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21.
Contribution of passive transport mechanisms to the intestinal absorption of beta-lactam antibiotics
M Sugawara H Saitoh K Iseki K Miyazaki T Arita 《The Journal of pharmacy and pharmacology》1990,42(5):314-318
The transport characteristics of aminopenicillins (ampicillin and amoxicillin), aminocephalosporins (cephalexin, cephradine and cefadroxil) and cefazolin have been compared with those of an actively transported substance (D-glucose) and a passively transported substance (L-glucose). Although the initial uptake of the aminocephalosporins was stimulated in the presence of an inward H+ gradient, there was no overshoot in the uptake of any of the drugs tested, even in the presence of an H+ gradient. Also, the time course and the degree of uptake of these drugs were similar to those of L-glucose, especially in the absence of an H+ gradient. These results suggest that the beta-lactam antibiotics tested, like L-glucose, pass through the rat intestinal brush border membrane mainly by passive diffusion. However, the differences in absorption between these drugs, like the differences in their disappearance from a proximal loop of rat intestine, cannot be explained by a simple permeation process alone. 相似文献
22.
Yutaka Yonemura Masataka Segawa Hisashi Matsumoto Kouichirou Tsugawa Itasu Ninomiya Luis Fonseca Takashi Fujimura Kazuo Sugiyama Kouichi Miwa Itsuo Miyazaki 《Surgery today》1994,24(6):488-493
Because gastric cancers located in the upper third of the stomach are difficult to detect at an early stage, the surgical results remain poor. We performed R4 gastrectomy as a radical procedure for 25 patients, involving complete resection of the latero-aortic and interaorticovenous lymph modes above and below the left renal vein, in combination with the ordinary R2 or R3 gastrectomy (the R4 group). These patients were compared with 156 others who underwent R2 gastrectomy alone (the R2 group). There were no significant differences in operation time, blood loss, or the incidence of complications between the two groups; however, when the survival rates of the patients with tumors invading beyond the subserosa were compared, the 5-year survival rate was found to be significantly higher in the R4 group than in the R2 group. Furthermore, in patients with para-aortic nodal involvement, a significant survival advantage was observed in the R4 group, as compared with the R2 group. These results suggest that the R4 gastrectomy is a rational approach for patients with advanced gastric cancer located in the upper third of the stomach. 相似文献
23.
Japan Pancreatoduodenectomy Study Group Ryo Hosotani Masafumi Kogire Tadahiro Takada Hiroyuki Kato Takahiko Funabiki Masumasa Horisawa Takeshi Morimoto Takukazu Nagakawa Toshimichi Nakayama Itsuo Miyazaki Masayuki Imamura 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):295-303
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity
the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy
(JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery,
and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning
tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion;
the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection
was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic
resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant
tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative
resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic
factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection
with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor.
This study was carried out as a group project. The authors' institutions are as follows 相似文献
24.
Y Imanishi M Kishiro O Miyazaki T Toyokawa K Kuroki H Haji T Ishikawa 《Clinical nuclear medicine》1992,17(2):114-118
Metastatic calcifications according to histopathologic and scintigraphic findings have been well-defined. The authors report a postoperative case of hyperparathyroidism with multiple metastatic calcifications in the lung, kidney, stomach, heart, and vessels that were primarily detected by bone scintigraphy and demonstrated by CT. Tc-99m MDP bone scintigraphy showed a markedly increased accumulation of radioactivity diffusely throughout the lung, left ventricular wall, both kidneys, and the gastric cardia and body. In the lung, plain films showed almost normal lung. CT, however, demonstrated patchy, slightly increased densities in the lung bilaterally. Cardiac CT indicated a considerably increased density of the ventricular myocardium and remarkable calcification in or near the atrioventricular septum or annulus fibrosus. Upper abdominal CT demonstrated increased densities diffusely throughout the gastric mucosa and renal cortex. Only vascular calcifications were depicted by plain films. Using both bone scintigraphy and CT provides accurate information about each lesion and each tissue, allowing precise diagnosis of even a questionable lesion in the early stage of metastatic calcification. Early diagnosis and early therapy offer the best chance for cure or palliative therapy. 相似文献
25.
26.
In 2002, psychiatrically disabled athletes joined an historic first open game of volleyball at the national sports games for the disabled. Compared to the competitive sports and Paralympic Games that physically and intellectually disabled athletes have participated in, activities for the psychiatrically disabled have not been well-organized. In this paper, we examine a number of problems that have arisen when the psychiatrically disabled joined competitive sports games. We identify two major characteristics of the psychiatrically disabled of particular relevance when organizing competitive sports activities. First, all psychiatrically disabled athletes need treatment of their individual diseases. For example, psychiatric symptoms fluctuate markedly over time, unlike physical or intellectual disabilities, whose symptoms are much more stable. Exacerbations of psychiatric illness are also likely to occur due to the stresses of competitiveness. Second, psychiatric disabilities are manifestations of disorders in the central nervous system, which makes the classification of psychiatric disabilities less straightforward than classification of the physically disabled. These two characteristics require special attention when organizing competitive athletic challenges that include the psychiatrically disabled. However, promoting sports activities that include the psychiatrically disabled would be expected to reduce the prejudice toward and subsequent social disadvantages experienced by psychiatric patients. Thus, with careful planning to successfully integrate psychiatrically disabled athletes, we expect increased promotion of such sports activities in the future. 相似文献
27.
Late Effects of Childhood Acute Leukemia and Its Treatment 总被引:1,自引:0,他引:1
Masao Yamamoto M.D. Yoshitaka Fukunaga M.D. Ichiroh Tsukimoto M.D. Fumio Bessho M.D. Jun-ichi Akatsuka M.D. Ryohta Hosoya M.D. Shinpei Nakazawa M.D. Minoru Sakurai M.D. Kazuhiro Ueda M.D. Sumio Miyazaki M.D. Masaru Yokoyama M.D. Hideo Mugishima M.D. Kohzoh Nishimura M.D. 《Pediatrics international》1991,33(4):573-588
Late effects of childhood acute leukemia and its treatment were studied in 766 patients (684 ALL, 73 ANLL, and 9 others) in Japan who had remained in remission for more than 1 year after their first complete remission. Delayed adverse sequelae involve a wide variety of organs and their functions. Short stature was present in 2.61%, obesity in 3.79%, abnormalities of growth hormone secretion in 1.5%, delayed secondary sex characteristics in 1.5% of males and 0.6% of females, motor disturbances in 1.17%, sensory disturbances in 0.91%, intellectual and learning disabilities in 2.48%, abnormal findings in routine neurologic examinations in 1.31%, EEG abnormalities in 4.30%, brain CT abnormalities in 5.09% and cardiac dysfunction in 1.07%. Various other disorders were seen in 20 patients. Many of these delayed adverse sequelae are caused by or related to central nervous system prophylaxis and systemic combination chemotherapy. The results suggest that it is needed to improve therapeutic methods through the stratification of patients by risk factors and detailed analysis of prognostic factors. Moreover it is important to render medical and psychosocial support to long-term survivors of childhood leukemia through interactions between the patient, parents and medical staff. 相似文献
28.
Fusiform posterior cerebral artery aneurysm treated with excision and end-to-end anastomosis. Case report 总被引:2,自引:0,他引:2
A case of a ruptured fusiform aneurysm of the posterior cerebral artery is reported. The aneurysm was excised and end-to-end anastomosis was carried out between the two ends of the posterior cerebral artery. There is no previous report of a posterior cerebral artery aneurysm treated with this technique. The pertinent literature is reviewed and the significance of this technique in the treatment of unclippable cerebral aneurysms is discussed. 相似文献
29.
30.
Protection against autonomic denervation following acute myocardial infarction by preconditioning ischemia 总被引:3,自引:0,他引:3
To examine the effects of ischemic preconditioning on efferent autonomic responses following acute transmural myocardial ischemia/infarction (MI), the time course and extent of efferent sympathetic and vagal denervation were compared between control dogs that received a one-stage sustained coronary occlusion and preconditioned dogs that received four 5-minute coronary occlusions separated by 5 minutes of reperfusion before sustained occlusion. Effective refractory periods (ERP) basal and apical to MI were determined in the baseline state and during neural stimulation before and after preconditioning occlusions and 20, 60, 120, and 180 minutes after sustained occlusion by ligature ligation of diagonal branches of the left anterior descending coronary artery. In 10 control dogs with transmural MI, ERP shortening induced by bilateral ansae subclaviae stimulation (4-msec pulses, 2-4 Hz and 2-4 mA) was unchanged at basal sites but was attenuated at apical sites. Four of 40 apical test sites exhibited efferent sympathetic denervation (less than or equal to 2 msec shortening) 20 minutes after sustained occlusion. Thirteen of 40 apical sites became denervated during a 3-hour period. In 10 preconditioned dogs, ERP shortening at apical sites was unchanged after preconditioning occlusions and during the first 60 minutes of sustained ischemia but was attenuated at 120 minutes. Three of 40 apical test sites became denervated during a 3-hour period. The cumulative percentage of denervated apical test sites was significantly less in the preconditioned group compared with the control group (p = 0.006) despite a comparable degree of subepicardial involvement in the MI (8.2 +/- 1.0% vs. 8.4 +/- 1.4%, the ratio to the left ventricular circumference, mean +/- SEM). In 11 control dogs tested for efferent vagal response after MI, ERP prolongation induced by bilateral vagal stimulation (4-msec pulses, 20 Hz with current strength 0.05 mA greater than that required to produce asystole) was unchanged at basal sites, but was attenuated at apical sites, and five of 44 test sites exhibited denervation (less than or equal to 1 msec prolongation) 20 minutes after sustained coronary occlusion. Fourteen of 40 apical sites became denervated during a 3-hour period. In 10 preconditioned dogs, vagally induced ERP prolongation was unchanged both at basal and apical sites, and none of 36 apical test sites exhibited denervation after preconditioning and during a 3-hour period of sustained coronary occlusion (p less than 0.001 vs. control group) despite a comparable degree of subendocardial involvement in the MI (11.8 +/- 0.8% vs. 11.9 +/- 1.3%).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献