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81.
The effects of the dietary Ca and P ratio, independent of any vitamin D effects, on bone mineralization and turnover was examined in 60 VDRKO mice fed different Ca/P ratio diets. High dietary Ca/P ratio promoted bone mineralization and turnover with adequate intestinal Ca and P transports in VDRKO mice. INTRODUCTION: To clarify the effects of the dietary calcium (Ca) and phosphorus (P) ratio (Ca/P ratio) on bone mineralization and turnover in null-vitamin D signal condition, vitamin D receptor knockout (VDRKO) mice were given diets containing different Ca/P ratios. MATERIALS AND METHODS: Five groups of 4-week-old VDRKO mice, 10 animals each, were fed diets for 4 weeks. Group 1 was wild-type littermate mice, fed the diet containing 0.5% Ca and P (Ca/P = 1). Group 2 was the control and was fed a similar diet (Ca/P = 1). Groups 3, 4, 5, and 6 were fed the following diets: 0.5% Ca and 1.0% P (Ca/P = 0.5), 1.0% Ca and 1.0% P (Ca/P = 1), 1.0% Ca and 0.5% P (Ca/P = 2), and 0.5% Ca and 0.25% P (Ca/P = 2). RESULTS AND CONCLUSIONS: Compared with group 2, serum calcium and phosphorus levels in groups 4-6 significantly increased. Serum parathyroid hormone levels increased in group 3 and decreased in group 5. The amounts of intestinal calcium absorption decreased in groups 3 and 4. Phosphorus absorption increased in group 3 and decreased in groups 4-6. Bone mineral content (BMC) and bone mineral density (BMD) of the femur in group 3 significantly decreased and increased in group 5. In the primary spongiosa of the proximal tibia, the trabecular bone volume (BV/TV) and osteoid thickness (O.Th) in group 3 significantly increased, and decreased in group 6. In groups 5 and 6, the numbers of the trabecular osteoclasts increased. In groups 2 and 4, and the secondary spongiosa was identified in 5 of 10 mice. In group 3, there was no secondary spongiosa in either mouse. Osteoid maturation time (OMT) significantly decreased, and bone formation rate (BFR/BS) increased in groups 4-6. These data indicate that the dietary Ca/P ratio regulates bone mineralization and turnover by affecting the intestinal calcium and phosphorus transports in VDRKO mice. They may suggest the existence of Ca/P ratio-dependent, vitamin D-independent calcium and phosphorus transport system in the intestine.  相似文献   
82.
OBJECTIVE: The purpose of this study was to analyze the behavior of the mitral valve ring and the left ventricle in dilated cardiomyopathy. METHODS: We analyzed 68 fixed adult human hearts, divided into 48 hearts with dilated cardiomyopathy of ischemic or idiopathic origin and 20 hearts free of pathologic heart conditions. Digital images of the mitral ring perimeter, attachment of the anterior and posterior leaflets, and fibrous and muscular portions were collected. We also measured the internal perimeter of the left ventricle, the distance from the septum to the anterior and posterior papillary muscles, the distance between the papillary muscles, and the extension of interventricular septum. RESULTS: The analysis of the results showed proportional distribution of the ring's fibrous portion (r2 = 0.98) and muscular portion (r2 = 0.99) according to the degree of mitral valve dilation. Linear regression revealed that the perimeters of anterior and posterior leaflet attachments (r2 = 0.96 and r2 = 0.98, respectively) also had a proportional relation. We did not observe proportionality between the degree of dilation of the mitral ring and the left ventricle. It was observed that dilation of the left ventricle takes place globally in its segments. CONCLUSION: Differently from what was thought, in ischemic or idiopathic dilated cardiomyopathy, dilation of mitral ring is proportional and does not exclusively affect the posterior portion. The degree of left ventricular dilation does not determine the degree of dilation of the mitral ring because they are independent processes. These observations shed new light on the techniques used to correct mitral valve insufficiency in dilated cardiomyopathy.  相似文献   
83.
BACKGROUND: Patients presenting sickle cell disease may develop different types of hepatic complications. Intrahepatic cholestasis is a potentially fatal complication of the disease, and sometimes the only possible solution is transplantation. Postoperative transfusion management has not yet been well established. In this report, we describe the transfusional program of a patient presenting sickle cell disease and intrahepatic cholestasis who underwent liver transplantation 2 years ago. METHODS: Data were obtained from the chart and the blood bank records. RESULTS: The liver transplantation was performed successfully. Despite mild allograft dysfunction 3 months after surgery, secondary to intrahepatic sickling, the patient has been doing well with the transfusional management adopted (sickle-cell hemoglobin <20%). CONCLUSION: Sickle cell disease should not be a criterion for exclusion from liver transplantation. Regular transfusion with monitoring of sickle-cell hemoglobin is a very important measure to minimize the risk of intrahepatic sickling and possible rejection.  相似文献   
84.
Kowalski LP  Carvalho AL 《Head & neck》2002,24(10):921-924
BACKGROUND: The use of selective neck dissection in a positive neck is still controversial. The object of this study was to ascertain the possibility of doing this procedure in oral cavity carcinoma with a single clinically metastatic lymph node smaller than 6 cm (N1 and N2a). PATIENTS AND METHODS: From 1970 to 1994, we analyzed 164 oral cavity cancer patients with clinically N1 or N2a stage cancer submitted to radical neck dissection. RESULTS: The histologic findings did not confirm a metastatic lymph node in 69 (42.1%) cases (pN0) and showed multiple lymph nodes in 19 (11.6%) cases. Moreover, just one patient (0.6%) had a metastatic lymph node at level IV (one case with multiple lymph nodes) and none at level V. CONCLUSIONS: Because we did not find a single metastatic lymph node at levels IV and V and there was a high incidence of pN0 (57.4%) in patients with clinical N1 stage at level I, these patients could be candidates for a supraomohyoid neck dissection (extended or not to level IV) instead of radical neck dissection.  相似文献   
85.
Several neurotransmitter systems have been related to developmental processes during the past decade. In this review, we discuss the evidence that the nicotinic acetylcholine receptors could have an additional function during development that may be unrelated to their role in cholinergic neurotransmission in the vertebrate brain. Both temporal expression data and in vitro and in vivo studies with nicotinic agonists and antagonists have provided direct support for a role of nicotinic receptors in neural developmental processes such as neurite outgrowth and differentiation. A similar picture has emerged for other neurotransmitter and receptor systems as well, which generates a new view of neural processes during both development and mature life.  相似文献   
86.

Objectives

To evaluate the influence of bilateral or left sympathectomy on left ventricular remodeling and function after myocardial infarction in rats.

Methods

Myocardial infarction was induced in rats by ligation of the left anterior descending coronary. Seven days later, rats were divided into 4 groups: the myocardial infarction, myocardial infarction with left sympathectomy, myocardial infarction with bilateral sympathectomy, and sham groups. After 8 weeks, left ventricular function was evaluated with the use of a pressure-volume conductance catheter under steady-state conditions and pharmacological stress. Infarct size and extracellular matrix fibrosis were evaluated, and cardiac matrix metalloproteinases and myocardial inflammatory markers were analyzed.

Results

The myocardial infarction and left sympathectomy group had an increased end diastolic volume, whereas the bilateral sympathectomy group had a mean end-diastolic volume similar to that of the sham group (P < .002). Significant reduction in ejection fraction was observed in the myocardial infarction and left sympathectomy group, whereas it was preserved after bilateral sympathectomy (P < .001). In response to dobutamine, left ventricular contractility increased in sham rats, rising stroke work, cardiac output, systolic volume, end-diastolic volume, ejection fraction, and dP/dt max. Only bilateral sympathectomy rats had significant increases in ejection fraction (P < .001) with dobutamine. Fibrotic tissue and matrix metalloproteinase expression decreased in the bilateral sympathectomy group compared to that in the myocardial infarction group (P < .001) and was associated with left ventricular wall thickness maintenance and better apoptotic markers in noninfarcted myocardium.

Conclusions

Bilateral sympathectomy effectively attenuated left ventricular remodeling and preserved systolic function after myocardial infarction induction in rats.  相似文献   
87.
Die Anaesthesiologie - Simulationstraining ist für die Notfallmedizin unverzichtbar, insbesondere in Hinsicht auf eine verbesserte Patientensicherheit. Methoden und Technologien umfassen ein...  相似文献   
88.
Even though very precise at describing pelvic organ position, our criticism to the Pelvic Organ Prolapse Quantification (POP-Q) system is its limited ability to quantify the prolapse itself, since it still classifies prolapse into four stages, almost the same way as Baden and Walker (Clin Obstet Gynecol 15(4):1070-1072, 1972) did in 1972. As a result, the same grade can include a wide prolapse intensity range. The objective of this study was to assess inter-observer reliability in the Pelvic Organ Prolapse Quantification Index (POP-Q-I; Lemos et al., Int Urogynecol J 18(6):609-611, 2007) on a prospective randomized trial. Fifty consecutive women were prospectively examined by two members of the urogynecology staff, blinded to each other's results. Spearman's rank correlation was used to assess inter-observer reliability. Excellent correlation coefficients were observed, with an overall coefficient of 96.5% (CI: 0.889-1.042; p < 0.0001). The POP-Q-I is a method that makes POP research more efficient by directly measuring prolapse as a continuous variable, which is statistically more powerful than the categorical variables proposed by the POP-Q system. This study suggests that the POP-Q-I is applicable to clinical POP research.  相似文献   
89.

OBJECTIVE

To investigate the structural organization of the connective tissue in the corpus cavernosum (CC) adjacent to the fibrous plaque in Peyronie’s disease (PD) using stereological and biochemical techniques, as most studies on PD have focused on the analysis of the fibrous plaque that forms in the tunica albuginea (TA). Because this fibrotic reaction is mediated by various inflammatory soluble factors, adjacent connective tissues might also be affected and this secondary effect might explain, for example, the erectile dysfunction that occurs in PD.

PATIENTS AND METHODS

During surgery biopsies were taken from the CC adjacent to the fibrous plaque and from the plaque itself in seven patients with PD (mean age 48.3 years). All the patients had normal erections. Control samples were similarly located samples from ‘normal’ penises obtained during autopsy of five men (mean age 52.3 years). Tissue samples were stained with Weigert’s stain (elastic fibres), Van Gieson’s stain (connective tissue), and Sirius red (collagen). Stereological analysis was done using a 42‐point grid to determine volumetric densities (Vv). Total collagen content was estimated as micrograms of hydroxyproline per milligram dry CC.

RESULTS

The Vv of elastic fibres was significantly reduced in PD by 17.3% compared with controls, at a mean (sd ) of 19.49 (3.27)% vs 23.56 (1.87)% (P < 0.05). While in PD the Vv of smooth muscle at 34.46 (2.06)% and connective tissue at 35.39 (6.15)% were not significantly different from those of controls at 38.38 (3.17)% and 38.02 (5.03)%, respectively. The Vv of elastic fibres in the fibrous plaque was decreased by 38.3% compared with the normal TA, at 20.25 (5.49)% vs 32.81 (4.75)% (P < 0.02). The mean (sd ) collagen concentration in the CC from controls was 77.94 (24.26) µg/mg and in the patients with PD was 66.57 (19.39) µg/mg, which did not differ significantly. Sirius red‐stained sections under polarized light showed that, in the normal CC, collagen‐associated colours were homogeneously distributed. However, in the PD samples, stained collagen had a disrupted orientation and had a more heterogeneous birefringence, implying looser collagen bundles.

CONCLUSIONS

The quantitative analyses indicated that collagen in the CC close to the fibrous plaque was not affected, although its organization was noticeably altered. The CC elastic fibres were reduced though, and there was a similar change in the fibrous plaque of the TA. These results suggest that, although occurring primarily in the TA, the PD fibrous plaque may induce changes in the adjacent CC.  相似文献   
90.
Background  It has been proposed that there is improvement in glucose and insulin metabolism after weight loss in patients who underwent diet restriction and bariatric surgery. Methods  Eleven normal glucose tolerant (NGT) morbidly obese patients [body mass index (BMI), 46.1 ± 2.27 g/m2] and eight abnormal glucose metabolism (AGM) obese patients (BMI, 51.20 kg/m2) were submitted to diet-restriction and bariatric surgery. Prospective study on weight loss changes, over the glucose, insulin metabolism, glucagon-like peptide-1 (GLP-1), and adiponectin levels were evaluated by oral glucose tolerance test during three periods: T1 (first evaluation), T2 (pre-surgery), and T3 (9 months after surgery). Results  Insulin levels improved after surgery. T1 was 131.1 ± 17.60 pmol/l in the NGT group and 197.57 ± 57.94 pmol/l in the AGM group, and T3 was 72.48 ± 3.67 pmol/l in the NGT group and 61.2 ± 9.33 pmol/l in the AGM group. The major reduction was at the first hour of the glucose load as well as fasting levels. At 9 months after surgery (T3), GLP-1 levels at 30 and 60 min had significantly increased in both groups. It was observed that the AGM group had higher levels of GLP-1 at 30 min (34.06 ± 6.18 pmol/l) when compared to the NGT group (22.69 ± 4.04 pmol/l). Homeostasis model assessment of insulin resistance from the NGT and AGM groups had a significant reduction at periods T3 in relation to T1 and T2. Adiponectin levels had increased concentration in both groups before and after surgical weight loss. However, it did not have any statistical difference between periods T1 vs. T2. Conclusions  Weight loss by surgery leads to improvement in the metabolism of carbohydrates in relation to sensitivity to the insulin, contributing to the reduction of type 2 diabetes incidence. This improvement also was expressed by the improvement of the levels of adiponectin and GLP-1.  相似文献   
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