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101.
Sphincter pharyngoplasty is frequently used for the management of children with velopharyngeal insufficiency. The purpose of this study was to evaluate outcome and revision rates of sphincter pharyngoplasty at the authors' institution. Two hundred fifty patients underwent sphincter pharyngoplasty for velopharyngeal insufficiency between January of 1987 and March of 2001. There were 117 female patients and 133 male patients, with a mean age at primary sphincter pharyngoplasty of 7.6 years (range, 1 to 45 years). Diagnoses included velopharyngeal insufficiency alone (n = 63), velopharyngeal insufficiency associated with cleft palate (n = 127), velocardiofacial syndrome (n = 32), submucous cleft (n = 15), and other (n = 13). Pharyngoplasty revision was defined as any secondary surgical revision of the sphincter as determined by clinical evaluation and objective speech assessment. The pharyngoplasty revision rate was found to be 12.8 percent (n = 32). A favorable outcome was demonstrated in 30 of these patients (93.8 percent) after pharyngoplasty revision. Two patients, one with a diagnosis of a submucous cleft and velocardiofacial syndrome and the other with a cleft palate, required a second revision because of persistent velopharyngeal insufficiency. The revision rate was highest in those patients with velocardiofacial syndrome (21.8 percent) and lowest in patients with velopharyngeal insufficiency alone (6.3 percent). Patients who required revision had significantly higher preoperative oral sentence nasometry (55.2 percent versus 46.1 percent; p < 0.01) and larger velopharyngeal areas (23.7 mm2 versus 18.9 mm2). There was no significant difference in age or sex for those patients who required a revision compared with those who did not require revision. Mean follow-up was 2.4 years (range, 4 months to 13.6 years). Sphincter pharyngoplasty is an effective procedure for the treatment of velopharyngeal insufficiency using revision rate as the standard of success. It had an 87 percent primary success rate that increased to 99 percent after a single revision. Patients with velocardiofacial syndrome, more severe preoperative hypernasal resonance, and larger velopharyngeal areas were more likely to require pharyngoplasty revision.  相似文献   
102.
BACKGROUND: Links between etiology/pathogenesis of neuropsychiatric disease and infection are increasingly recognized. AIM: Proof-of-principle that infection contributes to idiopathic parkinsonism. METHODS: Randomized, double-blind, placebo-controlled efficacy study of proven Helicobacter pylori eradication on the time course of facets of parkinsonism. Intervention was 1 week's triple eradication therapy/placebos. Routine deblinding at 1 year (those still infected received open-active), with follow-up to 5 years post-eradication. Primary outcome was mean stride length at free-walking speed, sample size 56 for a difference, active vs. placebo, of 3/4 (between-subject standard deviation). Recruitment of subjects with idiopathic parkinsonism and H. pylori infection was stopped at 31, because of marked deterioration with eradication failure. Interim analysis was made in the 20 who had reached deblinding, seven of whom were receiving antiparkinsonian medication (long-t(1/2), evenly spaced) which remained unchanged. RESULTS: Improvement in stride-length, on active (n = 9) vs. placebo (11), exceeded size of effect on which the sample size was calculated when analyzed on intention-to-treat basis (p = .02), and on protocol analysis of six weekly assessments, including (p = .02) and excluding (p = .05) those on antiparkinsonian medication. Active eradication (blind or open) failed in 4/20, in whom B-lymphocyte count was lower. Their mean time course was: for stride-length, -243 (95% CI -427, -60) vs. 45 (-10, 100) mm/year in the remainder (p = .001); for the ratio, torque to extend to flex relaxed arm, 349 (146, 718) vs. 58 (27, 96)%/ year (p < .001); and for independently rated, visual-analog scale of stance-walk videos (worst-best per individual identical with 0-100 mm), -64 vs. -3 mm from anterior and -50 vs. 11 lateral (p = .004 and .02). CONCLUSIONS: Interim analysis points to a direct or surrogate (not necessarily unique) role of a particular infection in the pathogenesis of parkinsonism. With eradication failure, bolus release of antigen from killed bacteria could aggravate an effect of ongoing infection.  相似文献   
103.

Background  

Many three-dimensional (3D) images are routinely collected in biomedical research and a number of digital atlases with associated anatomical and other information have been published. A number of tools are available for viewing this data ranging from commercial visualization packages to freely available, typically system architecture dependent, solutions. Here we discuss an atlas viewer implemented to run on any workstation using the architecture neutral Java programming language.  相似文献   
104.
为建立鸭乙型肝炎病毒LJ-76的转染细胞系,将LJ-76病毒DNA插入到pUC19的EcoRⅠ位点上,分离得到含有双拷贝LJ-76DNA的重组质粒.通过磷酸钙沉淀方法,将经CsCl等密度离心纯化的LJ-76DNA双体导入到人肝癌细胞BEL7402中.收集转染细胞的培养液进行蔗糖密度梯度离心,所得沉淀经检测发现含有LJ-76DNA并具有特异性DHBV内源性DNA多聚酶活性;对上述样品通过DotEIA检测DHBV核心抗原及表面抗原结果为阳性.Southernblot分析表明转染细胞内存在病毒DNA复制中间体cccDNA、ssDNA和rcDNA,而cccDNA被认为是复制活动较为活跃的标志.电镜观察转染细胞的上清发现有病毒颗粒的存在.  相似文献   
105.
In this commentary I aim to raise awareness among researchers and sanctuary directors to potential barriers to retiring Old and New World monkeys from research facilities. I define a barrier as an opinion or stereotype that prevents primate retirement from occurring on a regular basis. By discussing retirement barriers and recommending how to overcome them, I aim to increase the frequency of retiring monkeys from the laboratory into naturalistic sanctuaries. In this article I compile a final list of 10 barriers to retirement—and recommendations on how to overcome them—based on responses to forums, comments from primate sanctuary directors, information contained in scientific and sanctuary literature, and personal experiences. I conclude that researchers will increase the frequency of primate retirement by performing the following 5 actions: (a) increase communication by networking with sanctuaries, (b) prevent negative publicity by developing a confidentiality clause with the sanctuary, (c) increase understanding by reviewing the articles written on retiring monkeys into sanctuaries, (d) increase funding for primate retirement by including funding requests in grant proposals, or (e) by raising private funds.  相似文献   
106.
The effects of polyethylene glycol (PEG) on protein structure and the molecular details that regulate its association to polypeptides are largely unknown. These issues were addressed using type I soluble tumor necrosis factor receptor (sTNF-RI) as a model system. Changes in solution viscosity established that a truncated form of sTNF-RI bound free PEG in a pH-dependent manner. Above pH 5.3, the viscosity escalated as the pH increased, while no effect occurred below pH 5.0. Conjugation of 2 kD, 5 kD, or 20 kD PEG to the N terminus attenuated the viscosity at the higher pH values. Tryptophan phosphorescence spectroscopy correlated changes in the protein structure about Trp-107, at the C terminus, with the pH-dependent and PEGylation-dependent attenuation of the viscosity. The results indicate that specific interactions between PEG and the truncated form of sTNF-RI are elicited by an increased flexibility of the truncated protein combined perhaps with removal of steric or charge barriers. Covalently bound PEG at the N terminus reduced the protein affinity for the free polymer and induced a more rigid and polar configuration around Trp-107. Deprotonation of His-105, which is perpendicular to Trp-107, was integral to the binding mechanism producing a pH-dependent switching mechanism. These findings stress the importance of surface charge and structural plasticity in determining macromolecular binding affinities and demonstrate the ability of conjugated PEG to modify the localized surface structure in proteins away from the site of conjugation.  相似文献   
107.
108.
Intracellular calcium buffering capacity in isolated squid axons   总被引:5,自引:7,他引:5       下载免费PDF全文
Changes in ionized calcium were studied in axons isolated from living squid by measuring absorbance of the Ca binding dye Arsenazo III using multiwavelength differential absorption spectroscopy. Absorption changes measured in situ were calibrated in vitro with media of ionic composition similar to axoplasm containing CaEGTA buffers. Calcium loads of 50-2,500 μmol/kg axoplasm were induced by microinjection, by stimulation in 112 mM Ca seawater, or by soaking in choline saline with 1-10 mM Ca. Over this range of calcium loading of intact axoplasm, the ionized calcium in the axoplasm rose about 0.6 nM/μM load. Similar loading in axons preteated with carbonyl cyanide 4- trifluoromethoxyphenylhydrazone (FCCP) to inhibit the mitochondrial proton gradient increased ionized calcium by 5-7 percent of the imposed load, i.e. 93-95 percent of the calcium load was buffered by a process insensitive to FCCP. This FCCP- insensitive buffer system was not saturated by the largest calcium loads imposed, indicating a capacity of at least several millimolar. Treatment of previously loaded axons with FCCP or apyrase plus cyanide produced rises in ionized calcium which could be correlated with the extent of the load. Analysis of results indicated that, whereas only 6 percent of the endogenous calcium in fresh axons is stored in the FCCP-sensitive (presumably mitochondrial) buffer system, about 30 percent of an imposed exogenous load in the range of 50-2,500 μM is taken up by this system.  相似文献   
109.
Matrix metalloproteinase-9 is elevated within the acutely injured murine spinal cord and blockade of this early proteolytic activity with GM6001, a broad-spectrum matrix metalloproteinase inhibitor, results in improved recovery after spinal cord injury. As matrix metalloproteinase-9 is likewise acutely elevated in dogs with naturally occurring spinal cord injuries, we evaluated efficacy of GM6001 solubilized in dimethyl sulfoxide in this second species. Safety and pharmacokinetic studies were conducted in naïve dogs. After confirming safety, subsequent pharmacokinetic analyses demonstrated that a 100 mg/kg subcutaneous dose of GM6001 resulted in plasma concentrations that peaked shortly after administration and were sustained for at least 4 days at levels that produced robust in vitro inhibition of matrix metalloproteinase-9. A randomized, blinded, placebo-controlled study was then conducted to assess efficacy of GM6001 given within 48 hours of spinal cord injury. Dogs were enrolled in 3 groups: GM6001 dissolved in dimethyl sulfoxide (n = 35), dimethyl sulfoxide (n = 37), or saline (n = 41). Matrix metalloproteinase activity was increased in the serum of injured dogs and GM6001 reduced this serum protease activity compared to the other two groups. To assess recovery, dogs were a priori stratified into a severely injured group and a mild-to-moderate injured group, using a Modified Frankel Scale. The Texas Spinal Cord Injury Score was then used to assess long-term motor/sensory function. In dogs with severe spinal cord injuries, those treated with saline had a mean motor score of 2 (95% CI 0–4.0) that was significantly (P<0.05; generalized linear model) less than the estimated mean motor score for dogs receiving dimethyl sulfoxide (mean, 5; 95% CI 2.0–8.0) or GM6001 (mean, 5; 95% CI 2.0–8.0). As there was no independent effect of GM6001, we attribute improved neurological outcomes to dimethyl sulfoxide, a pleotropic agent that may target diverse secondary pathogenic events that emerge in the acutely injured cord.  相似文献   
110.
An inexpensive and quick deoxygenation system for measuring protein phosphorescence is described. Oxygen was first reduced to less than 1 ppb from nitrogen or other inert gas by passing through an oxygen trap. The oxygen-free gas was routed through stainless steel tubing directly into the sample compartment of the phosphorimeter. Flexible tubing, coupled to the stainless steel tubing, was run through the septum of a cuvette sealed with a gray butyl rubber lyophilization stopper. The flexible tubing allowed for manipulation of the cuvette during alternate cycles of vacuuming and nitrogen equilibration. Utility of the system was demonstrated by measuring the phosphorescence lifetimes of N-acetyl-L-tryptophanamide, alkaline phosphatase, human serum albumin, and recombinant human serum albumin. Phosphorescence lifetimes of 2 ms for N-acetyl-L-tryptophanamide, almost double that previously reported, were routinely achieved while a lifetime of 1.84 s was obtained for alkaline phosphatase, well within the reported range of 1.5-2s. Human serum albumin, which contains a single tryptophan, showed a biexponential decay with lifetimes of 4.33 and 17 ms, in contrast to previous reports of a biexponential decay with rates of 0.2 and 0.9 ms. Recombinant human serum albumin was even more striking with lifetimes of 4.60 and 68.2 ms. The data are explained based on the recently published X-ray crystallographic structure of human serum albumin. The simplicity and reproducibility of the system should make this technique practical for most biochemical labs.  相似文献   
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