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61.
Summary The occurrence of testosterone, estrone, and estradiol-17 in aqueous humor and vitreous body of the rabbit eye was demonstrated. The identity of the steroid hormones was confirmed by their chromatographic properties, microreactions, and radiochemically by crystallization to constant specific activity of their labeled acetates. The levels of testosterone and estrogens in rabbit male and female plasma, aqueous, and vitreous were determined by radioimmunologic assay. The concentrations of the steroid hormones in plasma are higher than in aqueous and vitreous. However, testosterone in aqueous circulates in free form and lacks the binding to sexual hormone-binding globulin as in plasma.
Zusammenfassung Bericht über das Vorkommen von Testosteron, Oestron und Oestradiol-17 im Kammerwasser und Glasörper des Kaninchenauges. Die Art der Steroide wurde mittels Chromatographie, Mikroreaktionen und radiochemisch ermittelt. Der Testosteron- und Oestrogenspiegel im männlichen und weiblichen Kaninchenplasma, im Kammerwasser und Glaskörper wurde radioimmunologisch bestimmt. Die Plasmakonzentration der Steroidhormone lag höher als diejenige im Kammerwasser oder Glaskörper. Testosteron zirkuliert jedoch im Kammerwasser in freier Form, im Plasma dagegen ist es überwiegend an Sexualhormonebindende Globuline gebunden.
  相似文献   
62.
The aim of the study was to determine whether and to what extent changes in the electrocardiograms occurred in released prisoners of war (POWs) from Serbian detention camps and whether the frequency of occurrence differed from similar changes in a control group. An electrocardiogram was recorded and medical examinations conducted on 182 randomly selected ex-POWs. The subjects were male with a mean age of 35.8 ± 11.0 years, age range 18–65 years and the average length of imprisonment 164.5 ± 87.1 days. The electrocardiograms were analysed according to the Minnesota côde. The following changes were frequently found: postinfarction Q-wave in 3.3%, control 1.1% (not significant), ST-segment depression horizontal or descendent in 14.3% (controls 3.8%, P < 0.01), particularly S-T segment depression of up to 0.5 mm in 12.1% (controls 2.2%, (P < 0.01), total negative T-wave in 7.1% (control group 3.3%, not significant), total arrhythmia 18.1% (controls 7.1%, P < 0.01), particularly ventricular premature beats in 2.2% (controls 0.5%, not significant), incomplete left bundle-branch block 2.2% (not registered in the control group), complete left bundle-branch block in 0.5% (not registered in the control group), sinus tachycardia in 12.1% (controls 6.6%, not significant), sinus bradycardia 3.3% (not registered in the control group) and microvoltage QRS complex in 11.5% (controls 0.5%, P < 0.001). The results of this study confirm that changes in the electrocardiograms of the POWs released from Serbian detention camps were far more frequent than in the controls.  相似文献   
63.
BackgroundGastroesophageal reflux disease has a high incidence of 23%, with 29% of those with gastroesophageal reflux disease consuming nonsteroidal anti-inflammatory drugs. There are insufficient data concerning the effects of nonsteroidal anti-inflammatory drugs on the esophageal tissue. We aimed to examine the effects of well-known nonsteroidal anti-inflammatory drugs using electrophysiologic criteria on the rabbit esophageal epithelium.MethodsEsophageal epithelium mounted on Ussing chambers enabled in vitro investigation of the electrophysiological properties. Doses of 1 mg/mL, 2.5 mg/mL, 5 mg/mL ibuprofen, naproxen, and aspirin were dissolved in dimethyl sulfoxide and added to the luminal side. Esophagi were cannulated from both sides for the administration of high-dose ibuprofen in vivo, and the potential difference was monitored.ResultsIbuprofen and aspirin inhibited tissue transport functions in a dose-dependent manner. pH 4 acid and 0.1 mg/mL ibuprofen alone were not harmful; however, the combination of these agents had an additive and significance effect: 78% decrease in the potential difference and 85% decrease in the short-circuited current (Isc). The change in the potential difference in the in vivo experiments (5 mg/mL ibuprofen) was similar (52 ± 7% decrease) with in vitro experiments in the first 30 minutes.ConclusionNonsteroidal anti-inflammatory drugs were harmful to the rabbit esophageal epithelium in both the in vitro and in vivo experiments. Even though aspirin and ibuprofen affected the transport mechanisms of the esophageal epithelium, the dose-dependent decrease of tissue potential difference and Isc with ibuprofen was more pronounced than those with aspirin. The combination of harmless doses of ibuprofen and acid demonstrated that even low acidic conditions can create a disruptive environment.  相似文献   
64.
This study aimed to investigate the influence of silicone oil on the retinal nerve fiber layer (RNFL) thickness in patients with primary rhegmatogenous retinal detachment who underwent vitreoretinal surgery. The study included 47 patients (eyes), who underwent a pars plana vitrectomy with the silicone oil tamponade. The control group included unoperated eye of all participants. Spectral-domain optical coherence tomography (SD-OCT) was used for the measurements of peripapilar and macular RNFL thickness. The average peripapillary RNFL thickness was significantly higher in the silicone oil filled eyes during endotamponade and after its removal. The eyes with elevated IOP had less thickening of the RNFL in comparison to the eyes with normal IOP. Central macular thickness and macular volume were decreased in the silicone oil filled eyes in comparison to the control eyes. In conclusion, silicone oil caused peripapilar RNFL thickening in the vitrectomized eyes during endotamponade and after silicone oil removal.  相似文献   
65.
Dietary supplements used by women during menopause are usually based on plant extracts containing isoflavonoids, daidzein and genistein. Genistein is a known inhibitor of many enzymes, including thyroid peroxidase (TPO). In the thyroid follicle, genistein acts as its alternate substrate for the formation of genistein iodinated derivatives. The aim of this study was to search for daidzein- and genistein-iodinated derivatives in urine of isoflavonoid-supplemented women. Additionally, selected phytoestrogens, steroid and thyroid hormones before and after three months of phytoestrogen supplementation were estimated. Urinary levels of free phytoestrogen increased significantly after therapy. They ranged between 0.3–1600, 0.6–670 and 0–206 nmol/L for daidzein, genistein and S-equol, respectively. Monoiodinated derivatives of genistein were observed (0–504 pmol/L) in 60% of the investigated samples. Steroid and thyroid hormone levels were within the normal range and were not significantly altered. The presence of monoiodinated derivates in human urine confirmed that genistein and daidzein may enter human thyroid follicles and influence TPO. Since the levels of the free thyroid hormones were not affected, we propose that the use of phytoestrogen dietary supplements is not associated with the development of thyroid-gland disorders in subjects with adequate iodine intake.  相似文献   
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Imaging of blood vessel structure in combination with functional information about blood oxygenation can be important in characterizing many different health conditions in which the growth of new vessels contributes to the overall condition. In this paper, we present a method for extracting comprehensive maps of the vasculature from hyperspectral images that include tissue and vascular oxygenation. We also show results from a preclinical study of peritonitis in mice. First, we analyze hyperspectral images using Beer-Lambert exponential attenuation law to obtain maps of hemoglobin species throughout the sample. We then use an automatic segmentation algorithm to extract blood vessels from the hemoglobin map and combine them into a vascular structure-oxygenation map. We apply this methodology to a series of hyperspectral images of the abdominal wall of mice with and without induced peritonitis. Peritonitis is an inflammation of peritoneum that leads, if untreated, to complications such as peritoneal sclerosis and even death. Characteristic inflammatory response can also be accompanied by changes in vasculature, such as neoangiogenesis. We demonstrate a potential application of the proposed segmentation and processing method by introducing an abnormal tissue fraction metric that quantifies the amount of tissue that deviates from the average values of healthy controls. It is shown that the proposed metric successfully discriminates between healthy control subjects and model subjects with induced peritonitis and has a high statistical significance.  相似文献   
70.
Tuberculosis is still one of the major global public health threats. Countries with low incidence must focus on exhausting the reservoir of future cases by preventing reactivation. Therefore, it is important to identify and effectively treat those individuals who have latent tuberculosis infection and who may develop active disease. The tuberculin skin test has been the standard for detection of immune response against M. tuberculosis since the beginning of the 20th century. The new millennium has brought advancement in the diagnosis of latent tuberculosis infection. The name of the new blood test is interferon-gamma release assay (IGRA). Croatia is a middle-incidence country with a long decreasing trend and developed tuberculosis control. To reach low incidence and finally eliminate tuberculosis, its tuberculosis programme needs a more aggressive approach that would include intensive contact investigation and treatment of persons with latent tuberculosis infection. This article discusses the current uses of IGRA and its role in tuberculosis control.  相似文献   
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