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991.
Experimental vascularized total joint autografts--a primate study   总被引:1,自引:0,他引:1  
Autogenous vascularized and nonvascularized total joint transfers were studied in the hands of Macaca fascicularis monkeys. Nine second toe proximal interphalangeal joints were transferred as a vascularized free graft to the hand, and the excised finger joints were transferred to the foot as a nonvascularized free graft. The grafts were examined clinically and histopathologically at 16 weeks to 10 months. Two of the nonvascularized free grafts were amputated because of infection and necrosis. Three had chronic infections. The four surviving nonvascularized grafts demonstrated necrosis of the hyaline cartilage and degenerative changes. Of the nine vascularized joints, one developed a wound infection that required amputation, another failed at 2 weeks because of wound dehiscence, and the remaining seven survived with preservation of the hyaline articular surfaces. The experimental technique was designed to be easily applied to clinical use. A skin island is provided as a "patency/viability monitor." The extensor mechanism is included in the graft for early function.  相似文献   
992.
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory.  相似文献   
993.
Two newborn infants with duodenal and jejunal atresia and agenesis of the dorsal mesentery represent our surgical experience with "apple peel" small bowel or "christmas tree" demormity. The first patient had the typical appearance of this condition. The postoperative course was complicated by hyperbilirubinemia, septicemia, and disseminated intravascular coagulation. The infant is in satisfactory condition 1.5 years after operation. The second patient had agenesis of the dorsal mesentery without spiraling of the bowel around its vascular stalk. The child died after 1 month, with complete absence of extrahepatic bile ducts as seen at a second laparotomy. Neither child had been subjected to gastrostomy.  相似文献   
994.
Venous congestion in a replanted or transplanted digit can be detected, even before any obvious color changes, by the "throbbing" elicited by pinching the digit between the thumb and finger of the examiner until the skin blanches. Releasing the pressure slowly, a sensation of throbbing will be felt synchronous with the patient's pulse rate. The sign disappears when venous congestion is relieved or when swelling persists and increases enough to lessen the arterial inflow.  相似文献   
995.
Zusammenfassung Es wird die funktionelle Morphologie des bisher wenig bekannten M. canalis ani beschrieben. Dieser Muskel liegt dem Sphincter ani internus auf und zieht längs durch die submuköse und subcutane Schicht des Analkanals. Es wird gezeigt, daß er ein Bestandteil des Kontinenzorgans ist und für den Verlauf anorectaler Erkrankungen bedeutsam ist.
The importance of the musculus canalis ani for continence and anorectal diseases
Summary The functional morphology of the M. canalis ani is described. Hitherto this muscle has not been studied in detail. The M. canalis ani is located inside of the M. sphincter ani internus and reaches through the spatium submucosum et subcutaneum of the analcanal. This muscle is part of a described organ of continence. Its importance in the course of anorectal disease is shown.
  相似文献   
996.
This study assessed behavioural and neurochemical effects of i.c.v. injections of both the cholinergic toxin 192 IgG-saporin (2 microgram) and the serotonergic toxin 5,7-dihydroxytryptamine (5,7-DHT; 150 microgram) in Long-Evans female rats. Dependent behavioural variables were locomotor activity, forced T-maze alternation, beam walking, Morris water-maze (working and reference memory) and radial-maze performances. After killing by microwave irradiation, the concentrations of acetylcholine, monoamines and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the hippocampus, frontoparietal cortex and striatum. 192 IgG-saporin reduced the concentration of acetylcholine by approximately 40% in the frontoparietal cortex and hippocampus, but had no effect in the striatum. 5,7-DHT lesions reduced the concentration of serotonin by 60% in the frontoparietal cortex and 80% in the hippocampus and striatum. Noradrenaline was unchanged in all structures except the ventral hippocampus where it was slightly increased in rats given 192 IgG-saporin. Cholinergic lesions induced severe motor deficits but had no other effect. Serotonergic lesions produced diurnal and nocturnal hyperactivity but had no other effect. Rats with combined lesions were more active than those with only serotonergic lesions, showed motor dysfunctions similar to those found in rats with cholinergic lesions alone, and exhibited impaired performances in the T-maze alternation test, the water-maze working memory test and the radial-maze. Taken together and although cholinergic lesions were not maximal, these data show that 192 IgG-saporin and 5,7-DHT lesions can be combined to selectively damage cholinergic and serotonergic neurons, and confirm that cholinergic-serotonergic interactions play an important role in some aspects of memory, particularly in spatial working memory.  相似文献   
997.
gamma-amino butyric acid (GABA) is the major inhibitory neurotransmitter in the CNS, mediating fast inhibitory synaptic transmission, by activating GABAA receptors. However, these GABA-gated Cl- channels can also be excitatory, causing depolarization, and increasing Ca2+ entry via voltage-operated Ca2+ channels (VOCCs). Evidence exists for excitatory ionotropic GABA receptors in anterior pituitary cells, including gonadotropes, but these have not been directly characterized and their pharmacology remains controversial. Here we have measured the cytosolic Ca2+ concentration ([Ca2+]i) in alphaT3-1 gonadotropes, to test for expression of excitatory GABA receptors. The GABAA agonists, GABA and muscimol, both caused rapid, robust and dose-dependent increases in [Ca2+]i (EC50 values 2.7 and 1 microM), whereas the GABAB agonist, baclofen, did not. The GABAA antagonist, bicuculline, inhibited muscimol's effect, whereas the GABAB antagonist, phaclofen, did not. The neuroactive steroid 5alpha-pregnan-3alpha-ol-11,20-dione (an allosteric activator of GABAA receptors) increased [Ca2+]i, and this effect, like that of muscimol, was inhibited by picrotoxin. The muscimol effect on [Ca2+]i was blocked by the VOCC antagonist, nifedipine, or by Ca2+-free medium. When cells were pretreated with muscimol this increased the spike phase of the [Ca2+]i response to subsequent stimulation with gonadotropin-releasing hormone (GnRH). Similar amplification was seen in muscimol-pretreated cells stimulated with GnRH in Ca2+-free medium, but not when cells were pretreated with muscimol in Ca2+-free medium. The amplification was not, however, GnRH receptor-specific, because the spike response to ionomycin was also increased by muscimol pretreatment. These data provide the first direct evidence for expression of excitatory GABAA receptors, and the first demonstration of acute steroid effects, on GnRH-responsive pituitary cells. They also reveal a novel mechanism by which GABAA activation modulates GnRH action, raising the possibility that this may also influence gonadotrophin secretion from non-immortalized gonadotropes.  相似文献   
998.
Our purpose was to investigate nonhaemorrhagic infarcts with a short T1 in the cerebellum and basal ganglia. We carried out repeat MRI on 12 patients with infarcts in the cerebellum or basal ganglia with a short T1. Cerebellar cortical lesions showed high signal on T1-weighted spin-echo images beginning at 2 weeks, which became prominent from 3 weeks to 2 months, and persisted for as long as 14 months after the ictus. The basal ganglia lesions demonstrated slightly high signal from a week after the ictus, which became more intense thereafter. Signal intensity began to fade gradually after 2 months. High signal could be seen at the periphery until 5 months, and then disappeared, while low or isointense signal, seen in the central portion from day 20, persisted thereafter. Received: 1 February 1999 Accepted: 13 September 1999  相似文献   
999.
如何从体质中寻找中医病因--兼述一个中西医结合方法   总被引:1,自引:1,他引:1  
体质,是对个体生命结构及生命活动基本特点的概括。体质异常是遗传和遗传倾向性疾病发生的根本原因,因此确定了体质类型也就找到了这种疾病的病因。具体讲,我们目前所用的方法是:1、以现代医学病名定中医病名。先确定一定样本病人发病前体质的共有特点,即某种疾病的易患体质,找出体质中的不正常成分(按中医理论);2、分析发病后的证候演变规律,审证求因;3、将发病前体质的不正常成分与病后证候演变综合分析,找出其中的因果关系,并与审计所求之因对照,初步确定病因;4、通过四诊微观化/四诊延伸方法,将西医的病理指标、细菌/分子生物学诊断指标和研究成果等纳入中医诊断体系,再与发病后中医诊断及审证求因结果综合分析,将病因诊断细致化,并确定病机;5、在此病机基础上确定治则治法,并在实验室和临床进行反证。以急性白血病病因病机的确定过程为例进行了演示,同时论述了体质学检验方法对疾病和亚健康状态病因诊断的普遍适用价值。  相似文献   
1000.
通痹灵总碱对T淋巴细胞活化CD71表达的影响   总被引:2,自引:0,他引:2  
目的 :通痹灵总碱 (TBL)是从通痹灵中提取出来的总生物碱部位。本研究旨在探索TBL对T淋巴细胞活化CD71表达的影响 ,探讨通痹灵免疫调控作用的机理。方法 :对清洁级小鼠T淋巴细胞进行培养 ,体外加入通痹灵总碱 ,采用流式细胞仪检测T淋巴细胞CD71的表达率。结果 :TBL(10 0 μg mL)对ConA或PDB激活的大鼠T淋巴细胞活化表达CD3+ CD71+ 抗原有明显的下调作用 (P <0 0 1) ,并且随着剂量的增加 ,其抑制作用加强 (P <0 0 1) ,呈明显的量效关系 ;对ConA活化组的作用要强于PDB。结论 :TBL对ConA和PDB诱导活化T细胞的CD71表达率均有明显的抑制作用 ,而且呈明显的量效关系。提示对TBL在T细胞活化信号传导过程有明显作用 ,在治疗RA的过程中可能可以通过影响上游T淋巴细胞的活化 ,调节其细胞免疫机制来达到治疗RA的目的。  相似文献   
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