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排序方式: 共有458条查询结果,搜索用时 171 毫秒
91.
Paolo Taurisano Giuseppe Blasi Raffaella Romano Fabio Sambataro Leonardo Fazio Barbara Gelao Gianluca Ursini Luciana Lo Bianco Annabella Di Giorgio Francesca Ferrante Apostolos Papazacharias Annamaria Porcelli Lorenzo Sinibaldi Teresa Popolizio Alessandro Bertolino 《Social cognitive and affective neuroscience》2013,8(8):855-862
Background: Maternal care (MC) and dopamine modulate brain activity during emotion processing in inferior frontal gyrus (IFG), striatum and amygdala. Reuptake of dopamine from the synapse is performed by the dopamine transporter (DAT), whose abundance is predicted by variation in its gene (DAT 3′VNTR; 10 > 9-repeat alleles). Here, we investigated the interaction between perceived MC and DAT 3′VNTR genotype on brain activity during processing of aversive facial emotional stimuli.Methods: Sixty-one healthy subjects were genotyped for DAT 3′VNTR and categorized in low and high MC individuals. They underwent functional magnetic resonance imaging while performing a task requiring gender discrimination of facial stimuli with angry, fearful or neutral expressions.Results: An interaction between facial expression, DAT genotype and MC was found in left IFG, such that low MC and homozygosity for the 10-repeat allele are associated with greater activity during processing of fearful faces. This greater activity was also inversely correlated with a measure of emotion control as scored with the Big Five Questionnaire. Moreover, MC and DAT genotype described a double dissociation on functional connectivity between IFG and amygdala.Conclusion: These findings suggest that perceived early parental bonding may interact with DAT 3′VNTR genotype in modulating brain activity during emotionally relevant inputs. 相似文献
92.
A cross‐cultural investigation of attachment style,catastrophizing, negative pain beliefs,and symptom severity in irritable bowel syndrome 下载免费PDF全文
93.
The present investigation studied the effects of hydrogen ion concentration on pulmonary vascular reactivity to the biogenic amines in vitro. Pulmonary arterial segments from cats were dissected free of surrounding tissue and endothelium and isometrically suspended in tissue baths. Cumulative dose-response curves were constructed to norepinephrine, histamine, serotonin, and potassium chloride, and the protocol was designed such that only one agent and hydrogen ion concentration was studied in each vessel segment. Alkalosis ([H+] less than or equal to 28 nmol/l) produced enhanced maximum responses to all of the agents used in this study. Acidosis [( H+] greater than or equal to 52 nmol/l), in contrast, was without effect on the maximum responses to histamine, serotonin, and potassium chloride, but did produce increased maximum responses to norepinephrine. No alterations in the ED50 of the dose-response curves were observed for any of the agents tested. In general, increases in sloped of the dose response curves were correlated with hydrogen ion concentrations that demonstrated increased maximum responses, suggesting that the present observations may have resulted from hydrogen ion-induced changes in amine receptor efficacy. The present data demonstrate that (1) as in the in vivo model, pulmonary vascular amine receptor activity is related to the hydrogen ion concentration; (2) there are two hydrogen ion concentration ranges where adrenergic receptor activity was observed to be enhanced; (3) the effects of acidosis where specific for the adrenergic receptor system, since the reactivity to only norepinephrine was significantly altered by acidosis; and (4) the effects of alkalosis may have resulted from increased overall contractility of the pulmonary vascular smooth muscle cells, since the force developed to all the agents tested was enhanced by alkalosis. 相似文献
94.
B. Porcelli L. Terzuoli B. Frosi C. Felici L. Barabesi S. Naddeo S. Meini D. Pieragalli I. Baldi G. de Donato E. Marinello M Giubbolini C. Setacci 《The International journal of angiology》2005,14(1):7-10
Although involvement of free radicals in atherosclerosis is well researched, few parameters indicative of the body’s antioxidant
capacity have been analyzed in this disease. We analyzed total antioxidant capacity and a series of antioxidants in the plasma
of subjects with atherosclerosis. The information obtained could help to understand the role of antioxidants in this disorder
and to evaluate their potential use in the prevention of atherosclerosis. Fifty-five controls (24 males, 31 females) and 96
subjects with atherosclerosis of the carotid (53 subjects: 34 males, 19 females), the lower limbs (15 subjects: 12 males,
3 females), and both areas (28 subjects: 18 males, 10 females) were analyzed. All subjects were examined by echo-color Doppler.
For carotid atherosclerosis, symptoms and neurologic status were evaluated. For lower-limb involvement, symptoms were evaluated
according to Leriche–Fontaine. The following parameters were recorded: body mass index, smoking, hyperlipidemia, hypertension,
diabetes, and drugs taken. Plasma samples were analyzed for total antioxidant capacity, hypoxanthine, xanthine, uric acid,
vitamin A, vitamin E, and coenzyme Q10. Vitamin A was higher (p < 0.01) in atherosclerosis patients than in controls, as was uric acid (p < 0.05). No correlation was found between the parameters examined in the present study. Although a wider series of parameters
than previously examined in the literature was evaluated in this study, the information obtained was not clear, confirming
that this type of study is complicated by a series of factors that influence the antioxidant defense system. 相似文献
95.
In the preceding paper it was shown that transient neonatal hypothyroidism induced by treatment of rats from birth to day 25 with the goitrogen 6-propyl-2-thiouracil (PTU) is associated with increases in testis wt and DNA content of up to 80% during adulthood. The testis changes were accompanied by similar, though less marked, increases in the wt and DNA content of epididymis and accessory organs. The purpose of this study was to assess sperm production in these enlarged testes and measure changes in sperm reserves in the epididymis. Testes and epididymides were obtained from control rats or rats given PTU from birth to day 25 (designated "treated") at 90, 135, 160, and 180 days of age. Daily sperm production (DSP), efficiency of sperm production (DSP/g testis), and epididymal sperm reserves were measured in all animals. Compared to controls, DSP of the treated rats was increased by 83%, 86%, 136%, and 132% at 90, 135, 160, and 180 days, respectively. Thus, in the treated rats, DSP, like testis wt, plateaued at day 160. In addition, efficiency of sperm production was increased by 15%-30% at all ages in treated animals. Epididymal sperm reserves were also increased in treated rats at all ages, but the correlation between DSP and epididymal sperm reserves was weak. Sperm motility and concentration in caudal epididymal fluid of adult males treated from birth to day 25 with PTU were normal. These males were fertile and sired litters in which pup wt and pup number were normal. These results indicate that neonatal hypothyroidism in rats is associated not only with increased testis size but also with increased efficiency of sperm production, resulting in increases in DSP of up to 140% in these animals during adulthood. Maximal sperm production is reached at 160 days of age in treated rats (compared to 100 days in controls), coinciding with the attainment of final testicular size. This system represents the first experimental model in which such large increases in sperm production can be produced. The neonatal PTU treatment does not appear to impair fertility or alter sperm characteristics when these animals become adults and may be a useful system with which to study factors which normally regulate sperm production. 相似文献
96.
Marzano LA Tauchmanova L Marzano E Arienzo R Guarino R Ciancia G Porcelli A Lombardi G Rossi R 《Journal of endocrinological investigation》2007,30(1):52-58
This is a case report on a young woman with a large idiopathic unilateral adrenal hematoma (AH). Only few cases of AH which were not associated with any trauma, previous surgery, coagulative or any other systemic disorders have been described. The mass was discovered by abdominal ultrasound which was performed for a recent flank pain. Magnetic resonance imaging (MRI) confirmed the presence of a 13-cm sized lesion in the right hemi-abdomen; T1 and T2 weighed imaging was compatible with subacute-to-chronic adrenal hematoma. The lesion dislocated the liver and right kidney. Positron emission tomography (PET) did not show any significant radiotracer uptake by the mass. Serum cortisol, aldosterone, renin activity and DHEA-S were normal. Urinary catecholamines and free cortisol excretion were within the normal range too. The lesion was removed by transabdominal laparoscopic adrenalectomy without any complication. The histological exam confirmed a large subacute- to-chronic organized AH. In conclusion, in the absence of known risk factors, differential diagnosis of a large AH may not be easy. The possibility of an underlying pheochromocytoma, malignant adrenal or metastatic tumor must always be considered. In our patient, computed tomography (CT) scan and MRI suggested the presence of a large subacute-to-chronic AH, and PET excluded metabolic activity of the mass. Laparoscopic adrenalectomy can be the surgical treatment of choice in organized symptomatic AH. The correct diagnosis, early recognition and treatment of complications including adrenal insufficiency may decrease patient morbidity and mortality. 相似文献
97.
De Marinis L Bianchi A Mancini A Gentilella R Perrelli M Giampietro A Porcelli T Tilaro L Fusco A Valle D Tacchino RM 《The Journal of clinical endocrinology and metabolism》2004,89(1):174-180
Obesity is characterized by increased leptin levels and insulin resistance, whereas blunted GH secretion is paired with normal, low, or high plasma IGF-I levels. To investigate body composition in human obesity and the interactions among the GH-IGF-I axis, leptin, and insulin resistance [measured with the homeostasis model assessment (HOMA) score], we studied 15 obese females, aged 23-54 yr (mean age, 42.7 +/- 2.6), with a body mass index (BMI) of 44.02 +/- 1.45 kg/m(2), who underwent treatment by biliopancreatic diversion (BPD), before and after surgery (16-24 months; BMI, 28.29 +/- 0.89 kg/m(2)). Our controls were 15 normal females, aged 28-54 yr (mean age, 40.8 +/- 2.3 yr), with a BMI of 27.52 +/- 0.53 kg/m(2). Insulin and leptin levels and HOMA scores were higher pre-BPD than in the controls. The GH response to GHRH was blunted, with a GH peak and GH area under the curve (AUC) significantly lower than those in controls. IGF-I and IGF-binding protein-3 (IGFBP-3) were also lower than control values. After surgery, BMI, fat mass, lean body mass, HOMA, insulin, and leptin significantly decreased. Furthermore, the GH response to GHRH severely increased; IGF-I and IGFBP-3 levels did not significantly vary. Considering all subjects, correlation analysis showed a strong positive correlation between insulin and leptin, and a negative correlation between insulin and GH peak and between insulin and GH AUC. Regression analysis performed grouping pre- and post-BPD indicated that leptin and GH peak or AUC could best be predicted from insulin levels. The surgical treatment of severe obesity after stabilization of body weight decreases BMI and fat mass while preserving normal lean body mass as well as positively influencing insulin sensitivity and thus aiding the normalization of leptin levels. The insulin reduction may be mainly involved in the increase in the GH response to GHRH through various possible central and peripheral mechanisms while decreasing the peripheral sensitivity to GH itself, as shown by the stable nature of the IGF-I and IGFBP-3 values. Our findings suggest that the changes in insulin levels are the starting point for changes in both leptin levels and the somatotrope axis after BPD. 相似文献
98.
Stefano Porcelli Oriana Bianchini Giovanni De Girolamo Eugenio Aguglia Luciana Crea 《International journal of psychiatry in clinical practice》2016,20(2):54-69
Objective: Relapses represent one of the main problems of schizophrenia management. This article reviews the clinical factors associated with schizophrenia relapse. Methods: A research of the last 22 years of literature data was performed. Two-hundred nineteen studies have been included. Results: Three main groups of factors are related to relapse: factors associated with pharmacological treatment, add-on psychotherapeutic treatments and general risk factors. Overall, the absence of a maintenance therapy and treatment with first generation antipsychotics has been associated with higher risk of relapse. Further, psychotherapy add-on, particularly with cognitive behaviour therapy and psycho-education for both patients and relatives, has shown a good efficacy for reducing the relapse rate. Among general risk factors, some could be modified, such as the duration of untreated psychosis or the substance misuse, while others could not be modified as male gender or low pre-morbid level of functioning. Conclusion: Several classes of risk factors have been proved to be relevant in the risk of relapse. Thus, a careful assessment of the risk factors here identified should be performed in daily clinical practice in order to individualise the relapse risk for each patient and to provide a targeted treatment in high-risk subjects. 相似文献
99.
E S Hiatt P G Brunetta G R Seiler S A Barney W D Selles K H Wooledge J C King 《Endocrinology》1992,130(2):1030-1043
The hypothesis that the basal forebrain population of LHRH perikarya is composed of heterogeneous subgroups was examined in this study. We used three-dimensional computerized reconstruction to examine populations of LHRH-immunopositive neurons detected in noncolchicine treated cycling female rats. Perikarya were detected with two antisera capable of detecting LHRH decapeptide within larger mol wt species, i.e. Millar's (RM) 1076 and Arimura's (AA) 419. No immunopositive perikarya were detected with antiserum AA 422, which requires the fully processed decapeptide for binding. A more broadly distributed population of LHRH neurons was detected in females killed on proestrus than in females killed on estrus or the other days of the cycle. These relationships were observed with both antisera, RM 1076 and AA 419. Subgroups of cells were clearly defined when the population of LHRH neurons detected on proestrus was simultaneously displayed with the population detected on estrus. Strikingly similar subgroups were revealed by simultaneous displays of populations of LHRH neurons detected by the antisera RM 1076 and AA 419 in proestrous females. This study revealed a three-dimensional onion skin-like laminar organization of LHRH subgroups expanding from the ventricle outward laterally and from the diagonal band of Broca to the hypothalamus caudally. We propose that these subgroups vary in their metabolic activity of biosynthesis, processing, transport, or release of LHRH in relation to the proestrous preovulatory release of LH. 相似文献
100.
No abstract available. 相似文献