggests that limited donor stem cell engraftment after minimally myeloablative hematopoietic stem cell (HSC) transplantation may in part be due to MHC associated microenvironmental mismatch resulting in a competitive disadvantage for donor HSC. A strategy to overcome this barrier to stable mixed hematopoietic chimerism would involve concurrent transplantation of a donor bone marrow microenvironment. To test this possibility, we set out to develop a method to tissue engineer a bone marrow microenvironment. One to two murine femurs were mechanically crushed to a fine suspension and were combined in vitro with various delivery vehicles. These constructs were transplanted into syngeneic animals in locations that are known to support transplantation of other tissues. Although bone formation was observed with several conditions, bone marrow formation was noted only within the small bowel mesentery when type I collagen was used as the delivery vehicle. No bone marrow formed when the vehicle was changed to polyglycolic acid or type IV collagen. We have demonstrated that the small bowel mesentery can support bone marrow formation under specific in vivo conditions. Future work will focus on strategies for transplantation of an engineered donor bone marrow environment to facilitate creation of allogeneic mixed hematopoietic chimerism.  相似文献   
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