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Cerebrospinal fluid and plasma concentrations of oxytocin and vasopressin during parturition and vaginocervical stimulation in the sheep 总被引:1,自引:0,他引:1
Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli. 相似文献
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Outcome Following Bariatric Surgery in Super versus Morbidly Obese Patients: Does Weight Matter? 总被引:4,自引:2,他引:2
Mark Bloomston MD Emmanuel E Zervos MD Mario A Camps MD Sarah E Goode RN Alexander S Rosemurgy MD 《Obesity surgery》1997,7(5):414-419
Background: Numerous investigators have attempted to identify prognostic indicators for successful outcome following bariatric
surgery. The purpose of this study was to determine whether degree of obesity affects outcome in super obese [>225% ideal
body weight (IBW)] versus morbidly obese patients (160-225% IBW) undergoing gastric restrictive/bypass procedures. Methods:
Since 1984, 157 patients underwent either gastric bypass or vertical banded gastroplasty. Super obese (78) and morbidly obese
(79) patients were followed prospectively, documenting outcome and complications. Results: Super obese patients reached maximum
weight loss 3 years following bariatric surgery, exhibiting a decrease in body mass index (BMI) from 61 to 39 kg/m2 and an average loss of 42% excess body weight (EBW). Morbidly obese patients had a decrease in BMI from 44 to 31 kg/m2 and carried 39% EBW at 1 year. After their respective nadirs, each group began to regain the lost weight with the super obese
exhibiting a current BMI of 45 kg/m2 (61% EBW) versus 34 kg/m2 (52% EBW) in the morbidly obese at 72 months cumulative follow-up. Currently, loss of 50% or more of EBW occurred in 53%
of super obese patients versus 72% of morbidly obese (P < 0.01). Twenty-six percent of super obese patients returned to within 50% of ideal body weight (IBW) while 71% of morbidly
obese were able to reach this goal (P < 0.01). Co-morbidities and complications related to surgery were similar in each group. Conclusions: Super obese patients
have a greater absolute weight loss after bariatric surgery than do morbidly obese patients. Using commonly utilized measures
of success based on weight, morbidly obese patients tend to have better outcomes following bariatric surgery. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
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The monitoring of micronutrients and the relationship between dietary intake and micronutrient status prior to and after surgery in patients with histologically proven gastrointestinal adenocarcinoma, both weight-stable and weight-losing (> 7.5% of their pre-illness weight) has been studied and the results compared to controls. Plasma vitamin C and red blood cell thiamine levels were significantly lower in weight-losing cancer patients when compared to their weight-stable counterparts (P < 0.05 and P < 0.02 respectively). Weight-losing patients had a lower vitamin C (P < 0.05) and thiamine (P < 0.002) intake, and a higher elevation in plasma C-reactive protein and a lower prealbumin level (P < 0.02), when compared to both weight-stable cancer patients and controls. Plasma vitamin C, prealbumin and C-reactive protein levels remained unchanged after curative resections of the tumours compared to a preoperative value, and there was a highly significant correlation between plasma vitamin C and dietary intake of vitamin C. This study suggests that the lower vitamin C and thiamine status in weight-losing gastrointestinal cancer patients prior to surgery is due to a lower micronutrient intake and an acute phase response to their illness. Dietary intake of vitamin C appears to be the major factor in determining plasma vitamin C concentration following curative surgical resection. 相似文献