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91.
Camp S. J. Stevenson V. L Thompson A. J. 《世界核心医学期刊文摘》2006,2(6):58-59
有关多发性硬化症患者认知功能的纵向研究很少,并且上述研究的结果也不明确,迄今尚无专门关于原发进行性多发性硬化症(PPMS)病例系列的连续神经心理学资料。横断面分析揭示,PPMS患者的认知功能与磁共振成像(MRI)参数之间显著相关。本研究持续2年时间对来源于5个欧洲中心的99例PPMS患者的认知功能和MRI改变进行探讨。采用简易可重复问卷(一种推理能力测试)和抑郁量表每隔12个月对患者进行评估,同时在每个时间点对T1低信号负荷、T2损伤负荷和部分脑体积的MRI参数进行测算。基线和2年时患者的平均认知功能得分间无显著差异。然而,1/3患者的单独测试得分表现出绝对的认知功能下降。研究结果提示,纳入研究时的初始认知状态是2年后认知能力的一个可靠预测指标。认知功能改变和MRI改变间仅有少数几项指标显著相关,值得一提的是T1低信号负荷与2项注意力测试任务相关(r=-0.266,P=0.017;r=-0.303,P=0.012),可能是由多种因素造成认知功能和MRI参数间的这种弱相关。 相似文献
92.
93.
D A Quinn B T Thompson M L Terrin J H Thrall C A Athanasoulis K A McKusick P D Stein C A Hales 《JAMA》1992,268(13):1689-1696
OBJECTIVE. The aim of this study was to compare, in women and men suspected of pulmonary embolism, the frequency, risk factors, diagnosis, and presentation of pulmonary embolism as well as the accuracy of the ventilation/perfusion scan (V/Q scan) as a diagnostic tool. DESIGN. Data were collected during a prospective study (the Prospective Investigation of Pulmonary Embolism Diagnosis) to establish the accuracy of the V/Q scan compared with pulmonary angiograms. SETTING. Six tertiary medical centers in Massachusetts, Michigan, Connecticut, Pennsylvania, and North Carolina. PARTICIPANTS. Patients suspected of pulmonary embolism for whom a request was made for a V/Q scan or pulmonary angiogram (496 women and 406 men). RESULTS. Women 50 years old and under had a decreased frequency of pulmonary embolism compared with men of that age (16% vs 32%), but there was no difference in patients over 50 years old (Breslow-Day test, P less than .01). Risk factors for pulmonary embolism, the usefulness of the V/Q scan, and 1-year mortality were not different for women and men. Estrogen use in women was not associated with an increased frequency of pulmonary embolism, except in women using oral contraceptives who had undergone surgery within 3 months; four of five (80%) had emboli compared with four of 28 (14%) age-matched surgical patients not using estrogens (P less than .01). CONCLUSION. Women 50 years old and under (even young women using oral contraceptives) who were suspected of having pulmonary emboli and were enrolled in the Prospective Investigation of Pulmonary Embolism Diagnosis study had a smaller frequency of pulmonary embolism than men of that age, The risk factors for pulmonary embolism were the same for women and men, except that women using oral contraceptives had an increased risk of pulmonary embolism following surgery. Although the V/Q scan was a useful tool in the preliminary evaluation for pulmonary embolism in these women, a pulmonary angiogram was often needed for accurate diagnosis. 相似文献
94.
The response of Aplysia abdominal ganglion neuron L2 to the molluscan neuroactive peptide Phe-Met-Arg-Phe-NH2 (FMRFamide) was studied in voltage-clamp experiments. In all of the experiments, focal application of the peptide to the soma activated an inward rectifier current and reduced the apparent amplitude of the transient K current, IA. In a few cells, Na and K currents were activated in addition to these effects. Voltage-jump experiments were performed to study the ionic dependence, kinetics, and voltage dependence of the inward rectifier. Inward rectification increased exponentially during hyperpolarizing pulses and recovered exponentially on return to the resting potential. The reversal potential was variable, but was near -40 mV at the beginning of experiments. Inward rectification was insensitive to changes in external Na, Ca, or K concentration, but lowering the external Cl concentration had complicated effects on current amplitude. When KCl microelectrodes were used, perfusion with low-Cl external saline increased the amplitude of the peptide-dependent inward rectifier and shifted its reversal potential to a more positive voltage. With KAc microelectrodes, perfusion with low-Cl saline reduced the amplitude of the current. Inward rectification increased when a KAc microelectrode was withdrawn and replaced with a low-resistance KCl electrode, even when there was no measurable change in reversal potential. These results suggest that the FMRFamide-dependent inward rectifier is a Cl current that, like the current described by Chesnoy-Marchais (1982, 1983), is modulated by intracellular Cl. FMRFamide reduced the apparent amplitude of IA without affecting the voltage dependence of IA activation or inactivation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
96.
Definitive therapy for hyperhidrosis is sympathectomy. The authors have used a posterior approach to perform 36 dorsal sympathectomies for upper extremity hyperhidrosis in 18 patients (12 female, 6 male). All 18 patients suffered from excessive sweating of the upper extremity (17 palmar, 1 axillary) that caused significant psychological and occupational problems. Eleven patients (61.1%) had lower extremity involvement as well. For all 18 patients conservative medical treatment had failed. Bilateral operations were performed, via a posterior extrapleural approach, through the bed of the third rib. All 36 limbs were relieved of excess sweating. There were no deaths and only two minor wound complications. In no patient did Horner's syndrome develop. Long-term follow-up did not reveal any recurrence of hyperhidrosis. Two patients did complain of compensatory hyperhidrosis of the lower extremities. Dorsal sympathectomy was effective in all of the patients with upper extremity hyperhidrosis in this series. The posterior approach is technically simple, allows simultaneous bilateral operations, and is associated with only infrequent minor complications. 相似文献
97.
98.
Presentation of abdominal tuberculosis to general surgeons. 总被引:2,自引:0,他引:2
M J Underwood M M Thompson R D Sayers A W Hall 《The British journal of surgery》1992,79(10):1077-1079
Abdominal tuberculosis (TB) continues to give rise to diagnostic and therapeutic challenges. A total of 24 patients with abdominal TB who presented to general surgeons over a 9-year period have been reviewed. Most (92 per cent) of these patients were Asian; only one had a past history of pulmonary TB. The most common presenting complaint was abdominal pain in 21 patients (88 per cent) with the associated symptoms of weight loss in 18 (75 per cent), anorexia in 15 (62 per cent) and night sweats in 13 (54 per cent). A tissue diagnosis was obtained in 18 patients (75 per cent) and 17 patients (71 per cent) underwent laparotomy. These results show that the diagnosis of abdominal TB is still difficult to establish, and that many patients undergo laparotomy despite the existence of less invasive diagnostic procedures. 相似文献
99.
100.
Stimulation of the human motor cortex through the scalp 总被引:24,自引:0,他引:24