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The effect of dietary manipulation on global tooth uptake of 47Ca-chloride was evaluated in three rat models of metabolic bone diseases verified by histologic bone study. The 24-hr tooth uptake of 47Ca-chloride was significantly decreased in the osteomalacic group, and was increased in the osteoporotic group at the fourth week. Tooth uptake closely paralleled femoral uptake at a correlation coefficient of 0.73 (p less than 0.01). The uptake of 47Ca-chloride in tooth was found to be more affected by dietary manipulation than that in femur in our rat models.  相似文献   
3.
We measured serum thymidine kinase (TK) activity with a radioenzyme assay system employing [I-125]-iododeoxyuridine as the tracer on serial specimens from five bone marrow transplant (BMT) patients before and after transplantation. The serum level of TK activity in the 4 patients with effective BMT treatment ranged from 3.0 to 16.9 U/L (mean, 7.80 U/L) before transplantation and from 27.3 to 236.1 U/L (mean, 82.95 U/L) after the BMT treatment. Mean serum TK activity increased 13.17-fold (range, 1.68 to 29.14-fold). In contrast, the activity in the patient with ineffective BMT treatment was not significantly different during, before, or after BMT treatment. In addition, serum TK activity in BMT patients was well correlated with the change in the number of leukocytes before and after BMT treatment [r = +0.709 (p less than 0.01), y = 0.012 x +0.87]. We conclude that the determination of serum TK activity in BMT patients is very useful in monitoring the course of bone marrow transplantation in the early recovery phase.  相似文献   
4.
A cerebral type of Lewy body disease (LBD) is proposed. Lewy body disease was split formerly into three types: brainstem type, transitional type and diffuse type. The diffuse type is now called diffuse Lewy body disease (DLBD). These three types are characterized pathologically by the presence of a large number of Lewy bodies in the CNS. In the brainstem type, Lewy bodies are numerous in the brainstem and diencephalon nuclei, and in DLBD, a vast number are present not only in these nuclei but also in the cerebral cortex and amygdala. In the cerebral type of LBD, as many Lewy bodies are found in the cerebral cortex and in the amygdala as there are in DLBD, but only rarely are they present in the brainstem and diencephalon nuclei. Thus, this type of LBD is different from other types in that it has no parkinson pathology. Therefore, parkinsonism fails to occur throughout the whole clinical course of this disease. The existence of a cerebral type of LBD suggests that Lewy bodies occur in the cerebral cortex earlier than in the brainstem nuclei and that cortical Lewy bodies appear even when the mesocortical dopaminergic system is intact. In addition, this might explain why dementia frequently precedes parkinsonism in DLBD.  相似文献   
5.
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing.  相似文献   
6.
The aim of the present study was to investigate the roles of tyrosine kinase (TK) in the insulin action on cell volume in fetal rat (20-day gestational age) type II pneumocyte. Insulin (100 nmol/l) increased cell volume, and this insulin (100 nmol/l) action was completely blocked by 50 μmol/l bumetanide (BMT) and 10 μmol/l amiloride (AML). This observation indicates that 100 nmol/l insulin activates BMT-sensitive Na+/K+/2Cl? cotransporter and AML-sensitive pathways. The stimulatory action of 100 nmol/l insulin on BMT-sensitive Na+/K+/2Cl? cotransporter was completely abolished by 10 μmol/l lavendustin A (LAV-A, an inhibitor of TK), however 100 nmol/l insulin could stimulate AML-sensitive pathways even in LAV-A (10 μmol/l)-treated cells. These observations indicate that the insulin (100 nmol/l) action on the BMT-sensitive Na+/K+/2Cl? cotransporter is mediated through TK-dependent pathways, while 100 nmol/l insulin requires a TK-independent pathway to show the stimulatory action on the AML-sensitive pathways. From these observations we conclude that TK-dependent and -independent pathways are involved in the insulin (100 nmol/l) signaling in fetal rat type II pneumocyte.  相似文献   
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8.
Effects of cefminox (CMNX) on hemostasis and blood coagulation system were studied. Adult in-patients admitted to 237 centers (310 clinics) nationwide in Japan during the period from April 1988 to March 1989 were followed up using a newly designed uniformed protocol. Case cards recovered were inspected by an evaluation committee and patients to be included in analysis were determined according to the protocol. Presence or absence of abnormalities in the hemostasis and blood coagulation system was examined objectively using criteria for evaluation prepared by the committee. Out of 1,374 patients included in analysis, 10 patients were judged as having abnormalities which were suspected to have causal relationships with CMNX. Prolongation in prothrombin time was observed in 4 cases (0.29%), prolongation in activated partial thromboplastin time in 4 cases (0.29%), and decrease in fibrinogen in 2 cases (0.15%). Decrease in platelet count was not detected in any of the cases. Cross-sectional analysis according to background factors in these 10 cases revealed that abnormalities of the hemostasis and blood coagulation systems were significantly higher (P less than 0.01) for the group positive for underlying disease or complications ("positive" group) than the "negative" group. Five out of 9 patients of the positive group had malignant neoplasm. Other than this factor, no items showed statistically significant differences. From these results it is considered that the administration of CMNX is nearly free of effects on the hemostasis and blood coagulation system and development of laboratory abnormalities is chiefly due to the patients' condition.  相似文献   
9.
Diminution of contractile response of the aorta from endotoxin-injected rats   总被引:13,自引:0,他引:13  
The contractility of a helical strip of the thoracic aorta was studied in rats injected intraperitoneally with endotoxin. The contractile response to any of the agonistic agents, KCl, norepinephrine or 5-hydroxytryptamine was time dependently diminished in the endotoxin-injected rats compared to the controls. This diminution preceded the depression of blood pressure. When the external calcium concentration was increased from 2.5 to 7.5 mM after the KCl (80 mM)-induced contractile response reached a plateau, the diminished contractile response was reversed in the endotoxin-injected group. The strips from the endotoxin-injected rats showed a higher 45CaCl2 uptake into the vascular tissue with the KCl-stimulated contraction. These findings suggest that the blood pressure depression during endotoxic shock may be attributed partially to the diminished contractility of the blood vessels and that this diminution is induced by a disorder of calcium utilization within vascular smooth muscle during vascular contraction.  相似文献   
10.
Rats were maintained on liquid diets containing ethanol (35% of total calories) or an equicaloric volume of sucrose instead of ethanol for 10 wk. Vascular strips of isolated rat aortas were mounted in organ chambers to record isometric tension. Ethanol in vitro inhibited the endothelium-dependent relaxation responses to acetylcholine and ATP in both pair-fed control and ethanol-fed rats. The inhibitory effect of ethanol was greater in the pair-fed rats. In addition, the magnitudes of these relaxation responses in the absence of ethanol in vitro in pair-fed rats were similar to those in the presence of ethanol in ethanol-fed rats. In the absence of ethanol in vitro, the relaxations in response to acetylcholine and ATP in the ethanol-fed rats were greater than in the pair-fed rats. These results suggest that chronic ethanol consumption can induce tolerance to ethanol-induced inhibition of endothelium-dependent relaxation responses to acetylcholine and ATP, and that the relaxations can become adapted to the presence of plasma levels of ethanol, which may inhibit the relaxation in vivo. The augmented relaxation in the ethanol-fed rats may result from the mechanism causing tolerance to the inhibitory effect of ethanol.  相似文献   
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