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1.
Summary The participation of substance P in the noncholinergic contraction induced by transmural stimulation (TMS) of the carp intestinal bulb was examined. In the presence of atropine, substance P caused the contraction of carp intestinal bulb smooth muscle in a concentration dependent manner (1 nmol/1 – 1 mol/l). The EC50 value was 28 ± 7 nmol/l (n = 6). Substance P-induced desensitization (1 mol/l for 15 min), decreased the response to substance P and the atropine-resistant contraction induced by TMS (20 Hz) selectively. In contrast, in the absence of atropine, the contraction induced by TMS (20 Hz) was slightly attenuated with the substance P-induced desensitization. The acid extract obtained from the carp intestinal bulb contained a smooth muscle excitatory material whose pharmacological properties were consistent with those of substance P. The present results indicate that a substance P-like peptide is present in the carp intestinal bulb which is involved in the non-cholinergic contraction induced by TMS.Send offprint requests to T. Kitazawa at the above address  相似文献   
2.
Poly(vinyl alcohol) (PVA) was coated onto polyethylene (PE) films by a repetitive adsorption and drying process, and then the PVA-coated PE films were alternately immersed into aqueous solutions of Ca2+ and CO3(2-) ions (alternate soaking cycles), to deposit calcium carbonate (CaCO3) onto the films. The PVA coating was essential for the CaCO3 deposition. The amount of CaCO3 deposited increased with an increasing number of cycles. Scanning electron microscopic observations and attenuated total reflection spectra revealed the presence of both calcite and aragonite as the crystal structures of CaCO3 on the film. L929 fibroblast cells adhered and proliferated on these CaCO3-deposited PE films, as well as the hydroxyapatite-coated PE films previously prepared. It was found that the PVA coating and the subsequent deposition of calcium salts on certain films facilitated cell compatibility.  相似文献   
3.
Clinical and genomic features of prostate cancer (PCa) vary considerably between Asian and Western populations. PTEN loss is the most frequent abnormality in intraductal carcinoma of the prostate (IDC-P) in Western populations. However, its prevalence and significance in Asian populations have not yet been well studied. In the present study, we evaluated PTEN expression in IDC-P in a Japanese population and its association with ERG expression. This study included 45 and 59 patients with PCa with and without IDC-P, respectively, who underwent radical prostatectomy. PTEN loss was observed in 10 patients with PCa with IDC-P (22%) and nine patients with PCa without IDC-P (17%). ERG expression was relatively frequent in patients with PCa with PTEN loss, although a significant difference was not observed. The co-occurrence of PTEN loss and ERG expression was observed in four patients with PCa with IDC-P and one without IDC-P. PTEN loss and ERG expression did not affect progression-free survival, regardless of the presence of IDC-P. The frequency of PTEN loss in IDC-P is lower in Asian patients than in Western patients. Our results indicate that mechanisms underlying IDC-P in Asian populations are different from those of Western populations.  相似文献   
4.
The hypothalamic growth hormone (GH)-releasing hormone (GHRH) promotes non-rapid eye movement sleep (NREMS). Insulin-like growth factor-1 (IGF-1) acts as a negative feedback in the somatotropic axis inhibiting GHRH and stimulating somatostatin. To determine whether this feedback alters sleep, rats and rabbits were injected intracerebroventricularly (i.c.v.) with IGF-1 (5.0 and 0.25 microgram, respectively) and the sleep-wake activity was studied. Compared to baseline (i.c.v. injection of physiological saline), IGF-1 elicited prompt suppressions in both NREMS and rapid eye movement sleep (REMS) in postinjection hour 1 in rats and rabbits. The intensity of NREMS (characterized by the slow wave activity of the EEG by means of fast-Fourier analysis) was significantly enhanced 7 to 11 h postinjection in rats. Plasma GH concentrations were measured in 30-min samples after i.c.v. IGF-1 injection in rats and a significant suppression of GH secretion was observed 30 min postinjection. The simultaneous inhibition of the somatotropic axis and sleep raises the possibility that the sleep alterations also result from an IGF-1-induced suppression of GHRH. The late increases in NREMS intensity are attributed to metabolic actions of IGF-1 or to a release of GHRH from the IGF-1-induced inhibition.  相似文献   
5.
Doxorubicin produced a transient increase and a subsequent decrease in the amplitude of twitch contraction in myocytes isolated from guinea-pig heart and loaded with fura-2. These changes were associated with an increase and a subsequent decrease, respectively, in the amplitude of Ca(2+) transients (peak minus diastolic Ca(2+) concentrations). Doxorubicin increased the diastolic Ca(2+) concentration with a concomitant shortening of the diastolic myocyte length. The time to peak Ca(2+) transients and the time to peak twitch contraction increased in parallel. Doxorubicin failed to affect the Ca(2+) concentration-contraction curve in skinned fibers obtained from atrial muscle. We conclude that biphasic inotropic effects of doxorubicin result from biphasic changes in Ca(2+) transients, and that doxorubicin fails to alter Ca(2+) sensitivity of contractile proteins. These findings are consistent with the hypothesis that doxorubicin enhances Ca(2+) release and impairs Ca(2+) uptake by the sarcoplasmic reticulum.  相似文献   
6.
7.
BackgroundThe purpose of this study was to investigate residual acetabular retroversion after skeletal maturity in patients with Pemberton osteotomy.Patients and methodsWe compared 40 hips in 36 patients treated with a Pemberton osteotomy (Pemberton group) and 30 hips in 26 patients treated only with a Pavlik harness (Rb group) for developmental dysplasia of the hip. The average age at operation in the Pemberton group was 94.5 months and the follow-up duration was 151.8 months. Radiographic parameters included the acetabular index (a angle) and the center-edge angle of Wiberg, preoperatively and at skeletal maturity. We examined the crossover sign (COS) at the latest follow-up as a sign of acetabular retroversion (AR). We compared the parameters between the two groups and examined the risk factors for acetabular retroversion using a multivariate Cox model.ResultA COS (+) was significantly more frequent in the Pemberton group compared to the Rb group [15 hips (37.5 %) vs 3 hips (10 %); p = 0.0077]. In the Pemberton group, the average age at operation in COS (+) hips was significantly older than that in COS (—) hips (126.9 vs 72.8 months; p = 0.0005). The preoperative α angle did not vary between hips with and without COS; however, the postoperative α angle was significantly smaller in COS (+) hips. A multiple logistic regression analysis for prediction of COS (+) showed that the age at operation and the amount change of α angle were significant predictors for COS (+) hips. The cut-off of the age at operation was 7 years and 9 months old.ConclusionsAR was present in 37.5 % of the hips in the Pemberton group after skeletal maturity. Remodeling of acetabular version was observed in younger patients; however, hips in older patients (> 8 years) at the time of operation and greater degrees of correction tended to result in AR.  相似文献   
8.
The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E2, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically.  相似文献   
9.
The requirement for well spread out chromosomes for the cytogenetic analysis of primary gastrointestinal tumors led us to develop new techniques. These techniques involved two main procedures: (1) preliminary incubation with culture medium in the presence of collagenase, Dispase, and colcemid, for 3h, and (2) treatment with an extremely hypotonic solution (0.044 M KCl) for 30 min. The techniques were applied to 11 gastrointestinal malignancies (including 1 early gastric cancer and 1 metastatic liver lesion of colon cancer) and significant increases (P<0.01) in the number of metaphases of analyzable karyotypes were obtained, compared with a previous method in which the standard hypotonic molarity of KCL (0.075 M) was employed. The mean value for metaphase numbers of the analyzable karyotypes was 37.0±3.7% in the 5 gastric cancers and 44.7±4.8% in the 5 colon cancers and 1 metastatic lesion. These values were three times and more than twice, respectively, the values obtained by the previous method. A fluorescence in situ hybridization (FISH) study was carried out on one cologenic tumor, the α-satellite centromere-specific probe 17 being used. Deletion of the long arm of chromosome 17 was demonstrated. The method proposed here could yield a sufficient number of metaphases without the use of tissue culture that might cause alteration of karyotype. It can be employed with small biopsy specimens and in studies utilizing the FISH technique.  相似文献   
10.
To clarify the significance of newly appearing abnormal Q waves and their disappearance in patients with Kawasaki disease, regional myocardial perfusion and glucose metabolism at rest in the fasting condition were assessed by positron emission tomography (PET) with 13N-ammonia and 18F-fluorodeoxyglucose (FDG), and regional wall motion by left ventriculography in regions with persistent and transient abnormal Q waves in 14 patients. PET identified 3 groups of abnormal myocardial segments: segments with hypoperfusion without increased FDG uptake, those with hypoperfusion and increased FDG uptake, and those with normal perfusion and increased FDG uptake. Almost all the segments with persistent or transient abnormal Q waves had abnormal PET findings. PET demonstrated evidence of metabolic activity in 57% of segments with persistent abnormal Q waves and 67% of those with transient abnormal Q waves. Regional wall motion, scored from 0 (normal) to 4 (dyskinesia), was not significantly different between segments with persistent and transient abnormal Q waves (2.3 ± 1.3 vs 2.2 ± 1.2). The persistence of abnormal Q waves on serial electrocardiograms was significantly shorter in metabolically active than in inactive segments (19 ± 17 vs 92 ± 27 months). In conclusion, in patients with Kawasaki disease, the new appearance of abnormal Q waves is a reliable clue to the presence of ischemic myocardial injury and a high proportion of them are associated with metabolically active myocardial regions. The disappearance of abnormal Q waves does not necessarily mean the normalization of regional myocardial perfusion, metabolism or function, and their early disappearance may imply “viability” in the associated myocardial region.  相似文献   
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