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251.
252.
ObjectiveTo compare clinical outcomes of 3 treatment regimens—glucocorticoids (GCs), oral contraceptives (OCs), or a combination of both—administered to adolescents and young women diagnosed in childhood with nonclassical congenital adrenal hyperplasia (NCCAH), who had been treated with GCs until their adult height was achieved.MethodsA retrospective study of medical records of 53 female patients with NCCAH followed in 3 tertiary pediatric endocrinology institutes. The 3 treatment groups were compared for the prevalence of hirsutism and acne, standardized body mass index (BMI)-standard deviation score (SDS), and androgen levels at the attainment of adult height (baseline), 1-year later, and at the last documented visit.ResultsAt baseline, there were no significant differences among groups in BMI-SDS, androgen levels, hirsutism prevalence, acne, or irregular menses. From baseline to the last visit, the rate of hirsutism declined significantly only in the OC group (37.5% vs 6.2%, respectively; P = .03). The rate of acne declined in the combined group (50% vs 9%, respectively; P = .03) with a similar tendency in the OC group (50% vs 12.5%, respectively; P = .05). No significant changes were observed in BMI-SDS for the entire cohort or any subgroup during follow-up. A significant rise in androstenedione (P < .001), testosterone (P < .01), and 17-hydroxyprogesterone (P < .01) levels was observed only in the OC group.ConclusionIn girls diagnosed in childhood with NCCAH, who require treatment for hyperandrogenism following completion of linear growth, management should be tailored individually using a patient-centered approach. Treatment with OCs might be better than that with GCs for regression of hirsutism and acne. The long-term effects of elevated levels of androgens associated with this treatment regimen should be further studied.  相似文献   
253.
Cardiac myxomas are rare tumors that may be encountered sporadically or in the context of the Carney complex. The molecular basis for the development of cardiac myxomas and Carney complex tumors is unclear. Pathological myocardial function and myocardial hypertrophy have been associated with alterations in the heterotrimeric GTP-binding proteins. The postulated proto-oncogenic character of the gene encoding the alpha subunit of the stimulatory GTP-binding protein Gsα (gsp) in pituitary and thyroid tumors, the finding of identical somatic gsp mutations in the myocardium of patients with McCune-Albright syndrome, and the associated endocrine anomalies of the Carney complex prompted us to investigate the occurrence of activating missense mutations in the Gsα gene in 10 sporadically occurring atrial myxomas and in 8 tumors from 7 patients with Carney complex. No gsp mutations could be demonstrated by using the polymerase chain reaction and denaturing gradient gel electrophoresis complemented by direct DNA sequencing. Thus, activating Gsα mutations neither are associated with the development of atrial myxomas, nor can be demonstrated in other tumors from patients with Carney complex. The significance of these mutations in the myocardium of asymptomatic patients with McCune-Albright syndrome remains to be determined. Received: 7 March 1996 / Revised: 10 April 1996  相似文献   
254.
The effect of DL-propranolol on 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine-induced experimental porphyria was studied.dl-Propranolol, a beta-adrenergic blocking agent with non-specific membrane effects, partially inhibited 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine-induced delta-aminolevulinate synthetase activity both in rats and in chick embryo liver cells in culture.In rats, DL-propranolol decreased urinary delta-aminolevulinate and porphobilinogen but no change occurred in the 24-h urinary excretion of total porphyrins and in the concentration of porphyrins in the liver. In cultured chick embryo liver cells treated with 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine, DL-propranolol decreased accumulation of porphyrins in the medium.d-Propranolol, oxprenolol and quinidine acted like dl-propranolol in chick embryo liver cells in culture treated with 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine. Pindolol, practolol and lidocaine had no effect.Phenobarbitone had a synergistic effect on the induction of delta-aminolevulinate synthetase by 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine in cultures of chick embryo liver cells. This induction was partially inhibited by propranolol. However, the increased accumulation of porphyrins in the medium caused by 3′,5′-diethoxycarbonyl-1,4-dihydrocollidine was inhibited by the addition of phenobarbitone. This inhibited induction was further decreased by propranolol.Most of our results indicate that the drugs tested act mainly by their effects on membranes.  相似文献   
255.
ObjectiveAnemia is a known complication of diabetes mellitus (DM); however, its prevalence and prognostic relevance in patients with DM and pre-DM with normal kidney function have not been well defined. This study assessed the prevalence of anemia in patients with DM and pre-DM and evaluated its association with clinical outcomes during a 4-year follow-up period.MethodsThis retrospective analysis included patients with DM and pre-DM referred to the Meir Medical Center Endocrine Institute in 2015. Patients with an estimated glomerular filtration rate (eGFR) of <60 mL/min or any other recognized cause of anemia were excluded. The risk of developing microvascular or macrovascular complications or of death during the 4-year follow-up period was determined.ResultsA total of 622 patients (408 with DM and 214 with pre-DM) were included. The mean age of the patients was 64 ± 10.6 years, and 70% were women. The baseline hemoglobin A1C level was 7.1% ± 1.7% (54 mmol/mol), and the eGFR was 86.1 ± 15.3 mL/min. At the time of inclusion, 77 patients (19%) with DM and 23 (11%) with pre-DM had anemia (hemoglobin level 11.9 ± 0.8 and 11.8 ± 0.8 g/dL, respectively), compared with normal hemoglobin levels of 13.8 ± 0.9 and 13.7± 0.9 g/dL, respectively, in the others. A multivariable analysis demonstrated an inverse correlation between baseline hemoglobin (as a continuous variable) and mortality (P = .035), microvascular complications (P = .003), and eGFR decline (P < .001) but not between baseline hemoglobin and macrovascular complications (P = .567).ConclusionThis study found a significant prevalence of anemia unrelated to renal failure, both in patients with DM and pre-DM. Anemia in these patients is associated with the development of microvascular complications, eGFR decline, and mortality. These results underscore the need for intensive lifestyle and pharmacologic interventions in these patients.  相似文献   
256.
Neurite outgrowth and branching patterns are instrumental in dictating the wiring diagram of developing neuronal networks. We study the self‐organization of single cultured neurons into complex networks focusing on factors governing the branching of a neurite into its daughter branches. Neurite branching angles of insect ganglion neurons in vitro were comparatively measured in two neuronal categories: neurons in dense cultures that bifurcated under the presence of extrinsic (cellular environment) cues versus neurons in practical isolation that developed their neurites following predominantly intrinsic cues. Our experimental results were complemented by theoretical modeling and computer simulations. A preferred regime of branching angles was found in isolated neurons. A model based on biophysical constraints predicted a preferred bifurcation angle that was consistent with this range shown by our real neurons. In order to examine the origin of the preferred regime of angles we constructed simulations of neurite outgrowth in a developing network and compared the simulated developing neurons with our experimental results. We tested cost functions for neuronal growth that would be optimized at a specific regime of angles. Our results suggest two phases in the process of neuronal development. In the first, reflected by our isolated neurons, neurons are tuned to make first contact with a target cell as soon as possible, to minimize the time of growth. After contact is made, that is, after neuronal interconnections are formed, a second branching strategy is adopted, favoring higher efficiency in neurite length and volume. The two‐phase development theory is discussed in relation to previous results. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2005  相似文献   
257.
The predisposing genetic defect in multiple endocrine neoplasia type 1 has been assigned to chromosomal region 11q13. Our previous attempts to identify the MEN1 gene have resulted in the isolation of the phospholipase Cβ3 gene from the actual region. PLCB3 plays an important role in signal transduction and, moreover, shows loss of expression in some endocrine tumors, in accordance with a putative tumor suppressor gene function, and thus appears to be an excellent candidate for MEN1. We have therefore undertaken screening for constitutional mutations in individuals from MEN1 families. Several sequence alterations have been discovered, none of them however fulfilling the criteria for a disease-related mutation. We can now exclude PLCB3 from candidacy as the MEN1 gene. Received: 24 July 1996 / Revised: 16 August 1996  相似文献   
258.
Acute liver failure in infancy accompanied by lactic acidemia was previously shown to result from mtDNA depletion. We report on 13 unrelated infants who presented with acute liver failure and lactic acidemia with normal mtDNA content. Four died during the acute episodes, and the survivors never had a recurrence. The longest follow-up period was 14 years. Using homozygosity mapping, we identified mutations in the TRMU gene, which encodes a mitochondria-specific tRNA-modifying enzyme, tRNA 5-methylaminomethyl-2-thiouridylate methyltransferase. Accordingly, the 2-thiouridylation levels of the mitochondrial tRNAs were markedly reduced. Given that sulfur is a TRMU substrate and its availability is limited during the neonatal period, we propose that there is a window of time whereby patients with TRMU mutations are at increased risk of developing liver failure.  相似文献   
259.
Abstract. Pieces cut from colonies of the soft coral Dendronephthya hemprichi exhibited rapid and effective attachment to hard surfaces. Attachment involved development of root-like processes (RLPs), which appeared at the basal part of the fragment 4 days after its removal from the colony. The fine structural changes and cascade of cellular events occurring in the RLP before and after attachment were studied using SEM, TEM, and LM. The epidermis of the RLPs is actively involved in the attachment process and several distinct phases are documented: appearance of numerous oval vesicles, extrusion of these vesicles resulting in the formation of an outer layer composed of extracellular organic matrix and organellar debris, which functions as an adhesive device leading to initial attachment. The latter phase was followed by the formation of desmocytes, which develop in the RLP epidermis and function as anchoring devices, mediating the firm attachment of the fragment to the substrate. This is the first evidence among anthozoans that desmocytes play an active role in anchoring tissue to substrate and thus extends the range of functions exhibited by desmocytes among anthozoans.  相似文献   
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