全文获取类型
收费全文 | 240篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 65篇 |
基础医学 | 10篇 |
口腔科学 | 10篇 |
临床医学 | 20篇 |
内科学 | 18篇 |
皮肤病学 | 1篇 |
神经病学 | 4篇 |
特种医学 | 9篇 |
外科学 | 62篇 |
综合类 | 2篇 |
预防医学 | 24篇 |
眼科学 | 1篇 |
药学 | 7篇 |
肿瘤学 | 10篇 |
出版年
2022年 | 2篇 |
2021年 | 8篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 3篇 |
2013年 | 6篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 12篇 |
2007年 | 18篇 |
2006年 | 14篇 |
2005年 | 16篇 |
2004年 | 14篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 9篇 |
2000年 | 11篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1994年 | 4篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1960年 | 1篇 |
1941年 | 1篇 |
1939年 | 1篇 |
1937年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有244条查询结果,搜索用时 15 毫秒
21.
Perforation of a central venous catheter into the pelvis of the kidney: a rare complication 总被引:1,自引:0,他引:1
Most adverse events related to central venous catheter (CVC) use in severely ill neonates who require total parenteral nutrition (TPN) are caused by malposition of the tip of the catheter, followed by complications such as infection, sepsis, thrombosis or, rarely, perforation of the vessel. Malpositioned tip of a CVC into the renal vein followed by thrombosis is well known. We report two cases of perforation of a CVC into the renal pelvis. To prevent this complication, the value of intra- or postoperative use of fluoroscopy with injection of contrast medium through the catheter is discussed. 相似文献
22.
Carla M Stehr Tiffany L Linbo John P Incardona Nathaniel L Scholz 《Toxicological sciences》2006,92(1):270-278
Fipronil is a phenylpyrazole insecticide designed to selectively inhibit insect gamma-aminobutyric acid (GABA) receptors. Although fipronil is often used in or near aquatic environments, few studies have assessed the effects of this neurotoxicant on aquatic vertebrates at sensitive life stages. We explored the toxicological effects of fipronil on embryos and larvae using the zebrafish (Danio rerio) experimental model system. Embryos exposed to fipronil at nominal concentrations at or above 0.7 microM (333 mug/l) displayed notochord degeneration, shortening along the rostral-caudal body axis, and ineffective tail flips and uncoordinated muscle contractions along the body axis in response to touch. This phenotype closely resembles zebrafish locomotor mutants of the accordion class and is consistent with loss of reciprocal inhibitory neurotransmission by glycinergic commissural interneurons in the spinal cord. Consistent with the hypothesis that notochord degeneration may be due to abnormal mechanical stress from muscle tetany, the expression patterns of gene and protein markers specific to notochord development were unaffected by fipronil. Moreover, the degenerative effects of fipronil (1.1 microM) were reversed by coexposure to the sodium channel blocker MS-222 (0.6mM). The notochord effects of fipronil were phenocopied by exposure to 70 microM strychnine, a glycinergic receptor antagonist. In contrast, exposure to gabazine, a potent vertebrate GABA(A) antagonist, resulted in a hyperactive touch response but did not cause notochord degeneration. Although specifically developed to target insect GABA receptors with low vertebrate toxicity, our results suggest that fipronil impairs the development of spinal locomotor pathways in fish by inhibiting a structurally related glycine receptor subtype. This represents an unanticipated and potentially novel mechanism for fipronil toxicity in vertebrates. 相似文献
23.
Children aged 9-11, 12-14 or 15-17 months, respectively were vaccinated with a measles, mumps and rubella (MMR) vaccine and serum antibody responses and reactogenicity were compared. The data of 118 children could be analysed (group 1=9-11 months, n=46; group 2=12-14 months, n=29, group 3, 15-17 months, n=43). The only significant difference observed was for seroconversion against measles virus between group 1 and group 3 (84.8% vs 100%, p=0.012). No serious adverse events were reported. Local side reactions were mild, infrequent and independent of age. Immunisation against MMR is safe and effective even when administered before the currently recommended age of 12 months. 相似文献
24.
M S Myers C M Stehr O P Olson L L Johnson B B McCain S L Chan U Varanasi 《Environmental health perspectives》1994,102(2):200-215
Relationships between hepatic lesions and chemical contaminant concentrations in sediments, stomach contents, liver tissue, and bile were statistically evaluated in three species of bottomfish, English sole (Pleuronectes vetulus), starry flounder (Platichthys stellatus), and white croaker (Genyonemus lineatus), captured from 27 urban and nonurban sites on the Pacific Coast from Alaska to southern California. Lesions detected were neoplasms, preneoplastic foci of cellular alteration, nonneoplastic proliferative lesions, unique or specific degenerative/necrotic lesions, nonspecific degenerative/necrotic lesions, and hydropic vacuolation of biliary epithelial cells and hepatocytes. In general, lesion prevalences were significantly higher in all three species captured at chemically contaminated urban sites, and certain lesions had significantly higher relative risks of occurrence at urban sites in Puget Sound, San Francisco Bay, the vicinity of Los Angeles, and San Diego Bay. Concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, DDT and its derivatives, and chlordanes and dieldrin in sediment, stomach contents, liver, and fluorescent aromatic compounds in bile were significant risk factors for the occurrence of neoplastic, preneoplastic, nonneoplastic proliferative, and specific degenerative/necrotic lesions, as well as hydropic vacuolation. Fish age also had a significant influence on occurrence of several hepatic lesions, but gender was rarely a significant risk factor. These relationships provide strong evidence for the involvement of environmental contaminants in the etiology of hepatic lesions in several marine bottomfish species and clearly indicate the utility of these lesions as biomarkers of contaminant-induced effects in wild fish. 相似文献
25.
A Stehr D Scodacek H Wustrack M Steinbauer I T?pel K Pfister P M Kasprzak 《European journal of vascular and endovascular surgery》2008,35(2):190-5; discussion 196-7
OBJECTIVES: The aim of this prospective randomized study was to demonstrate the comparability of retrojugular access for carotid eversion endarterectomy compared to the conventional ventrojugular procedure. PATIENTS AND METHODS: Due to the expected minor and major complication rate of 5% in patients undergoing carotid surgery, a patient cohort of 600 study patients was planned. All patients underwent standard preoperative and postoperative assessment including clinical investigation and fiberoptic laryngoscopy. The 6 month follow-up examination included an evaluation of patient contentment, a duplex scan, clinical investigation and a fiberoptic laryngoscopy. RESULTS: After the first interim evaluation of 101 patients, the study was stopped because of a significant increase in temporary ipsilateral vocal cord motility dysfunction in the retrojugular access group (31% vs. 6%, p=0.0014). This early postoperative impairment was, however, not statistically significant at the follow-up examination at 6 months (2.4% vs. 0%). No other significant differences concerning major complications (death or stroke), other cranial nerve injuries, wound healing, or patient satisfaction was observed neither in the early postoperative phase nor at follow up. CONCLUSION: Due to the high incidence of temporary ipsilateral vocal cord dysfunction in patients undergoing retrojugular exposure of the carotid artery, we recommend the conventional ventrojugular approach, which can be performed by incision along the anterior border of the sternomastoid muscle or by transversal skin incision. 相似文献
26.
Andreas Deussen Annette Pexa Robert Loncar Sebastian N Stehr 《Clinical chemistry and laboratory medicine》2005,43(10):1007-1010
Homocysteine may have deleterious effects on the cardiovascular system. It has been hypothesized that these effects may be brought about by a decrease in the adenosine concentration via the S-adenosylhomocysteine hydrolase reaction. A requirement for this causal relationship is proof of a reduction in vascular adenosine concentration during conditions of elevated homocysteine concentrations. In the present communication we summarize published data obtained during systematic variation of the arterial homocysteine concentration. Most of the results reported show that an increase in homocysteine concentration to 100 microM is associated with a 20-50% decrease in vascular adenosine concentration and an increase in tissue S-adenosylhomocysteine level. Homocysteine effects on the adenosine concentration seem to be more pronounced under conditions of impaired oxygenation. Further experiments, in particular on organs and tissue that release high amounts of homocysteine, i.e., the liver, are warranted to study the potential effects of homocysteine on vascular and tissue adenosine concentrations and consequent effects on organ function. The evidence obtained may be relevant for future assessment of risk indicators in conjunction with homocysteine pathogenicity, which might potentially be extended to measurements of adenosine or S-adenosylhomocysteine levels. 相似文献
27.
Myocardial uptake and biodistribution of newly designed technetium-labelled fatty acid analogues 总被引:2,自引:0,他引:2
Heintz AC Jung CM Stehr SN Mirtschink P Walther M Pietzsch J Bergmann R Pietzsch HJ Spies H Wunderlich G Kropp J Deussen A 《Nuclear medicine communications》2007,28(8):637-645
PURPOSE: In an effort to develop 99mTc-labelled fatty acids (FAs) for myocardial metabolism and flow imaging, several Tc analogues according to the '3+1' and the '4+1' mixed-ligand approach were synthesized and myocardial extraction was evaluated in non-working isolated guinea pig hearts. An example of biodistribution patterns in guinea pigs was determined by using one FA analogue. METHODS: The coordination moieties contain a +5, respectively +3, oxidation state metal core attached to the end position of a FA chain. FA complexes of the '3+1' and the '4+1' mixed-ligand type were prepared and investigated using the isolated heart model. To estimate the diagnostic value of the analogue 99mTc-FAs, the biodistribution of one well-extracted FA was evaluated. RESULTS: The '4+1' FA compounds achieved the highest uptake rates of all the technetium FAs investigated. In particular, the '4+1' 99mTc-C11-FA achieved at least a 2-fold higher ventricular extraction of the applied activity than the established control tracers including omega-(p-[123I]iodophenyl)pentadecanoic FAs (BMIPP and IPPA) and Tc-MIBI. Furthermore, the '4+1' dodecanoic FA derivative and the thiadodecanoic FA derivative showed an extraction comparable to established 123I-labelled tracers. Biodistribution experiments performed for the thiadodecanoic FA derivative indicated a good heart/blood and heart/lung ratio and also a high uptake in the liver. In contrast, '3+1' 99mTc complexes showed a low myocardial extraction rate. Nevertheless, the differentiation in the extraction profile, which depends on the FA chain length and structure, indicates a specific heart uptake of these 99mTc-labelled FA derivatives as well. CONCLUSIONS: The excellent extraction rates found for '4+1' 99mTc-FAs indicate possibly promising structures for innovative myocardial tracers. 相似文献
28.
Stehr SN Knels L Weissflog C Schober J Haufe D Lupp A Koch T Heller AR 《Shock (Augusta, Ga.)》2008,29(2):167-172
Immunological interventions in endotoxemia and sepsis have been tested in experimental and clinical studies. Our group evaluated the effects of an immunoglobulin (Ig)M-enriched solution in an established model of Gram-negative bacteraemia. Ten New Zealand White rabbits (2-3 kg) were randomized to a treatment or control group. In both groups, LPS was infused at a rate of 40 mg kg(-1) h(-1). Immunoglobulin M-enriched solution (Pentaglobin; 2 mL kg(-1) h(-1)) was applied in the intervention group 15 min after beginning LPS infusion. 1 x 10(8) colony forming units of Escherichia coli were injected 30 min after LPS infusion was commenced. Baseline hemodynamic and respiratory parameters, blood E. coli concentration (30 min before and 1, 15, 30, 60, 90, 120, and 180 min after E. coli injection), polymorphonuclear neutrophil oxidative burst activity, and phagocytosis dead space (both 30 min before and 1, 15, 60, 120, and 180 min postinjection) were measured. Ex vivo phagocytosis activity was measured in a separate experiment and evaluated by electron microscopy. Diffuse alveolar damage (DAD) was measured. Organ colonization (kidney, lung, liver, spleen) was assessed in aseptic organ samples. Hemodynamic parameters did not differ between the two groups. Bacterial blood clearance was not influenced by application of IgM-enriched solution. Liver and spleen colonization was significantly reduced in the IgM group. Immunoglobulin M-enriched solution reduced in vitro residual phagocytosis capacity at 30, 90, and 180 min and improved respiratory burst at 180 min. Correspondingly, ex vivo phagocytosis activity as documented by electron microscopy was increased in the IgM group. The sum of all weighted DAD scores (except overdistension) was significantly better in the IgM group (23+/-5 vs. 30+/-8). Immunoglobulin M-enriched solution significantly improved six of seven DAD score parameters and reduced liver and spleen E. coli count. Residual phagocytosis capacity was significantly decreased in the IgM group, whereas burst activity was increased, pointing to an increased in vivo phagocytosis efficiency. Short-term IgM-enriched solution intervention had an especially beneficial effect on LPS-induced pulmonary histological changes. 相似文献
29.
Infectious conditions of the infantile genitals are a diagnostic challenge. One of the rare differential diagnoses is lymphocytoma cutis benigna. We report a case of borrelial lymphocytoma of the glans penis in a 9 year old boy. Based on this case, the clinical, diagnostic and therapeutic aspects of this rare form of dermatoborreliosis are discussed. 相似文献
30.
BACKGROUND & AIMS: Normal intestinal adaptation to massive small-bowel resection requires intact epidermal growth factor receptor signaling and consists of increased enterocyte proliferation and apoptosis. Although emphasis has been placed on understanding the regulation of proliferation, few studies have evaluated the mechanism and contribution of apoptosis to the adaptation response. We sought to test the hypothesis that epidermal growth factor receptor signaling regulates specific Bcl-2 family members (Bax and Bcl-w) to direct apoptosis and adaptation after massive small-bowel resection. METHODS: Laser capture microdissection microscopy permitted measurement of Bax and Bcl-w messenger RNA expression in crypt and villus enterocytes in control conditions and under epidermal growth factor receptor-inhibited (waved-2 mice) or stimulated (epidermal growth factor transgenic mice) conditions after a 50% small-bowel resection or sham operation. Resection-induced adaptation was then studied in Bax-null and Bcl-w-null mice under control circumstances and after epidermal growth factor receptor stimulation. RESULTS: When compared with Bcl-w, the most significant expression changes were observed with Bax and took place within crypt enterocytes. Epidermal growth factor receptor stimulation resulted in a decreased ratio of Bax to Bcl-w expression and decreased rates of apoptosis. Bax-null mice had no apoptosis response to small-bowel resection and displayed an amplified adaptation response to the administration of epidermal growth factor. Bcl-w-null mice had poor survival and impaired adaptation to small-bowel resection, an effect that was rescued by crossbreeding these mice with epidermal growth factor transgenic mice. CONCLUSIONS: The crypt expression of Bax and Bcl-w is influenced by epidermal growth factor receptor signaling and is key for the regulation of apoptosis. Epidermal growth factor receptor stimulation, coupled with apoptosis inhibition, may provide a novel strategy to amplify adaptation responses in patients after massive intestinal loss. 相似文献