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101.
Comparative study is performed between echocardiographic measurements (TM), exercise test blood pressure profile (ETP) and ambulatory blood pressure load (BPL) in 26 borderline hypertensive subjects (19 males, 7 females). An abnormal ETP is found for 15 subjects (57 p. 100), an abnormal BPL for 10 subjects (38 p. 100). The diastolic interventricular septum thickness (IVS) and the diastolic posterior wall thickness (PWT) are abnormal (greater than 11 mm) for 6 and 3 subjects. Patient with pathologic ETP or/and BPL have greater IVS and PWT than other subjects (p less than 0,001). A good correlation is found between individual activity systolic blood pressure or 24 hours systolic blood pressure means values and PWT, IVS or left ventricular mass. These 3 examinations lead to a better assessment of cardiovascular strain and allow a better diagnosis and therapeutic approach in borderline hypertensive patients.  相似文献   
102.
The aim of the present study was to evaluate the effect of gamma-irradiation on soluble gastric mucus. Six conscious chair-adapted rhesus monkeys were studied once before and twice after exposure to ionizing irradiation (800 rads). Using a marker (99mTc-DTPA) dilution technique, acidic glycoprotein (AG), neutral glycoprotein (NG), ion, and fluid output were determined during a basal period and after the administration of an 80-ml water load. Irradiation significantly increased the outputs of both AG and NG during the basal period. After the water load, NG output remained elevated but irradiation abolished postload AG output thus inhibiting the normal rise in AG output stimulated by the load. Two days after irradiation NG output had returned to control levels whereas AG output was still suppressed. Sodium and potassium ion outputs were unaltered by irradiation. Chloride and fluid outputs were significantly inhibited on the day of irradiation but had returned to control levels within 3 days. These results indicate that irradiation produces significant changes in both the quantity and nature of the soluble mucus glycoproteins secreted into the gastric juice. It is suggested that these changes may compromise the protective ability of gastric mucus.  相似文献   
103.
A transgenic (Tg) mouse expressing human IL-15 was generated to define the role of IL-15 in the normal immune response. Overexpression of IL-15 resulted in an increase of NK, CD44(hi)CD8 memory T cells, and gammadelta T cells. Additionally, we observed the emergence of a novel type of NK-T cells with CD8alphaalpha' expression. Due to the expansion and activation of NK cells, the IL-15Tg mouse showed enhanced innate immunity. In adaptive T cell immunity, the roles of IL-15 contrasted with those of IL-2. IL-15 inhibited IL-2-induced T cell death, which plays a role in the maintenance of peripheral self-tolerance. IL-15 thus seems to contribute to enhanced immune memory by selectively propagating memory T cells and by blocking T cell death mediated by IL-2.  相似文献   
104.
To define the independent variables predictive of early versus late mortality after acute myocardial infarction (AMI), 420 consecutive patients were studied and divided into 3 groups: the 45 patients who died within the initial 3 months (group 1), the 45 patients who died greater than 3 months and less than or equal to 3 years after AMI (group 2) and the 330 greater than 3-year survivors (group 3). The stepwise logistic discrimination method was applied to clinical and laboratory variables recorded during hospitalization to distinguish among the 3 groups. Six independent variables were found to be predictive of early mortality: left ventricular function score (chi-square 26.2; p less than 0.00001), ventricular fibrillation (chi-square 9.3; p = 0.002), bundle branch block (chi-square 9.0; p = 0.003), history of previous AMI (chi-square 8.7; p = 0.003), age (chi-square 5.8; p = 0.02) and atrioventricular block (chi-square 3.8; p = 0.05). Three independent variables were found predictive of late mortality: age (chi-square 13.8; p = 0.0002), anterior location of the AMI (chi-square 4.0; p = 0.04) and a low peak creatine kinase-MB level (chi-square 3.8; p = 0.05). Only 2 variables were able to distinguish between early and late nonsurvivors: peak creatine kinase-MB level (chi-square 8.7; p = 0.003) and ventricular fibrillation (chi-square 4.6; p = 0.03). Thus, the sets of independent risk factors for early and late mortality after AMI are substantially different--suggesting that differing mechanisms are responsible for outcome.  相似文献   
105.
OBJECTIVE: Vascular impairment, a main feature of the pathogenesis of systemic sclerosis (SSc), involves both the macro- and the microvasculature. We compared and correlated simultaneously measured skin microvascular and brachial artery macrovascular post-occlusive hyperemia in 3 groups: patients with SSc, patients with primary Raynaud's phenomenon (RP), and healthy volunteers. METHODS: Thirty-three healthy volunteers, 36 patients with primary RP, and 42 patients with SSc were enrolled. For each subject, brachial artery flow-mediated dilation (FMD) and cutaneous post-occlusive reactive hyperemia (PORH) were simultaneously recorded after 5-minute occlusion of the brachial artery. Local thermal hyperemia, nitroglycerin-mediated dilation (NMD), intima-media thickness (IMT), and pulse wave velocity (PWV) were also assessed. RESULTS: Digital cutaneous peak PORH was altered in patients with primary RP and SSc compared to healthy controls, whereas FMD was not significantly different among all groups. We observed a correlation between digital peak cutaneous vascular conductance and brachial FMD in healthy controls (r = 0.49; p = 0.004), but not in patients with primary RP or SSc. Thermal hyperemia was altered only in patients with SSc. Brachial NMD, IMT, and PWV were not different among all groups. CONCLUSION: We observed a loss of the correlation between brachial FMD and digital cutaneous PORH in patients with SSc and primary RP. Microvascular function is impaired in SSc, whereas brachial artery endothelial function is normal.  相似文献   
106.
Short-chain fatty acids (SCFAs) alter ileal and colonic motility, but their effects on duodenojejunal motility are unknown. Simultaneous jejunal manometric recordings and hydrogen breath tests after lactulose were performed in eight healthy subjects during continuous duodenal infusion of either saline or SCFAs. These experiments were conducted in the fasting state and postprandially. The effects of various boluses of SCFAs on duodenojejunal motility were also determined in six subjects. During the fasting period, the number and characteristics of migrating motor complex, prolonged propagated contractions, discrete clustered contractions, motility indes, and orocecal transit time were similar during saline and SCFAs. Similarly, the motility index and the duration of the postprandial period were not different between SCFAs and saline after the meal. The motility index was significantly increased after each of the 100-ml boluses (saline or SCFAs), but was not altered after the 12.5-ml boluses, suggesting a volume-related effect. Thus, SCFAs do not seem to affect proximal small bowel motility in healthy humans.This work was supported in part by a research grant from Institut National de la Santé et de la Recherche Médicale (INSERM) (CRE 887009), and by Smith Kline and French (Paris, France).  相似文献   
107.
Among 1013 consecutive patients with acute myocardial infarction (AMI), 104 (10%) developed complete bundle-branch block (BBB). The clinical characteristics and the short- and long-term prognosis were similar in the 53 patients with right and the 51 patients with left BBB. Compared to the 909 patients without this conduction disturbance, these 104 patients were older (64 +/- 9 vs. 58 +/- 10 years, p less than 0.001), more frequently women (26 vs. 17%, p less than 0.05), had a larger infarct (peak CK 1672 +/- 1124 vs. 1356 +/- 1089 IU/l, p less than 0.001), more frequently anterior (60 vs. 37%, p less than 0.001). They had a higher incidence of Killip class greater than 1 (63 vs. 38%, p less than 0.001), pericarditis (40 vs. 23%, p less than 0.001), atrial fibrillation or flutter (22 vs. 12%, p less than 0.01), ventricular fibrillation (15 vs. 9%, p less than 0.05), and atrioventricular block (23 vs. 11%, p less than 0.001). Both hospital mortality (32 vs 10%, p less than 0.001) and 3-year posthospital mortality (37 vs. 18%, p less than 0.001) were much higher among patients with complete BBB. Transient BBB had the same deleterious prognosis as BBB persistent at discharge (mortality 33 vs. 39%, NS). The prognostic importance of BBB was more prominent during the first 6 months after infarction (mortality between 6 and 36 months: 18% with BBB vs. 11% without BBB, NS).  相似文献   
108.
A precise targeting of the SV40 T early region expression in the liver of transgenic mice was obtained using 700 bp of the antithrombin III regulatory sequences to control oncogene expression. In the strain expressing the highest level of large T antigen (Tag), the incidence of hepatocarcinoma was 100%. The evolution was reproducible and characterized by a marked cytolysis occurring as early as 4 weeks, when no morphological and histological modifications were visible, a preneoplastic state marked by a progression from hyperplasia to proliferative nodules composed of highly differentiated cells exhibiting a high Tag expression, which elicited tumor formation in nude mice and could proliferate in vitro, and hepatocellular carcinoma associated, in 10% of the cases, with lung metastasis. These transgenic mice constituted a useful model for therapeutic assays and fundamental studies on carcinogenesis.  相似文献   
109.
OBJECTIVE: Prediction of the clinical course of Crohn's disease (CD) is difficult in the long term. Our aim was to determine whether the presence of severe endoscopic lesions (SELs) may predict a higher risk of colectomy and penetrating complications. METHODS: All patients at our institution with active ileocoIonic CD who had colonoscopies between 1990 and 1996 were included in the study. SELs were defined as extensive and deep ulcerations covering more than 10% of the mucosal area of at least one segment of the colon. RESULTS: Among the 102 patients included, 53 had SELs at index colonoscopy. During the follow-up (median = 52 months), 37 patients underwent colonic resection. Probabilities of colectomy at 1, 3, and 8 yr were 20%, 26%, and 42%. Risk of colectomy was independently affected by the presence of SELs at index colonoscopy (relative risk [RR] = 5.43, 95% CI = 2.64-11.18), a Crohn's Disease Activity Index level greater than 288 (RR = 2.21, 95% CI = 1.09-4.47), and the absence of immunosuppressive therapy during the follow-up (RR = 2.44, 95% CI = 1.20-5.00). Probabilities of colectomy were, respectively, 31% and 6% at 1 yr, 42% and 8% at 3 yr, and 62% and 18% at 8 yr in patients with and without SELs. We performed a second analysis excluding the 14 patients operated on within the 3 months after the index colonoscopy: presence of SELs remained the only significant factor predictive of colectomy (RR = 6.72, 95% CI = 2.26-20.03). All six patients with penetrating complications during the follow-up had SELs at index colonoscopy. CONCLUSIONS: Patients with CD exhibiting deep and extensive ulcerations at colonoscopy have a more aggressive clinical course with an increased rate of penetrating complications and surgery.  相似文献   
110.
The tetradecapeptide, somatostatin (SRIF), is a potent inhibitor on pituitary hormone release, by a direct effect. The immunocytological method was used with the aim of localizing SRIF at the cellular and subcellular levels. Rat pituitaries were fixed and frozen. Ultrathin sections obtained by cryoultramicrotomy, were incubated with anti-SRIF serum. The antigen-antibody reaction was detected by 4-chloro-1-naphthol. SRIF immunoreactivity was observed in somatotrophs, thyreotrophs and prolactin cells, but not in corticotrophs or gonadotrophs. Im immunoreactive cells, SRIF was found in the cytoplasmic matrix, in the secretory granules and in the nucleus distributed primarily in the euchromatin, in the vicinity of the heterochromatin regions. SRIF immunoreactivity was also observed at the plasma membrane. No immunoreactivity was observed when nonimmune serum or anti-SRIF serum incubated with SRIF was used. No modification was observed when anti-SRIF serum incubated with gonadoliberin, thyroliberin or vasopressin was used. These data (1) provide immunocytological evidence for the presence of somatostatin in pituitary gland, and (2) indicate the presence of SRIF peptide in the somatotrophs, thyreotrophs and prolactin cells.  相似文献   
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