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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
Shiro Oka Shinji Tanaka Iwao Kaneko Hiroyuki Kanao Kazuaki Chayama 《Digestive endoscopy》2007,19(Z1):S30-S33
Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future. 相似文献
62.
Toshihiko Imakiire Yuichi Kikuchi Muneharu Yamada Taketoshi Kushiyama Keishi Higashi Naomi Hyodo Kojiro Yamamoto Takashi Oda Shigenobu Suzuki Soichiro Miura 《Hypertension research》2007,30(7):635-642
The mechanisms of hypertensive nephrosclerosis are not fully understood. In experimental models of the disease, inflammatory reactions such as macrophage infiltration play an important role. In human hypertensive nephrosclerosis, however, there have been few studies examining the role of inflammation histologically. We investigated whether the number of infiltrating macrophages was increased in human hypertensive nephrosclerosis, and evaluated the effects of a blockade of the renin-angiotensin system on clinical and histological findings. We examined macrophage infiltration using immunohistochemistry in renal biopsy specimens obtained from 16 patients with hypertensive nephrosclerosis, 5 patients with IgA nephropathy, 5 patients with membranous nephropathy, and 5 patients with minimal change nephrotic syndrome. The number of infiltrating macrophages in glomeruli was significantly larger in the patients with hypertensive nephrosclerosis than in those with minimal change nephrotic syndrome. The patients with hypertensive nephrosclerosis were divided into groups based on their use of antihypertensive agents at the time of renal biopsy. We investigated the effects of antihypertensive agents on clinical findings, macrophage infiltration, and monocyte chemoattractant protein-1 expression. There was no difference in clinical findings between the hypertensive groups. The numbers of infiltrating macrophages and monocyte chemoattractant protein-1-positive cells in glomeruli were significantly smaller in patients treated with an angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker, whereas calcium channel blockers had no influence on histological findings. In conclusion, inflammation is involved in the progression of human hypertensive nephrosclerosis and the inflammatory process is inhibited by blocking the renin-angiotensin system. 相似文献
63.
Hatta Naohito MD PhD † Morita Reiji MD PhD Yamada Mizuki MD Takehara Kazuhiko MD PhD Ichiyanagi Kenji MD PhD ‡ Yokoyama Kunihiko MD PhD ‡ 《Dermatologic surgery》2005,31(3):327-330
BACKGROUND: Although there is lymphatic flow into the popliteal fossa from a skin tumor located in the lower leg, popliteal metastasis is extremely rare. Recently, sentinel lymph nodes outside traditional nodal basins have been identified. This study investigated the incidence of sentinel nodes in the popliteal region and the indication for biopsy. METHODS: Fourteen patients with various skin cancers involving the lower extremities (nine melanomas, four squamous cell carcinomas, and one sweat gland carcinoma) underwent lymphoscintigraphy and excision with sentinel lymph node biopsy. RESULTS: In all 14 patients, hot spots showed accumulation in the groin region. Five of 14 patients (36%) demonstrated popliteal sentinel nodes in addition to the inguinal nodes. Three of five popliteal sentinel nodes were histologically studied. A patient with acral melanoma demonstrated micrometastasis of melanoma cells in a popliteal node but not in the groin node. CONCLUSION: This study demonstrates that sentinel lymph nodes located in the popliteal fossa are frequently detected by lymphoscintigraphy and that biopsy should be performed if popliteal nodes are identified. 相似文献
64.
Novel SCN5A mutation (Q55X) associated with age-dependent expression of Brugada syndrome presenting as neurally mediated syncope. 总被引:1,自引:0,他引:1
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism. 相似文献
65.
Makiho Sekiuchi Kimimasa Nakabayashi Tomohumi Marumo Yoshihiro Arimura Akira Yamada 《Ryūmachi》2003,43(4):696-702
A 65-year old female, who had been suffered from rheumatoid arthritis, was admitted to our hospital because of fever, oral ulcers, perianal skin ulcers, petechiae in the both legs, hepatosplenomegaly and cervical lymphadenopathy. Her laboratory data showed severe anemia, leukocytopenia, and thrombocytopenia as well as low PT activity, prolonged APTT, decreased fibrinegen and elevated FDP. In addition to raised values of liver enzymes and triglyceride, marked elevation of several cytokines were found. IgM and IgG class antibodies to cytomegalovirus were demonstrated positive and their titers were 2.60 and 938.0, respectively. The study for the aspiration of bone marrow revealed hemophagocytosis of erythrocytes, leukocytes and thrombocytes. Based upon these findings, she was diagnosed as having hemophagocytic syndrome associated with cytomegalovirus infection. Steroid treatment inducing mini-pulse therapy was introduced to her and bought full recovery from the illness. The association of hemophagocytic syndrome to rheumatoid arthritis was reviewed in the literature and five cases were documented to have good prognosis with steroid treatment. 相似文献
66.
67.
Hirotsugu Yamada MD PhD Zoran B. Popovic MD PhD David O. Martin MD MPH Kenneth C. Civello MD MPH Don W. Wallick PhD 《Heart rhythm》2006,3(6):722-727
BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied. 相似文献
68.
Kenji Tsukada Shigeru Kobayashi Tatsuya Gotoh Naoki Asakage Masayuki Sekine Morio Sasaki Eiji Miyazaki Takahisa Suzuki Toshio Yamada Shu Hirai Shigetaka Yamazaki 《Digestive endoscopy》2006,18(1):55-58
A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented. 相似文献
69.
Shuro Yoshino Takayuki Matsumoto Koichi Kurahara Hiroyuki Kobayashi Mitsuo Iida Tadahiko Fuchigami 《Digestive endoscopy》2006,18(1):59-61
We present a 70‐year‐old man who had two episodes of melena during the preceding 8‐year period. He had a Dieulafoy‐like lesion in a diverticulum in the third portion of the duodenum. While emergency endoscopy revealed neither apparent blood nor clots around the diverticular orifice, there was a non‐bleeding vessel in the fundus of the diverticulum. The vessel ceased bleeding after argon plasma coagulation and, since then, the patient has not experienced bleeding. In cases of gastrointestinal bleeding of obscure origin, duodenal diverticulum should be considered as a possible source of bleeding, even when endoscopy discloses no apparent bleeding. 相似文献
70.
Akitoshi Yamada Yoshitaka Takeda Satoru Hayashi Kazuta Shimizu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(9):456-458
We experienced a case of familial spontaneous pneumothorax in three generations. Six of 13 family members had episodes of
spontaneous pneumothorax. It is well established that there are some diseases associated with human leukocyte antigen (HLA).
We performed HLA phenotyping for HLA of A, B and C. In our study, we detected the HLA haplotype A2, B61 in three of 4 who
had episodes of spontaneous pneumothorax. The HLA haplotype A2, B70 were also detected in three of 4 who had episodes. This
suggests that familial spontaneous pneumothorax might have hereditary factors. 相似文献