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1.
本文报道pH指示剂吸收度比值法测定盐酸乙胺丁醇的含量。该法采用指示剂为0.05%茜素黄R,测定波长374nm和500nm;标准液为0.1mol/L NaOH;仪器为WFZ-800D_2型分光光度计。测得三批盐酸乙胺丁醇的含量分别为99.5±0.04%,99.4±0.05%和99.6±0.03%.同时与药典法比较,结果一致。  相似文献   
2.
Bacterial DNA stimulates macrophages, monocytes, B lymphocytes, NK cells, and dendritic cells in a CpG-dependent manner. In this work we demonstrate that bacterial DNA, but not mammalian DNA, induces human neutrophil activation as assessed by L-selectin shedding, CD11b upregulation, and stimulation of cellular shape change, IL-8 secretion, and cell migration. Induction of these responses is not dependent on the presence of unmethylated CpG motifs, as neutrophil stimulatory properties were neither modified by CpG-methylation of bacterial DNA nor reproduced by oligonucleotides bearing CpG motifs. We found that human neutrophils express Toll-like receptor (TLR) 9 mRNA. However, as expected for a CpG-independent mechanism, activation does not involve a TLR9-dependent signaling pathway; neutrophil stimulation was not prevented by immobilization of bacterial DNA or by wortmannin or chloroquine, two agents that inhibit TLR9 signaling. Of note, both single-stranded and double-stranded DNA were able to induce activation, suggesting that neutrophils might be activated by bacterial DNA at inflammatory foci even in the absence of conditions required to induce DNA denaturation. Our findings provide the first evidence that neutrophils might be alerted to the presence of invading bacteria through recognition of its DNA via a novel mechanism not involving CpG motifs.  相似文献   
3.
Omenn syndrome is a combined immunodeficiency characterized by a generalized erythematous skin rash, enlarged lymph nodes, hepatosplenomegaly, severe susceptibility to infections, eosinophilia, and hyperimmunoglobulinemia E. A 3‐month‐old girl was admitted to our hospital with a history of recurrent sepsis. Physical examination revealed severe erythroderma, hepatosplenomegaly, lymphadenopathy, and failure to thrive. Laboratory findings revealed leukocytosis, lymphocytosis with high CD3 T‐cells, a high CD4:CD8 ratio, absence of CD19 B‐cells, high eosinophil count, and low immunoglobulin levels. A heterozygote RAG1 gene mutation was found. She had itchy, scaling, ichthyosiform erythroderma and protracted diarrhea. Cyclosporin treatment up to 10 mg/kg effectively resolved erythroderma and lowered total eosinophil counts, and she gained weight during treatment. Since extensive erythroderma with generalized itching causes patient discomfort in Omenn syndrome, cyclosporin treatment can be considered while waiting for treatment with hematopoietic stem cell transplantation.  相似文献   
4.
Endometriosis is characterized by the presence of endometrial tissue outside the uterus that causes severe pelvic pain and infertility in women of reproductive age. Although not completely understood, the pathophysiology of the disease involves chronic dysregulation of inflammatory and vascular signalling. In the quest for novel therapeutic targets, we investigated the involvement of galectin‐1 (Gal‐1), an endogenous glycan‐binding protein endowed with both immunosuppressive and pro‐angiogenic activities, in the pathophysiology of endometriotic lesions. Here we show that Gal‐1 is selectively expressed in stromal and endothelial cells of human endometriotic lesions. Using an experimental endometriosis model induced in wild‐type and Gal‐1‐deficient (Lgals1?/?) mice, we showed that this lectin orchestrates the formation of vascular networks in endometriotic lesions in vivo, facilitating their ectopic growth independently of vascular endothelial growth factor (VEGF) and the keratinocyte‐derived CXC‐motif (CXC‐KC) chemokine. Targeting Gal‐1 using a specific neutralizing mAb reduced the size and vascularized area of endometriotic lesions within the peritoneal compartment. These results underline the essential role of Gal‐1 during endometriosis and validate this lectin as a possible target for the treatment of disease. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
5.
The purpose of this study was to investigate the relationship between P gingivalis, T forsythia, T denticola, P intermedia, and A. actinomycetemcomitans in the sulci or pockets of patients with gingivitis (G), mild chronic periodontitis (MiCP), moderate chronic periodontitis (MoCP) and severe periodontitis (SP), and the expression of TNF-alpha in gingival tissue associated with clinical parameters. Six patients with G, 7 with MiCP, 23 with MoCP and 7 with SP were recruited. Pathogens obtained from the sulci or pockets were identified by PCR, and expression of TNF-alpha from gingival tissue was analysed Probing depth (PD), clinical attachment level (CAL) and loss of bone were recorded. P gingivalis was detected at the following rates: 16.6% in subjects with G 57.1% in MiCP 57.8 % in MoCP and 58.1% in SP (p < 0.05). P intermedia was not identified in subjects with G A. actinomycetemcomitans was only identified in subjects with MoCP (31.5%) and SP (42.8%). T denticola and T forsythia were identified in all subject groups. Bacterial combinations were identified as follows: P denticola + P intermedia and PR intermedia + T forsythia were associated (p = 0.04, p = 0.02) with the presence of TNF-alpha mRNA in 20% and 25% of subjects, respectively. P gingivalis + A. Actinomycetemcomitans andA. actinomycetemcomitans + T forsythia were associated with severe PD and CAL, respectively. The association between the presence of P intermedia and expression levels of TNF-alpha was significant (p = 0.05). These results indicate that the proportion of patients with P gingivalis increases with the progression of disease. We observed that the presence of P intermedia may trigger the expression of TNF-alpha and cause a worsening of the patient's clinical status.  相似文献   
6.
Controlled drug delivery aims to achieve an effective drug concentration in the action site for a desired period of time, while minimizing side effects. In this contribution, biodegradable poly(3-hydroxybutyrate) films were evaluated as a reservoir platform for dexamethasone controlled release. These systems were morphological and physicochemically characterized. In vitro release assays were performed for five different percentages of drug in the films and data were fitted by a mathematical model developed and validated by our research group. When the profiles were normalized, a single curve properly fitted all the experimental data. Using this unique curve, the dissolution efficiency (DE), the time to release a given amount of drug (tX%), and the mean dissolution time were calculated. Furthermore, the dissolution rate, the initial dissolution rate (a%) and the intrinsic dissolution rate were determined. The a% mean value was 1.968 × 10?2% released/min, t80% was about 14 days, and the DE was 59.6% at 14 days and 66.5% at 20 days. After 2 days, when approximately 40% of the drug was released, the dissolution rate decreased about 60% respect to the initial value. The poly(3-hydroxybutyrate) platforms behaved as an appropriate system to release and control the dexamethasone delivery, suggesting that they could be an alternative to improve drug therapy.  相似文献   
7.
The aim of this study was to determine whether early demyelination can impact behavior in young adulthood. For this purpose, albino Wistar rats of either sex were exposed to cuprizone (CPZ) in two different intoxication protocols: one group was intoxicated before weaning (CPZ‐BW), from postnatal day 7 (P7) to P21, through maternal milk, whereas the other group was intoxicated after weaning (CPZ‐AW), from P21 to P35. After treatment, rats were returned to a normal diet until P90 when behavioral studies were performed. Both treatments produced marked demyelination in the corpus callosum and retraction of cortical myelin fibers. The subsequent normal diet allowed for effective remyelination at P90. Interestingly, CPZ‐AW correlated with significant behavioral and neurochemical changes in a gender‐dependent manner. CPZ‐AW treatment altered both the number of social activities and the latency to the first social interaction in males, while also highly compromising recognition‐related activities. In addition, only P90 males treated AW showed a hyperdopaminergic striatum, confirmed by an increase in tyrosine hydroxylase expression and in dopamine levels. Our results suggest that the timing of demyelination significantly influences the development of altered behavior, particularly in adult males. GLIA 2014;62:1629–1644  相似文献   
8.
目的:探讨直肠前突病例的手术术式和治疗结果。方法:48例中,重度直肠前突采用经肛门直肠前壁切开将肌肉串联黏膜重叠缝合修补术,同时常规将内括约肌挑出切断术,包括耻骨直肠肌部分切除术和肠疝经腹切除冗长肠段,作对端缝合,疗效观察。结果:全部病例经6个月至2年的随诊,复查,排便通畅,临床症状消失,效果优者35例,良好11例,术后症状轻度改善2例,症状改善总有效率95.8%。结论:选择性直肠前突施行经肛门直肠前壁黏膜切开,肌肉串联,黏膜重叠缝合术效果满意,黏膜的分离,串联重叠缝合程度是手术成功的关键。  相似文献   
9.
10.
There is an increasing interest in the involvement of trace elements such as zinc in the pathogenesis of cardiovascular diseases. This study was designed to examine whether moderate zinc deficiency during growth influences blood pressure (BP) and vascular nitric oxide (NO) pathway. Three-week-old weaned male Wistar rats were randomly divided into two dietary groups and fed either a moderately zinc-deficient diet (zinc content 9 mg/kg; n = 12) or a control diet (zinc content 30 mg/kg; n = 12) for 60 d. The following were measured: systolic BP, nitrates and nitrites urinary excretion, urinary chemiluminescence intensity, NADPH-diaphorase activity in the thoracic aorta and intestinal arterioles, and NO synthase (NOS) catalytic activity using L-[U14C]-arginine as substrate in the thoracic aorta. Zinc deficiency during growth induced an increase in BP from day 30 of the experimental period, leading to hypertension on day 60. Animals that were fed the zinc-deficient diet had lower urinary excretion levels of nitrates and nitrites and higher intensity of spontaneous luminescence on day 60. At the end of the experiment, zinc-deficient rats showed decreased NADPH diaphorase activity in endothelium and smooth muscle of the thoracic aorta and intestinal arterioles and decreased activity of NOS in thoracic aortic tissue. An imbalance in zinc bioavailability during postnatal and growing periods may be may be a risk factor in development of cardiovascular alterations in adult life. The mechanisms involved may include an impaired vascular NO system as a result of decreased NOS activity and higher systemic oxidative stress.  相似文献   
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