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101.
102.
PURPOSE: Recent evidence suggests that sex steroids may produce rapid inhibition of voltage operated Ca2+ channels (VOCCs). Detrusor smooth muscle is highly dependent upon Ca2+ influx for receptor-activated contractions. Thus, we examined the relative effectiveness of a select group of sex steroids and dietary phytoestrogens to relax detrusor contracted with the muscarinic receptor agonist, bethanechol (BE) and the purinergic P2X receptor agonist, alpha,beta-methylene ATP (alpha,beta-MeATP). MATERIALS AND METHODS: Isolated strips of rabbit detrusor were secured to isometric force transducers in a tissue bath and length-adjusted until maximum contractions were achieved. Peak (P) contractile responses were recorded for alpha,beta-MeATP (P(ATP)) and BE (P(BE)) and steady-state (SS) responses were recorded for BE (SS(BE)) in the presence and absence of selected sex steroids and phytoestrogens (10 microM, unless indicated). RESULTS: The L-type VOCC inhibitor, nifedipine (1 to 10 microM), completely inhibited P(ATP) but reduced SS(BE) by approximately 50%, whereas the VOCC and non-VOCC inhibitor, SKF 96365, inhibited SS(BE) by approximately 95%, suggesting that P(ATP) was entirely dependent on L-type VOCCs, but (BE)-induced contractions depended also on activation of non-VOCCs. 17Beta-estradiol (estradiol) and progesterone inhibited P(ATP) by approximately 60% and 20%, respectively, and 32 microM estradiol and ethinyl estradiol inhibited SS(BE) by approximately 80 and 95%, respectively. Inhibition by estradiol was potentiated, rather than blocked, by the nuclear estrogen receptor antagonist, tamoxifen. Moreover, tamoxifen alone nearly completely relaxed SS(BE). The inactive metabolite of estradiol, 17alpha-estradiol, inhibited both P(ATP) and P(BE) by approximately 40%. Testosterone had no effect on P(ATP) and P(BE). The phytoestrogen and tyrosine kinase inhibitor, genistein, inhibited SS(BE) by 44%, whereas daidzein, a phytoestrogen without tyrosine kinase inhibitory activity, produced only a 7% inhibition. None of the phytoestrogens examined inhibited P(BE), whereas all inhibited P(ATP) by approximately 20 to 35%. A comparison of inhibition of (BE) and alpha,beta-MeATP-induced contractions by selected estrogen isomers showed some distinct differences. For example, estrone did not inhibit P(BE) or SS(BE), but inhibited P(ATP) by approximately 20%, whereas DES inhibited SS(BE) by nearly 90%, but P(ATP) by a lesser degree (approximately 70%). CONCLUSIONS: Our data support the hypothesis that 17beta-estradiol, ethinyl estradiol, DES, tamoxifen and genistein may relax detrusor contractions by inhibition of both VOCCs and non-VOCCs. Moreover, our data show that genistein, a dietary phytoestrogen with tyrosine kinase inhibitory activity, selectively reduced alpha,beta-MeATP-induced peak and BE-induced steady-state contractions, sparing the maximum response to BE. Lastly, the inactive isomer, 17alpha-estradiol, inhibited both BE- and alpha,beta-MeATP-induced contractions. These data suggest that certain dietary phytoestrogens (for example, genistein) or sex steroids, especially those with weak activity at the nuclear steroid site (for example, 17alpha-estradiol), or tamoxifen may prove therapeutically useful in treating overactive bladder caused by elevated muscarinic and purinergic receptor activation.  相似文献   
103.
Atrial Fibrillation and Embolic Complications in Paced Patients   总被引:5,自引:0,他引:5  
Atrial fibrillation (AF) and thromboembolism are discussed to he complications of the WI mode. We reinvestigated the spontaneous ECG and the anamnesis of 246 pacemaker patients with the indications second and third degree atrioventricular block (AV block, n = III), sick sinus syndrome (SSS, n - 101) and other indications (n = 34), all had shown sinus rhythm at implantation. The mean implantation time was 63 ± 45 months (203 VVI and 43 dual chamber pacemkers). The results: (1) Atrial fibrillation was found in 63 patients (26%). Only one of them had a DDD pacemaker inserted, the implantation time of dual chamber devices being shorter, however, (2) The incidence of AF in patients with SSS (37%) was significantly higher (P < 0.01) than in patients with AV block (19%). (3) Three patients suffered from strokes or transitory ischemic attacks in the follow-up, only one of them had AF at control. Conclusions: Our results confirm that VVI stimulation favors AF long-term which is most likely due to irritation of the atrial rhythm by retrograde conduction. In our patients the incidence of thromboembolic complications was not higher in the group of patients with AF. However, from this study in surviving patients, we cannot exclude that we Jost some patients due to severe stroke.  相似文献   
104.
BACKGROUND: Sandifer Syndrome is an uncommon clinical entity characterized by gastroesophageal reflux, irritability and abnormal movements of the body and contortions of the neck. The majority of paroxysmal cases, in particular, tend to show an association with epilepsy. METHODS: The clinical, laboratory and 6-month observation results of the four patients (two boys, two girls) have been presented. RESULTS: The 6-month prospective observation/treatment of four patients aged between 2 and 14 months (mean age, 6.5 +/- 5.2 months) with a diagnosis of Sandifer Syndrome has been investigated. Due to paroxysmal extensor jerks, two of the patients were misdiagnosed with infantile spasm and they were treated accordingly. In the clinical observations of the patients, abnormal neurobehavioral attacks (irritability, crying, head/eye version, torticollis, extensor spasm and dystonic posture) 5-10 times daily were observed. In two of the patients, motor growth retardation was observed, in one patient, bronchospasm attacks were observed, and in all the patients iron deficiency anemia was observed. The electroencephalograms of the patients which were taken during the routine, sleepless and paroxysmal behaviors were normal; the gastroesophageal scintigraphies were positive in the manner of reflux. Management of the infant with gastroesophageal reflux disease, in addition to nonpharmacological interventions pharmacologic therapy, including metoclopramide HCl and Fe (6 mg/kg per day, oral) was useful for the patients, and their paroxysmal attacks decreased dramatically (0-2 attacks/day). CONCLUSION: These findings suggest that infants or children with these atypical movements should be evaluated for Sandifer Syndrome. Expensive and comprehensive neurologic examination may be unnecessary. Early diagnosis permits prompt treatment and relief of the problem. Medical management is usually successful.  相似文献   
105.
A method to identify and accurately measure non-labelled Δ1-tetrahydrocannabinol (Δ1-THC) in blood of cannabis smokers has been developed. It consists of the following steps: To a 5 ml plasma sample is added deuterated Δ1-THC (Δ1-THC-d2) as internal standard. After extraction with light petroleum and evaporation, the Δ1-THC containing fraction is separated by chromatography on Sephadex LH-20 (1 times 40 cm) using light petroleum-chloroform-ethanol (10:10:1) as eluant. A fraction containing Δ1-THC is collected and subjected to mass fragmentography (LKB 9000; 3% OV-17/Gas-Chrom Q; 230°). The mass spectrometer was adjusted to record the intensities of m/e 299 and 314 of Δ1-THC and m/e 301 and 316 of Δ1-THC-d2. The standard curve was made by plotting peak height m/e 299/m/e 301. Peak levels of 19–26 ng ml?1 were reached within 10 min after smoking a cigarette containing 10 mg Δ1-THC.  相似文献   
106.
T cells from patients with active lupus have multiple biochemical abnormalities. One of these is DNA hypomethylation, which in model systems alters gene expression and induces lupus-like autoimmunity. Recent reports indicate that DNA methylation is regulated in part by the ERK pathway, and that ERK pathway signaling is diminished in lupus T cells. This suggests a model in which defective T cell ERK pathway signaling contributes to the development of autoimmunity by decreasing DNA methyltransferase expression, modifying DNA methylation patterns and altering gene expression. This mechanism could contribute to idiopathic and drug-induced lupus.  相似文献   
107.

Background

Cutaneous leishmaniasis (CL) is endemic in Southeastern Anatolia, mainly in Sanliurfa and Hatay provinces, and the causative agents are mostly Leishmania tropica and less frequently L. infantum. Here, we report the first MALDI-TOF analyses of Leishmania promastigotes obtained from the cultures of two CL cases from Osmaniye and Hatay provinces who were initially diagnosed by microscopy, culture and identified as L. infantum with Real-Time PCR (RT-PCR).

Methods

Samples obtained from the skin lesions of patients were initially stained with Giemsa and cultivated in NNN medium. Examination of the smears and cultures revealed Leishmania amastigotes and promastigotes, respectively. The promastigotes (MHOM/TR/2012/CBU15 and MHOM/TR/2012/MK05) obtained from the cultures of both patients were used for RT-PCR targeting the ITS-1 region in the SSU of rRNA. The reference strains of four Leishmania species (L. infantum, L. donovani, L. tropica and L. major) were initially assessed with MALDI-TOF and their data were added to MALDI-TOF Biotyper Library.

Results

Both RT-PCR and MALDI-TOF analyses indicated that the causative agent in both patient samples was L. infantum.

Conclusion

Despite disadvantages such as requirement of culture fluid with nothing but promastigotes and high cost, MALDI-TOF analysis may be a fast, sensitive and specific diagnostic tool in especially large-scale research studies, where the cost declines, relatively.  相似文献   
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