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71.
Objective: To determine whether post-extubation respiratory support via nsNIPPV decreases the need for mechanical ventilation (MV) compared to nasal continuous positive airway pressure (NCPAP) in preterm infants with respiratory distress syndrome (RDS).

Methods: In this randomized, controlled, open, prospective, single-center clinical trial, we randomly assigned preterm ventilated infants with RDS to either nsNIPPV or NCPAP after extubation. The primary outcome, extubation failure, was defined by pre-specified failure criteria in the 72 hours after extubation.

Results: A total of 63 preterm ventilated infants were randomized to receive either nsNIPPV (n?=?31) or NCPAP (n?=?32). Extubation failure occurred in six (19.3%) of nsNIPPV group compared with nine (28.12%) of NCPAP group and was statistically not significant (p?=?0.55). The duration of NIV was significantly lower in nsNIPPV group as compared to NCPAP group (40.4?±?39.3 hours versus 111.8?±?116.4 hours, p?=?0.003). The duration of supplementary oxygen was significantly lower in nsNIPPV versus NCPAP group (84.9?±?92.1 hours versus 190.1?±?140.5 hours, p?=?0.002). The rates of BPD in nsNIPPV group (2/29, 6.9%) were significantly lower than in NCPAP group (9/28, 32.14%) (p?=?0.02).

Conclusions: Compared to NCPAP, nsNIPPV appears to be a feasible mode of extubation in preterm infants with significant beneficial effects of reduced duration of NIV support, supplementary oxygen and decreased rates of BPD.  相似文献   
72.
The distribution of a previously described repeated DNA sequence present as a 1.3-kb PstI fragment in the genome of the rice blast fungus Magnaporthe grisea was analysed by carrying out DNA fingerprint analysis of 36 isolates including rice, non-rice and laboratory strains. The analysis of various higher-molecular-weight PstI fragments with homology to the 1.3-kb repeat revealed that these may arise predominantly from transposon insertions or point mutations. Analysis of a 5.1-kb derivative revealed both a point mutation at a PstI site and an insertion of a putative transposable element which caused an increase in molecular weight from 1.3 to 5.1 kb. Another repeat element of 1.4 kb was identified and found to exist in association with the 1.3-kb repeat. Both 1.3- and 1.4-kb elements were found to be parts of MGR583 (Hamer et al. 1989), a LINE-like element. These elements were present in a high copy number in all the rice and a majority of non-rice pathogens indicating that MGR583 is not a host-specific sequence as reported earlier. Our results suggest that repeated DNA elements in M. grisea have amplified independently of one another and further indicate that different isolates of M. grisea may have evolved from several distinct lines of origin. Received: 12 April / 12 November 1996  相似文献   
73.
Egg-sharing in assisted conception: ethical and practical considerations   总被引:1,自引:5,他引:1  
The present acute shortage of eggs for donation cannot be overcomeunless adequate guidelines are set to alleviate the anxietiesregarding payments, in cash or kind, to donors. The currentHuman Fertilisation and Embryology Authority (HFEA) guidelinesdo not allow direct payment to donors but accept the provisionof lower cost or free in-vitro fertilization (IVF) treatmentto women in recognition of oocyte donation to anonymous recipients.Egg-sharing achieved in this way enables two infertile couplesto benefit from a single surgical procedure. However, the practicalguidelines related to this approach are ill-defined at the presenttime leading to some justifiable uncertainty. A pilot studywas therefore undertaken in order to establish the place ofegg-sharing in an assisted conception programme. The currentHFEA guidelines on medical screening of patients, counselling,age and rigid anonymity between the donor and recipient werefollowed. The study involved 55 women (25 donors and 30 recipients)in 73 treatment cycles involving fresh and frozen-thawed embryos.Donors were previous IVF patients who, regardless of their abilityto pay, shared their eggs equally with matched anonymous recipients.They paid only for their consultations and tests right up tothe point of being matched with a recipient The sole recipientpaid the cost applicable in egg donation of a single egg collection,although both received embryo transfers. The results indicatethat although the recipients were older than the donors (41.4± 0.9 versus 31.6 ± 0.5 years), and there wasno difference in the mean number of eggs allocated, the percentagefertilization rates, or the mean number of embryos transferred,there were more births per patient amongst recipients than amongstdonors (30 versus 20%). We conclude that providing the donorsare selected carefully, this scheme whereby a sub-fertile donorhelps a sub-fertile recipient is a very constructive way ofsolving the problem of the shortage of eggs for donation. Thereare also the advantages of including a group of women who wouldotherwise be denied treatment Problems related to ‘patientcoercion’ can, in our view, be fully overcome by the applicationof strict common-sense safeguards. The ideal of pure altruismis not without its medical and moral risk. The success of egg-sharingdepends on shared interests and a degree of altruism betweenthe donor, the recipient and the centre. The current HFEA guidelinesshould be applauded for enabling a highly effective conceptof mutual help to develop.  相似文献   
74.
We describe the clinical and demographic characteristics, virological follow-up, and management of five confirmed monkeypox cases from New Delhi, India without any international travel history. The viral load kinetics and viral clearance were estimated in oropharyngeal swabs (OPS), nasopharyngeal swabs (NPS), EDTA blood, serum, urine, and various lesion specimens on every fourth day of follow-up ranging from 5 to 24 post onset day (POD) of illness. All five cases presented with mild to moderate-grade intermittent fever, myalgia, and lesions on the genitals, groins, lower limb, trunk, and upper limb. Four cases had non-tender firm lymphadenopathy. No secondary complications or sexually transmitted infections were recorded in these cases except for the presence of viral hepatitis B infection marker hepatitis B virus surface antigen (HBsAg) in one case. All the cases were mild and had a good recovery. A higher viral load was detected in lesion fluid (POD 9), followed by lesion roof (POD 9), urine (POD 5), lesion base (POD 5), and OPS/NPS (POD 5). The monkeypox virus (MPXV) DNA was detected in clinical samples from 5th to 24th POD. These monkeypox cases without international travel history suggest the underdiagnosed monkeypox infection in the community. This emphasizes the need for active surveillance of MPXV in the high-risk population such as men having sex with men and female sex workers.  相似文献   
75.
Ahuja TK  Wu SH 《Neuroscience》2007,145(3):851-865
The inferior colliculus (IC) can be divided into three anatomical subdivisions: the central nucleus (ICc), the dorsal cortex (ICd) and the external cortex (ICx). ICx receives its primary auditory inputs from ICc and auditory cerebral cortical areas, and non-auditory inputs from regions of motor and other sensory systems. This wide array of projections makes the ICx a distinct structure within the auditory brainstem. The purpose of the current study was to comprehensively characterize the neuronal population of ICx, by intrinsic and synaptic response properties. Visual whole-cell patch clamp recordings were taken from ICx neurons (N=129) from rats between postnatal days 8 to 12. Neurons displayed various types of firing patterns in response to current injection, including regular, adapting, pauser and bursting. The regular cells constitute the majority (66%), followed by adapting (18%), pauser (13%) and bursting cells (2%). In response to hyperpolarizing current injection, many neurons illustrated a pronounced sag in the membrane potential, representing a hyperpolarization-activated current (I(h)). Some neurons (25%) displayed a Ca(2+)-dependent rebound depolarization following negative current injection. In response to depolarizing current injection, 70% of ICx neurons displayed a Ca(2+)-mediated potential expressed as Ca(2+) spikes/humps, uncovered when Na(+) and K(+) currents were removed. Also, spikes displayed an undershoot which was in part mediated by Ca(2+). Stimulation of the ICc elicited graded synaptic responses, which displayed a combination of excitatory and/or inhibitory potentials, with excitation being predominant across firing patterns. Neurons displayed temporal summation in response to repetitive stimulation at 20 Hz and higher. The results indicate a relatively modest diversity in firing pattern and in intrinsic membrane properties, making this subnucleus distinct from its counterparts within the IC. The data show that ICx receives major excitatory input from ICc, supporting its role in integrating signals from brainstem and directing information to higher brain centers.  相似文献   
76.
77.
BackgroundInjuries involving upper cervical spine are serious and fatal injuries which are associated with alteration of normal occipital–cervical anatomy. These injuries may result in permanent neurologic deficits or neck deformity if not treated in a timely and appropriate manner.ObjectiveTo evaluate the outcomes of neglected upper cervical spine injuries treated by various methods.Study designRetrospective study.Materials and methodsTwelve patients attending ER or OPD with a history of neck trauma and who were diagnosed with fractures and fracture dislocations C1 and C2 were included in the study. Fresh injuries sustained within a week were excluded from study. The outcomes were measured in terms of improvement in VAS, ODI Scores and correction of the neck deformity. Surgical parameters like duration of surgery and blood loss were also observed.ResultsEleven males and one female. The mean age was 40.9 ± 16.9 (07–67 years). Eleven patients underwent posterior instrumentation, while one patient was treated anteriorly. The mean delay in presentation was 28 ± 8.67 days (15–42 days). The mean duration of surgery was 188.3 ± 34.35 min (120–240 min), average blood loss was 350 ± 111.8 ml (150–600 ml). The mean VAS improved from 8.45 ± 0.89 to 3.9 ± 0.51 (p < 0.05). The mean ODI Pre-operatively was 88.45 ± 5.89 which improved to 31.9 ± 4.01 (p < 0.05). The neck deformity/torticollis was corrected in all the patients.ConclusionsNeglected upper cervical spine injuries are difficult to treat and a posterior approach is helpful in reducing the subluxations indirectly and to obtain a posterior fusion.  相似文献   
78.
In this paper, we present the first-ever experimental Compton line shapes of HgBr2 and HgI2 using 137Cs Compton spectrometer. To compare our experimental momentum densities, we have computed the Compton profiles using Hartree–Fock and density functional theory within linear combination of atomic orbitals. We have also computed the energy bands and density of states using the linear combination of atomic orbitals and full potential linearized augmented plane wave method. On the basis of equal-valence-electron-density profiles, it is seen that HgI2 is more covalent than HgBr2 which is in agreement with the valence charge densities. The experimental isotropic profiles are found to be relatively in better agreement with the Hartree–Fock data. We have also discussed the photoluminescence and detection properties of both the halides.  相似文献   
79.
Most traditional methods for T1 map estimation in MRI with fast low‐angle‐shot sequences are aimed at high efficiency by compromising the fitting accuracy. In this paper, the fundamental problem of parameter estimation in fast low‐angle‐shot MRI was re‐examined, and an accurate and fast optimization approach, named concatenated optimization for parameter estimation, was proposed for the regression of data points acquired with multiple flip angles. The initial estimation of T1 was obtained from the linear regression, followed by the constrained nonlinear regression based on the initial estimates. This heterogeneous initialization strategy improves the fitting accuracy and reduces the computational time. A computationally efficient implementation of concatenated optimization for parameter estimation was achieved based on the graphic processing unit, named as concatenated optimization for parameter estimation graphic processing unit. In experimental comparison with Fram's method and the Fitter Tool in Jim, the proposed methods are capable of achieving significantly higher efficiency and more accurate estimations. Magn Reson Med 63:1431–1436, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
80.
OBJECTIVES: There are very little data on elderly patients receiving electroconvulsive therapy (ECT) in India. This study was a preliminary attempt at characterizing the clinical and demographic profile of elderly subjects (>or=60 years) who received ECT in the psychiatric department of a teaching hospital in north India. METHODS: A retrospective case-note review was carried out to identify patients 60 years or older who had received ECT over an 8-year period at the Postgraduate Institute of Medical Education and Research, Chandigarh, India. Several details about their demographic and clinical profile, indications for ECT, response patterns, and adverse effects were extracted. RESULTS: Over the 8 years, 373 patients received ECT, of which 56 (15%) were 60 years or older. Complete records were available for only 50 of these patients. The majority (96%) had depression. The index depressive episode for which ECT was used was severe in 91.6% of the subjects, and 68% had not responded to adequate psychotropic treatment before ECT. Comorbid medical illnesses were present in 66% of cases and were associated with significantly higher risk of cognitive side effects. However, side effects were usually mild; there were no serious untoward events caused by ECT. About 80% to 90% showed some response to treatment. Those who had received inadequate antidepressant treatment before ECT were significantly more likely to respond to ECT. CONCLUSIONS: Elderly with depression constitute a substantial proportion of those receiving ECT in India. Use of ECT in this population seemed to be mainly restricted to those who were very severely ill and poorly responsive to medications. Electroconvulsive therapy seemed to be a safe and effective treatment in such situations. However, particular care may be required in the subgroup with comorbid physical problems that may be more vulnerable to cognitive adverse effects.  相似文献   
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