全文获取类型
收费全文 | 19304篇 |
免费 | 1030篇 |
国内免费 | 109篇 |
专业分类
耳鼻咽喉 | 165篇 |
儿科学 | 267篇 |
妇产科学 | 286篇 |
基础医学 | 2364篇 |
口腔科学 | 472篇 |
临床医学 | 1194篇 |
内科学 | 4823篇 |
皮肤病学 | 396篇 |
神经病学 | 1442篇 |
特种医学 | 884篇 |
外科学 | 3643篇 |
综合类 | 76篇 |
一般理论 | 1篇 |
预防医学 | 439篇 |
眼科学 | 211篇 |
药学 | 1291篇 |
中国医学 | 43篇 |
肿瘤学 | 2446篇 |
出版年
2023年 | 131篇 |
2022年 | 239篇 |
2021年 | 460篇 |
2020年 | 235篇 |
2019年 | 345篇 |
2018年 | 405篇 |
2017年 | 351篇 |
2016年 | 450篇 |
2015年 | 435篇 |
2014年 | 548篇 |
2013年 | 653篇 |
2012年 | 986篇 |
2011年 | 1146篇 |
2010年 | 639篇 |
2009年 | 586篇 |
2008年 | 977篇 |
2007年 | 1055篇 |
2006年 | 1002篇 |
2005年 | 991篇 |
2004年 | 1031篇 |
2003年 | 962篇 |
2002年 | 963篇 |
2001年 | 539篇 |
2000年 | 512篇 |
1999年 | 522篇 |
1998年 | 245篇 |
1997年 | 221篇 |
1996年 | 177篇 |
1995年 | 182篇 |
1994年 | 114篇 |
1993年 | 108篇 |
1992年 | 290篇 |
1991年 | 233篇 |
1990年 | 263篇 |
1989年 | 289篇 |
1988年 | 281篇 |
1987年 | 265篇 |
1986年 | 225篇 |
1985年 | 227篇 |
1984年 | 129篇 |
1983年 | 127篇 |
1982年 | 59篇 |
1979年 | 114篇 |
1978年 | 76篇 |
1977年 | 49篇 |
1974年 | 48篇 |
1972年 | 53篇 |
1971年 | 54篇 |
1970年 | 48篇 |
1969年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Yoshio Mitsuyama M.D Hiroyuki Hashiguchi M.D Toshihiko Murayama M.D Masashi Koono M.D Shohei Nishi M.D 《Psychiatry and clinical neurosciences》1992,46(3):741-748
Abstract: A 78-year-old male with renal carcinoma was treated with a high dose infusion of interferon-alpha (IFN-alpha) for eight months. The patient had evidence of organlc brain syndrome such 88 : dysfunction of memory, slowing of behavior, and development of mental confusion that appeared eight months after the treatment. MRI at the time of mental confusion revealed difise white matter lesions. Neuropathologic findings were compatible to Binswanger's disease and Senile Dementia of Alzheimer Type (SDAT), Preexisting neurologic abnormalities including intracerebral arteriosclerosis and cerebral atrophy may increase susceptibility to unacceptably severe IFN neurotoxicity. 相似文献
62.
We recorded somatosensory evoked potentials (SEPs) from the skin surface and spinal evoked potentials (SpEP) from the posterior epidural space after median nerve stimulation in 11 patients with cervical syringomyelia. We compared SEPs with SpEP to assess the possible feasibility of using these techniques to localize the offending lesion. SEP abnormalities were present on one or both sides of 7 patients (9 of 22 upper limbs; 41%). The abnormal SEP pattern was the attenuation or loss of N13, which was of little value for delineating the lesion. In patients with abnormal SEPs, three types of abnormal SpEPs were noted. In the Type A abnormality (three limbs), potentials were attenuated in all cervical segments, suggesting that the syrinx itself had enlarged to involve the posterior column. In Type B (two limbs), there was reduced amplitude or absent upper cervical potentials, probably a result of the accompanying tonsilar herniation. Finally, the Type C (four limbs) abnormality was a mixture of Type A and B abnormalities in that the attenuated cervical potentials were again affected in the most upper cervical segment. We concluded that SpEP revealed various kinds of involvement of the dorsal column pathway in the syringomyelic patients, a finding not expressed with conventional SEPs. 相似文献
63.
Masashi Kimura M.D. Kenji Shirakura M.D. Atsushi Hasegawa M.D. Yasukazu Kobayashi M.D. Eiichi Udagawa M.D. 《Arthroscopy》1992,8(4):419-423
An arthroscopic and anatomical investigation was performed to define the abnormal conditions of the popliteal tendon area in a lateral meniscus. Arthroscopic findings for 100 patients and anatomical observations of 10 amputated knees were analyzed. Five of the 10 dissected menisci were also examined histologically. Menisco-tibial coronary ligaments were classified into two types, as follows: type I--a coronary ligament covering an entire popliteal tendon beneath the meniscus; type II--a popliteal tendon visible beneath the meniscus through defects of the coronary ligament. Twenty-one of 100 cases were classified as type I, and 79 were classified as type II. Three of the 10 anatomical dissections were type I, and the remaining 7 were type II. Menisci in which the type I coronary ligaments were thought to be torn and menisci with type II coronary ligaments showed a rather marked mobility, but no conclusion could be reached. 相似文献
64.
Yu Kojima Hisao Fujii Renta Katsui Yoshiyuki Nakajima Miyako Takaki 《Journal of Smooth Muscle Research》2006,42(5):139-147
The defecation reflex is composed of rectal distension-evoked rectal (R-R) reflex contractions and synchronous internal anal sphincter (R-IAS) reflex relaxations in guinea pigs. These R-R and R-IAS reflexes are controlled via extrinsic sacral excitatory nerve pathway (pelvic nerves), lumbar inhibitory nerve pathways (colonic nerves) and by intrinsic cholinergic excitatory and nitrergic inhibitory nerve pathways. The effect of mosapride (a prokinetic benzamide) on the intrinsic reflexes, mediated via enteric 5-HT(4) receptors, was evaluated by measuring the mechanical activity of the rectum and IAS in anesthetized guinea pigs using an intrinsic R-R and R-IAS reflex model resulting from chronic (two to nine days) lumbosacral denervation (PITH). In this model, the myenteric plexus remains undamaged and the distribution of myenteric and intramuscular interstitial cells of Cajal is unchanged. Although R-R and R-IAS reflex patterns markedly changed, the reflex indices (reflex pressure or force curve-time integral) of both the R-R contractions and the synchronous R-IAS relaxations were unchanged. The frequency of the spontaneous R and IAS motility was also unchanged. Mosapride (0.1-1.0 mg/kg) dose-dependently increased both intrinsic R-R (maximum: 1.82) and R-IAS reflex indices (maximum: 2.76) from that of the control (1.0) 6-9 days following chronic PITH. The dose-response curve was similar to that in the intact guinea pig, and had shifted to the left from that in the guinea pig after acute PITH. A specific 5-HT(4) receptor antagonist, GR 113808 (1.0 mg/kg), decreased both reflex indices by approximately 50% and antagonized the effect of mosapride 1.0 mg/kg. This was quite different from the result in the intact guinea pig where GR 113808 (1.0 mg/kg) did not affect either of the reflex indices. The present results indicate that mosapride enhanced the intrinsic R-R and R-IAS reflexes and functionally compensated for the deprivation of extrinsic innervation. The actions of mosapride were mediated through endogenously active, intrinsic 5-HT(4) receptors which may be post-synaptically located in the myenteric plexus of the anorectum. 相似文献
65.
The purpose of this study was to determine whether the late component of somatosensory evoked potentials (SEP) induced by electrical tooth stimulation and pain intensity are inhibited by heterotopic ischemic stimulation. The tourniquet pressure with 50 mmHg greater than the individual's systolic pressure was applied to the left upper arm for 10 min as ischemic conditioning stimulation. The late component of SEP and visual analogue scale (VAS) were recorded at 4 times and both were significantly decreased when ischemic conditioning stimulation was applied. The maximum reductions in SEP amplitude and the VAS value were 26.1% and 21.2%, respectively, during ischemic conditioning stimulation. After-effect was observed 5 min after removal of the conditioning stimulation. The present study revealed that heterotopic ischemic stimulation attenuated the late component of SEP induced by electrical tooth stimulation, triggering diffuse noxious inhibitory controls (DNIC) and after-effects in the trigeminal nerve territory. It was also suggested that the DNIC effect differs, depending on the intensity, kind, and quality of the test and conditioning stimuli. 相似文献
66.
Masashi Watanabe Haruhiro Nakazaki Natsuki Tokura Wataru Takita Kazuo Kobayashi 《Journal of hepato-biliary-pancreatic sciences》2004,11(6):422-425
Hemosuccus pancreaticus (HP) is a rare cause of gastrointestinal bleeding, usually due to rupture of a visceral artery aneurysm in chronic pancreatitis. Other causes of HP are rare. We present a case of HP which occurred in a patient with chronic calcifying pancreatitis and a pancreatic pseudocyst documented by ultrasonography and computed tomography. With detectable fresh blood in the descending duodenum, an aneurysm in the pancreatic head was revealed by superior mesenteric angiography as the suspected origin of intermittent bleeding from the pancreatic duct. Because an artery feeding the pseudocyst could not be identified, angiographic embolization was not possible. Surgical resection or ligation was difficult by laparotomy; therefore, intraoperative packing of the pseudocyst with absorbable gelatin sponges was achieved via a cannula through a directly punctured site in the pseudocyst wall. The patient has been followed for 4.25 years with no further episodes of HP. It is possible that the packing of a pancreatic pseudocyst with gelatin sponges is a method that can be used in similar cases, where control of hemostasis is the primary concern. The packing of a pancreatic pseudocyst with gelatin sponges is a technique that can be performed not only via laparotomy but also via laparoscopy or concomitant angiography and ultrasonography. 相似文献
67.
Clinical Course and Autopsy Findings of a Patient with Clival Chordoma Who Underwent Multiple Surgeries and Radiation during a 10-Year Period.
下载免费PDF全文
![点击此处可从《Skull base》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Masashi Tamaki Masaru Aoyagi Toshihiko Kuroiwa Masaaki Yamamoto Seiji Kishimoto Kikuo Ohno 《Skull base》2007,17(5):331-340
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques. 相似文献
68.
Masashi Hamada Ritsuko Hanajima Yasuo Terao Noritoshi Arai Toshiaki Furubayashi Satomi Inomata-Terada Akihiro Yugeta Hideyuki Matsumoto Yuichiro Shirota Yoshikazu Ugawa 《Clinical neurophysiology》2007,118(12):2672-2682
OBJECTIVE: Repetitive paired-pulse transcranial magnetic stimulation (TMS) at I-wave periodicity has been shown to induce a motor-evoked potential (MEP) facilitation. We hypothesized that a greater enhancement of motor cortical excitability is provoked by increasing the number of pulses per train beyond those by paired-pulse stimulation (PPS). METHODS: We explored motor cortical excitability changes induced by repetitive application of trains of four monophasic magnetic pulses (quadro-pulse stimulation: QPS) at 1.5-ms intervals, repeated every 5s over the motor cortex projecting to the hand muscles. The aftereffects of QPS were evaluated with MEPs to a single-pulse TMS, motor threshold (MT), and responses to brain-stem stimulation. These effects were compared to those after PPS. To evaluate the QPS safety, we also studied the spread of excitation and after discharge using surface electromyograms (EMGs) of hand and arm muscles. RESULTS: Sizes of MEPs from the hand muscle were enhanced for longer than 75min after QPS; they reverted to the baseline at 90min. Responses to brain-stem stimulation from the hand muscle and cortical MEPs from the forearm muscle were unchanged after QPS over the hand motor area. MT was unaffected by QPS. No spreads of excitation were detected after QPS. The appearance rate of after discharges during QPS was not different from that during sham stimulation. CONCLUSIONS: Results show that QPS can safely induce long-lasting, topographically specific enhancement of motor cortical excitability. SIGNIFICANCE: QPS is more effective than PPS for inducing motor cortical plasticity. 相似文献
69.
Kuniaki Nakahara Satoru Shimizu Satoshi Utsuki Sachio Suzuki Hidehiro Oka Kiyotaka Fujii 《Child's nervous system》2007,23(8):863-865
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent
hydrocephalus development.
Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with
(group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal
shunt (VPS) placement.
Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five
had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth
required VPS placement (p=0.0001).
Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine
the necessity for VPS placement. 相似文献
70.
Toshiro SAKAMOTO Youya EBISU Aya IKEDA Masashi NAKAYA Tomoyuki NISHIZAKI 《Psychogeriatrics》2007,7(2):76-80
Background: The hippocampus is a center of cognitive function and therefore hippocampal atrophy is the major factor in cognitive decline. Analysis of hippocampal size may make it possible to predict progression in cognitive impairment. To address this point, the present study investigated the relationship between hippocampal atrophy and dementia using magnetic resonance (MR) images and the Hasegawa Dementia Scale‐Revised (HDS‐R). Methods: The present study was performed on 274 subjects (14–97 years old; average, 66 years; 106 male and 168 female) who had no focal neurological deficit. Hippocampal area and whole brain area were measured in three series of coronal MR images taken from a 5‐mm slice rostrally along dorsal edge of the pons, and hippocampal size normalized by calculating summated hippocampal areas as percentages of summated whole brain areas. Dementia was screened for using HDS‐R. Results: Hippocampal size decreased and HDS‐R reduced with age. Hippocampal atrophy was highly correlated with cognitive deterioration; a critical normalized hippocampal size for HDS‐R of less than 20, which corresponds with mild cognitive impairment and dementia, was found in 65% of over 60‐years old subjects and 98% of subjects with HDS‐R of less than 20 were over 60 years old. Conclusion: There is a high probability that over 60‐year‐old people with a normalized hippocampal size of less than 1.0 would develop dementia in the future, even though their HDS‐R might presently be over 20. Measurement of hippocampal size with coronal MR imaging may therefore contribute to prospective diagnoses of age‐related dementia. 相似文献