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1.
创伤病人的手术与焦虑状态调查   总被引:6,自引:0,他引:6  
采用状态——特质焦虑问卷及10项躯体性焦虑测试题,对40例外科创伤病人手术前后的焦虑状态调查显示:术前状态焦虑量表评分显著高于术后;术前躯体性焦虑评分显著高于术后;高特质焦虑评分亚组与低特质焦虑评分亚组术前状态焦虑评分无显著差异,但术后则前者显著高于后者;急诊手术者手术前后状态焦虑评分显著高于择期手术者。  相似文献   
2.
X-linked sideroblastic anemia and ataxia (XLSA/A) is a recessive disorder characterized by an infantile to early childhood onset of non-progressive cerebellar ataxia and mild anemia with hypochromia and microcytosis. A gene encoding an ATP-binding cassette (ABC) transporter was mapped to Xq13, a region previously shown by linkage analysis to harbor the XLSA/A gene. This gene, ABC7, is an ortholog of the yeast ATM1 gene whose product localizes to the mitochondrial inner membrane and is involved in iron homeostasis. The full-length ABC7 cDNA was cloned and the entire coding region screened for mutations in a kindred in which five male members manifested XLSA/A. An I400M variant was identified in a predicted transmembrane segment of the ABC7 gene in patients with XLSA/A. The mutation was shown to segregate with the disease in the family and was not detected in at least 600 chromosomes of general population controls. Introduction of the corresponding mutation into the Saccharomyces cerevisiae ATM1 gene resulted in a partial loss of function of the yeast Atm1 protein. In addition, the human wild-type ABC7 protein was able to complement ATM1 deletion in yeast. These data indicate that ABC7 is the causal gene of XLSA/A and that XLSA/A is a mitochondrial disease caused by a mutation in the nuclear genome.  相似文献   
3.
Glycol ethers such as ethylene glycol monomethyl ether (EGME)are common solvents used in many industrial products. A largenumber of individuals are exposed to EGME through differentexposure routes. We investigated the differential distributionof EGME following various routes of administration using wholebody autoradiographic (WBA) techniques. Male B6C3F1 mice weretreated with tracer iv or oral doses of [2-14C]EGME.(4.05 µgEGME/kg equivalent to 0.8 mCi/kg) and euthanized at 1 and 24hr following treatment. In both groups of animals the highestlevels of radioactivity were detected in the liver, urinarybladder, bone marrow, kidney, and epididymis, at 1- and 24-hrtime periods. Computer-assisted quantitation of WBA indicatedthat there was markedly higher deposition of [2-14 and/or itsmetabolites in various tissues of the orally treated animalsthan in animals treated intravenously. Our studies also suggestthat [2-14C]EGME is rapidly distributed either from blood orstomach to various tissues. Preferential deposition of radioactivityin the peripheral tissues of the bone, with a progressive inwardaccumulation in the bone marrow, was observed. Selective permeabilityof EGME and/or its metabolites was indicated by the higher uptakeby the epididymis than that by testis. The high levels of radioactivityin biosynthetically active tissues, e.g., the liver, bone marrow,and gastric mucosa, is an indication of persistent interactionof the compound with cellular components of these tissues. Theseinteractions may lead to EGME toxicity.  相似文献   
4.
Cerebral amyloid angiopathy (CAA) is conspicuous for its association with Alzheimer disease (AD) and as a cause of lobar hemorrhages in the elderly, but its role in cerebral infarction is less clear. There is evidence that CAA may also be a risk factor for ischemic infarction in AD. To further investigate CAA as a risk factor for infarction, we studied 108 cases of recent cerebral or cerebellar infarction diagnosed in tissue samples obtained from surgical material. There were 69 males and 39 females with a mean age of 52 yr (range 1-86). The majority of biopsies were obtained from the frontal and parietal lobes. Radiological studies demonstrated a lesion confined to a vascular distribution in 12 of the 17 (71%) cases examined. Microscopic sections stained with hematoxylin and eosin revealed complete, organizing infarction in 107 cases with areas of coagulative necrosis, anoxic-ischemic neuronal injury, inflammation, macrophages, vascular proliferation, gliosis, and swollen axons. One case showed an incomplete infarct. Most cases also exhibited a minor hemorrhagic component with hemosiderin and hematoidin pigments. CAA, defined as amyloid deposition in the walls of leptomeningeal and parenchymal arteries, was found by immunohistochemical stains for beta amyloid in 14 (13%) cases of complete cerebral infarct. Cortical beta amyloid plaques were found by immunohistochemistry in 19 (17%) cases. Cerebral or cerebellar tissues containing cortex and leptomeninges obtained from 136 patients with a mean age of 52 yr (range 1-85) during surgical procedures for diagnosis of primary or metastatic neoplasms and demyelinating lesions were used as age-matched controls. In this control group, CAA was found in 5 (3.7%) and beta amyloid plaques in 19 (14%). The results indicate that CAA, but not beta amyloid plaque formation, is significantly more common in patients with ischemic cerebral infarction than in age-matched controls with nonvascular lesions (odds ratio 3.8; 95% confidence interval 1.3-10.9; p < 0.01). Our results indicate that CAA is a risk factor for ischemic cerebral infarction in the population studied.  相似文献   
5.
Malignancy-associated hypercalcemia is a common and recalcitrant problem. Current modes of therapy are often ineffective or prohibitively toxic. Clodronate disodium is a diphosphonate capable of inhibiting bone resorption resulting in a hypocalcemic effect. In this randomized, placebo-controlled study, we investigated the effect of hydration only (Rx-1) vs the effect of hydration plus either intravenously administered clodronate disodium, 4 mg/kg of body weight per day for three days (Rx-2) or intravenously administered clodronate disodium, 12 mg/kg of body weight given once only (Rx-3). By the third day of observation, Rx-2 produced a significant 2.8 mg/dL (0.70 mmol/L) reduction in serum calcium levels, whereas Rx-1 and Rx-3 did not produce a significant hypocalcemic effect when compared with baseline values. There were no toxicities observed. Intravenously administered clodronate appears to be an excellent agent for the acute treatment of malignancy-associated hypercalcemia.  相似文献   
6.
Background: It has been shown that prolonged daily peroral magnesium (Mg) administration, as tabs of Mg(OH)(2), used as the only treatment in postmenopausal osteoporosis, causes a significant increase in BMD. Objective: In order to obtain definitive evidence of causality of magnesium deficiency in the etiology of osteoporosis, we spent 1 year examining rats given a daily Mg-deficient diet (200 ppm) and compared them with rats given a Mg-adequate diet (2000 ppm). Methods: Sixteen female Sprague-Dawley rats, mean weight 110 (S.D. 23) g, were divided into two groups and randomly assigned to a semisynthetic diet that differed only in Mg content. Urine samples were collected every 3 months and blood was collected at the end of the trial. After the animals were sacrificed, the L3-L5 vertebrae and the femoral regions were examined for bone density (BMD) using dual energy X-ray absorptiometry. The femoral bones were examined for bone fragility and the tibiae by histomorphometry, and the mineral content of the bones was estimated. Results: The mean BMD of L3-L5 vertebral bone was significantly higher in group A (adequately nourished) than in the Mg-deficient group B (p=0.035, one-tail); in addition, the BMD of the femural region was significantly higher in group A (p=0.045, one-tail). The bending stiffness of the femur was slightly higher in group A than in group B; however, after correction to diminish the influence of the difference in bone dimensions between the two groups, femur rigidity (i.e., the loss of elasticity) in group B became significantly higher than that in group A (p=0.024). The force needed to break the bone was significantly higher in group A than in group B (p=0.024) and it remained higher after correction, although no longer significantly. In group B, the diminution of the trabecular bone volume, in relation to tissue volume (BV/TV), and the increase in the degree of trabecular interconnection (TBPf) clearly showed the presence of osteoporosis. On microscopy, focal osteoporosis of the metaphyseal spongious bone was observed in the bone rendered Mg-deficient. Conclusions: Because osteoporosis is characterized by lowering of BMD, increased bone fragility, and altered bone architecture, our study showed that maintaining rats for 1 year on a Mg-deficient diet gives rise to the appearance of osteoporosis.  相似文献   
7.
8.
A high prevalence of the sequence variant c.1436C→T in the CPT1A gene has been identified among Alaska Native newborns but the clinical implications of this variant are unknown. We conducted medically supervised fasts in 5 children homozygous for the c.1436C→T variant. Plasma free fatty acids increased normally in these children but their long-chain acylcarnitine and ketone production was significantly blunted. The fast was terminated early in two subjects due to symptoms of hypoglycemia. Homozygosity for the c.1436C→T sequence variant of CPT1A impairs fasting ketogenesis, and can cause hypoketotic hypoglycemia in young children.Trial registrationwww.clinical trials.gov NCT00653666 “Metabolic Consequences of CPT1A Deficiency”  相似文献   
9.
A toxoid vaccine, composed of purified pertussis toxin inactivated with H2O2 (NICHD-Ptxd), was developed on the basis of evidence that serum neutralizing antibodies (antitoxin) would confer immunity to pertussis. In vivo and in vitro assays of NICHD-Ptxd showed only trace or nondetectable levels of pyrogenic, adenosine diphosphate-ribosyltransferase, binding and pharmacologic activities. Nevertheless, about 40% of the antigenicity of pertussis toxin was retained. Adult volunteers were injected, two times 6 weeks apart, with either 10 (n = 21), 50 (n = 25), or 75 (n = 30) micrograms/dose of one lot, Ptx-06, adsorbed onto AI(OH)3. Neither fever nor changes in the levels of leukocytes, lymphocytes, fasting blood glucose, or insulin were observed in the volunteers. The optimal immunizing dose, 50 micrograms, induced levels of antitoxin (geometric mean (GM) 302 U) comparable to those found in eight adults convalescent from pertussis (GM 269 U) and greater than those found in 18-month-old children after their fourth dose of diphtheria and tetanus toxoids and pertussis vaccine (GM 20.0 U, p less than 0.001). These data indicate that NICHD-Ptxd is safe and immunogenic in adults, and they justify its evaluation in infants and children.  相似文献   
10.
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