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The standard technique for Norplant implants removal was compared with a new technique called the “U” technique, which employs the use of a modified no-scalpel vas deferens holding forceps to grasp and remove the capsules. Seventy-six women requesting Norplant implants removal were randomly assigned to Group 1 (standard removal technique) or Group 2 (“U” removal technique). Variables measured included: (a) time required for complete removal, (b) number of capsules not broken or damaged during removal, and (c) number of incisions required for removal of all six capsules. In clients with visible or palpable capsules, the standard removal technique required significantly more time to remove all six capsules, on average, than the “U” technique (19 versus 7 minutes, p < 0.001); also more capsules were damaged during removal (5.6 undamaged versus 6.0,p < 0.01). In addition, with the standard technique, five clients required two incisions for removal of all six capsules while none of the clients required more than one incision with the “U” technique. Our conclusion is that the “U” technique is a quicker and easier method of removing Norplant capsules than the standard technique.  相似文献   
23.
A study of trace element levels in hair was performed on 183 eight-year-old schoolchildren living in Bijlmermeer, a suburb of Amsterdam, the Netherlands. Microlevel-elements, such as Au, Co, Ag, Se and Cd, and macrolevel-elements, such as Pb, Cu, Fe and Zn, were analyzed using the NAA and AAS methods. The total group of children was divided into subgroups, according to ethnic origins: Caucasian boys and girls, Hindustani children and a Surinamese rest group. The relation between element levels in hair and nutritional status, anthropometric and haematological variables were studied. Most levels corresponded reasonably with literature data. The iron in hair may be positively related to daily dietary intake of iron.  相似文献   
24.
Information about trace metals and coronary heart disease risk indicators was collected in 1977 among 152 men aged 57-76 years in the town of Zutphen, the Netherlands. Serum zinc, serum copper, blood cadmium, and blood lead were determined by atomic absorption spectrometry and serum lithium by flame emission spectrometry. After uni- and multivariate regression analysis, the following statistically significant relations were found: serum zinc was inversely related to resting heart rate; serum copper was positively related to cigarette smoking and inversely to high density lipoprotein cholesterol; blood cadmium was strongly positively related to cigarette smoking and inversely to Quetelet index; the positive relation between blood lead and cigarette smoking was of borderline significance; and blood lead was related to blood pressure, with the relation being stronger for systolic than for diastolic blood pressure.  相似文献   
25.
Summary A study has been performed in 148 non occupationally exposed subjects (19–21 yrs) divided into three groups: males, females without and females using oral contraceptives. PbB-levels ranged from 46 to 238 ppb. Freeerythrocyte-porphyrins (FEP), serum iron (Fe-S), Hb, Ht, total iron-bindingcapacity and unsaturated-iron-binding-capacity were measured. A negative correlation was found between PbB and Fe-S in males only. In females FEP was higher than in males at same PbB-levels. Females using oral contraceptives had higher Fe-S-levels and total-iron-binding-capacity than females not taking these; no difference was found between individual preparations. Two hypotheses are suggested to explain the negative relationship between lead in blood and serum iron in males. In a study of 51 other male subjects, 19-21 yrs, again a negative trend for Fe-S with increasing PbB was observed; the pooled data showed a negative relation; there was no difference in morning and afternoon Fe-S levels.  相似文献   
26.
The purpose of this open study was to evaluate the rate and extent of the penetration of sertaconazole nitrate (CAS 99592-32-2, Zala?n) penetration into the stratum corneum/lucidum of the human skin. Selected areas of 9 cm2 each of the back skin of 12 healthy volunteers were exposed over 8 different time intervals (between 0 and 48 h) to 100 mg of a 2% cream preparation of the compound or to placebo. Using a HPLC-assay the relative amounts of the applied dose of sertaconazole nitrate were determined in the residual cream of the skin surface as well as in 3 layers of the epidermis obtained by the stripping technique. Sertaconazole nitrate was shown to penetrate into the stratum corneum shortly after application, disappearing from the application areas with a mean apparent half-life of approximately 60 h. Immediately after topical application the residual amount of the applied mean dose of 2103 +/- 146.3 microg on the skin's surface was 88.9 +/- 2.3%, decreasing steadily to 52.4 +/- 8.5% after 48 h. A relevant amount of the applied dose (5.3 +/- 3.0%) was recovered from the stratum corneum already 30 min after application, and 3 h after administration a plateau was reached (6.9 +/- 3.2) which could be maintained until 48 h. A gradient from the site of application to the epidermis was apparent since the amounts recovered in The estimated average level of sertaconazole nitrate for a volume of 1 mL of stratum corneum after application of 100 mg cream was 1409 microg immediately after application and reached a plateau at 3 h with 9029 microg. Although not directly measured, the results also gave information about the mean amount of sertaconazole nitrate that penetrated through the stratum corneum and deeper layers allowing an estimate of the total mean amount of compound penetrating into the skin. The relative portion of this amount steadily increased from 1.1% of the applied dose at 0 h to 24.1% at 12 h, 34.2% at 24 h and finally to 37.6% of dose after 48 h of exposure. In view of the high target organ levels of the compound maintained over days, its rapid appearance in the stratum corneum after application and the earlier finding that Sertaconazole nitrate is not distributed into blood in substantial quantities the pharmacokinetic properties of this antifungal preparation therapy can be regarded as favourable.  相似文献   
27.
Ionizing radiation has long been known to induce heritable mutagenic change in DNA sequence. However, the genome-wide effect of radiation is not well understood. Here we report the molecular properties and frequency of mutations in phenotypically selected mutant lines isolated following exposure of the genetic model flowering plant Arabidopsis thaliana to fast neutrons (FNs). Previous studies suggested that FNs predominantly induce deletions longer than a kilobase in A. thaliana. However, we found a higher frequency of single base substitution than deletion mutations. While the overall frequency and molecular spectrum of fast-neutron (FN)-induced single base substitutions differed substantially from those of "background" mutations arising spontaneously in laboratory-grown plants, G:C>A:T transitions were favored in both. We found that FN-induced G:C>A:T transitions were concentrated at pyrimidine dinucleotide sites, suggesting that FNs promote the formation of mutational covalent linkages between adjacent pyrimidine residues. In addition, we found that FNs induced more single base than large deletions, and that these single base deletions were possibly caused by replication slippage. Our observations provide an initial picture of the genome-wide molecular profile of mutations induced in A. thaliana by FN irradiation and are particularly informative of the nature and extent of genome-wide mutation in lines selected on the basis of mutant phenotypes from FN-mutagenized A. thaliana populations.  相似文献   
28.
Studies on a platform technology able to deliver low-cost viral capsomeres and virus-like particles are described. The technology involves expression of the VP1 structural protein from murine polyomavirus (MuPyV) in Escherichia coli, followed by purification using scaleable units and optional cell-free VLP assembly. Two insertion sites on the surface of MuPyV VP1 are exploited for the presentation of the M2e antigen from influenza and the J8 peptide from Group A Streptococcus (GAS). Results from testing on mice following subcutaneous administration demonstrate that VLPs are self adjuvating, that adding adjuvant to VLPs provides no significant benefit in terms of antibody titre, and that adjuvanted capsomeres induce an antibody titre comparable to VLPs but superior to unadjuvanted capsomere formulations. Antibodies raised against GAS J8 peptide following immunization with chimeric J8-VP1 VLPs are bactericidal against a GAS reference strain. E. coli is easily and widely cultivated, and well understood, and delivers unparalleled volumetric productivity in industrial bioreactors. Indeed, recent results demonstrate that MuPyV VP1 can be produced in bioreactors at multi-gram-per-litre levels. The platform technology described here therefore has the potential to deliver safe and efficacious vaccine, quickly and cost effectively, at distributed manufacturing sites including those in less developed countries. Additionally, the unique advantages of VLPs including their stability on freeze drying, and the potential for intradermal and intranasal administration, suggest this technology may be suited to numerous diseases where adequate response requires large-scale and low-cost vaccine manufacture, in a way that is rapidly adaptable to temporal or geographical variation in pathogen molecular composition.  相似文献   
29.
Exogenous estradiol (E) is used occasionally to treat the side effects associated with androgen-deprivation in men, but its effects on sleep patterns have received little attention. We examined whether E modulates sleep patterns and recovery from sleep loss in castrated male rats. Adult male rats were castrated and implanted subcutaneously with Silastic tubes containing either oil (Cast + Oil) or E (Cast + E). Sham-operated male rats (Intact) were implanted with oil-filled tubes. All rats were also implanted with EEG and EMG electrodes for sleep/wake recordings. After two weeks, polysomnographic recordings were made before, during, and following 6 h of sleep deprivation (SD). At baseline, the Cast + Oil group showed sleep and EEG patterns similar to those in the Intact group. Compared to these groups, the Cast + E group spent more time awake during the dark (active) phase, and showed higher EEG theta power (a measure of cortical activation) during wake and rapid eye movement (REM) sleep in both the light and dark phases. Following SD, the Cast + E group showed a larger increase from baseline in REM sleep amount, compared to the Cast + Oil group. The Cast + Oil group showed prolonged rebound in non-REM sleep and EEG delta power, and reduced REM sleep rebound, compared to the other two groups. These results indicate that E treatment in castrated male rats promotes baseline wakefulness during the active phase, and facilitates recovery of REM sleep after acute sleep loss. The possible benefit of E treatment for improving sleep quality in androgen-deprived men remains to be investigated.  相似文献   
30.
Five Babesia bovis recombinant proteins, including merozoite surface antigen 2c (BbMSA-2c), C-terminal rhoptry-associated protein 1 (BbRAP-1/CT), truncated thrombospondin-related anonymous protein (BbTRAP-T), spherical body protein 1 (BbSBP-1), and spherical body protein 4 (BbSBP-4), were evaluated as diagnostic antigens to detect the infection in cattle. The recombinant proteins were highly antigenic when tested with experimentally B. bovis-infected bovine serum in Western blot analysis. Furthermore, five antisera that had been raised against each of the recombinant proteins reacted specifically with the corresponding authentic protein, as determined in Western blot analysis. Next, enzyme-linked immunosorbent assays (ELISAs) using these recombinant proteins were evaluated for diagnostic use, and the sensitivity and specificity of each protein were demonstrated with a series of serum samples from experimentally B. bovis-infected cattle. Furthermore, a total of 669 field serum samples collected from cattle in regions of B. bovis endemicity in seven countries were tested with the ELISAs, and the results were compared to those of an indirect fluorescent antibody test (IFAT), as a reference. Among five recombinant antigens, recombinant BbSBP-4 (rBbSBP-4) had the highest concordance rate (85.3%) and kappa value (0.705), indicating its reliability in the detection of specific antibodies to B. bovis in cattle, even in different geographical regions. Overall, we have successfully developed an ELISA based on rBbSBP-4 as a new serological antigen for a practical and sensitive test which will be applicable for epidemiologic survey and control programs in the future.  相似文献   
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