首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   443篇
  免费   31篇
耳鼻咽喉   7篇
儿科学   55篇
妇产科学   13篇
基础医学   55篇
口腔科学   11篇
临床医学   52篇
内科学   97篇
皮肤病学   4篇
神经病学   21篇
特种医学   60篇
外科学   27篇
综合类   10篇
预防医学   30篇
眼科学   3篇
药学   15篇
中国医学   1篇
肿瘤学   13篇
  2017年   4篇
  2016年   3篇
  2015年   16篇
  2014年   20篇
  2013年   15篇
  2012年   12篇
  2011年   12篇
  2010年   15篇
  2009年   5篇
  2008年   6篇
  2007年   5篇
  2006年   9篇
  2005年   13篇
  2004年   3篇
  2003年   7篇
  2002年   7篇
  2001年   7篇
  2000年   7篇
  1999年   9篇
  1998年   6篇
  1997年   14篇
  1996年   12篇
  1995年   12篇
  1994年   16篇
  1993年   9篇
  1992年   12篇
  1991年   9篇
  1990年   9篇
  1989年   20篇
  1988年   18篇
  1987年   15篇
  1986年   12篇
  1985年   12篇
  1984年   14篇
  1983年   8篇
  1982年   7篇
  1981年   9篇
  1980年   8篇
  1979年   3篇
  1978年   8篇
  1977年   10篇
  1976年   7篇
  1975年   6篇
  1973年   10篇
  1972年   7篇
  1969年   4篇
  1968年   5篇
  1967年   3篇
  1965年   2篇
  1902年   2篇
排序方式: 共有474条查询结果,搜索用时 15 毫秒
1.
Haemophilus influenzae vaccine containing polyribosyl ribitol phosphate (PRP) or PRP covalently linked to diphtheria toxoid (PRP-D) was given to 94 healthy infants 17 to 22 months of age at the same time, but not at the same site, as a diphtheria-tetanus-pertussis booster. Systemic reactions were similar in the two vaccine groups and resembled those expected with the diphtheria-tetanus-pertussis injection alone. Six (13%) and seven (14%) of the PRP and PRP-D recipients, respectively, had minor local reactions to the Haemophilus vaccine. Among the 77 children who were not already naturally immune (ie, anti-PRP antibody concentration of less than or equal to 0.15 micrograms of protein per milliliter) before vaccination, PRP-D was significantly more effective than PRP in inducing protective levels of antibody. Only 15 (43%) of the 35 nonimmune PRP recipients achieved a concentration of greater than or equal to 0.15 microgram/mL and only seven (20%) reached a concentration greater than or equal to 1.0 micrograms/mL following vaccination. In contrast, 34 (81%) of the 42 nonimmune recipients of PRP-D had a concentration of greater than or equal to 0.15 microgram/mL following vaccine and 32 (62%) had a concentration of greater than or equal to 1.0 micrograms/mL (P less than or equal to .001). These results suggest that more than one-half of nonimmune 18-month-old infants will not respond to PRP with protective levels of antibody. In light of the current data, recommendation for revaccination at 24 months of age for those immunized at any younger age is appropriate.  相似文献   
2.
3.
Different doses of hepatitis B virus vaccine—prepared by Korea Green Cross Corporation, were given to healthy infants born to HBsAg-negative mothers at birth, 1 and 6 months of age. A dose of 2 μg was administered intradermally in Group A and, in the three other groups, the vaccine was given intramuscularly (i.m.). An adequate follow-up observation was possible for 9 months after birth in 22, 25, 23 and 21 infants in Groups A, B, C and D, respecvely.
Group C (5 μg, i.m.) produced seroconversion most rapidly, showing the highest rate (96%) at 9 months of age. The lowest seroconversion rate (5%) was found at the age of 1 month in Group A subjects, but the rate increased to 91% after a booster dose was given at 6 months of age.
While it can be concluded that a 5 μg i.m. dose of vaccine at 0, 1 and 6 months of age is optimum for the immunization of infants in efficacy and economy, a 2 μg intradermal dose can also be considered as an immunogenic and economical regimen, though the immune response is slower and a special technique is required for immunization.  相似文献   
4.
A documentation system that facilitates accurate and complete recording is needed by every obstetric/neonatal nursing service. Developing an individualized system is a major undertaking. However, specific steps can be taken to ease the process. These steps are described, beginning with the assessment phase and concluding with evaluation.  相似文献   
5.
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
6.
The spontaneously hypertensive rat (SHR) is behaviorally hyperactive relative to the Wistar-Kyoto rat (WKY). By breeding SHR with WKY, followed by inbreeding, two new strains have been developed in which hypertension seems to be separated from hyperactivity to novel stimuli: the WKHT and the WKHA strains. The main purpose of the present study was to determine which behavioral characteristics of SHR have been dissociated from the hypertensive trait in the WKHA strain. Male SHR, WKY, WKHT, and WKHA were subjected to three protocols: 1) Two forced-exploration tests, where the results showed that both the SHR and the WKHA rats were hyperactive. 2) A free-exploration open field, where the SHR was more active than the other strains, showing shorter latencies to leave the home cage, spending more time in the field, ambulating and rearing more. Furthermore, the WKHT behavior was more similar to the SHR behavior than the WKHA behavior. 3) A two-component schedule of reinforcement, where one component (fixed-interval 2 min) was signaled by houselight on and the other (extinction, EXT) by houselight off. In this test, the SHR behavior was markedly different from that of the three other strains: the fixed-interval scallop, the accelerated responding towards the end of the interval, was steeper in SHR than in the other groups. The SHR emitted more responses during the extinction component of the schedule. The SHR hyperactivity was dependent upon the reinforcement value of the water deliveries and was increased even further by sensory-reinforcing respones feedback lights. Thus, the hyperactivity of the WKHA strain seems to be less pervasive than that of the SHR.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
8.
To distinguish sinusitis from uncomplicated "colds," we examined lactoferrin and eosinophilic cationic protein (ECP) in nasal secretions. Lactoferrin titers were >/=1:400 in 4% of persons with uncomplicated colds and controls but in 79% of persons with sinusitis or purulent sputa. ECP levels were >200 ng/ml in 61% of persons with colds and >3,000 ng/ml in 62% of persons with sinusitis. Nasal lactoferrin helps distinguish sinusitis from colds.  相似文献   
9.
Four inbred rat strains, all derived from Wistar-Kyoto (WKY) rats, express hypertension and hyperactivity in all combinations: SHRs have both traits, WKYs have neither, WKHAs are hyperactive/normotensive, and WKHTs are hypertensive/normoactive. Rats of the four strains were tested for aggression, at one time only, by pairing subjects of same sex, same age, but different strain, in a novel arena, i.e., on neutral ground, for three consecutive, 5-min observation periods. Total aggression scores were highest in females, highest in the first 5-min period, and lower at 7-9 months than at younger ages. Allogrooming was more frequently observed than other types of aggression, such as attacks, mounts, aggressive postures, and blocks. Allogrooming scores were significantly elevated in the hypertensive strains, especially WKHT, and very low in the hyperactive strains, especially WKHA. The other forms of aggression were significantly higher in females with hyperactivity. It was concluded that interstrain aggression, as seen in SHRs and WKYs, is differentially expressed by two new strains genetically derived from them. Furthermore, no one strain among these four expresses all components of the behavioral responses seen in this form of aggression.  相似文献   
10.
BACKGROUND: The concentration of rhinovirus in nasal wash specimens from infected volunteers peaks at 48-72 h after inoculation. The volume of expelled nasal fluid peaks at the same time, raising the question of whether the viral concentration in nasal wash reflects viral replication in nasal cells or merely the production of an increased volume of nasal fluid during a cold. OBJECTIVES: To determine the amount of rhinovirus in nasal lining fluid during colds before the nasal fluid has been diluted in a nasal wash. STUDY DESIGN: Rhinovirus titers were determined in nasal wash specimens collected daily for five days from 14 subjects with type16 rhinovirus infection. The urea concentration in nasal lining fluid equals that in blood. By determining the urea concentration in a nasal wash and comparing it to the urea concentration in blood from the same subject, it was possible to determine the amount of dilution of the nasal lining fluid. The dilution factor (reciprocal of the dilution) was then used to calculate the viral concentration in undiluted nasal lining fluid. RESULTS: The dilution factor in 70 nasal washes varied from 5 to 64. The viral GMTs (+S.E.) in nasal washes were 1.79 (+0.3) TCID(50)/ml at 24 h, 3.11 (+0.15) at 48 h, and 2.61 (+0.3) at 72 h. The viral GMTs in nasal lining fluid, based on urea adjusted values, paralleled those in nasal washes but were approximately one log higher. Virus concentrations returned to near baseline values by day 5. CONCLUSIONS: The temporal pattern of rhinovirus shedding observed in nasal wash specimens, with a peak in virus concentration at 48-72 h after infection, is a true indication of virus production in nasal cells and not an artifact of the increased amount of nasal fluid produced during the early phase of a cold.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号