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31.
Mucormycosis is a rare fungal infection of childhood, occurring mainly in
patients with chronic illnesses such as diabetes and malignancies. The
fungus seldom grows in culture and confirmation of the diagnosis depends on
histologic examination of infected tissues. To date, the reported natural
history of the disease has been rapid progression and a fatal outcome.
Therefore, the importance of early diagnosis by tissue biopsy and early
treatment with surgical debridement and systemic antifungal therapy cannot
be overemphasized. The pulmonary system is the most common site for
mucormycosis in patients with leukemia. We report what we believe to be the
first successfully treated case of isolated muscular mucormycosis occurring
in a child with biphenotypic acute leukemia. The diagnosis was made
promptly by tissue examination at the time of surgical debridement. The
patient was also given systemic amphotericin-B therapy.
相似文献
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The role of divalent cations in platelet adherence to deendothelialized human arteries in flowing blood was investigated in an annular perfusion chamber. Spreading of platelets on the subendothelium was impaired below 30 microM of free Ca2+ ions (Ca2+). When Ca2+ was replaced by Mg2+, adherence was unchanged in perfusates without exogenous factor VIII-von Willebrand factor (FVIII-vWF), but the ability of FVIII-vWF to support platelet adherence was lost. Binding of FVIII-vWF to the vessel wall was independent of divalent cations, but bound FVIII-vWF was only able to mediate adherence after exposure to Ca2+. Pretreatment of FVIII-vWF with the calcium chelator EGTA (10 mM) resulted in loss of the ability to facilitate platelet adherence, while the ristocetin cofactor activity remained intact. Full restoration of the ability to mediate platelet adherence could only be obtained by prolonged dialysis against Ca2+ in the millimolar range. These data indicate that divalent cations have at least two separate roles to play in supporting platelet adherence: (1) platelet spreading on the subendothelium requires Ca2+ or Mg2+; (2) FVIII-vWF should be exposed to Ca2+ to obtain its optimal biologic activity in supporting platelet adherence. 相似文献
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C V Pillay S Somers J Booyens M G Moshal J V Bryer 《Suid-Afrikaanse tydskrif vir geneeskunde》1977,51(25):915-919
The ultrastructure of the human parietal cell at rest, after stimulation of gastric acid secretion by pentagastrin and after inhibition with propantheline or cimetidine, an H2-receptor antagonist, was studied. On stimulation there was an increase in the total secretory surface area of the gastric gland and canaliculus, with a concomitant decrease in the tubulovesicular system. On inhibition there was a decrease in the secretory surface area and a corresponding increase in the tubulovesicular system. These results are in agreement with other reports and support the hypothesis that during secretion of acid the tubulovesicular system increases the secretory surface by eversion or fusion of the vesicles and tubules with the plasmalemma. On inhibition there is thought to be reformation of the tubulovesicular system by pinocytosis. There is also ultrastructural evidence for the theory of membrane flow between the tubulovesicular system and the microvilli of the canaliculus and gastric lumen. Furthermore, there was an increase in lysosomal activity after the administration of the inhibiting drugs. It is suggested that the increased lysosomal activity could be involved in reducing the quantity of membrane after the membrane flow which occurs on gastric acid inhibition. 相似文献
38.
Background
Despite its known advantages, breastfeeding rates are low world over. Large number of factors affect breastfeeding. This study was designed to detect maternal and neonatal factors that adversely affect breastfeeding in the perinatal period.Methods
A prospective, single-blinded study was conducted on randomly chosen mother-infant pairs in the maternity ward of a tertiary care service hospital. Only full term singletons born by normal vaginal delivery were studied. The B.R.E.A.S.T observation score and time spent by the infant at the mother''s breast were primary outcome variables. Maternal age, gravida, para status and education level were recorded. Birth weight, sex, gestation age of the infant and time interval from birth to observation were also recorded. Initial univariate analysis followed by multivariate analysis was performed using SPSS ver 7.5 software.Results
A total of 54 mother-infant pairs formed the study group; 19(35.2%) were primigravidas. Primigravidas status of the mother led to significantly lower scores (p<0.04; 95% CI 0.10 to 3.62) as did maternal age < 26 years (p<0.04; 95% CI 0.2. to 3.46) on univariate analysis. Low birth weight (<2500 g) was the only neonatal factor that significantly lowered breastfeeding scores (p<0.02;95%Cl 0.56 to 6.31). On multivariate analysis only primigravida status was significantly associated with lower scores (p<0.02). The alpha value of the study was 5% and the power was 74%. Time spent by infant on breast was not significantly different between primigravida and non-primigravida mothers.Conclusion
Primigravida status adversely affects breastfeeding scores; therefore counseling and support should be focused on this group. Extra care should also be taken to ensure adequate breastfeeding by younger mothers and in those with low birth weight infants. Larger studies with long-term follow up will be able to identify other factors and dertermine the effects of focused counseling and support in the perinatal period upon long-term breastfeeding rates.Key Words: Breastfeeding, Primigravida, Counseling 相似文献39.
Background
The present study was conducted to study the efficacy and toxicity profile of methotrexate chloroquine combination in treatment of active rheumatoid arthritis.Methods
24 patients of rheumatoid arthritis confirming to revised American Rheumatism Association (ARA) criteria were studied prospectively for twenty months. Clinical evaluation was made every 3 months. Clinical disease variables measured at each visit were number of joints with swelling, number of joints with tenderness and pain, duration of morning stiffness and physician and patient assessment of disease activity. Blood counts, liver function tests and other adverse effects due to drugs were monitored every 2 months.Results
10 patients demonstrated more than 50% improvement. 4 patients withdrew from study, 2 because of excessive nausea and vomiting and 2 because of noncompliance. Other side effects noted were hyperpigmentation, photosensitivity, skin rashes, raised transaminases and stomatitis.Conclusion
Methotrexate chloroquine combination has good efficacy and toxicity profile. Gastrointestinal side effects are most common and usually responsible for the discontinuation of the drugs.Key Words: Rheumatoid arthritis, Methotrexate, Chloroquine, Efficacy, Toxicity 相似文献40.
Dr. S. P. Pillay F.R.C.S. M. G. Moshal M.R.C.P. F.A.C.G. J. M. Spitaels M.D. R. Bhoola M.R.C.P. P. Reddy M.B. Ch.B. H. Engelbrecht D.M.R.D. F.F.R. L. W. Baker F.R.C.S. 《Diseases of the colon and rectum》1981,24(2):107-113
The etiology of colonic strictures in 263 South African black and Indian patients is presented. Nonmalignant lesions accounted
for strictures in two-thirds of the patients and included amebiasis (27), tuberculosis (24), nonspecific colitis (30), ulcerative
colitis/Crohn's colitis (11) and other lesions (36). Malignant lesions caused strictures in approximately a third of the black
and Indian patients, which is higher than in other reported series in blacks. Accurate clinical diagnosis is difficult and
early histologic confirmation is mandatory in order to institute rational management. Strictures of the right colon in the
black population are more likely to be benign, except in younger patients. Leftsided colonic strictures have an equal chance
of being benign or malignant, and early histologic confirmation is essential. The coexistence of an underlying malignant lesion
in association with an inflammatory lesion in an endemic area should always be considered, particularly if it fails to respond
to empirical therapy within a short period of time. 相似文献