全文获取类型
收费全文 | 15656篇 |
免费 | 781篇 |
国内免费 | 56篇 |
专业分类
耳鼻咽喉 | 97篇 |
儿科学 | 480篇 |
妇产科学 | 285篇 |
基础医学 | 2147篇 |
口腔科学 | 315篇 |
临床医学 | 1197篇 |
内科学 | 3867篇 |
皮肤病学 | 247篇 |
神经病学 | 1511篇 |
特种医学 | 729篇 |
外科学 | 2138篇 |
综合类 | 45篇 |
一般理论 | 1篇 |
预防医学 | 741篇 |
眼科学 | 141篇 |
药学 | 1086篇 |
中国医学 | 19篇 |
肿瘤学 | 1447篇 |
出版年
2023年 | 74篇 |
2022年 | 166篇 |
2021年 | 332篇 |
2020年 | 199篇 |
2019年 | 293篇 |
2018年 | 335篇 |
2017年 | 278篇 |
2016年 | 299篇 |
2015年 | 314篇 |
2014年 | 462篇 |
2013年 | 609篇 |
2012年 | 907篇 |
2011年 | 993篇 |
2010年 | 562篇 |
2009年 | 511篇 |
2008年 | 841篇 |
2007年 | 872篇 |
2006年 | 760篇 |
2005年 | 738篇 |
2004年 | 689篇 |
2003年 | 654篇 |
2002年 | 619篇 |
2001年 | 418篇 |
2000年 | 429篇 |
1999年 | 437篇 |
1998年 | 166篇 |
1997年 | 127篇 |
1996年 | 123篇 |
1995年 | 93篇 |
1994年 | 102篇 |
1993年 | 93篇 |
1992年 | 281篇 |
1991年 | 265篇 |
1990年 | 273篇 |
1989年 | 256篇 |
1988年 | 192篇 |
1987年 | 165篇 |
1986年 | 187篇 |
1985年 | 214篇 |
1984年 | 125篇 |
1983年 | 101篇 |
1982年 | 71篇 |
1981年 | 49篇 |
1979年 | 109篇 |
1977年 | 57篇 |
1976年 | 56篇 |
1975年 | 55篇 |
1974年 | 47篇 |
1973年 | 58篇 |
1971年 | 50篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献
42.
Laparoscopic bile duct injuries. Risk factors, recognition, and repair. 总被引:18,自引:0,他引:18
R L Rossi W J Schirmer J W Braasch L B Sanders J L Munson 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(5):596-601; discussion 601-2
Records of 11 patients undergoing biliary reconstruction after laparoscopic cholecystectomy are reviewed. Ductal injuries resulted from failure to define the anatomy of Calot's triangle. Risk factors include scarring, acute cholecystitis, and obesity. Presenting findings included anorexia, ileus, failure to thrive, pain, ascites, and jaundice. All patients required hepaticojejunostomies, which were multiple and above the hepatic bifurcation in four patients. Given the extensive nature of these injuries and the frequent need for intrahepatic anastomosis and early stenosis of repairs by referring physicians, we recommend reconstruction be undertaken by an experienced hepatobiliary surgeon. To avoid injuries, a greater appreciation of risk factors and anatomic distortion and variance and strict adherence to principles of dissection and identification of anatomic structures are suggested. The use of cholangiography and a low threshold for conversion to the open procedure are advised. 相似文献
43.
44.
Self-efficacy in weight management 总被引:10,自引:0,他引:10
M M Clark D B Abrams R S Niaura C A Eaton J S Rossi 《Journal of consulting and clinical psychology》1991,59(5):739-744
Self-efficacy is an important mediating mechanism in advancing understanding of the treatment of obesity. This study developed and validated the Weight Efficacy Life-Style Questionnaire (WEL), improving on previous studies by the use of clinical populations, cross-validation of the initial factor analysis, exploration of the best fitting theoretical model of self-efficacy, and examination of change in treatment. The resulting 20-item WEL consists of five situational factors: Negative Emotions, Availability, Social Pressure, Physical Discomfort, and Positive Activities. A hierarchical model was found to provide the best fit to the data. Results from two separate clinical treatment studies (total N = 382) show that the WEL is sensitive to changes in global scores as well as to a subset of the five situational factor scores. Treatment programs may be incomplete if they change only a subset of the situational dimensions of self-efficacy. Theoretical and clinical implications are discussed. 相似文献
45.
M. Anselmino G. Zaninotto M. Costantini M. Rossi C. Boccu' D. Molena E. Ancona 《Surgical endoscopy》1997,11(1):3-7
Background: The Heller-Dor operation has recently been proposed for the treatment of esophageal achalasia even via a laparoscopic approach.
Methods: To measure the medium-term effectiveness of this new minimally invasive technique, an evaluation of pre- and postoperative
symptoms, esophagogram, endoscopic findings, esophageal manometry, and pH monitoring was prospectively designed in 43 patients
with primary esophageal achalasia. The mean clinical follow-up for all the patients is 12 months (range 3–43), while the mean
radiological follow-up is 11 months (range 1–23). Endoscopic data 1 year after surgery are currently available for 27 patients
(63%), whereas a 12-month (range 1–26) functional follow-up (including manometric and pH-monitoring studies of the esophagus)
is currently available for 35 patients (81.4%).
Results: No dysphagia was reported in 38 cases (88.4%); two (4.6%) complained of occasional swallowing discomfort which regressed
spontaneously; two (4.6%) had persistent dysphagia which regressed with pneumatic dilatation. One patient (2.8%) reported
mild occasional dysphagia after a 1-year asymptomatic period. Preoperatively, esophagograms showed an average maximum diameter
of 40.6 ± 9.1 mm which decreased to 24.1 ± 6.0 mm after operation. Mean lower esophageal sphincter (LES) resting and residual
pressures decreased significantly from 28.6 ± 10.7 mmHg to 8.8 ± 4.1 mmHg and from 17.0 ± 9.7 mmHg to 4.7 ± 4.0 mmHg, respectively
(p < 0.0001). These effects on esophageal diameter and LES function seem to persist over time. The complete absence of any peristaltic
contractions recorded preoperatively in all cases remained unchanged after surgery in all but four patients. However, this
rare recovery of peristalsis proved to be transient, and patients revealed a manometric impairment of their esophageal body
function, but without complaining of dysphagia. Twenty-four-hour pH monitoring showed abnormal gastroesophageal reflux episodes
in two (5.7%) of the 35 patients who were monitored: one was asymptomatic; the other had heartburn and endoscopically demonstrated
grade II esophagitis.
Conclusions: Laparoscopic Heller-Dor operation achieves excellent medium-term results which, together with the already-demonstrated advantages
of a minimal surgical trauma and rapid convalescence, validate the use of such a minimally invasive approach to treat patients
with primary achalasia of the esophagus.
Received: 19 March 1996/Accepted: 15 May 1996 相似文献
46.
Manjunath S. Vadmal Mario B. Rossi Saul Teichberg Steven I. Hajdu 《Pediatric and developmental pathology》1998,1(3):230-233
Juxtaoral organs known as organs of Chievitz are intramuscular embryonic structures found close to the angle of the mandible
near the insertion of the pterygomandibular raphae. They are considered of neuroepithelial origin with no known function.
We describe the first tumor of the organ of Chievitz which presented intraorally in a child. Immunohistochemically, the Chievitz
nests showed positive reaction for vimentin, cytokeratins, and epithelial membrane antigen and ultrastructurally demonstrated
cytoplasmic processes and intermediate filament bundles. These observations, together with light microscopic features, suggest
that the epithelial nests of the organ of Chievitz are meningothelial rather than neuroepithelial.
Received December 18, 1996; accepted March 13, 1997. 相似文献
47.
Further phenotypic evidence that nodular, lymphocyte-predominant Hodgkin's disease is a large B-cell lymphoma in evolution 总被引:4,自引:0,他引:4
S M Chittal C Alard J F Rossi T al Saati A Le Tourneau J Diebold G Delsol 《The American journal of surgical pathology》1990,14(11):1024-1035
Five cases of nodular, lymphocyte predominant Hodgkin's disease (nLP HD), in which an association with (n = 3) and transformation to (n = 2) large cell lymphoma (LCL) were found, were studied with monoclonal antibodies against B-, T-, and Reed-Sternberg (R-S) cell-associated antigens and epithelial membrane antigen (EMA) on paraffin sections. Both lymphocytic (L) and histiocytic (H) cells of nLP HD and lymphoma cells of LCL expressed multiple B-cell-associated antigens (detected by LN-1/CDw75, L26, MB2, DBB.42, DBA.44, DND.53, DNA.7 antibodies) but did not react with antibodies against T-cell-associated (MT1, UCHL1/CD45RO) (one exception for CD45RO in LCL) and R-S cell-associated (Leu-M1/CD15, Ber-H2/CD30) antigens. EMA was expressed by L and H cells in all cases and conserved in LCL cells, emphasizing the frequent expression of EMA by the diagnostic cells of nLP HD. An antibody (BNH9) against blood group-related antigens (H and Y oligosaccharide antigens) that does not normally react with lymphoid cells was found to be reactive with few L and H cells in two of five and most LCL cells in four of five cases. The finding might be indicative of abnormal activation of lymphoid cells. The data reinforce current implications that nLP HD is a B-cell malignancy in evolution and that it is not truly representative of Hodgkin's disease in terms of biological and clinical behavior. 相似文献
48.
R Roversi C Rossi S Ricci M C Galaverni A Teodorani P Gambari G Gardini S Boriani A Corinaldesi 《La Radiologia medica》1989,78(1-2):79-88
The authors report their 4-year (1984-1988) experience with TCE in the treatment of primary sacral benign/malignant and vascular bone tumors, after similar preliminary studies on aneurysmal bone cysts. Eleven patients were treated, for a total of 21 procedures: in 85% of the eight cases of palliative embolization, multiple instrumental approaches were needed for late revascularization, up to four consecutive embolizations in the same patients. Severe complications were observed in 19% of the procedures, due to arterial catheterization and/or instrumental maneuvers, but in none of them was surgery required. Technical results--i.e. devascularization of the mass--were optimal/suboptimal in all cases at the end of multiple procedures in the same patient: in 7/8 patients treated for palliation, however, the treatment was repeated, the late venous DSA angiographic control showing recanalization of the great vessels surrounding the lesion and/or revascularization through collateral channels. The analysis of morphological and clinical results (with reference to pain relief, dimension of the mass, and calcification at CT follow up) showed a complete pain relief in 100% of the patients treated preoperatively for palliation. The dimension of the mass was reduced in 12.5% of the cases treated for palliation, and recalcification was demonstrated on CT in 12.5% of cases. In 25.5% the mass had increased in size and in 62.5% its dimensions were unchanged. Effective pain relief was always obtained in the cases treated preoperatively. Thus, in our experience TCE of expansive lesions of the sacral bone can be considered as an effective therapeutical choice, with special reference to pain relief, for use in all inoperable cases, and as a preoperative treatment to minimize blood loss at surgery. Still, embolization materials are not completely satisfying: many of them are expensive, difficult to use and cannot be trusted to permanently occlude the vessels, which forces to intervene more than once to obtain optimal clinicomorphological results. As for malignant lesions, chemo-embolization with cytostatic substances should be used to improve the efficacy of the method. However, even through such negative judgements can be expressed on TCE, both technical and clinical results have been, in our experience, quite satisfactory, which calls for optimization of the methodology. 相似文献
49.
Giancarlo Flati Donato Flati Barbara Porowska Giorgio Rossi Sandro Francavilla Emanuele Santoro M. Carboni 《Microsurgery》1993,14(9):628-633
Circumferential choledochoplasties with vascular grafts have rarely been attempted either experimentally or in clinical practice. In this study, choledochoplasties using autologous venous and arterial grafts were performed in rats. Sixty-four rats were randomly selected into five treatment groups: A) venous interpositional graft replacement of a choledochus gap without a stent; B) venous graft with prolene stent; C) venous graft with polyethylene stent; D) arterial graft; E) a control group with simple resection between ligatures in the choledochus. The operative mortality in treatment groups B, C, D, and E, was 0, and 13% in group A. At 12 weeks follow-up, all the rats in group E had died, whereas, 52.2% (P <.05) of the rats in group A, 30% of the rats in group B, 57% of the rats in group C, and 92.8% of the rats in group D survived treatment. Surviving animals were sacrificed at 3 months for further examination. The morphology and caliber of the common bile duct of these rats were normal in 25% of the rats in group A, 33% of the rats in group B, 25% of the rats in group C, and 84.6% of the rats in group D. Proximal dilations were found in the rats presenting with abnormal morphology. The dilations were less marked in the group treated by arterial choledochoplasties. Laboratory and clinical cholestatic parameters were within normal ranges in the presence of common bile duct dilations less than four times the normal duct caliber. Electron microscopic examination of the venous and arterial graft at 3 months follow-up revealed a fibrous ring composed of collagen fibers, fibroblasts, and remnants of elastic fibers. Regenerated ductal epithelium encompassed both types of grafts. Epithelialization was more pronounced in venous grafts as compared to arterial grafts. Biliary epithelium was able to colonize the venous grafts and resume cell specialization and function as in normal biliary epithelium. The most satisfactory results were obtained using venous grafts with stents or by using arterial grafts. © 1993 Wiley-Liss Inc. 相似文献
50.
A. W. Shahrom P. Vanezis R. C. Chapman A. Gonzales C. Blenkinsop M. L. Rossi 《International journal of legal medicine》1996,108(4):194-200
A facial image was reconstructed from the skull, part of a complete skeleton found in woodland, of a male person who had hanged himself from a tree. In addition, video superimposition was carried out with antemortem photographs of a person suspected of being the victim, and a good match was obtained. In a further case, a cheaper video-transparency superimposition was carried out, with identity later being confirmed on the basis of dental records. The techniques and the problems encountered are discussed. According to our experience, 3D computer reconstruction and video superimposition have a useful role in the process of identification, particularly in the early stages of an investigation and when other more definitive methods may not be available. 相似文献