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111.

Introduction

Connexin 43 (Cx43) mediates the effect of thyroid hormone on Sertoli cell maturation in vitro. We investigated the influence of triiodothyronine (T3) administration on Cx43 expression in relation to the progress in seminiferous tubule maturation.

Material and methods

Male rats were daily injected with 100 µg T3/kg body weight from birth until postnatal day (pnd) 5 (transient treatment – tT3) or until pnd 15 (continuous treatment – cT3) or solvent – control (C). On pnd 16 serum hormone levels, body and testes weight, seminiferous tubule morphometry, Cx43 immunostaining and germ cell degeneration were investigated. Cx43 expression was also assessed in six 50-day-old adult untreated rats.

Result

tT3 increased 2.6-fold serum level of T3, testes weight, and seminiferous tubule diameter, and induced maturation-like dislocation of Cx43 expression from the apical to the peripheral region of Sertoli cell cytoplasm. In addition, incidence of Cx43-positive tubules declined from 86% in C to 46% after tT3, being similar to the adult value (30% of tubules Cx43-positive). In turn, cT3 increased serum T3 level 12-fold, and decreased body weight. Seminiferous tubules became shortened and distended, Sertoli cell cytoplasm vacuolated, Cx43 expression had minimal intensity and germ cell degeneration increased.

Conclusions

Cx43 might intermediate a short and transient stimulatory effect of T3 on seminiferous tubule maturation that disappeared together with exposure to the toxic effect of a continuously high level of the hormone.  相似文献   
112.

Introduction

Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) expression are crucial in the biology of breast carcinoma. HER-2/neu gene is amplified and overexpressed in 15-30% of invasive breast cancers. HER-2-positive breast cancers have worse prognosis than HER-2 negative tumors and possess distinctive clinical features. The aim of this study was to assess the expression of HER2 in cancer tissue of patients with invasive breast cancer in correlation with tumor type, histological grade, tumor size, lymph node status, and expression of estrogen receptor and progesterone receptor.

Material and methods

Formalin-fixed, paraffin-embedded tissues from 40 patients with invasive HER-2-positive breast cancer and from 191 patients with HER-2-negative breast cancer were used in this study. HER2 expression was determined using the test HerceptTest™ DAKO.

Results

Among 231 cases of breast cancer, 18 invasive lobular carcinomas and 213 invasive ductal carcinomas were diagnosed. Sixty percent of HER-2-positive breast cancers were ER-positive compared with 77% in the HER-2-negative group (p = 0.002). The expression of PR was observed in 43% of HER-2-positive breast cancers and in 72% of HER2-negative tumors (p = 0.003). Excessive expression of HER2 protein was detected in 60% of patients positive for estrogen receptors, which may worsen prognosis in these patients.

Conclusions

Determination of HER2 overexpression in breast cancer patients, allows for a determination of a group of patients with a worse prognosis.  相似文献   
113.

Introduction

CD36 plays an important role in long-chain fatty acid homeostasis in skeletal muscle and the myocardium. CD36 deficiency may lead to reduced myocardial uptake of long-chain fatty acid. Therefore, different mutations of the CD36 gene may contribute to the clinical heterogeneity of cardiac hypertrophy.

Material and methods

The objective of the study was to investigate whether there is an association between the sequence changes in CD36 and echocardiographic and electrocardiographic parameters in Caucasian patients with early onset coronary artery disease. The study group comprised 100 patients. Electrocardiography and echocardiography were performed in all patients. Amplicons of exons 4 to 6 including fragments of introns were studied using the denaturing high-performance liquid chromatography technique.

Results

IVS3-6TC (rs3173798) heterozygotes had impaired left ventricle diastolic function. 573GA heterozygotes (rs5956) had higher frequency of pseudonormal left ventricular diastolic function and it was confirmed by the increase in wave A’ in the tissue Doppler. 591AT genotype was associated with borderline higher posterior wall end-diastolic thickness and lower E/A ratio. These results are consistent with electrocardiography parameters which could reflect left ventricular hypertrophy (higher RV5(6) and RV5(6) + SV1(2) parameters, depressed ST segments and tendency to longer Qtc II interval) in 591AT heterozygotes.

Conclusions

Detected variant alleles of CD36 may be associated with features of left ventricular hypertrophy and impaired diastolic function.  相似文献   
114.
115.
This 2-year trial evaluated the efficacy and tolerability of a monthly oral regimen of risedronate. Postmenopausal women with osteoporosis were randomly assigned to double-blind treatment with risedronate 75 mg on 2 consecutive days each month (2CDM) or 5 mg daily. The primary end point was the percentage change from baseline in lumbar spine bone mineral density (BMD) at 12 months. Secondary end points included the change in BMD of the lumbar spine and proximal femur and in bone turnover markers as well as the number of subjects with at least one new vertebral fracture over 24 months. Among 1,229 patients who were randomized and received at least one dose of risedronate, lumbar spine BMD was increased in both treatment groups: mean percentage change from baseline was 4.2 ± 0.19 and 4.3 ± 0.19 % in the 75 mg 2CDM and 5 mg daily groups, respectively, at month 24. The treatment difference was 0.17 (95 % confidence interval ?0.35 to 0.68). There were no statistically significant differences between treatment groups on any secondary efficacy parameters. Both treatment regimens were well tolerated. Risedronate 75 mg 2CDM was noninferior in BMD efficacy and did not show a difference in tolerability compared to 5 mg daily after 24 months of treatment in women with postmenopausal osteoporosis. This monthly regimen may provide a more convenient dosing schedule to some patients with postmenopausal osteoporosis.  相似文献   
116.
Treatment with continuous subcutaneous insulin infusion (CSII) allows a large degree of treatment individualization and intensification in children with diabetes. The study's aim was to evaluate the impact of treatment with CSII on glycated haemoglobin level (HbA1c) in children with diabetes and investigate whether introduction of CSII is associated with an increased risk of acute complications of diabetes. Patients treated throughout the recruitment period exclusively with multiple daily injections (MDI) were matched for duration of diabetes and HbA1c level at baseline with patients treated exclusively with CSII in a 1:1 group ratio (n?=?223 and 231 for MDI and CSII, respectively). The CSII group showed lower HbA1c after the observation period (7.98?±?1.38 vs. 7.56?±?0.97; P?=?0.002). HbA1c variability measured as standard deviations of average values was also lower in the CSII group (0.73?±?0.45 vs. 0.84?±?0.54; P?=?0.049). The rate of hospitalization due to acute events was similar in both groups (14.7/100 vs. 14.0/100 person/years in the MDI and CSII group, P?=?0.72). Duration of hospital stay per year was on average 1.25?days shorter in the CSII group (P?=?0.0004), but the risk of acute complications resulting in hospitalization did not differ between the groups (hazard ratio (HR) 1.16; 95% confidence interval (95% CI) 0.68-1.63). The most significant risk factor for hospitalization due to acute complications was baseline HbA1c concentration (HR 1.25; 95% CI 1.14-1.37). In conclusion, CSII treatment may improve glycemic control and reduce its variability. Change of MDI to CSII does not alter the risk of hospitalization and may reduce the annual duration of hospitalization in children with diabetes.  相似文献   
117.
118.
Hypertension (HTN) is common in pediatric recipients following kidney transplantation (KT). We retrospectively assessed the impact of HTN on long‐term (>10‐yr) outcomes in pediatric KT recipients (aged < 18 yr) at our center. Two hundred and ninety‐three pediatric KT recipients (83% living donor [LD]) with graft survival (GS) for ≥5 yr were studied. HTN was defined by antihypertensive medication use at five yr post‐KT. One hundred and sixty (55%) recipients did not have HTN, and 133 (45%) had HTN at five yr post‐KT. There were no differences in actuarial patient survival between cohorts. Actuarial GS at 15 and 20 yr was 68% and 53% for recipients without HTN, and 53% and 33% for recipients with HTN (p = 0.006). Among LD recipients using one antihypertensive, GS at 15 yr was 100% for those using an angiotensin‐converting enzyme inhibitor (ACEI) and 44% for those not using an ACEI (p = 0.04). Among these recipients, HTN treated with no ACEI was a significant risk factor for graft failure at >5 yr (hazard ratio [HR] = 2.5, p = 0.02), but HTN treated with an ACEI was not (HR = 0.6, p = 0.7). HTN at five yr post‐KT is associated with poorer long‐term GS in pediatric recipients, but ACEI therapy may enable better outcomes and should be studied further.  相似文献   
119.
The aim of the study was to present consecutive stages of the posterior petrosal approach (PPA).Eighteen simulations of PPA were performed on non-fixed human cadavers without any known pathologies in the head and neck. The consecutive stages of the procedure were documented with photographs and schemes.The starting point for PPA is a temporal craniotomy, suboccipital craniectomy and mastoidectomy with keeping the bony labyrinth intact. Approach to the middle part of the clivus is achieved by raise of the temporal lobe and section of the superior petrosal sinus and tentorium and by mobilization the sigmoid sinus.Posterior petrosal approach is a reproducible technique, which provides surgical penetration of the middle clivus and related regions. It reduces the operating distance and allows to limit the cerebellum and temporal lobe traction and to preserve the anatomic integrity of the brain stem and cranial nerves of the cerebellopontine angle.  相似文献   
120.
A cinnamamide scaffold has been successfully incorporated in several compounds possessing desirable pharmacological activities in central and peripheral nervous system such as anticonvulsant, antidepressant, neuroprotective, analgesic, anti‐inflammatory, muscle relaxant, and sedative/hypnotic properties. R,S‐(2E)‐1‐(3‐hydroxypiperidin‐1‐yl)‐3‐phenylprop‐2‐en‐1‐one (KM‐608), a cinnamamide derivative, was synthesized, its chemical structure was confirmed by means of spectroscopy and crystallography, and additionally, thermal analysis showed that it exists in one crystalline form. The compound was evaluated in vivo in rodents as anticonvulsant, antiepileptogenic, analgesic, and neuroprotective agent. The beneficial properties of the compound were found in animal models of seizures evoked electrically (maximal electroshock test, 6‐Hz) and chemically (subcutaneous pentylenetetrazole seizure test) as well as in three animal models of epileptogenesis: corneal‐kindled mice, hippocampal‐kindled rats, and lamotrigine‐resistant amygdala‐kindled rats. Quantitative pharmacological parameters calculated for the tested compound were comparable to those of currently used antiepileptic drugs. In vivo pharmacological profile of KM‐608 corresponds with the activity of valproic acid.  相似文献   
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