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1.
Experiments were conducted to assess whether changing dietary fat composition altered phospholipid composition of rat testicular plasma membranes in a manner that altered receptor-mediated action of luteinizing hormone (LH)/human chorionic gonadotropin (hCG). Weanling rats were fed diets that provided high or low cholesterol intakes and that were enriched with linseed oil, fish oil or beef tallow for 4 wk. Feeding diets high in (n-3) fatty acids decreased plasma and testicular plasma membrane 20:4(n-6) content. A marked reduction of the 22:5(n-6) content and an increase in the 22:6(n-3) content of testicular plasma membrane was found only in animals fed fish oil. A decrease in binding capacity of the gonadotropin (LH/hCG) receptor in the plasma membrane, with no change in receptor affinity, was observed for animals fed either linseed oil or fish oil diets. Dietary treatments that raised plasma membrane cholesterol content and the cholesterol to phospholipid ratio in the membrane were associated with increased binding capacity of the gonadotropin receptor. Feeding diets high in 18:3(n-3) vs. those high in fish oil altered receptor-mediated adenylate cyclase activity in a manner that depended on the level of dietary cholesterol. Feeding diets high in cholesterol or fish oil increased basal and LH-stimulated testosterone synthesis relative to that in animals fed the low cholesterol diet containing linseed oil. It is concluded that changing the fat composition of the diet alters the phospholipid composition of rat testicular plasma membranes and that this change in composition influences membrane-mediated unmasking of gonadotropin receptor-mediated action in testicular tissue.  相似文献   
2.
The immune response to local in vivo inhalation of a lysed bacteria vaccine was assessed in surgical specimens of main-stem bronchi from patients who had undergone pneumectomy for cancer. The patient population included 22 subjects; 11 of these received the aerosol vaccine twice a day for 10 days prior to surgery, while the remaining 11 patients were used as controls and were not immunized. The submucous glands of immunized subjects showed significantly more cells than did those of the controls, i.e., 62 +/- 8 versus 37 +/- 7, respectively (P less than 0.05). The following five antigens were chosen for study by fluorescence assay: Streptococcus pneumoniae types II and III, Haemophilus influenzae, Streptococcus sp. strain D19, and Klebsiella pneumoniae. An immunization-dependent correlation was found between immunoglobulin A, immunoglobulin A-bearing cells, and specific antibody-bearing cells on the one hand and three of the five antigens (S. pneumoniae types II and III and Streptococcus sp. strain D19) on the other hand. This is the first time that a relationship has been established between bacterial immunization of the lower respiratory tract and local immunoglobulin production in humans.  相似文献   
3.
The purpose of this study was comparison of VEGF (vascular endothelial growth factor) levels in serum and pleural fluid and estimation of this test usefulness in diagnosis of pleural effusions. VEGF levels were measured by ELISA method in 68 patients (45 males and 23 females) aged 19-81 years. By Light's criteria in 16 cases transudate and in 52 cases exudate was recognized. By means of fluid cytology, pleural biopsy, microbiology or thoracoscopy in 10 cases pleural metastases from distant organs, in 15 cases coexisting pulmonary neoplasm, in 11 cases mesothelioma and in 16 cases tuberculosis were determined as a cause of fluid accumulation in pleural space. The mean VEGF levels were significantly higher (p < 0.001) in patients with exudates than in patients with transudates (3833 pg/ml and 325 pg/ml respectively). Based on likelihood ratios analysis, as a cut off value in differentiation of exudates and transudates a value 700 pg/ml was accepted. The sensitivity of this test was 75% and the specificity 93% and likelihood ratio (LR) 12.5. The mean VEGF level in exudates was seven times higher than mean VEGF level in serum (3833 pg/ml and 573 pg/ml respectively). Mean VEGF levels in malignant exudates (4615 pg/ml) were significantly higher than in tuberculous exudates (2073 pg/ml). As a cut off value in differentiation between malignant and tuberculous exudates a value of 4500 pg/ml was accepted. We conclude that our results suggests the local VEGF production in pleural cavity and the significant role of this cytokine in pleural exudates accumulations and also suggests the usefulness of VEGF estimation in pleural fluid in differentiation transudates from exudates and malignant from tuberculous pleural fluids.  相似文献   
4.
Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure with a prevalence of 1:2500. There are several primary and secondary etiologic factors, including gene mutations, infection agents, particularly viruses, toxins, autoimmune, and systemic disorders, and pheochromocytoma, neuromuscular, metabolic, mitochondrial, and nutritional disorders. However, a precise diagnosis can be reached only in no more than 50% of all cases. Herein, we report a rare case of hepatic damage and severe DCM as a consequence of relatively popular socially used narcotic-Ecstasy (3,4-methylenedioxy-N-methylamphetamine [MDMA]).  相似文献   
5.
The tongue of the white tailed eagle is elongated with a sharp-ended apex. The length of the tongue is 6 cm. The characteristic morphological features observed on the body of the tongue include a distinct median groove dividing the mucosa into two symmetrical, convex lateral parts and a single crest of large conical papillae in the posterior part of the lingual body, extending over the surface of the flat root of the tongue. The mucosa of the lingual body and root is covered by the parakeratinized multilayered epithelium. The horny layer in the mucosal epithelium was observed in the median groove, on the conical papillae and on the ventral surface of the tongue. The observations of the three dimensional structure of the subepithetial connective tissue revealed the presence of a system of laminae or smaller interconnected ridges, depending on the area of the tongue. In the white tailed eagles the anterior and posterior lingual glands were distinguished. The glands consist of several alveolar-tubular secretory units and a subepithelial chamber collecting the mucous secretion. The orifices of the anterior glands are situated on the lateral surfaces of the posterior part of the lingual body, whereas the posterior lingual glands open on the entire surface of the lingual root.  相似文献   
6.
The endocannabinoid system (ECS) is an endogenous signaling system formed by specific receptors (cannabinoid type 1 and type 2 (CB1 and CB2)), their endogenous ligands (endocannabinoids), and enzymes involved in their synthesis and degradation. The ECS, centrally and peripherally, is involved in various physiological processes, including regulation of energy balance, promotion of metabolic process, food intake, weight gain, promotion of fat accumulation in adipocytes, and regulation of body homeostasis; thus, its overactivity may be related to obesity. In this review, we try to explain the role of the ECS and the impact of genetic factors on endocannabinoid system modulation in the pathogenesis of obesity, which is a global and civilizational problem affecting the entire world population regardless of age. We also emphasize that the search for potential new targets for health assessment, treatment, and the development of possible therapies in obesity is of great importance.  相似文献   
7.
The growing popularity of health education on social media indicates the need for its appropriate evaluation. This paper aims to present the potential of the Kirkpatrick Model (KM) with New World Kirkpatrick Model (NWKM) additions to evaluate the nutritional education provided by dieticians via Instagram. Instagram profiles of ten dieticians providing nutritional education for their followers were analyzed in March and April 2021. The study sample included profiles of both macro- and micro-influencers. The analyzed quantitative data included Instagram Engagement Rate and the number of likes and comments per post. The qualitative analysis of the comments was performed following the theoretical framework provided by the KM and NWKM. Collected data showed followers’ satisfaction, commitment, and relevance of the presented content, fulfilling the Level 1 of NWKM. Level 2 of NWKM was represented by 4 out of 5 dimensions (knowledge, attitude, confidence, commitment). No comments were found only for skills. Both Levels 3 (Behavior) and 4 (Results) of the KM were met. However, the use of the NWKM for them seems limited. The KM can be used to evaluate nutritional education on social media. The NWKM additions seem applicable mostly for Levels 1 and 2.  相似文献   
8.
The occurrence of childhood obesity is influenced by both genetic and epigenetic factors. FTO (FTO alpha-ketoglutarate dependent dioxygenase) is a gene of well-established connection with adiposity, while a protooncogene PLAG1 (PLAG1 zinc finger) has been only recently linked to this condition. We performed a cross-sectional study on a cohort of 16 obese (aged 6.6–17.7) and 10 healthy (aged 11.4–16.9) children. The aim was to evaluate the relationship between methylation and expression of the aforementioned genes and the presence of obesity as well as alterations in anthropometric measurements (including waist circumference (WC), body fat (BF_kg) and body fat percent (BF_%)), metabolic parameters (lipid profile, blood glucose and insulin levels, presence of insulin resistance) and blood pressure. Expression and methylation were measured in peripheral blood mononuclear cells using a microarray technique and a method based on restriction enzymes, respectively. Multiple regression models were constructed to adjust for the possible influence of age and sex on the investigated associations. We showed significantly increased expression of the FTO gene in obese children and in patients with documented insulin resistance. Higher FTO expression was also associated with an increase in WC, BF_kg, and BF_% as well as higher fasting concentration of free fatty acids (FFA). FTO methylation correlated positively with WC and BF_kg. Increase in PLAG1 expression was associated with higher BF%. Our results indicate that the FTO gene is likely to play an important role in the development of childhood adiposity together with coexisting impairment of glucose-lipid metabolism.  相似文献   
9.
CONTEXT: Given the level of unintended pregnancy in the United States, it is somewhat surprising that hormonal implants and injectables-methods that are long-acting, reversible, highly effective and convenient--have not attained the popularity enjoyed by other medical methods. Knowing the reasons why women have so far spurned these methods might lead to the design and implementation of interventions and targeted social marketing to promote their use. METHODS: Data from the 1993 and 1995 rounds of the National Survey of Women are used to examine the reasons women gave for not having used the implant or injectables, whether they intended to use these methods and how their attitudes toward them may influence their decision to use such methods in the future. Logistic regression models were used to identify the social and demographic characteristics that influence women's decisions not to use these methods. RESULTS: Fewer than 2% of women who were at risk of an unintended pregnancy in 1995 were using the implant, and under 3% were using the injectable. Women gave three major reasons for not using either of these methods: lack of knowledge; fear of side effects or health hazards; and satisfaction with the method they were currently using. Age, education, marital status, parity and current contraceptive method strongly predicted fear of side effects, lack of knowledge and satisfaction with the current method as reasons for not using the implant or the injectable. For example, women aged 30 or older and those with a college education were half as likely as younger women and those with no college education to mention fear of side effects as their main reason for not using the implant. Likewise, single women, women with one or more children and those using a barrier method were 2-3 times as likely as married women, childless women and those using a medical method to attribute nonuse to the implant's side effects. Few women said they intended to use these methods in the next 12 months: 5% for the implant and 10% for the injectable. Single women, women with no college education, women with children, women wanting to have a child (or another child) and women with positive attitudes toward the effect of using an injectable were significantly more likely to say they intended to use the injectable. Nevertheless, substantial proportions of women reported quite negative attitudes about these methods. CONCLUSIONS: The low prevalence of use and the low level of use intention for the implant and for injectables raise questions about the promise for the future of these methods. Each method seems to appeal to certain subgroups of women, however. Thus, if proper interventions and social marketing are targeted to such groups, they may be disabused of misperceptions regarding these methods and possibly become more willing to try them.  相似文献   
10.
The identification of a sub-endocardial infarction is of major interest in cardiology. This study evaluates the sensitivity of selected measures to the thickness of such an infarction. Synthetic ultrasonic data (long-axis view) of left ventricular models with inclusions were generated using Field II and meshes obtained from finite-element simulations, which also provided the reference for the estimates obtained from ultrasonic data. The displacements, the first and second component of the principal strain (ε1 and ε2), and several measures derived from these quantities were estimated. All estimates, except for the poorly estimated ε2, exhibited sensitivity to the presence and transmurality of the inclusion. The most sensitive was the gradient of the averaged transmural profiles of ε1, and ε1 averaged over the area corresponding to the transmural inclusion. The inflection point of the ε1 profile shifted toward the outer wall with increasing thickness of the non-transmural inclusion.  相似文献   
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