全文获取类型
收费全文 | 2323篇 |
免费 | 100篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 93篇 |
妇产科学 | 11篇 |
基础医学 | 240篇 |
口腔科学 | 34篇 |
临床医学 | 174篇 |
内科学 | 501篇 |
皮肤病学 | 56篇 |
神经病学 | 120篇 |
特种医学 | 106篇 |
外科学 | 380篇 |
综合类 | 47篇 |
预防医学 | 61篇 |
眼科学 | 211篇 |
药学 | 201篇 |
1篇 | |
中国医学 | 5篇 |
肿瘤学 | 186篇 |
出版年
2022年 | 11篇 |
2021年 | 30篇 |
2020年 | 16篇 |
2019年 | 25篇 |
2018年 | 36篇 |
2017年 | 20篇 |
2016年 | 27篇 |
2015年 | 23篇 |
2014年 | 48篇 |
2013年 | 68篇 |
2012年 | 86篇 |
2011年 | 100篇 |
2010年 | 58篇 |
2009年 | 41篇 |
2008年 | 67篇 |
2007年 | 93篇 |
2006年 | 105篇 |
2005年 | 103篇 |
2004年 | 94篇 |
2003年 | 92篇 |
2002年 | 75篇 |
2001年 | 92篇 |
2000年 | 119篇 |
1999年 | 111篇 |
1998年 | 40篇 |
1997年 | 43篇 |
1996年 | 38篇 |
1995年 | 37篇 |
1994年 | 35篇 |
1993年 | 33篇 |
1992年 | 75篇 |
1991年 | 69篇 |
1990年 | 79篇 |
1989年 | 69篇 |
1988年 | 51篇 |
1987年 | 44篇 |
1986年 | 33篇 |
1985年 | 30篇 |
1984年 | 30篇 |
1983年 | 19篇 |
1979年 | 19篇 |
1978年 | 12篇 |
1977年 | 10篇 |
1975年 | 13篇 |
1974年 | 11篇 |
1973年 | 10篇 |
1972年 | 10篇 |
1969年 | 11篇 |
1968年 | 10篇 |
1967年 | 9篇 |
排序方式: 共有2436条查询结果,搜索用时 15 毫秒
1.
Substance P- and calcitonin gene-related peptide-immunofluorescent nerves in the repair of experimental bone defects 总被引:3,自引:0,他引:3
Summary Healing of an experimental bony defect in the rat's tibia was studied with an immunofluorescent technique to clarify when and where substance P (SP) and calcitonin gene-related peptide (CGRP) would develop. The normal tibia showed a few SP- and CGRP-immunofluorescent nerve fibres. In the experimental tibia, the number of these fibres increased on the 6th day after operation, reached a peak of proliferation on the 15th day and reverted to normal after the 24th day. The changes were associated with the development and decay of callus tissue suggesting that harmful stimuli from the injured site in a bone could be mediated by sensory nerves throughout the repair period. Most of the SP- and CGRP-immunofluorescence was seen near the vessels, frequently in the same nerve fibres. The SP- and CGRP-immunofluorescent nerves seemed to take part jointly in callus formation through the enhancement of local blood flow.
Résumé Le procesus de guérison d'une perte de substance osseuse expérimentale a été étudié sur le tibia du rat par immunofluorescence afin de déterminer quand et où la substance P (SP) et la calcitonine peptide d'origine génique (CGRP) se développeraient. Le tibia normal ne montre qu'un petit nombre de fibres nerveuses immunofluorescentes SP et CGRP. Dans le tibia d'expérimentation, les fibres nerveuses immunofluorescentes SP et CGRP augmentent en nombre à partir du 6ème jour, atteignent leur maximum de prolifération le 15ème jour et reviennent à l'état normal après le 24ème jour post-opératoire. Ces modifications sont étroitement associées au développement et à la disparition du cal, suggérant ainsi que les stimuli nocifs provenant de la lésion osseuse pourraient être inactivés par les nerfs sensitifs durant la période de réparation. En outre, la plus grande partie de l'immunofluorescence SP et CGRP a été observée à proximité des vaisseaux, souvent dans les mêmes fibres nerveuses. Il semble que les nerfs immunofluorescents SP et CGRP participent conjointement à la formation du cal en augmentant la vascularisation locale.相似文献
2.
Kanta Kishi Michiko Muramatsu Denan Jin Keiichi Furubayashi Shinji Takai Hiroshi Tamai Mizuo Miyazaki 《Hypertension research》2007,30(1):77-83
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries. 相似文献
3.
Yusuf K. Durlu Sei-ichi Ishiguro Akiko Yoshida Takezo Mito Makio Tsuchiya Makoto Tamai 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1990,228(1):44-48
We used morphological, biochemical and immunohistochemical methods to assess the response of Müller cells after experimental
lensectomy-vitrectomy in rabbits. We observed widened intercellular spaces between the Müller cells and nerve fibers of ganglion
cells, and increased electron opacity in the Müller cells of eyes injected with silicone oil. No apparent morphological changes
were detected in the Müller cells of air-injected eyes. The specific and total activities of Müller cell-marker enzymes (glucose
6-phosphatase and glutamine synthetase) showed an initial increase, followed by a decrease. Glial fibrillary acidic protein
immunoreactivity was not found in the Müller cells of the normal rabbit retina but was exhibited after surgery. Our results
showed that markers of Müller cells associated with glycogenolysis and/or gluconeogenesis, glutamate-glutamine cycle and cytoskeletal
protein metabolism were affected by the experimental lensectomy-vitrectomy. 相似文献
4.
We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc. 相似文献
5.
Venous drainage of a musculocutaneous graft was shown to be of importance for the prevention of necrosis and successful graft take. An experimental model was provided in which the iliolumbar veins were used as draining veins in creating musculocutaneous grafts 4 X 3 cm and 4 X 6 cm in size. In the study, it was demonstrated that necrosis could be prevented by preserving draining veins. The number and size of these veins were of some significance in the survival of the grafts. 相似文献
6.
7.
Kazuya Tamai MD PhD Minoru Yamato MD PhD 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1997,6(6):534
We studied 16 patients (18 shoulders) with frozen shoulders, 8 patients with subacromial impingement syndrome, and 3 healthy volunteers with dynamic magnetic resonance imaging enhanced with gadolinium diethylenetriaminepentaacetic acid. After intravenous contrast was administered, gradient-recalled echo images were obtained in the oblique coronal plane every 11 to 13 seconds for a total period of 4 to 5 minutes. The signal intensity was measured at the periphery of the glenohumeral joint and in the subacromial bursa. The coefficient of enhancement (percent signal increase per second) in the frozen shoulders was 1.33±0.43 (mean ± SD) for the glenohumeral joint and 0.89±0.47 for the subacromial bursa. These values were far greater than those in subacromial impingement syndrome or in the control group, indicating increased blood flow to the synovium in the frozen shoulders. No previous reports have shown a clinical measure related to the pathophysiology of this disease. 相似文献
8.
Ca-mediated stimulation of Cl secretion by reactive oxygen metabolites in human colonic T84 cells. 下载免费PDF全文
H Tamai T S Gaginella J F Kachur M W Musch E B Chang 《The Journal of clinical investigation》1992,89(1):301-307
Monochloramine (NH2Cl), a granulocyte-derived reactive oxygen metabolite (ROM), increases short-circuit current (Isc) in cultured T84 monolayers in a concentration-dependent manner up to nonlethal concentrations of 75 microM. Isc increases slowly after NH2Cl, reaching a peak value of 18 +/- 2 microA/cm2 20 min after addition. The Isc changes are persistent (lasting over 20-30 min), depend on medium Cl, and are inhibitable with bumetanide. 36Cl flux studies demonstrated that NH2Cl increases serosa-to-mucosa flux of Cl without changing mucosa-to-serosa flux, consistent with stimulation of electrogenic Cl secretion. Isc responses to NH2Cl, but not PGE2, are dependent on medium calcium. As demonstrated in fura-2-loaded T84 cells, NH2Cl increases free cytosolic calcium by influx of extracellular Ca2+ and by release of Ca2+ from endogenous stores. However, NH2Cl had no effect on phosphatidylinositol metabolism or cyclic nucleotide levels. We conclude that ROM directly stimulate electrolyte secretion, an effect in part mediated by increases in cytosolic Ca2+, possibly through increasing Ca2+ permeability of cellular membranes. 相似文献
9.
Biomechanics of the golf swing in players with pathologic conditions of the forearm, wrist, and hand
Golf is an activity generally stressful to the hands and wrists and particularly can produce increasing symptoms in players with underlying problems such as hand and wrist arthritis or tendinitis. The purpose of this study was to quantitate wrist motion and club head/ball impact force in subjects with pathologic conditions of the hand, wrist, or forearm, within a laboratory environment. A regular straight-handled golf club was compared to a new BioCurve handle design that has a 19 degrees ulnar bend. We measured and compared the effect of the two grips on wrist motion, club head velocity, ball impact force, ball impact location, and isometric torsional strength in 20 subjects who had a variety of upper extremity disorders. This data was then compared to data collected in an identical fashion from golfers without such conditions. The results of our study show that there were no differences related to club handle design on impact force or impact location, club head velocity, or club head path and face angle. Wrist kinematic differences were minimal between handle designs. The differences that were significant (P less than 0.05) centered around the decreased ulnar deviation of the left hand that resulted when subjects used the BioCurve handle design, which also allowed greater resistance to torque than the straight grip club. In addition to collecting objective data, we asked subjects for their opinions of the two grips. As a whole, the normal group and the group with pathologic conditions noted more comfort, improved grip, and less shock transmission with the BioCurve handle. 相似文献
10.
Summary. A man, 79 years of age, developed a malignant fibrous histiocytoma which arose in relation to a calcifying enchondroma of
the distal femur. Radiographs showed a fracture through an intensely calcified bony tumour with no bony destruction. The clinical
diagnosis was a dedifferentiated chondrosarcoma. Histology showed an anaplastic sarcoma with calcified tissue showing extensive
areas of necrosis and degeneration. No chondrosarcomatous foci were found.
Accepted: 9 November 1996 相似文献
Resumé. Nous rapportons le cas d’un homme de 79 ans, qui a développé un histiocytofibrome malin à partir d’un enchodrome calcifié du fémur distal. L’examen radiologique a montré une fracture au sein d’une tumeur très calcifiée sans association de destruction osseuse. Cette lésion apparaissait cliniquement être un chondrosarcome dédifférencié. Mais l’étude histologique a montré un sarcome anaplasique avec un tissu cartilagineux calcifié présentant des plages étendues de nécrose et de dégénérescence. Il n’y avait pas de foyer chondrosarcomateux visible.
Accepted: 9 November 1996 相似文献