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1.
PurposeThis study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS).Materials and MethodsData from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3–164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT.ResultsSeven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2–61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0–53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159–115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406–163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369–954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495–267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915–2309.848) were predictors of ipsilateral DVT.ConclusionsContralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis.  相似文献   
2.
肛直肠抑制反射时门静脉血中P物质变化   总被引:1,自引:0,他引:1  
目的探讨肛直肠抑制反射(RAIR)时门静脉血中P物质(SP)的变化规律及外源性内脏神经对其变化的影响。方法将实验大白鼠分为7组,其中6组先按去与不去直肠肛管外源性内脏神经支配而分为不去神经和去神经两大组,每组中又按Foley导管上气囊置入直肠腔中的位置分为2、4、6cm组;同时再设1个对照组,将Foley导管置入直肠腔中,但不注水扩张球囊。检测并比较在直肠腔内刺激后,各组门静脉血中的SP值及变化情况。结果去神经组中2、4cm组与不去神经组之间及对照组之间,门静脉血中SP值变化比较,P〉0.05,差异无统计学意义。不去神经组中的6cm组与对照组及去神经组中2cm和4cm组之间SP值比较,P〈0.01,差异有统计学意义;去神经组和不去神经组中的6cm组之间SP值比较,P〈0.01,差异有统计学意义。结论直肠腔内上部的刺激不引出RAIR可能与该部位的刺激使内括约肌兴奋性递质(SP)的释放有关;外源性内脏神经对RAIR中门静脉血的SP变化有调控作用。  相似文献   
3.
Summary. A new apparatus which measures the blood pressure in the finger continuously and yet not invasively was tested for its usefulness during exercise. It was compared with upper arm measurements in 23 volunteers during prolonged bicycle ergometry. Simultaneously, a pulse plethysmogram was recorded from another finger of the same arm, whereas in six additional volunteers Doppler measurements were carried out on the radial artery. The results show that finger systolic pressure ceased to rise at about 40% of maximal exercise; the difference with the continuously rising systolic pressure in the upper arm becoming significant at 140 W. At the same time the amplitude of the finger plethysmogram became significantly higher than its initial value, indicating distinct cutaneous vasodilation, whereas the volunteers also became hot and started to perspire. However, the radial artery ‘flow’, deduced from the Doppler measurements, did not change significantly during exercise. It increased sharply and markedly in the cooling down period. Simultaneously with this increase in flow, HR and both systolic blood pressures fell drastically whereas the plethysmography amplitude remained about stable at its raised level. The results fit in with the idea that a compromise is achieved between the need for muscle activity and the need for temperature regulation. It is concluded that the Finapres functions well during exercise, but that the systolic pressure in the finger is not representative for its more central counterpart during cutaneous vasodilation. It is argued that opening up of AVAs may contribute to this pressure effect.  相似文献   
4.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure.  相似文献   
5.
Abstract   We evaluated the associations between glycemic therapies and prevalence of diabetic peripheral neuropathy (DPN) at baseline among participants in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial on medical and revascularization therapies for coronary artery disease (CAD) and on insulin-sensitizing vs. insulin-providing treatments for diabetes. A total of 2,368 patients with type 2 diabetes and CAD was evaluated. DPN was defined as clinical examination score >2 using the Michigan Neuropathy Screening Instrument (MNSI). DPN odds ratios across different groups of glycemic therapy were evaluated by multiple logistic regression adjusted for multiple covariates including age, sex, hemoglobin A1c (HbA1c), and diabetes duration. Fifty-one percent of BARI 2D subjects with valid baseline characteristics and MNSI scores had DPN. After adjusting for all variables, use of insulin was significantly associated with DPN (OR = 1.57, 95% CI: 1.15–2.13). Patients on sulfonylurea (SU) or combination of SU/metformin (Met)/thiazolidinediones (TZD) had marginally higher rates of DPN than the Met/TZD group. This cross-sectional study in a cohort of patients with type 2 diabetes and CAD showed association of insulin use with higher DPN prevalence, independent of disease duration, glycemic control, and other characteristics. The causality between a glycemic control strategy and DPN cannot be evaluated in this cross-sectional study, but continued assessment of DPN and randomized therapies in BARI 2D trial may provide further explanations on the development of DPN.  相似文献   
6.
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects.  相似文献   
7.
Physiologic assessment of diseases of the motor unit from the anterior horn cells to the muscles relies on a combination of needle electromyography (EMG) and nerve conduction studies (NCS). Both require a unique combination of knowledge of peripheral nervous system anatomy, physiology, pathophysiology, diseases, techniques, and electricity is necessary. Successful, high‐quality, reproducible EMG depends on the skills of a clinician in patient interaction during the physical insertion and movement of the needle while recording the electrical signals. These must be combined with the skill of analyzing electric signals recorded from muscle by auditory pattern recognition and semiquantitation. 10 , 52 This monograph reviews the techniques of needle EMG and waveform analysis and describes the types of EMG waveforms recorded during needle EMG. © 2009 Wiley Periodicals, Inc. Muscle Nerve 39: 244–270, 2009  相似文献   
8.
The disintegrin and metalloproteinase 10 (ADAM10) is a membrane‐anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co‐cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG‐SC co‐cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate‐based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve. © 2009 Wiley‐Liss, Inc.  相似文献   
9.
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.  相似文献   
10.
Central Sensitization Theory of Migraine: Clinical Implications   总被引:4,自引:2,他引:2  
David Dodick  MD  ; Stephen Silberstein  MD 《Headache》2006,46(S4):S182-S191
The clinical science of migraine headache continues to evolve. Theories of the pathophysiology of migraine have progressed from the early vascular basis of migraine to more complex current theories that emphasize the centrality of neuronal dysfunction. The most recently articulated theory of migraine is the central sensitization hypothesis, which proposes that altered processing of sensory input in the brainstem, principally the trigeminal nucleus caudalis, could account for many of the temporal and symptomatic features of migraine, as well as its poor response to triptan therapy when such treatment is initiated hours after the onset of pain. Both preclinical and clinical data support the central sensitization theory. A critical clinical implication of this theory is that drugs that are capable of either aborting or arresting the process of central sensitization, most prominently dihydroergotamine, may have a unique role in the treatment of migraine. An additional, and highly practical, implication is based upon the finding that cutaneous allodynia—pain arising from innocuous stimulation of the skin, as in hair brushing or the application of cosmetics—is an easily identifiable marker of central sensitization. Thus, the presence or absence of cutaneous allodynia can be integrated into the routine clinical assessment of migraine and utilized as a determinant of treatment. Future basic and clinical research on central sensitization is likely to be of ongoing importance to the field.  相似文献   
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