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821.
Pituitary - Non-syndromic pituitary gigantism (PG) is a very rare disease. Aryl hydrocarbon receptor-interacting protein (AIP) and G protein-coupled receptor 101 (GPR101) genetic abnormalities...  相似文献   
822.
The nonalcoholic fatty liver disease(NAFLD) is the hepatic manifestation of the metabolic syndrome. NAFLD encompasses a wide histological spectrum ranging from benign simple steatosis to non-alcoholic steatohepatitis(NASH). Sustained inflammation in the liver is critical in this process. Hepatic macrophages, including liver resident macropaghes(Kupffer cells), monocytes infiltrating the injured liver, as well as specific lymphocytes subsets play a pivotal role in the initiation and perpetuation of the inflammatory response, with a major deleterious impact on the progression of fatty liver to fibrosis. During the last years, Th17 cells have been involved in the development of inflammation not only in liver but also in other organs, such as adipose tissue or lung. Differentiation of a na?ve T cell into a Th17 cell leads to pro-inflammatory cytokine and chemokine production with subsequent myeloid cell recruitment to the inflamed tissue. Th17 response can be mitigated by T regulatory cells that secrete anti-inflammatory cytokines. Both T cell subsets need TGF-β for their differentiation and a characteristic plasticity in their phenotype may render them new therapeutic targets. In this review, we discuss the role of the Th17 pathway in NAFLD progression to NASH and to liver fibrosis analyzing different animal models of liver injury and human studies.  相似文献   
823.
Arterial stiffness estimated by pulse wave velocity (PWV) is an independent predictor of cardiovascular morbidity and mortality. Although recommended by the current guidelines, clinical applicability of this parameter is difficult, due to differences between the various techniques used to measure it and to biological variability. Our aim was to compare PWV assessed by 3 different commercially available systems. 100 subjects (51 ± 16 years, 45 men) were evaluated using the 3 methods: an oscillometric technique (Arteriograph, PWV-A); a piezo-electric method (Complior, PWV-C); and an high-resolution ultrasound technique implemented with an Echo-tracking system (Aloka, PWV-E). Conventional biological markers were measured. Correlations of PWV measured by the 3 methods were poor (r = 0.39, r = 0.39, and r = 0.31 for PWV-A vs. PWV-C, PWV-A vs. PWV-E, and PWV-C vs. PWV-E, respectively, all p < 0.05). By Bland–Altman analysis, mean difference (±SD) of PWV-A vs. PWV-C was ?1.9 ± 2.0 m/s, of PWV-A vs. PWV-E ?3.6 ± 1.9 m/s, and of PWV-C vs. PWV-E ?2.7 ± 1.9 m/s, with a wide coefficient of variation (22.3, 25.7, and 25.7 %, respectively). As expected, PWV-A, PWV-C, and PWV-E correlated with other arterial stiffness parameters, such as intima-media thickness (r = 0.22, r = 0.22, and r = 0.36, respectively), E p (r = 0.37, r = 0.26, and r = 0.94, respectively), and augmentation index measured by Arteriograph method (r = 0.66, r = 0.35, and r = 0.26, respectively); all p < 0.05. Assessment of PWV is markedly dependent on the technique used to measure it, related to various methods for measuring traveled distance of the arterial wave. Our results suggest the urgent need to establish reference values of PWV for each of these techniques, separately, to be used in routine clinical practice.  相似文献   
824.
CONTEXT: gamma-Aminobutyric acid (GABA) is a dominant inhibitory neurotransmitter involved in the modulation of brain electric activity and puberty onset in primates. GABA inhibitory effects on GnRH neurons are mainly mediated by GABA-A receptor alpha1-subunit. OBJECTIVE: The objective of this study was to investigate functional mutations or polymorphisms of the GABA-A receptor alpha1-subunit gene (GABRA1) in girls with idiopathic gonadotropin-dependent precocious puberty (GDPP) with and without electroencephalographic (EEG) abnormalities. DESIGN: The entire coding region of GABRA1 was sequenced in all patients. Two known GABRA1 polymorphisms were investigated by GeneScan software analysis or enzymatic restriction. Seventy-three normal women were used as controls for genetic study. EEG tracings were recorded in 23 girls with GDPP and 17 girls with adequate pubertal development. SETTING: The study was performed at a university hospital. PATIENTS: Thirty-one girls from 28 unrelated families with idiopathic GDPP were studied. RESULTS: Automatic sequencing revealed no functional mutations in girls with GDPP. Seven different GABRA1 polymorphisms, including two exonic (156T>C and 1323G>A) and five intronic [IVS2-712(GT)n, IVS3+12A>T, IVS8+45T>G, IVS9+76A>G, and IVS10+15G>A], were found in GDPP girls and controls. Abnormal EEG tracings were found in 26% of 23 girls with GDPP, two of them with epilepsy. The genotype and allele frequencies of the GABRA1 polymorphisms were not statistically different between unrelated GDPP girls and controls or between GDPP girls with or without EEG abnormalities. CONCLUSIONS: GABRA1 functional mutations or polymorphisms are not associated with the intrinsic mechanism of GDPP in girls with and without EEG abnormalities.  相似文献   
825.
BACKGROUND: Irritable bowel syndrome is commonly accepted as a disorder closely influenced by affective factors, which can either trigger the symptoms or contribute to their persistence, independently from their aetiology. It has been previously documented that irritable bowel syndrome patients respond to a variety of emotional states (anger, fear and anxiety) with an increase in colonic motility. AIMS: The aim of this study was to evaluate the experience and the expression of anger and the prevalent ego-defence mechanisms in a group of non-psychiatric patients with irritable bowel syndrome. SUBJECTS: Fifty-two patients with irritable bowel syndrome (18 males, 34 females) and 100 healthy volunteers from the community (44 males, 56 females) matched for age, level of education and social-status were enrolled. METHODS: Assessment was conducted using the State-Trait Anger Expression Inventory and the Defence Mechanism Inventory. RESULTS: No important differences between the two examined groups were found using the State-Trait Anger Expression Inventory and Defence Mechanism Inventory. CONCLUSIONS: It can be hypothesised that stable personality features and habits, such as anger disposition and defence mechanisms, play only a marginal role in irritable bowel syndrome, while psychological and psychosocial influences may act as predisposing or precipitating factors which contribute to the pathogenesis or expression of irritable bowel symptoms.  相似文献   
826.
Metabolic Brain Disease - Alzheimer's disease (AD) is clinically characterized by a progressive loss of cognitive functions and short-term memory. AD patients present two distinctive...  相似文献   
827.
The currently used cutoff level for ACTH-stimulated 17- hydroxyprogesterone (17OHP) for the diagnosis of the nonclassical (NC) form of 21-hydroxylase deficiency (21OHD), established before molecular studies, is based on the mean + 2 SD of 17OHP levels of obligate heterozygotes. However, carriers of CYP21 mutations present variable ACTH-stimulated 17OHP levels, ranging from normal values up to 30 nmol/liter. The aim of this study was to determine whether ACTH-stimulated 17OHP levels in obligate carriers for 21OHD would be correlated with the impairment of the enzyme activity caused by these mutations, which would affect the 17OHP cutoff level for the diagnosis of the NC form. Fifty-nine parents of patients with the classical and NC forms of 21OHD had their DNA screened for the mutations found in the index case and were divided into three mutation groups according to the impairment of enzyme activity (A = 0%, B = 3%, and C > 20%). All parents carried mutations in one allele (29 of group A, 9 of group B, and 21 of group C). Blood samples were collected at baseline condition and 60 min after ACTH (250 microg i.v.) to measure 17OHP levels. The levels among groups A, B, and C were compared using the Kruskall Wallis test. ACTH-stimulated 17OHP levels identified 39% of the carriers (9 in group A, 2 in group B and 12 in group C). The mean +/- SD basal 17OHP levels in groups A, B, and C were: 2.94 +/- 1.89, 1.77 +/- 0.81 and 3.90 +/- 2.43 nmol/liter, respectively (P > 0.05) and for ACTH-stimulated levels were 12.6 +/- 7.2, 13.2 +/- 12.9 and 16.8 +/- 7.8 nmol/liter, respectively (P > 0.05). Two carriers presented ACTH-stimulated 17OHP levels between 30 and 45 nmol/liter and their entire CYP21 sequencing revealed only one mutation in heterozygous state indicating that the current cutoff level might overestimate the diagnosis of the NC form. We conclude that the variable ACTH-stimulated 17-OHP levels in carriers are not related to CYP21 gene mutations with different impairment of enzyme activity.  相似文献   
828.
The effects of neonatal hypothyroidism on the number of Leydig cells were studied in neonatal Wistar rats. Moderate or severe hypothyroidism were induced during neonatal life by giving different amounts of methimazole (MMI; 0.05% or 0.1%) in the drinking water of pregnant and lactating dams. Rats were sacrificed on day 21 of postnatal life. Severely hypothyroid rats had approximately 45-fold higher serum thyrotropin (TSH) values and demonstrated approximately a 65% decrease in testes weight (p < 0.05) and the number of Leydig cells. However, in moderately hypothyroid rats, in which serum TSH was only approximately 16-fold higher, testicular weight was normal and the number of Leydig cells almost doubled (p < 0.01). There were no significant differences between the serum-free testosterone levels of the moderately and severely hypothyroid rats versus controls. Serum levels of 3alpha-androstanediol glucuronide, although decreased to less than 10% in severely hypothyroid rats (p < 0.01), were not changed by mild hypothyroidism. The number of Sertoli cells was increased in moderately hypothyroid rats versus controls (p < 0.05) and even further increased in severely hypothyroid rats (p < 0.05). We conclude that (1) severe neonatal hypothyroidism impairs the development and function of the testes and (2) moderate neonatal hypothyroidism stimulates the proliferation of Leydig cells.  相似文献   
829.
OBJECTIVE: Bilateral inferior petrosal sinus sampling (BIPSS) with corticotrophin-releasing hormone (CRH) stimulation is currently the gold standard test for the differential diagnosis of ACTH-dependent Cushing's syndrome. Reports on the use of desmopressin in this approach are limited. The aim of this study was to evaluate the use of desmopressin during BIPSS in a cohort of patients with ACTH-dependent Cushing's syndrome. DESIGN: A retrospective case-record study. PATIENTS: Fifty-six patients with confirmed ACTH-dependent Cushing's syndrome underwent BIPSS with desmopressin stimulation when presenting negative pituitary tumour imaging. MEASUREMENTS: Central to peripheral (CEN:PER) ACTH gradient, lateralization of the ACTH source and surgical tumour confirmation were evaluated. RESULTS: A CEN:PER ACTH gradient was found in 40 patients under basal conditions (CEN:PER >or= 2) and in 47 patients after desmopressin stimulation (CEN:PER >or= 3). Ectopic ACTH-producing tumours (three lung carcinoid tumour, one thymus carcinoid tumour and one thymus hyperplasia) were confirmed in five out of nine patients without the CEN:PER ACTH gradient, and four cases were false negative for Cushing's disease. Lateralization (IPS:IPS >or= 1.4) was observed in 80.8% of patients under basal conditions (38/47) and in 97.8% after desmopressin (46/47), and it was surgically confirmed in 78.7%. There were no false-positive cases. Sensitivity and specificity were 92.1% and 100%, respectively. CONCLUSIONS: Desmopressin improves the differential diagnosis of ACTH-dependent Cushing's syndrome by amplifying the CEN:PER and IPS:IPS ACTH gradients, and is therefore a useful ACTH secretagogue in BIPSS.  相似文献   
830.
Onychomycoses constitute pathologies frequently seen in dermatological practice worldwide. Usually, they are caused by two groups of pathogenic fungi: dermatophytes and yeasts of the Candida genus. However, in a small fraction of the cases, the etiologic agents comprise nondermatophyte molds, belonging to several genera and species. The objective of this study was to present two cases of onychomycosis associated to the mold Scytalidium dimidiatum in patients residing in two cities of Santa Catarina State, Brazil. Aspects of fungal pathogenesis, as well as the epidemiological characteristics and laboratory diagnosis, are discussed.  相似文献   
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