全文获取类型
收费全文 | 40757篇 |
免费 | 3437篇 |
国内免费 | 187篇 |
专业分类
耳鼻咽喉 | 368篇 |
儿科学 | 1185篇 |
妇产科学 | 732篇 |
基础医学 | 5581篇 |
口腔科学 | 524篇 |
临床医学 | 4654篇 |
内科学 | 9067篇 |
皮肤病学 | 902篇 |
神经病学 | 4138篇 |
特种医学 | 1442篇 |
外国民族医学 | 1篇 |
外科学 | 6262篇 |
综合类 | 265篇 |
一般理论 | 34篇 |
预防医学 | 3425篇 |
眼科学 | 571篇 |
药学 | 2424篇 |
中国医学 | 78篇 |
肿瘤学 | 2728篇 |
出版年
2023年 | 164篇 |
2022年 | 337篇 |
2021年 | 806篇 |
2020年 | 613篇 |
2019年 | 1073篇 |
2018年 | 1239篇 |
2017年 | 975篇 |
2016年 | 971篇 |
2015年 | 1231篇 |
2014年 | 1502篇 |
2013年 | 2116篇 |
2012年 | 2705篇 |
2011年 | 2864篇 |
2010年 | 1827篇 |
2009年 | 1678篇 |
2008年 | 2505篇 |
2007年 | 2633篇 |
2006年 | 2457篇 |
2005年 | 2553篇 |
2004年 | 2407篇 |
2003年 | 2358篇 |
2002年 | 2443篇 |
2001年 | 376篇 |
2000年 | 313篇 |
1999年 | 403篇 |
1998年 | 471篇 |
1997年 | 420篇 |
1996年 | 345篇 |
1995年 | 381篇 |
1994年 | 312篇 |
1993年 | 283篇 |
1992年 | 212篇 |
1991年 | 234篇 |
1990年 | 189篇 |
1989年 | 172篇 |
1988年 | 170篇 |
1987年 | 179篇 |
1986年 | 158篇 |
1985年 | 163篇 |
1984年 | 172篇 |
1983年 | 128篇 |
1982年 | 191篇 |
1981年 | 178篇 |
1980年 | 163篇 |
1979年 | 105篇 |
1978年 | 109篇 |
1977年 | 96篇 |
1976年 | 78篇 |
1975年 | 70篇 |
1972年 | 73篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
K Jean Cotterman 《Journal of human lactation》2004,20(2):227-237
Successful breastfeeding requires efficient milk transfer through the nipple-areolar complex, which includes subareolar tissue. Subareolar tissue resistance increases during engorgement, when expanded circulation and excess interstitial fluid compete for space with increasing milk volumes. Physiologic and iatrogenic events often combine to produce distortion of breast anatomy. Resulting latch difficulty, delayed milk ejection reflex, poor milk transfer, pain, and nipple damage discourage many mothers. The rationale and technique for a simple intervention developed in practice are described: reverse pressure softening (RPS) before latching significantly reduces resistance of subareolar tissue, temporarily freeing it to interact more efficiently with the baby's mouth. RPS also triggers the milk ejection reflex promptly. The health care provider can perform RPS or teach the mother and her significant others, even by telephone. 相似文献
93.
Gérard Brunel Edmond Benqué Frédéric Elharar Catherine Sansac Jean François Duffort Pierre Barthet Eric Baysse Neal Miller 《Clinical oral implants research》1998,9(5):303-312
The aim of the present study was to evaluate the combined application of different bioabsorbable materials for healing of residual peri‐implant defects after placement of non‐submerged implants into fresh extraction sockets. Second and third mandibular premolars were extracted from 10 Beagle dogs, the coronal part of the distal sockets were surgically enlarged and this was followed by immediate placement of specially designed hollow‐screw non‐submerged dental implants. For each animal, the coronal peri‐implant defects were further treated with one of the 4 following procedures: 1) no treatment, control site: 2) grafting with porous hydroxyapatite (HA); 3) collagen membrane tightly secured around the implant and over the defect and 4) grafting with HA covered with a collagen membrane. After 16 weeks of healing, specimens were removed from the mandibule and prepared for a histomorphometric evaluation. The bone-to-implant contact length (BIC) was measured and compared amongst the different treatment modalities. In the defect area, the irregular bone regeneration was similar between all the treatment procedures ( P >0.10). In the sites covered with a collagen membrane alone, the total BIC (47%) was greater than in control sites (28.7%. P <0.05) or sites grafted with HA (22.2%, P <0.02). Total BIC in sites treated with the HA‐membrane combination (43%) was only significantly different from sites treated with HA ( P <0.10). It is concluded that the use of bioabsorbable materials results in a limited increase of osseointegration when used in conjunction with immediate placement of non-submerged implants, although the principle of the one stage surgical approach can be maintained. 相似文献
94.
Gustave Savourey Nathalie Garcia Jean Pierre Caravel Claude Gharib Nadine Pouzeratte Serge Martin Jacques Bittel 《European journal of applied physiology》1997,77(1-2):37-43
High altitude residence is known to modify body biochemistry and hormone status. However, the effects of such a sojourn on these status observed at sea level both immediately and later after return are not as well established as are the effects of an intermittent acclimation. The aim of this study was therefore to investigate these changes. To achieve our objectives, nine subjects received intermittent acclimation at low pressure in a barometric chamber (8?h daily for 5 days, day 1 at 4500 m, day 5 at 8500 m) before an expedition to the Himalayas. Hormonal and biochemical changes were studied using samples of venous blood taken at sea level before and after acclimation, after return from the expedition and 1 and 2 months after descent. Concentrations of thyroid hormones, adrenaline, noradrenaline (NA), hormones of hydromineral metabolism (aldosterone, renin, arginine vasopressin, atrial natriuretic peptide) as well as prolactin, cortisol, insulin and endothelin 1 were measured. Biochemical measurements made were plasma osmolality, and concentrations of glucose, total cholesterol, total proteins, pre-albumin, transferrin, complement 3C, apolipoproteins A1 and B and serum iron. Acclimation induced no alteration in hormone (except for NA with increases of about 1.5, fold P<0.05) and biochemistry data. After the expedition, hormone responses were characterized by a higher total triidothyronine concentration (+18%, P<0.05) while other hormones did not vary. A linear relationship was found between thyroid-stimulating-hormone and body mass changes after the expedition (r=0.67, P<0.05). The observed increased concentrations of plasma proteins and total cholesterol (P<0.05) could be related to the restoration of lean body mass. At 1 and 2 months after return, no changes in hormones were observed but a significant decrease in transferrin concentration was noticed. The higher serum iron concentration reported after 1 month (P<0.05) could have been the result of a physiological haemolysis. It was concluded that both acclimation and the expedition in the Himalayas affected hormone status and body biochemistry status even though the observed changes were slight and rapidly reversed. 相似文献
95.
R R Pascal G Hertzler S Hunter S Goldschmid 《The American journal of surgical pathology》1990,14(7):694-697
High-grade dysplasia was found to extend to an area of pseudoinvasion in the submucosa of a colonic adenoma mimicking invasive carcinoma. The presence of both benign and cytologically malignant epithelium and residual foci of lamina propria among the submucosal glands distinguishes this entity from adenocarcinoma arising in an adenomatous polyp. 相似文献
96.
Jean Arundale 《British Journal of Psychotherapy》2004,20(4):453-454
97.
The purpose of this cross-sectional study was to determine whether measures on a selected groups of visual and psychomotor variables distinguished between groups of elite, intermediate and novice table tennis players. The variables included commonly of Melbourne measured clinical functions such as static visual acuity, extent of visual field and oculomotor balance and more experimental visual tasks such as recognition of, peripheral targets, saccadic latency and dynamic visual acuity. Psychomotor performance was assessed by measures of simple reaction time, choice response time and hand movement time. Although elite level competitors had significantly better dynamic visual acuity, a wider visual field and superior recognition of peripheral targets compared to less skilled competitors, the magnitude, or practical significance of these differences was not great and individually accounted for less than 5 per cent of population variance. Elite competitors had significantly faster psychomotor responses than novice players with die skill variables individually accounting for between 21 per cent and 62 per cent of population variance in psychomotor performance. These results indicate that the psychomotor parameters could be a useful part of a test battery for talent identification amongst table tennis players. 相似文献
98.
99.
Weeranuj Yamreudeewong Pharm.D. James V. Johnson M.D. Thomas G. Cassidy M.D. Jean T. Berg R.N. 《Pharmacotherapy》1996,16(6):1159-1165
Warfarin is a commonly used oral anticoagulant that is usually initiated after the definitive diagnosis of a certain thromboembolic disorder or disease. Warfarin therapy will usually be prescribed for 6–12 weeks or more, and some patients may continue therapy throughout life, depending on the type of thromboembolic disorder. Major problems associated with warfarin therapy include adverse effects such as bleeding complications and drug-drug or drug-food interactions. In addition, thromboembolic complications may occur due to subtherapeutic dosages of warfarin. The laboratory reference standards for monitoring warfarin therapy are the prothrombin time (PT) and the International Normalized Ratio (INR). While both the PT or INR will reflect the clinical response in the patient, results reported as INR values have been shown to be more accurate than those reported as PT values. Thirty-two patients were enrolled in this study. Our objectives were to compare INR values measured by both the Coumatrak and conventional laboratory method, and to demonstrate the effects of pharmacist intervention on managing patients receiving warfarin therapy. Results from our study reveal that INR monitoring by Coumatrak is similar to the conventional laboratory method. In addition, our study indicates that patients receiving warfarin therapy can be monitored and managed effectively by pharmacists. 相似文献
100.
Aneurysm of the abdominal aorta in an eighteen-month-old child 总被引:1,自引:0,他引:1
Jean Olivier Defraigne MD Jean Pierre Paquot MD Etienne Creemers MD Raymond MD Limet 《Annals of vascular surgery》1988,2(2):193-195
We report the case of an infected aneurysm of the abdominal aorta in a 18 month-old child, discovered by routine palpation of the abdomen during hospitalization for pneumonia. Ultrasonography and arteriography showed a 6 cm aneurysm of the abdominal aorta beginning distal to the renal arteries which occluded the right common Iliac artery. The aneurysm was treated by interposing a 6 mm Gore-Tex graft between the infrarenal aorta and the aortic bifurcation. Pathologic examination of the aneurysmal wall demonstrated a leukocytic Infiltrate and the presence of encapsulated Gram positive organisms. Arterial aneurysms are exceedingly rare in children. Their etiology is varied: infection, connective tissue disease, trauma, inflammatory arterial disease or other rare diseases such as tuberous sclerosis, neurofibromatosis, or Beçhet’s disease. 相似文献