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51.
52.
Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine.  相似文献   
53.
A cross sectional study assessed the bone mineral density (BMD) of 20 young adult patients who received a renal transplantation in childhood. The BMD of the lumbar spine, mainly trabecular bone, and of the total body, mainly cortical bone, were measured and expressed as an SD score. Fourteen patients (70%) had a BMD SD score of the lumbar spine below -1, of whom six patients were below -2. Fifteen patients (75%) had a BMD SD score of the total body below -1, of whom seven patients were below -2, Both trabecular and cortical bone appeared to be involved in the osteopenic process. The cumulative dose of prednisone was inversely correlated to both lumbar spine and total body BMD SD score. In a multiple regression analysis the cumulative dose of prednisone appeared to be the only factor with a significant effect on BMD SD score. Most young adult patients who had received a renal transplantation in childhood had moderate to severe osteopenia. Corticosteroid treatment played a major part in the development of osteopenia in these patients.  相似文献   
54.
BACKGROUND: Folliculotropic mycosis fungoides (MF) is a rare variant of cutaneous T-cell lymphoma, MF type, characterized by atypical lymphocytes preferentially infiltrating the hair-follicle epithelium relative to the epidermis. OBSERVATIONS: We describe a rare case of folliculotropic MF involving the central nervous system. This is also the first case in which laser capture microdissection was used to show that the atypical lymphocytes within the hair-follicle epithelium were part of the same tumor clone present in other tissue compartments. CONCLUSIONS: In reviewing the literature describing atypical lymphocytes infiltrating hair-follicle epithelium relative to the epidermis, we encourage the use of the term folliculotropic mycosis fungoides. Our case also supports previous findings that central nervous system involvement can occur in advanced MF. The successful procurement and analysis of atypical lymphocytes from hair-follicle epithelium by laser capture microscopy ushers in a new era in molecular diagnostics.  相似文献   
55.
OBJECTIVE: The objective of the present analysis is to examine lamotrigine (LTG) pharmacokinetics both during polytherapy with enzyme inducing antiepileptic drugs and to evaluate the time course of de-induction following the step-wise withdrawal of enzyme inducers. BACKGROUND: LTG pharmacokinetics can be significantly influenced by concomitant AEDs, and the addition of enzyme inducers can markedly increase LTG clearance, thereby reducing serum concentrations. A clinically relevant question is how will LTG clearance and resulting plasma concentrations be altered during concomitant enzyme inducer withdrawal/conversion process. DESIGN/METHOD: As part of a previously published, active-control, LTG monotherapy trial, dose and plasma concentration data for LTG, carbamazepine (CBZ) or phenytoin (PHT) were obtained. Following the attainment of a LTG target dose of 500 mg/day, CZB or PHT were withdrawn in weekly 20% decrements. Following inducer withdrawal, LTG was then continued as monotherapy for an additional 12 weeks. Plasma concentrations and daily doses of LTG, CBZ, or PHT were obtained at regularly scheduled study visits during inducer withdrawal and during LTG monotherapy. Pharmacokinetic analysis of the plasma concentration data was done to determine the time-course and effect of inducer plasma concentration on LTG oral clearance (Cl(o)), where LTG Cl(o) was estimated as the dose/concentration ratio. RESULTS: Of the 156 patients enrolled in this trial, 76 were assigned to LTG arm, 43 completed the withdrawal to monotherapy phase with 28 successfully completing the study. In a subset analysis of completers, LTG Cl(o) determined prior to withdrawal of the inducers was significantly greater in patients (n=28) on LTG+PHT (160% increase) than in those (n=48) receiving LTG+CBZ (62% increase): 1.77+/-0.77 vs. 1.06+/-0.41 ml/min/kg, respectively, p=0.017. The significant reduction in LTG Cl(o) occurred only when CBZ plasma concentrations reached approximately 2 microg/ml or PHT plasma concentrations reached zero. CONCLUSIONS: Mean LTG plasma concentrations will approximately double following the withdrawal PHT; however increases of only 60% may occur following the withdrawal of CBZ. Importantly, these data suggest that LTG concentrations would not be expected to increase until the concomitant inducer is almost completely removed.  相似文献   
56.
BACKGROUND: Anticonvulsant drugs have multiple mechanisms of action. Recent in vivo MRS studies suggest that cerebral gamma-aminobutyric acid (GABA) increases occur with the administration of certain anticonvulsants in humans. OBJECTIVE: To investigate the effect of topiramate, gabapentin, and lamotrigine on cerebral GABA concentrations in healthy volunteers and correlate the GABA concentrations with serum drug levels. METHODS: Seventeen healthy adults were randomly assigned to receive topiramate, gabapentin, and lamotrigine and underwent GABA measurements using a 4.1-T magnet from a 13.5-mL volume over the occipital region. GABA concentrations and serum levels were measured at 3 and 6 hours following administration of an acute single dose of one of the drugs. Thereafter, drugs were titrated over 4 weeks to target doses, with GABA measurements performed at 2 and 4 weeks. RESULTS: Cerebral GABA concentrations rose 70% in the acute phase compared with baseline for topiramate. GABA rose 48% at 6 hours with gabapentin but not with lamotrigine. With long-term dosing and once target doses were achieved at 4 weeks, significant elevations in GABA were observed compared with baseline for all three drugs (topiramate 46%, gabapentin 25%, lamotrigine 25%). CONCLUSION: This study demonstrates that single doses of topiramate and gabapentin increase cerebral GABA concentrations acutely (hours) in healthy individuals, but all drugs at clinically utilized doses increase cerebral GABA at 4 weeks. These results suggest that the mechanisms of action of anticonvulsant drugs are more complex and are likely to be multiple in nature.  相似文献   
57.
Rofecoxib, used for dysmenorrhea, caused a herpetiform fixed drug eruption predominantly involving the lips with classic clinical and histological findings in a red-brown lesion on the dorsal hand.  相似文献   
58.
Keratitis, ichthyosis, and deafness (KID) syndrome is a rare congenital disorder of unknown etiology in which increased susceptibility to viral, bacterial, and mycotic infections has been observed. We report an infant with KID syndrome who died from overwhelming systemic infection. To date, investigations into the immune function of patients with this syndrome have not revealed a common underlying systemic immune deficit. However, the severity of infections and multiplicity of organisms observed in this syndrome suggest that a primary immunodeficiency is present in addition to an impaired cutaneous barrier to microorganisms.  相似文献   
59.
PURPOSE: This study was conducted to examine the effect of oral creatine supplementation on the decline in peak isokinetic torque of the quadriceps muscle group during an endurance test. METHODS: Twenty-three active, but untrained, male subjects performed isokinetic strength tests on a Cybex II dynamometer at 180 degrees x s(-1). The protocol consisted of pre- and post-tests with five sets of 30 maximum volitional contractions with a 1-min rest period between sets. Subjects returned to perform the posttest after 5 d of placebo (4 x 6 g glucose x d(-1), N = 12) or creatine (4 x 5 g creatine + 1 g glucose x d(-1), N = 11) supplementation. Supplements and testing were administered in a double blind fashion. Peak torque was measured during each contraction and the 30 contractions were averaged for each set. RESULTS: A three-way mixed ANOVA with one between factor (placebo vs creatine) and two within factors (pre/post supplementation and sets 1-5) revealed no significant interactions, P > 0.05. The placebo vs creatine main effect was also nonsignificant, whereas the pre/post and set effects were significant (P < 0.05). Peak torque increased (approximately 3%) from pre- to post-testing, (P = 0.04), but the absolute magnitude of the differences is unlikely to be of any practical significance. Peak torque decreased from sets 1 to 4, whereas sets 4 and 5 were not different. A priori contrasts comparing the creatine group's performance pre vs post test for the fourth and fifth sets were nonsignificant (P > 0.05). CONCLUSIONS: Based on within and between group comparisons, we were unable to detect an ergogenic effect of oral creatine supplementation on the decline in peak torque during isokinetic exercise at 180 degrees x s(-1).  相似文献   
60.
The authors present 11 cases of idiopathic generalized epilepsy that began in adulthood at a mean age of 39 years. All patients had myoclonic jerks, five had absence seizures, and nine had infrequent generalized tonic-clonic seizures. A majority had a family history of seizures. EEG in all patients showed generalized epileptiform abnormalities, whereas neuroimaging and neurologic examination results were normal. This series appears to represent a previously undescribed idiopathic generalized epilepsy syndrome of adult myoclonic epilepsy.  相似文献   
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