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51.

Background

Weight gains in pregnancy within the recommended guidelines are associated with healthy fetal and maternal outcomes; higher weight gains are associated with fetal macrosomia. This study was a systemic review of randomized controlled trials on the effect of aerobic training on maternal weight in pregnancy.

Methods

The study data source was publications through May 2012 in the MEDLINE (PubMed) database. The citation lists of randomized controlled trials on the effect of aerobic training and maternal weight were extracted. Data on participants'' characteristics, study quality, population, intervention, treatment outcome (maternal weight gain) were collected and analyzed.

Results

There were 11 randomized controlled studies using body weight (kg) as measure of treatment outcome. A total of 1177 subjects were recruited in the 11 studies. The mean± SD weight gain (kg) for the exercise (11.31± 7.44kg) and control (14.42± 6.60kg) groups; Meta-analysis result indicated significant effect of aerobic training on maternal weight (t= -7.580, p= .000) at p< 0.05.

Conclusion

It was concluded that aerobic training is an effective tool in maternal weight gain control in pregnancy. More randomized controlled trials are warranted.  相似文献   
52.
53.
BACKGROUND: In cardiac transplant recipients, long-term survival may be limited by transplant coronary artery disease (TxCAD). Hyperhomocysteinemia (Hhcy) has been associated with vascular disease and is common in transplant recipients. The objective of this study was to determine the relationship between fasting homocysteine (Hcy) concentrations and TxCAD in a cohort of cardiac transplant recipients. METHODS: Forty-eight patients more than 5 yr after transplant were recruited from a cohort of 72 consecutive patients with in-depth analysis of homocysteine levels from the Cardiac Transplant Clinic. Early morning fasting blood was obtained, and the plasma separated and frozen within 30 min. Hcy concentrations were determined by high-performance liquid chromatography (HPLC) with pulsed integrated amperometry. Coronary angiograms were reviewed in a blinded fashion. TxCAD was diagnosed, using the most recent angiogram, when a >25% lesion was present anywhere in the coronary tree. RESULTS: Forty-eight patients transplanted between 1985 and 1994 were studied. The mean Hcy concentration for the cohort was 23.5+/-5.0 micromol/L, all patients had homocysteine levels above the upper range of normal (5-15 micromol/L). Hcy concentrations were significantly higher in patients with angiographic evidence of TxCAD: 25.0+/-5.9 vs. 21.9+/-3.4 micromol/L, p=0.03. This effect persisted when covariates were taken into account using logistic regression analysis. CONCLUSIONS: Hhcy is associated with TxCAD. Prospective studies are required to confirm this association and to assess the efficacy of Hcy-lowering therapy in this patient population.  相似文献   
54.
Abrahm  J; Besa  EC; Hyzinski  M; Finan  J; Nowell  P 《Blood》1986,67(5):1323-1327
Median survival is as little as 6 months for patients with refractory anemia with excess blasts who demonstrate an abnormal karyotype in the majority of marrow cells. We treated a patient who presented with 29% marrow blasts and 90% abnormal metaphases with 13-cis-retinoic acid. He achieved a complete clinical and cytogenetic remission during therapy. To determine the mechanism of the response, serial studies were done of the effects of 13-cis-retinoic acid and dexamethasone on in vitro growth of his marrow cells. During clinical remission, when the drug was not administered, marrow growth remained significantly depressed. During relapse, the remission growth pattern was replaced by overgrowth of the karyotypically abnormal monocytoid clone. Clonal growth occurred in cultures containing colony-stimulating activity or dexamethasone but was absent in cultures containing concentrations of 13-cis-retinoic acid achieved in vivo. After the drug was reinstituted, a second clinical stabilization developed. Since 13-cis-retinoic acid inhibits normal monocyte colony growth, we postulate that the patient's unusual clinical responses to the drug were due to in vivo growth inhibition of the malignant monocytoid clone.  相似文献   
55.
Knight  RD; Mangum  J; Lucas  DL; Cooney  DA; Khan  EC; Wright  DG 《Blood》1987,69(2):634-639
In previous studies of purine ribonucleotide metabolism in the human myeloid leukemia cell line HL-60, we observed that there is a down- regulation of guanine ribonucleotide biosynthesis from the central intermediate, inosine monophosphate (IMP) and a depletion of intracellular guanosine triphosphate (GTP) and guanosine diphosphate (GDP) pools that occur during the induced maturation of these cells. We also found that inhibitors of IMP dehydrogenase, the enzyme that catalyzes the first step of guanylate synthesis from IMP, are potent inducers of HL-60 maturation. Because of these observations we specifically investigated the activity of IMP dehydrogenase in HL-60 cells and in a new inducible human myeloid leukemia cell line, RDFD2- 25, both during maintenance culture and during induced maturation of the cells. Enzyme activity was examined directly in cell extracts with a radiometric assay that measures free 3H2O formed from [2-3H] IMP during the conversion of IMP to XMP. Uninduced HL-60 and RDFD2 cells in maintenance culture were found to have high levels of IMPD activity (5.2 to 5.7 pmol IMP metabolized/10(7) cells/min) compared with normal neutrophils and monocytes that had been purified from blood (less than 1.5 pmol IMP metabolized/10(7) cells/min). However, when HL-60 and RDFD2-25 cells were induced to mature with retinoic acid (10(-6) mol/L), dimethylformamide (6 X 10(-2) mol/L), or a known IMPD inhibitor, tiazofurin (10(-6) mol/L), IMPD activity in the cells fell by 51% to 80% within three to six hours. These changes in IMPD activity preceded detectable functional and antigenic maturation of the cells by at least 12 hours and were not temporally related to changes in cellular proliferation. These findings are consistent with the concept that the regulation of myeloid cell maturation may be influenced by intracellular concentrations of guanine ribonucleotides because IMP dehydrogenase activity is known to be rate limiting for the production of these nucleotides.  相似文献   
56.
EC Vamvakas 《Transfusion》1995,35(9):760-768
BACKGROUND: Meta-analysis was used to explain disagreements across observational studies in regard to the association between perioperative transfusion and cancer recurrence. STUDY DESIGN AND METHODS: Observational studies published in English from 1982 through 1994 were retrieved. Five or more articles published in complete form were identified for each of six cancer sites: colorectum, breast, head and neck, lung, prostate, and stomach. Necessary information for building a 2 × 2 contingency table could be extracted from 60 studies. Summary relative risks (RR) reflecting the "average" adverse transfusion effect were computed for each cancer site by the random- effects method. Seven study characteristics were examined as potential explanations for the disagreements among the published studies. RESULTS: Before any adjustment for the effect of confounding, computed crude summary RRs suggested a significant (p < 0.05) deleterious transfusion effect in all cancer sites, except for breast. The RR of an adverse outcome was 1.49 in colorectal cancer (95% CI, 1.23-1.79) and ranged from 1.06 in breast cancers to 3.62 in head and neck cancers. The disagreements among published studies were most marked in the case of colorectal and gastric cancers. These discrepancies could be explained, in part, by study design, because prospective investigations had not produced a significant unadjusted transfusion effect (RR = 1.18; 95% CI, 0.93-1.51 in the case of colorectal cancer). CONCLUSION: A reduction in the size of the computed unadjusted transfusion effect (of an appropriate magnitude to adjust for the effect of confounding) might eliminate the significance of the average adverse effect in most studied cancer sites. Whether the entire unadjusted transfusion effect should be ascribed to the effect of confounding or whether a true, deleterious transfusion effect also exists can be resolved only by randomized controlled trials.  相似文献   
57.
鉴定γB-晶体蛋白非酶糖基化位点。方法用离子交换HPLC纯化小牛晶状体γB-晶体蛋白,与果糖保温后用糜蛋白酶水解。糖基化的肽用Affi-Gel601柱层析纯化,并用RP-HPLC分离各肽。  相似文献   
58.
There is evidence that endogenous opioid peptides exert an inhibitory effect on pituitary luteinizing hormone (LH) secretion both in animals and in humans, by interacting with mu-opioid receptors. However, a role for delta-opioid receptors in the regulation of gonadotrophin releasing hormone (GnRH) secretion has recently been suggested. In the present study, we evaluated the effect of the highly selective delta-opioid receptor agonist deltorphin on the LH and follicle stimulating hormone (FSH) responses to naloxone in six healthy fertile women during the luteal phase of the menstrual cycle. Deltorphin infusion alone (7 microg/kg/min for 60 min) did not significantly change the basal serum concentrations of LH in this group of women. The intravenous (i.v.) bolus administration of naloxone (15 mg) induced a significant (P < 0.001) increase in serum LH concentrations (from a mean basal value of 4.24+/-1.10 IU/l to a peak of 13.27+/-1.8 IU/l). The LH response to naloxone was significantly (P < 0.001) blunted by preinfusion of deltorphin (13.27+/- 1.80 IU/l versus 4.80+/-1.18 IU/l). No significant changes in FSH concentrations were observed during deltorphin, naloxone or deltorphin plus naloxone administration. These data indicate that activation of delta-opioid receptors can reduce naloxone-induced LH release, suggesting a possible role of delta receptors in opioidergic modulation of LH secretion in women.   相似文献   
59.
BACKGROUND: Human red cells containing inositol hexaphosphate (IHP) have a lowered O2 affinity, though they are able to bind and carry about the same amount of oxygen as native cells. These modified cells therefore deliver oxygen more efficiently to the tissues, which is a property of potential clinical utility. Investigators set out to devise a system and procedure by which large volumes of IHP-containing red cells, suitable for transfusion, could be produced quickly and efficiently. STUDY DESIGN AND METHODS: The encapsulation of IHP into human red cells by use of several variations of static electroporation was performed to define the conditions necessary for optimal IHP incorporation and cell survival. These conditions were used as a starting point for optimization of a flow electroporation system. RESULTS: When fresh human red cells in a 35 mM IHP solution are subjected to three exponential pulses of field strength of 2.98 +/− 0.064 kV per cm per pulse and pulse length of 2.0 +/− 0.2 msec per pulse while flowing through a cooled electroporation chamber, the condition of the resultant cells, according to the criteria used here, is optimized. After storage for 24 hours in plasma at 37 degrees C, the cells show more than 85-percent survival (in vitro) and hematologic indices nearly identical to those of unpulsed control cells. The p50 value of these cells, however, has doubled to 50.4 +/− 2.0 torr. The processing time for 1 unit of blood is 90 minutes. CONCLUSION: These data indicate that the system described here can efficiently produce low-oxygen-affinity red cells in volumes that are useful in clinical applications.  相似文献   
60.
Abnormal fetal and infant growth have increasingly been correlated with adult onset cardiovascular disease. To date, there is little known about the lipid fatty acid profiles in infant cardiovascular tissue. Therefore, we analysed total lipid fatty acids from thoracic and abdominal aorta intima and media from 24 normally grown sudden infant death syndrome cases. Aorta from small for gestational age (n = 2), failure to thrive from birth (n = 3), and premature (n = 1) infants were also examined. Dihomo-gamma-linolenic acid (C20:3n-6) and oleic acid (C18:1n-9) concentrations were significantly lower in the thoracic than in the abdominal aorta. Similar dietary related differences were found in the subgroup (n = 15) of infants fed on formula milks. Both abdominal and thoracic intimal arachidonic (C20:4n-6) to dihomo-gamma-linolenic acid ratios were greater in the infants with retarded growth after birth than in their normally grown counterparts. Growth restriction in infancy might disrupt the normal accretion of vascular endothelial polyunsaturated fatty acids.  相似文献   
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