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71.

Ethnopharmacological relevance

The role of Azadirachta indica (neem) against Chagas disease and its antibiotic and antidiabetic action have been demonstrated in non-pregnant animals. However, the effects of neem on lipid metabolism and oxidative stress during pregnancy remain to be investigated. The objective of this study was to evaluate the effects of Azadirachta indica (neem) on maternal reproductive performance and biochemical parameters in non-diabetic and streptozotocin-induced mild diabetic rats (MD).

Materials and methods

Pregnant rats were randomly distributed into six experimental groups: ND=non-treated non-diabetic (n=13); NDOil=non-diabetic treated with 1.2 mL/day neem seed oil (n=12); NDPA=non-diabetic treated with 1.0 mg/mL/day azadirachtin (n=12); D=non-treated diabetic (n=13); DOil: diabetic treated with neem seed oil (n=12), and DPA=diabetic treated with azadirachtin, n=13. Treatment with either neem oil (1.2 mL/day) or azadirachtin (1.0 mg/mL/day) was orally administered throughout pregnancy. Glucose test tolerance (GTT) was performed at day 17 of pregnancy and used as an inclusion criterion. At term pregnancy, maternal reproductive outcomes, lipid profile and oxidative stress status were assessed.

Results

Treatment with neem oil and azadirachtin during pregnancy (1) had no hypoglycemic and anti-hyperglycemic effects on non-diabetic and diabetic rats, respectively; (2) affected OGTT glycemic levels in diabetic rats; (3) increased the proportion of fetuses classified as small for pregnancy age (SPA) in all groups; and (4) did not interfere with the lipid profile in non-diabetic dams. Neem oil reduced the rate of total cholesterol and NEFA in diabetic animals. Both neem oil and azadirachtin increased lipoperoxidation, characterized by increased MDA levels in non-diabetic rats.

Conclusion

Both neem seed oil and azadirachtin impaired intrauterine development and altered antioxidant/oxidative status during pregnancy.  相似文献   
72.
Although stimulation of the periaqueductal gray (PAG) and microinjection of opiates or opioids into the PAG was reported to affect the activity of nucleus gigantocellularis (NGC) neurons, it is not known whether a direct pathway exists between these brain regions. The purpose of this investigation was to electrophysiologically test this possibility by attempting to antidromically activate PAG neurons from the NGC. Seventy neurons in the PAG of urethane-anesthetized rats were activated by electrical stimulation in the NGC and classified on the basis of the antidromicity criteria of constant latency, high following frequency, and collision. Of these neurons, 50 (71%) were classified as being transsynaptically activated, and 20 (29%) were classified as being antidromically activated. Ten neurons demonstrated collision between spontaneous action potentials and stimulation-evoked action potentials. Although most of the responses could not be tested with all criteria, the data support the existence of a monosynaptic pathway from the PAG to the NGC.  相似文献   
73.
Ammonia intoxication decreases the hyperpolarizing action of postsynaptic inhibition. This study examines the metabolic state of the spinal cord during this effect of ammonia intoxication on spinal motoneurons. ATP, ADP, AMP, the adenylate energy charge, glucose, PCr, pyruvate, alpha-ketoglutarate and glutamate were unchanged during the effect of ammonia on the hyperpolarizing action of postsynaptic inhibition. NH4+, glutamine and lactate were increased. Ammonia intoxication affected postsynaptic inhibition without changes of the resting membrane potential, the neuron input resistance, the action potential and EPSPs. The encephalopathy caused by ammonia intoxication is known to occur without an alteration of the tissue energy state. The effect of ammonia intoxication on postsynaptic inhibition can be considered as a cause of the encephalopathy because postsynaptic inhibition is altered without a change of the tissue energy state, the resting membrane potential, the whole neuron resistance, the action potential and EPSPs.  相似文献   
74.
75.
目的 构建免疫球蛋白结合分子金黄色葡萄球菌蛋白A(SPA)和链球菌蛋白G(SPG)单结构域随机组合噬菌体展示文库,为研究其分子功能与结构的关系奠定基础.方法 PCR扩增制备SPA的A、B、C 、D、 E结构域和SPG的B2结构域核苷酸片段,在片段两端通过引物引入XbaⅠ酶切位点和保护碱基,3′端引入3个氨基酸大小的随机连接肽核苷酸序列,各结构域核苷酸片段经XbaⅠ酶消化,在T4连接酶作用下随机相互连接并克隆于噬菌体展示载体pCANTAB5S,克隆产物转化E.coli DH5α,提取原代库质粒转化E.coli TG1,经M13K07辅助噬菌体拯救,构建成SPA和SPG单结构域随机组合噬菌体展示文库.结果 该噬菌体展示文库库容量为1.87×107 cfu,滴度为1.3×1014 TU/ml,文库的片段插入率近100%,其中插入多个结构域的阳性克隆占21.7%,序列分析显示各结构域之间的连接和随机连接肽序列具有随机性.结论 成功地构建了SPA和SPG单结构域随机组合噬菌体展示文库,该文库在库容量、多样性和随机性方面满足体外分子进化研究的要求.  相似文献   
76.
目的:探讨双阴性血清阴性脊柱关节病(Both Negative-Seronegtive Spondyloarthro Pathies BNSPA)的门诊诊治。方法20例具有SPA症状的患者HLA-B27检测全部报告阴性,骶髂关节影像学报告全部阴性,均按SPA的诊治思路做进一步检查治疗。结果经抗SPA治疗后,症状全部得以明显控制,无一例出现典型的骶髂关节影像学变化。结论国民体质的提高,早期抗SPA的干预是HLA-B27阴性频率较高的一个重要因素,而骶髂关节炎影像学的误判也是SIJ阳性率不高的一个重要原因。根据临床征象以BNSPA诊治,取得良好效果。  相似文献   
77.
Background  Access procedures for alimentation have been performed both endoscopically and surgically. In those patients in whom endoscopic tubes cannot be placed, the minimally invasive approach is a viable alternative. To minimize incisions and their sequelae, we have developed a single port access (SPA) technique in which minimal access surgery can be done through one portal of entry, often the umbilicus. Methods  We have used the SPA technique to place gastric feeding tubes in patients who are not candidates for PEG tubes due to supraglottic stenosis. We reviewed our experience in the first five procedures we performed. Results  In all five patients a gastrostomy tube was placed laparoscopically via an umbilical incision and a left-upper-quadrant tube insertion point. Mean operative time was 44 min. All patients began tube feeds on postoperative day 1. Conclusion  We present the first series of five SPA gastric tube placements, offering a viable alternative to PEG or open placement.  相似文献   
78.
Pregabalin is a synthetic amino acid compound effective in clinical trials for the treatment of post-herpetic neuralgia, diabetic peripheral neuropathy, generalized anxiety disorder and adjunctive therapy for partial seizures of epilepsy. However, the mechanisms by which pregabalin exerts its therapeutic effects are not yet completely understood. In vitro studies have shown that pregabalin binds with high affinity to the alpha(2)-delta (alpha(2)-delta) subunits (Type 1 and 2) of voltage-gated calcium channels. To assess whether alpha(2)-delta Type 1 is the major central nervous system (CNS) binding protein for pregabalin in vivo, a mutant mouse with an arginine-to-alanine mutation at amino acid 217 of the alpha(2)-delta Type 1 protein (R217A mutation) was generated. Previous site-directed mutagenesis studies revealed that the R217A mutation dramatically reduces alpha(2)-delta 1 binding to pregabalin in vitro. In this autoradiographic analysis of R217A mice, we show that the mutation to alpha(2)-delta Type 1 substantially reduces specific pregabalin binding in CNS regions that are known to preferentially express the alpha(2)-delta Type 1 protein, notably the neocortex, hippocampus, basolateral amygdala and spinal cord. In mutant mice, pregabalin binding was robust throughout regions where the alpha(2)-delta Type 2 subunit mRNA is abundant, such as cerebellum. These findings, in conjunction with prior in vitro binding data, provide evidence that the alpha(2)-delta Type 1 subunit of voltage-gated calcium channels is the major binding protein for pregabalin in CNS. Moreover, the distinct localization of alpha(2)-delta Type 1 and mutation-resistant binding (assumed to be alpha(2)-delta Type 2) in brain areas subserving different functions suggests that identification of subunit-specific ligands could further enhance pharmacologic specificity.  相似文献   
79.
BackgroundIn many parts of the world, hydrotherapy plays an important role in the management of patients with wounds including burns. Different centers practice hydrotherapy differently. At the University Teaching Hospital in Lusaka, Zambia, burn patients use a common bathtub for cleaning their wounds which theoretically increases the risk of cross-infection, an important source of morbidity and mortality. There is currently no evidence that hydrotherapy as practiced at our institution leads to cross infection among patients with burns.ObjectiveThe objective was to determine if our hydrotherapy practice and water plays a role in cross-infection and what organisms cause this infection.MethodsThis was a prospective analytical study. Patients meeting the selection criteria were recruited. Swabs from the burn wounds were collected on admission (day 0), day 4 and day 7. Weekly swabs of the bathtub were also collected, after the tub had been cleaned and declared ready for the next patient. Weekly water samples were also collected. Selected results, for Staphylococcus aureus and Klebsiella pneumoniae, were subjected to further analysis and PCR. Results were analyzed using statistics software, SPSS version 23.ResultsIn this study, there were 96 participants of which 51 (53.1%) were males and 45 (46.9%) were females. Age distribution ranged from 5months to 91 years. The modal age range was 1 to 2 years. The modal burn percentage was 6%–10%, followed by 11%–15%. Hot water was the cause of burns in 65.6%. S. aureus and K. pneumoniae were the most common organisms isolated. Others were enteric organisms. In terms of readily available antibiotics, there was more sensitivity to Amikacin and Chloramphenicol than Ciprofloxacin (our commonly used antibiotic). The bathtub also had S. aureus and K. pneumoniae, besides enteric organisms. Sixty five point four percent (65.4%) of the Klebsiella were ESBL (Extended Spectrum Beta Lactamase) producers. The tub had samples that were both ESBL producers as well as widely resistant Klebsiella by other means. No growth was obtained from the water samples. Seventy-two point nine percent (72.9%) of the patients were discharged, 19.8% died, while 7.3% left against medical advice.ConclusionHydrotherapy as currently practiced at the University Teaching Hospital does contribute significantly to cross-infection among burn patients with widely resistant organisms. The main ones are S. aureus and K. pneumoniae. Switching care to a shower mechanism might help eliminate this problem as the study demonstrates that no bacteria were found in the water samples.  相似文献   
80.
Levocabastine is an antiallergic drug acting as a histamine H1-receptor antagonist. In allergic conjunctivitis (AC), it may also antagonize up-regulation of the intercellular adhesion molecule-1 (ICAM-1) expressed on epithelial conjunctival cells. However, little is known about its effects on eosinophils, important effector cells in AC. The adhesion molecule integrin alpha(4)beta(1) is expressed in eosinophils; it interacts with the vascular cell adhesion molecule-1 (VCAM-1) and fibronectin (FN) in vascular endothelial cells and contributes to eosinophil activation and infiltration in AC. This study provides evidence that in a scintillation proximity assay levocabastine (IC(50) 406 microM), but not the first-generation antihistamine chlorpheniramine, displaced (125)I-FN binding to human integrin alpha(4)beta(1) and, in flow cytometry analysis, levocabastine antagonized the binding of a primary antibody to integrin alpha(4) expressed on the Jurkat cell surface. Levocabastine, but not chlorpheniramine, binds the alpha(4)beta(1) integrin and prevents eosinophil adhesion to VCAM-1, FN or human umbilical vascular endothelial cells (HUVEC) in vitro. Similarly, levocabastine affects alpha(L)beta(2)/ICAM-1-mediated adhesion of Jurkat cells. In a model of AC levocabastine eye drops reduced the clinical aspects of the late-phase reaction and the conjunctival expression of alpha(4)beta(1) integrin by reducing infiltrated eosinophils. We propose that blockade of integrin-mediated cell adhesion might be a target of the antiallergic action of levocabastine and may play a role in preventing eosinophil adhesion and infiltration in AC.  相似文献   
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