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31.
Some patients with autoimmune chronic active hepatitis as well as their disease-free first degree relatives show decreased suppressor cell activity of peripheral blood T lymphocytes. Studies were therefore undertaken in families ascertained by the presence of a single chronic active hepatitis patient to determine if this abnormality of immune regulation represents a genetic phenotype simply controlled by a gene or genes at a putative disease susceptibility locus and, further, if this locus showed linkage to either the HLA or the immunoglobulin constant region loci. In addition to determining circulating autoantibody status and genotyping for HLA and immunoglobulin allotypes, suppressor T cells were evaluated by surface markers and by determining their ability to suppress IgG secretion in vitro. The results suggest that immunoregulatory dysfunction in autoimmune chronic active hepatitis is a familial abnormality, but that this abnormality occurs independent of circulating autoantibody status and of the segregation of genes for HLA or immunoglobulin allotypes.  相似文献   
32.
Sexuality is an important contributing factor to quality of life and sense of well-being. All adults have the right to express their sexuality, regardless of their age. Research indicates, however, that older people frequently experience barriers to the expression of their sexuality. Many of these barriers are influenced by the health professionals and services that care for them. This paper will outline these barriers and identify strategies that the healthcare professional can implement to help improve practice in this area.  相似文献   
33.
A randomized, double-blind, crossover study was conducted in 10 patients to assess the effect of nifedipine versus placebo on total ischemic activity and circadian distribution of ischemic episodes. After baseline exercise treadmill testing and 48-hour ambulatory electrocardiographic ST-segment monitoring, patients received either nifedipine (mean dose, 80 mg/day) or placebo administered 4 times per day, with the initial dose taken immediately upon arising in the morning. Patients were maintained on a stable dose of each study drug for 7 days, after which they underwent repeat exercise treadmill testing and 48-hour ambulatory electrocardiography. During exercise treadmill testing, greater exercise duration was achieved by patients receiving nifedipine than by those receiving placebo (421 +/- 121 vs 353 +/- 155 seconds, respectively; p less than 0.05). Time to greater than or equal to 1 mm ST depression was significantly greater with nifedipine (282 +/- 146 seconds) than at baseline (130 +/- 72 seconds, p less than 0.003) and with placebo (150 +/- 98 seconds, p less than 0.0005). During ambulatory electrocardiographic monitoring, nifedipine reduced both the total number of ischemic episodes (18 vs 54 at baseline and 63 with placebo; p less than 0.02 for both) and the total duration of ischemia (260 vs 874 at baseline and 927 minutes with placebo; p less than 0.02 for both). The surge of ischemia between 06:00 and 12:00 noted at baseline and during placebo therapy was nearly abolished during nifedipine treatment. Nifedipine at this dosage, administered in this manner, is effective in reducing total ischemic activity and may prevent morning surges of ischemic episodes.  相似文献   
34.

Background

Growth faltering is a frequent public health problem in children and anthropometric measurements are useful tools for follow-up and early diagnosis. This problem has not been studied in the Cameroonian setting, that''s why we undertook this study.

Objectives

To have a synopsis of the nutritional status in apparently healthy children attending a vaccination clinic and show the importance of anthropometric measurements in routine child health care.

Design

A retrospective study.

Patients and Participants

1351 children aged (6–24months), who attended the vaccination clinic of the Yaounde Gynaeco-Obstetric and Pediatric Hospital over a 6 month period, were enrolled in the study.

Method

The registers of the vaccination clinic of the above hospital were retrospectively reviewed from 1st March to 31st August 2005. The following parameters were noted: age, height, weight, mid-upper arm circumference (MUAC), and Z scores calculated for the following indicators: weight for age (WAZ), weight for height (WHZ), and height for age (HAZ).

Results

Our results show that 12 children (1.1percent) in the 0–6 months age group and 4 (1.6 percent) in the 6–12 months age group had WAZ less than -2 indicating underweight. Also 10 children (0.9 percent) and 2 (0.8 percent) in the 0–6 and 6–12 months age groups respectively had WHZ less than −2, indicating wasting. HAZ was less than −2 in 70 children (6.4 percent) and in 8 (3.2 percent) in the 0–6 and 6–12 months age groups respectively indicating stunting. The MUAC was less than 12.5 cm in 6 children (2.4 percent).

Conclusions

From our results, we conclude that growth faltering is common in supposedly healthy children attending our vaccination clinic. Anthropometric measurements are thus recommended and should be encouraged in routine child care settings for early diagnosis of growth retardation and to provide useful interventions.  相似文献   
35.

Background and objective

Persistent pain is reported in up to 34% of patients following total knee arthroplasty (TKA) for management of knee osteoarthritis (KOA). Persistent pain in this group is thought to be at least partly reflective of pain sensory hypersensitivity. The objective of this study was to evaluate sensory hypersensitivity, using mechanical and thermal quantitative sensory testing, in patients about to undergo TKA.

Design and methods

Pressure pain thresholds (PPT) and cold pain thresholds (CPT) were recorded from 30 participants prior to their TKA, and compared with recordings taken from 30 healthy control participants of similar age and gender. Thresholds were recorded locally and remotely (other knee, deltoid) to the operative knee. Group comparisons (KOA, control, groups) were made using a general linear mixed models approach with age, gender, and body mass index (BMI) included as covariates. Pairwise comparisons were conducted with Bonferonni correction for multiple comparisons.

Results

Significantly lower PPTs were at all measured sites in the KOA group compared to the control group (P < 0.001 at all sites, except the deltoid P = 0.004). Males demonstrated higher pain threshold compared to females, averaged over all sites, P = 0.02. There were no observed between-group differences in CPT (P = 0.122).

Conclusions

This study suggested that some individuals about to undergo TKA for their advanced KOA demonstrated widespread mechanical sensory hypersensitivity. These findings have potentially important clinical implications regarding perioperative and longer-term pain management in these patients.  相似文献   
36.

Objective

To assess by stereology the placental structure in type 1 (T1DM) and type 2 (T2DM) diabetic pregnancies compared to normal non-diabetic (ND) controls.

Study design

Prospective case control study. Placentae were sampled in a systematic random fashion. Stereological analysis was performed using a computerised stereology programme (Image Pro 6.2, Media Cybernetics, Inc, Silver Spring MD, USA). Participants were matched for gender of infant and mode of delivery.

Main outcome measures

Volume, length and surface area of placental components; clinical outcome.

Results

Ten ND, eight T2DM and ten T1DM women consented to the study. There was no difference between the groups regarding maternal age, neonatal birth weight, or placental weight. On stereological examination, terminal villous volume was significantly increased in both diabetic groups compared to ND controls. Capillary volume and length was increased in T1DM pregnancies compared to ND and T2DM. Capillary length was increased in both diabetic groups compared to ND. When all diabetic groups were compared based on severity of glycaemia those with poor glycaemic control (HbA1c>7%) had higher placental capillary volume than those with good glycaemic control.

Conclusions

This study demonstrates an association between maternal diabetes and increased terminal villous volume. Additionally capillary volume and length is increased in the placentae of normally grown infants of T1DM diabetic mothers compared to non-diabetic controls. Maternal glycaemia appears to influence capillary, but not stromal, development. This suggests that factors other than glycaemia have a role in placental development in pre-gestational diabetes.  相似文献   
37.
We aimed to determine the incidence of Clostridium difficile infection (CDI), the molecular epidemiology of circulating C. difficile strains and risk factors for CDI among hospitalised children in the Auckland region. A cross-sectional study was undertaken of hospitalised children <15 years of age in two hospitals investigated for healthcare-associated diarrhoea between November 2011 and June 2012. Stool specimens were analysed for the presence of C. difficile using a two-step testing algorithm including polymerase chain reaction (PCR). C. difficile was cultured and PCR ribotyping performed. Demographic data, illness characteristics and risk factors were compared between children with and without CDI. Non-duplicate stool specimens were collected from 320 children with a median age of 1.2 years (range 3 days to 15 years). Forty-six patients (14 %) tested met the definition for CDI. The overall incidence of CDI was 2.0 per 10,000 bed days. The percentage of positive tests among neonates was only 2.6 %. PCR ribotyping showed a range of strains, with ribotype 014 being the most common. Significant risk factors for CDI were treatment with proton pump inhibitors [risk ratio (RR) 1.74, 95 % confidence interval (CI) 1.09–5.59; p?=?0.002], presence of underlying malignancy (RR 2.71, 95 % CI 1.65–4.62; p?=?0.001), receiving chemotherapy (RR 2.70, 95 % CI 1.41–4.83; p?=?0.003) and exposure to antibiotics (RR 1.17, 95 % CI 0.99–1.17; p?=?0.03). C. difficile is an important cause of healthcare-associated diarrhoea in this paediatric population. The notion that neonatal populations will always have high rates of colonisation with C. difficile may not be correct. Several risk factors associated with CDI among adults were also found to be significant.  相似文献   
38.
39.
Oocyte morphology predicts outcome of intracytoplasmic sperm injection   总被引:10,自引:14,他引:10  
To examine the influence of cytoplasmic morphology on the success rate of intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II oocytes was assessed after cumulus stripping. The main abnormalities detected were excessive granularity, cytoplasmic inclusions such as vacuoles, smooth endoplasmic reticulum clustering and refractile bodies. Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out of 161 with excessive granularity and 112 out of 138 with cytoplasmic inclusions. Very poor oocytes were not injected. No difference was found in fertilization rate. The embryos achieved cleaved normally and a similar number of good quality embryos among the three groups was noted. The outcome of transfer of embryos derived solely from normal oocytes (group A: 72 patients, 183 embryos) was compared with those from oocytes with cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A, 17 clinical pregnancies (24% per patient, implantation rate 10%) were established. In group B, only one clinical pregnancy (3% per patient, implantation rate 1%) was established, from the transfer of embryos derived from oocytes with homogeneous granularity of the cytoplasm. No pregnancy resulted following the transfer of embryos from eggs with cytoplasmic inclusions. The difference was statistically significant. The outcome of ICSI is dependent on the quality of the oocytes retrieved. Normal fertilization and early embryo development were achieved in oocytes with abnormal cytoplasm morphology, but the resulting embryos failed to demonstrate the same implantation potential as those derived from oocytes with normal cytoplasm.   相似文献   
40.
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