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991.
Twenty-one consecutive patients with streptococcal toxic shock syndrome (TSS) between December 1994 and April 1995 were treated with a median dose of 2 g of intravenous immunoglobulin (IVIG)/kg (cases) and were compared with 32 patients with streptococcal TSS between 1992 and 1995 who did not receive IVIG therapy (controls). The outcome measure was 30-day survival. Patient plasma was tested for its ability to inhibit T cell activation induced by the infecting strain. The proportion of cases with 30-day survival was higher than that of the controls with 30-day survival (67% vs. 34%, respectively; P = .02). Multivariate analysis revealed that IVIG administration and a lower Acute Physiology and Chronic Health Evaluation II score were associated with survival; the odds ratio for survival associated with IVIG therapy was 8.1 (95% confidence interval, 1.6-45; P = .009). IVIG therapy enhanced the ability of patient plasma to neutralize bacterial mitogenicity and reduced T cell production of interleukin-6 and tumor necrosis factor alpha. IVIG may be an effective adjunctive therapy for streptococcal TSS, possibly because of its ability to neutralize bacterial exotoxins.  相似文献   
992.
Horizontal and frontal plane QRS loops of patients in sinus rhythm with uniform ventricular extrasystoles were constructed from digitised Frank orthogonal electrocardiogram. In 4 patients ventricular extrasystoles were indistinguishable from right bundle-branch complexes, and in another 4 from left bundle-branch complexes. In 25 patients ventricular extrasystoles showed an initial delay (greater than or equal to 20 msec) of the QRS, followed by an R loop, which in 13 patients resembled LBBB complexes, and 12 patients resembled RBBB complexes with an anterior clockwise loop in the horizontal plane. However, the frontal plane loop was often atypical of either RBBB or LBBB. In 51 patients ventricular extraplane loop was often atypical of either RBBB or LBBB. In 51 patients ventricular extrasystoles and an initial delay which was prolonged into the efferent limb of the QRS loop with acceleration of the afferent limb and/or the QRS loop was directed anteriorly, inferiorly and to the left. Conventional recordings of these extrasystoles usually showed an initial slow upstroke (or downstroke) of the QRS resembling a delta wave. It is suggested that extrasystoles resembling bundle-branch complexes arise close to the main bundle branches but that the other extrasystoles arise at the Purkinje-myocardial junction. Identification and differentiation of ventricular extrasystoles from aberrant conduction is aided by vectorcardiography.  相似文献   
993.
994.

Purpose  

The purpose of the study was to assess the diagnostic performance of positron emission tomography/computed tomography and fluorodeoxyglucose (18F) (FDG PET/CT) for the staging and the follow-up of anal carcinoma, and to evaluate the impact of FDG PET/CT on patient management.  相似文献   
995.
J D Talbot  G H Duncan  M C Bushnell  M Boyer 《Pain》1987,30(2):221-232
Counterirritation, the phenomenon of one painful stimulus reducing pain caused by a second noxious stimulus, has been recognized clinically for decades. Recently a physiological mechanism to explain counterirritation was described and termed diffuse noxious inhibitory controls (DNICs). Nevertheless, few psychophysical studies have examined systematically the effects of a noxious conditioning stimulus on pain perception. The present study examined the perception of painful heat stimuli on the face before, during and after the subject submerged a hand in painfully cold water (5 degrees C) for 5 min (cold pressor pain). We found that the subjects' ratings of the heat stimuli were significantly, although not completely, reduced during the cold pressor pain; this attenuation of pain perception continued after the noxious conditioning stimulus was withdrawn. Similarly, the pain threshold was significantly increased from 45.7 degrees C to 47.3 degrees C while the hand was in cold water and this threshold remained elevated after the cold water was terminated. Since DNICs have been found to completely and selectively inhibit the activity of only one type of pain transmission neuron (wide dynamic range), our data suggest that these neurons are involved in the perception of pain intensity. However, the persistence of residual pain perception in the presence of noxious conditioning stimuli indicates the importance of other nociceptive pathways.  相似文献   
996.
The relation of lipid metabolism to nitrogen balance was studied in patients having undergone abdominal surgery and was compared with control subjects who had fasted for a similar period. The patients had lower circulating concentrations of glycerol, non-esterified fatty acids and ketone bodies. There were inverse correlations between blood alanine and ketone body concentrations in both patients (r = -0.64, P less than 0.01) and controls (r = -0.58, P less than 0.01). Nitrogen excretion by patients (12.7 mmol/kg body weight/day +/- 1.4 s.e. mean) was greater than by controls (9.2 mmol kg(-1)d(-1) +/- 0.8, P less than 0.05), but a more marked difference was noted for urinary methyl histidine excretion of 5.1 +/- 0.5 mmumol kg(-1) d(-1) by patients and only 2.5 +/- 0.3 mumol kg(-1) d(-1) by controls (P less than 0.01), a disparity indicative of more active protein turnover after surgery.  相似文献   
997.
The effect of elastic compression on venous flow in the legs provided by carefully fitted stockings has been measured by a venographic technic. The stocking used provides a gradually decreasing compression from ankle to groin. Clearance of stagnant blood from behind venous valves is clearly improved and the differences observed are statistically highly significant. These data suggest that the routine use of carefully fitted compression stockings will result in a decreased incidence of deep vein thrombosis (DVT) and provide a singularly safe, convenient, and noninvasive method of prophylaxis. Evidence presented suggests that at least two investigators have failed to show a decreased incidence of DVT in limbs subjected to elastic compression because the method of compression was inadequate.  相似文献   
998.
INTRODUCTION: Biliary complications remain a major cause of morbidity and mortality in patients following liver transplantation. We sought to identify possible risk factors predisposing to biliary complications after OLT using duct-to-duct biliary reconstruction. MATERIALS AND METHODS: We retrospectively reviewed 5 years of prospectively collected donor and recipient data between April 1999 and April 2004. We evaluated the presence of biliary complications, donor and recipient age, cold ischemia time, hepatic artery thrombosis, non-heart-beating donor (NHBD), and graft steatosis (>30%). The results were compared with a control group of OLT patients without biliary complications. RESULTS: Among 173 OLT recipients, biliary complications occurred in 28 patients (16.2%), of whom 12 were leaks, 15 strictures, and 1 a nonanastomotic intrahepatic stricture. The mortality following biliary complications was 11%, compared to 6% in the control group. CONCLUSION: Biliary complications remain a persistent problem in OLT. Analysis of risk factors identified hepatic artery thrombosis and steatosis as predisposing factors. With greater experience, NHBD livers may also prove to be at greater risk of biliary complications.  相似文献   
999.
Neonatal brain injury renders the developing brain vulnerable to oxidative stress, leading to cognitive deficit. However, oxidative stress-induced damage to hippocampal circuits and the mechanisms underlying long-term changes in memory and learning are poorly understood. We used high oxygen tension or hyperoxia (HO) in neonatal mice of both sexes to investigate the role of oxidative stress in hippocampal damage. Perinatal HO induces reactive oxygen species and cell death, together with reduced interneuron maturation, inhibitory postsynaptic currents, and dentate progenitor proliferation. Postinjury interneuron stimulation surprisingly improved inhibitory activity and memory tasks, indicating reversibility. With decreased hippocampal levels of Wnt signaling components and somatostatin, HO aberrantly activated glycogen synthase kinase 3 β activity. Pharmacological inhibition or ablation of interneuron glycogen synthase kinase 3 β during HO challenge restored progenitor cell proliferation, interneuron development, inhibitory/excitatory balance, as well as hippocampal-dependent behavior. Biochemical targeting of interneuron function may benefit learning deficits caused by oxidative damage.SIGNIFICANCE STATEMENT Premature infants are especially vulnerable to oxidative stress, as their antioxidant defenses are underdeveloped. Indeed, high oxygen tension is associated with poor neurologic outcomes. Because of its sustained postnatal development and role in learning and memory, the hippocampus is especially vulnerable to oxidative damage in premature infants. However, the role of oxidative stress in the developing hippocampus has yet to be explored. With ever-rising rates of neonatal brain injury and no universally viable approach to maximize functional recovery, a better understanding of the mechanisms underlying neonatal brain injury is needed. Addressing this need, this study uses perinatal hyperoxia to study cognitive deficits, pathophysiology, and molecular mechanisms of oxidative damage in the developing hippocampus.  相似文献   
1000.
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