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91.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, broke out in December 2019 in Wuhan city of China and spread rapidly worldwide. Therefore, by March 2020, the World Health Organization declared the disease a global pandemic. Apart from the respiratory system, various other organs of the human body are also seriously affected by the virus. Liver injury in patients with a severe form of COVID-19 is estimated to be 14.8%-53.0%. Elevated levels of total bilirubin, aspartate aminotransferase and alanine aminotransferase and low levels of serum albumin and prealbumin are the main laboratory findings. Patients with pre-existing chronic liver disease and cirrhosis are much more prone to develop severe liver injury. This literature review presented the recent scientific findings regarding the pathophysiological mechanisms responsible for liver injury in critically ill patients with COVID-19, the various interactions between drugs used to treat the disease and the function of the liver and the specific tests providing the possibility of early diagnosis of severe liver injury in these patients. Moreover, it highlighted the burden that COVID-19 put on health systems worldwide and its effect on transplant programs and the care provided to critically ill patients in general and particularly to those with chronic liver disease.  相似文献   
92.
The atmospheric deposition of Al, Cr, Fe, Ni, V, and Zn in Albania was investigated by using carpet-forming moss species (Hypnum cupressiforme) as bioindicators. This research is a part of the international program (International Cooperative Programme (ICP) Vegetation, UNECE) carried out in most European countries since 1987, investigating the impacts of air pollutants on crops and natural vegetation. Sampling was carried out during the dry seasons of autumn 2010 and summer 2011 at 62 sites distributed all over Albania. Unwashed, dried samples were totally digested by using microwave digestion, and the concentrations of metal elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results reflect local emission points. Only the elements with high values of concentration, Al, Cr, Fe, Ni, V, and Zn, compared to other European countries are discussed in this paper. The median values of chromium (4.75 mg/kg, dry weight (DW)), iron (1,618 mg/kg, DW), nickel (5.85 mg/kg, DW), vanadium (3.51 mg/kg, DW), zinc (13.77 mg/kg, DW), and aluminum (6,974 mg/kg, DW) are similar to those of neighboring countries but higher than those of European countries. An exponentially weighted moving average (EWMA) and univariate control chart was used to investigate the moving range of successive observations and to estimate the variability of the data. Certain local emitters were identified like the iron-chromium metallurgy and cement industry, oil refinery, mining industry, and transport. In addition, natural sources, such as the accumulation of these metals in mosses caused by metal-enriched soils, associated with the wind blowing soils particularly in the southeast direction of the country, were pointed as another local emitting factor.  相似文献   
93.
Heart Failure Reviews - Heart failure (HF) and atrial fibrillation (AF) often coexist, being closely interrelated as the one increases the prevalence and incidence and worsens the prognosis of the...  相似文献   
94.
95.
Most, if not all, cancers are composed of cells in which more than one gene has a cancer-promoting mutation. Although recent evidence has shown the benefits of therapies targeting a single mutant protein, little attention has been given to situations in which experimental tumors are induced by multiple cooperating oncogenes. Using combinations of doxycycline-inducible and constitutive Myc and mutant Kras transgenes expressed in mouse mammary glands, we show that tumors induced by the cooperative actions of two oncogenes remain dependent on the activity of a single oncogene. Deinduction of either oncogene individually, or both oncogenes simultaneously, led to partial or complete tumor regression. Prolonged remission followed deinduction of Kras(G12D) in the context of continued Myc expression, deinduction of a MYC transgene with continued expression of mutant Kras produced modest effects on life extension, whereas simultaneous deinduction of both MYC and Kras(G12D) transgenes further improved survival. Disease relapse after deinduction of both oncogenes was associated with reactivation of both oncogenic transgenes in all recurrent tumors, often in conjunction with secondary somatic mutations in the tetracycline transactivator transgene, MMTV-rtTA, rendering gene expression doxycycline-independent. These results demonstrate that tumor viability is maintained by each gene in a combination of oncogenes and that targeted approaches will also benefit from combination therapies.  相似文献   
96.
Introduction: Patients with persistent atrial fibrillation (AF) have hemodynamic changes, which impair endothelial cell function resulting in decreased nitric oxide (NO) production. The aim of this work was to assess endothelial function in AF patients before and at various time points after cardioversion. Methods: Forty-two patients with AF and 21 normal and age-adjusted healthy controls were studied. Nitrites and nitrates (NO x ) and von Willebrand factor (vWf) concentrations were measured on blood samples taken just before cardioversion and over a 30 day period after the procedure. Results: Plasma levels of NO x in AF were significantly lower compared to healthy controls (p < 0.001), but after cardioversion gradually increased to approach to those of the healthy controls by the end of the first month of sustained sinus rhythm (p = 0.004). Interestingly plasma levels of NO x were negatively correlated to left atrial volume measured by ultrasonography (r = –0.34, p < 0.05). Plasma levels of vWf in AF patients were significantly higher compared to the healthy controls (p < 0.01) but with sustained sinus rhythm decreased (p = 0.02). Conclusion: The parallel normalization of the NO x titers and vWf levels suggests that vascular endothelial function improves after 30 days of normal sinus rhythm.  相似文献   
97.
BACKGROUND: Gastrocutaneous fistula is an uncommon and difficult to treat complication that occurs in 0.5% to 3.9% of patients who undergo gastric surgery. Sepsis usually follows, and, when it is not managed effectively, the associated mortality rate can be as high as 85%. A fibrin sealant was used to endoscopically manage gastrocutaneous fistulas that developed in 3 morbidly obese patients after bariatric surgery. METHODS: Two of 14 (14.29%) patients who underwent vertical gastroplasty (MacLean procedure) developed a non-healing gastrocutaneous fistula. In addition, one of 24 (4.17%) patients who had a biliopancreatic diversion with preservation of pylorus developed a gastrocutaneous fistula. Endoscopic application of a fibrin sealant was performed under direct vision via a double-lumen catheter passed through a forward-viewing endoscope. OBSERVATIONS: Treatment was successful in all patients after one or more endoscopic sessions in which the fibrin sealant was applied; no evidence of fistula was found at follow-up endoscopy. CONCLUSIONS: Endoscopic closure of gastrocutaneous fistula with human fibrin tissue sealant is simple, safe, and effective, and, in some cases, can be life-saving. Endoscopic application of fibrin sealant should be considered a therapeutic option for treatment of gastrocutaneous fistula that develops after bariatric surgery.  相似文献   
98.
A 72-year-old patient with liver cirrhosis and cavernomatous portal vein occlusion presented with refractory ascites. We treated the patient with transjugular intrahepatic portosystemic shunt: transjugular transhepatic puncture of an intrahepatic hilar collateral vein was performed; transjugular intrahepatic portosystemic shunt was created between the right hepatic vein and the patent superior mesenteric vein using this hilar collateral vein as the connecting pathway. The ascites was resolved and the patient remains asymptomatic, while shunt patency is maintained 16 months after the intervention.  相似文献   
99.
BACKGROUND: Tea consumption is associated with decreased cardiovascular risk. Flow-mediated dilatation (FMD) of the brachial artery is related to coronary endothelial function and it is an independent predictor of cardiovascular risk. Black tea has a beneficial effect on endothelial function; the effect, however, of green tea on brachial artery reactivity has not been defined yet. DESIGN AND METHODS: We studied 14 healthy individuals (age 30+/-3 years) with no cardiovascular risk factors except from smoking (50%) on three separate occasions on which they took: (a) 6 g of green tea, (b) 125 mg of caffeine (the amount contained in 6 g of tea), or (c) hot water. FMD of the brachial artery was measured before each intervention and 30, 90, and 120 min afterward. High-sensitivity C-reactive protein, interleukins 6 (Il-6) and 1b (Il-1b), total plasma antioxidative capacity, and total plasma oxidative status/stress were measured at baseline and at 120 min after each intervention. RESULTS: Resting and hyperemic brachial artery diameter did not change either with tea or with caffeine. FMD increased significantly with tea (by 3.69%, peak at 30 min, P<0.02), whereas it did not change significantly with caffeine (increase by 1.72%, peak at 30 min, P=NS). Neither tea nor caffeine had any effect on high-sensitivity C-reactive protein, Il-6, Il-1b, total plasma antioxidative capacity, or total plasma oxidative status/stress. CONCLUSION: Green tea consumption has an acute beneficial effect on endothelial function, assessed with FMD of the brachial artery, in healthy individuals. This may be involved in the beneficial effect of tea on cardiovascular risk.  相似文献   
100.
The aim of this study was to examine the effect of aerobic exercise training on insulin sensitivity in overweight and obese girls. Nineteen overweight and obese girls (mean +/- SD: age, 13.1+/-1.8 years; body mass index, 26.8+/-3.9 kg/m(2)) volunteered for this study. Body composition (dual-energy x-ray absorptiometry), insulin sensitivity (oral glucose tolerance test and homeostasis model assessment estimate of insulin resistance; n=15), adiponectin, C-reactive protein (CRP), interleukin (IL) 6, insulin-like growth factor-1, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 serum levels, and blood lipids and lipoproteins were assessed before and after 12 weeks of aerobic training. Cardiorespiratory fitness increased by 18.8% (P<.05) as a result of training. The area under the insulin concentration curve (insulin area under the curve) decreased by 23.3% (12781.7+/-7454.2 vs 9799.0+/-4918.6 microU.min/mL before and after intervention, respectively; P=.03). Insulin sensitivity was improved without changes in body weight (pre-intervention, 67.9+/-14.5 kg; post-intervention, 68.3+/-14.0 kg) or percent body fat (pre-intervention, 41.4% +/- 4.8%; post-intervention, 40.7%+/-5.2%). The lower limb fat-free mass increased by 6.2% (P<.01) as a result of training, and changes in lower limb fat-free mass were correlated with changes in the insulin area under the curve (r= -.68; P< .01). Serum adiponectin, IL-6, and CRP concentrations did not change (pre-intervention vs post-intervention: adiponectin, 9.57+/-3.01 vs 9.08+/-2.32 microg/mL; IL-6, 1.67+/-1.29 vs 1.65+/-1.25 pg/mL, CRP, 3.21+/-2.48 vs 2.73+/-1.88 mg/L) whereas insulin-like growth factor-1 was lower after training (pre-intervention, 453.8 +/- 159.3 ng/mL; post-intervention, 403.2+/- 155.1 ng/mL; P<.05). In conclusion, 12 weeks of aerobic training improved insulin sensitivity in overweight and obese girls without change in body weight, percent body fat, and circulating concentrations of adiponectin, IL-6, CRP, and other inflammatory markers. These findings suggest that increased physical activity may ameliorate the metabolic abnormalities associated with obesity in children with a mechanism other than the parameters cited earlier.  相似文献   
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