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81.
中央沟上段及其邻近沟回的体表定位及其临床意义   总被引:2,自引:0,他引:2  
目的:探讨在MRI和CT图像上观测中央沟上段及其邻近沟回的特征,进行精确体表定位。方法:30例成人头颅和扫描无颅恼器质性病变10份CT,100份MRI片,在头颅正中欠状面上观测头颅外形和平行于耳眦线平而以上100mm内的前后正巾线的中点及中垂线。在横位图像上观测中央沟上段及其邻近沟回的特征和二维坐标参数。结果:成人头颅近似标准球形。住82%头颅卜平行耳眦线平面的正中点的的投影在垂直耳眦线过外耳道的直线卜,另外18%偏离基线面中垂线小于7mm。上段中央沟在耳眦线平面上70~95mm。84%额上沟与中央前沟相交呈倒T字征,交点住前后中线旁24~27mm,耳眦线平面的中垂线前2~6mm。中央沟上段起点前后中线旁1~15mm,耳眦线平而的中垂线后12~28mm,手结征98%。中央后沟在中央沟之后8~13mm与其平行。结论:每人上段中央沟及其邻近沟回的特征能被MRI精确体表定位。  相似文献   
82.
AIMS: To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes ('at risk' group, AR) and control females (control group, C). METHODS: At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R') and insulin secretion (HOMA beta') were obtained from fasting insulin and glucose concentrations. RESULTS: At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R' and HOMA beta'. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 +/- 0.2 vs. 4.3 +/- 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA beta' (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA beta'. CONCLUSIONS: Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG.  相似文献   
83.
经单侧半椎板切除髓内海绵状血管瘤   总被引:1,自引:0,他引:1  
目的探讨脊髓髓内海绵状血管瘤的出血性损伤风险、临床特征以及经单侧半椎板切除髓内海绵状血管瘤的手术技巧。方法回顾性分析11例髓内海绵状血管瘤病人的病历资料。均经单侧半椎板切除肿瘤。采用统计学分析,在性别分布、平均年龄、年出血率等方面与同期颅内(145例)、脑干(61例)海绵状血管瘤进行比较。术前Frankel分级D级8例,C级2例,A级1例。结果本组女性7例,男性4例.女性与男性之比高于颅内(80:65)和脑干(33:28)海绵状血管瘤;年出血率为2.8%/病人,稍低于颅内(3.3%)和脑干(3.1%)海绵状血管瘤。病变均获全切:术后随访期内8例神经系统症状改善(Frankel分级D级升到E级6例,C级升到D级2例).3例临床症状无变化。结论脊髓髓内海绵状血管瘤应全切以防复发和再出血;选择微侵袭的半椎板入路,以及术中采用体感诱发电位监护.是取得满意结果、预防附加损伤的关键.  相似文献   
84.
Bronchoalveolar lavage (BAL) performed with a fiberoptic bronchoscope (FOB) is a useful method for sampling alveolar contents. Since the smallest FOB with a channel has a diameter of 3.6 mm, BAL is difficult to accomplish through artificial airways (AA) less than 5.0 mm I.D. We used a 4F balloon wedge pressure catheter to perform BAL through small AA. Supplemental O2 or ventilatory support was delivered via an adaptor through which the catheter was introduced. After it was passed distal to the AA, the balloon was inflated with normal saline (NS) to a predetermined volume, and advanced until resistance was felt. The balloon was deflated, advanced slightly, and then reinflated to achieve airway occlusion. Five aliquots of 0.75 mL/kg of NS were used for BAL. The procedure was performed in 20 children from 1 month (950 g) to 6 1/2 years of age (median, 9 months). All specimens contained abundant alveolar macrophages, indicating good recovery of alveolar contents. Clinically significant information was obtained in 17 (85%) cases, and no patient required an open lung biopsy. In conclusion, nonbronchoscopic bronchoalveolar lavage is a valuable method for obtaining alveolar contents in children with small AA that preclude the use of an FOB, and it obviates the need for open lung biopsy in many patients. This technique could be used as a research tool for measuring constituents of alveolar contents in infants and small animals.  相似文献   
85.
Ostial PV Isolation:   总被引:2,自引:0,他引:2  
Pulmonary vein (PV) isolation by elimination of spike potentials has been reported to cure drug refractory atrial fibrillation. Because of the heterogenous morphology of the PVs, sequential electroanatomic reconstruction of the PVs was performed in 39 patients (group A), who underwent subsequent PV isolation by interruption of all conductive myocardial fibers by distinct RF current applications using a "lasso" approach. In group B (157 patients), only biplane two-dimensional fluoroscopy was performed to guide the diagnostic and the ablation catheters. After reprocedures (in 7% of patients in group A and 22% of group B), which depicted a recurrence of a spike potential inside or at the ostium of  >1 previously isolated PV in all restudied patients, stable sinus rhythm was documented in 69% of patients in group A and 60% of patients in group B. Reasons for the relapse of the previously eliminated spike potentials include a temporary ablation effect and a too distal interruption of the conducting myocardial fiber. Detailed knowledge of the individual three-dimensional morphology enhanced the clinical success rate of PV isolation but is time-consuming using CARTO   (8.0 ± 1.7 vs 5.0 ± 1.6, P < 0.001)   . Further technical improvement to fuse the individual three-dimensional anatomy and the electrophysiological markers to a composed "electroanatomic" map may overcome this limitation in the future. (PACE 2003; 26[Pt. II]:1624–1630)  相似文献   
86.
Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the ProbeTM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful ProbeTM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.  相似文献   
87.
The case describes a 38-year-old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed.  相似文献   
88.
Following injections of 3H-leucine and 35S-methionine in the caudal half of the medial accessory olive, labeled climbing fibers were found contralateral to the injection site in the sagittal A-zone of the cerebellar vermis and in the fastigial nucleus. Labeling in the fastigial nucleus was analyzed with ultrastructural autoradiography. Labeled boutons of climbing fibers were found in the neuropil but never on somata. They contain spherical vesicles and occasionally some dense core vesicles in an electron-lucent matrix. The terminals of climbing fiber collaterals in the fastigial nucleus resemble climbing fiber terminals in the molecular layer with respect to their internal ultrastructural characteristics.  相似文献   
89.
In this study, antiserum raised against an insect myotropic peptide, leucokinin I (DPAFNSWGamide), was: used for mapping leucokinin-like immunoreactive (LK-LI) neurons in the gastropod mollusc, Helix pomatia. Immunocytochemistry performed on both whole-mounts and cryostat sections demonstrated LK-LI neurons in all ganglia of the central nervous system (CNS), except the visceral ganglion. Altogether about 700 immunolabelled neurons have been found, with nearly one-half (46%) in the cerebral ganglia. A large proportion of the LK-LI neurons have small cell bodies and are likely to be interneurons. The most prominent LK-LI cell group is represented by the entire neuron population of the mesocerebri, which is the major source of a thick fiber bundle system, encircling and innervating the whole CNS. One single LK-LI giant neuron was found, which is located in the left pedal ganglion and is termed GLPdLKC (giant left pedal leucokinin immunoreactive cell). This cell has not been identified previously. The ganglion neuropils are heavily innervated by varicose LK-LI fiber arborizations. Some integrative centers, such as the medullary neuropil of the procerebri, reveal an extreme density of LK-LI innervation. All major peripheral nerves contain a large number of LK-LI axons, and LK-LI innervation is found in the musculature of different peripheral organs (buccal mass, lip, tentacles, oviduct, intestine). Among the peripheral organs investigated, the intestine contains a rich varicose LK-LI network, composed of both intrinsic and extrinsic elements. Radioimmunoassay (RIA) demonstrates a very high content of LK-LI material in Helix ganglion extracts (about 50 pmol/CNS). This is the first report on the occurrence of a substance resembling the myotropic neuropeptide leucokinin I in a phylum outside arthropods. Based on our immunocytochemical observations, a role for leucokinin-like peptides in both central and peripheral regulatory processes in Helix is suggested. According to double-labelling experiments, only a small number of the LK-LI neurons are labelled with an antibody to the vertebrate tachykinin substance P.  相似文献   
90.
A new balloon electrode catheter (10 French) with five or six balloon electrodes placed on the cardiac side was developed for transesophageal atrial pacing and bipolar ECG recording. The diameter of the hemispheric electrodes is 6 mm and the length of the esophageal balloon is 10 cm. The transesophageal atrial pacing threshold was measured with the balloon electrode catheter by transesophageal programmed atrial stimulation (TPS) (n = 54). At the onset of TPS, the feeling, capture fn = 54), and pain voltage threshold (n = 6) were measured by increasing the amplitude of the pacing voltage during high rate bipolar atrial pacing and bipolar atrial ECG recording. In 38 TPS, the capture threshold was lower than the feeling threshold (n = 28). In 16 TPS, the capture threshold was higher than the feeling threshold. In conclusion, painless atrial pacing and excellent ECG recording can be achieved with a multipolar esophageal balloon electrode catheter with a low pacing voltage amplitude and a high P wave amplitude.  相似文献   
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